diff --git a/crates/benilla-app/assets/ui/ActionBar.xml b/crates/benilla-app/assets/ui/ActionBar.xml
index 24299ccd..767983d5 100644
--- a/crates/benilla-app/assets/ui/ActionBar.xml
+++ b/crates/benilla-app/assets/ui/ActionBar.xml
@@ -58,6 +58,28 @@
     <Script><![CDATA[
         BENILLA_FALLBACK_ICON = "Interface\\Icons\\INV_Misc_QuestionMark"
 
+        -- **The reference's action-bar constant block (ActionButton.lua:1-9).** Every one of these
+        -- was cited in comments across this file and MultiBars.xml and DEFINED nowhere, so an addon
+        -- reading them got nil. `zBar.lua:40` is the shape:
+        --
+        --     to = to or value.max or NUM_ACTIONBAR_BUTTONS
+        --     for i = from, to do          -- 'for' limit must be a number
+        --
+        -- Found by the use-probe, which is the only column that touches anything.
+        --
+        -- `CURRENT_ACTIONBAR_PAGE` is deliberately NOT among them. It is the reference's mutable
+        -- page cursor (ActionButton.lua:64/74 walk it), and benilla does not page the main bar that
+        -- way — the bonus offset re-pages it instead. Defining it as a frozen 1 would hand every
+        -- addon a number that is silently wrong forever; absent, a reader fails loudly and we find
+        -- out. That is this arc's own rule (1203/1205/1230: a silent wrong answer costs more than
+        -- a missing one), applied to ourselves.
+        NUM_ACTIONBAR_PAGES = 6
+        NUM_ACTIONBAR_BUTTONS = 12
+        BOTTOMLEFT_ACTIONBAR_PAGE = 6
+        BOTTOMRIGHT_ACTIONBAR_PAGE = 5
+        LEFT_ACTIONBAR_PAGE = 4
+        RIGHT_ACTIONBAR_PAGE = 3
+
         -- Ref ActionButton.lua:4 / UIParent.lua: the flash blink period and the range-check cadence.
         ATTACK_BUTTON_FLASH_TIME = 0.4
         TOOLTIP_UPDATE_TIME = 0.2
@@ -696,7 +718,7 @@
             end
             ExhaustionTick.timer = 1
             if not GameTooltip_AddNewbieTip then return end
-            GameTooltip_AddNewbieTip(bar, XPBAR_LABEL, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_XPBAR, 1)
+            BenillaTooltip_AddNewbieTipFor(bar, XPBAR_LABEL, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_XPBAR, 1)
             GameTooltip.canAddRestStateLine = 1
         end
 
@@ -916,13 +938,13 @@
         end
 
         -- ref l.389 (the held-open refresh) and l.400 (OnEnter), both the same call:
-        --     GameTooltip_AddNewbieTip(MAINMENUBAR_LATENCY_LABEL.." "..latency..MILLISECONDS_ABBR,
+        --     BenillaTooltip_AddNewbieTipFor(MAINMENUBAR_LATENCY_LABEL.." "..latency..MILLISECONDS_ABBR,
         --                              1.0, 1.0, 1.0, NEWBIE_TOOLTIP_LATENCY)
         -- So the reference hover is TWO lines — the number, then the wrapped explanation — seated
         -- at the default screen corner, not beside the meter (GameTooltip.xml, decision 0661).
         function BenillaPerformanceBar_ShowTooltip(owner)
             if not GameTooltip_AddNewbieTip then return end -- engine tests load file subsets
-            GameTooltip_AddNewbieTip(owner, BenillaPerformanceBar_TooltipText(), 1.0, 1.0, 1.0,
+            BenillaTooltip_AddNewbieTipFor(owner, BenillaPerformanceBar_TooltipText(), 1.0, 1.0, 1.0,
                 NEWBIE_TOOLTIP_LATENCY)
         end
 
diff --git a/crates/benilla-app/assets/ui/FriendsFrame.xml b/crates/benilla-app/assets/ui/FriendsFrame.xml
index 01ffe533..e4dbeef6 100644
--- a/crates/benilla-app/assets/ui/FriendsFrame.xml
+++ b/crates/benilla-app/assets/ui/FriendsFrame.xml
@@ -815,7 +815,7 @@
                                     StaticPopup_Show("ADD_FRIEND")
                                 end
                             </OnClick>
-                            <OnEnter>GameTooltip_AddNewbieTip(self, ADD_FRIEND, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_ADDFRIEND, 1)</OnEnter>
+                            <OnEnter>BenillaTooltip_AddNewbieTipFor(self, ADD_FRIEND, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_ADDFRIEND, 1)</OnEnter>
                             <OnLeave>GameTooltip:Hide()</OnLeave>
                         </Scripts>
                     </Button>
@@ -824,7 +824,7 @@
                         <Anchors><Anchor point="TOP" relativeTo="FriendsFrameAddFriendButton" relativePoint="BOTTOM"><Offset><AbsDimension x="0" y="-5"/></Offset></Anchor></Anchors>
                         <Scripts>
                             <OnClick>FriendsFrame_RemoveFriend()</OnClick>
-                            <OnEnter>GameTooltip_AddNewbieTip(self, REMOVE_FRIEND, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_REMOVEFRIEND, 1)</OnEnter>
+                            <OnEnter>BenillaTooltip_AddNewbieTipFor(self, REMOVE_FRIEND, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_REMOVEFRIEND, 1)</OnEnter>
                             <OnLeave>GameTooltip:Hide()</OnLeave>
                         </Scripts>
                     </Button>
@@ -833,7 +833,7 @@
                         <Anchors><Anchor point="LEFT" relativeTo="FriendsFrameAddFriendButton" relativePoint="RIGHT"><Offset><AbsDimension x="66" y="0"/></Offset></Anchor></Anchors>
                         <Scripts>
                             <OnClick>FriendsFrame_SendMessage()</OnClick>
-                            <OnEnter>GameTooltip_AddNewbieTip(self, SEND_MESSAGE, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_SENDMESSAGE, 1)</OnEnter>
+                            <OnEnter>BenillaTooltip_AddNewbieTipFor(self, SEND_MESSAGE, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_SENDMESSAGE, 1)</OnEnter>
                             <OnLeave>GameTooltip:Hide()</OnLeave>
                         </Scripts>
                     </Button>
@@ -842,7 +842,7 @@
                         <Anchors><Anchor point="TOP" relativeTo="FriendsFrameSendMessageButton" relativePoint="BOTTOM"><Offset><AbsDimension x="0" y="-5"/></Offset></Anchor></Anchors>
                         <Scripts>
                             <OnClick>FriendsFrame_GroupInvite()</OnClick>
-                            <OnEnter>GameTooltip_AddNewbieTip(self, GROUP_INVITE, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_GROUPINVITE, 1)</OnEnter>
+                            <OnEnter>BenillaTooltip_AddNewbieTipFor(self, GROUP_INVITE, 1.0, 1.0, 1.0, NEWBIE_TOOLTIP_GROUPINVITE, 1)</OnEnter>
                             <OnLeave>GameTooltip:Hide()</OnLeave>
                         </Scripts>
                     </Button>
diff --git a/crates/benilla-app/assets/ui/GameTooltip.xml b/crates/benilla-app/assets/ui/GameTooltip.xml
index 2b5fe2c5..70bf2e0f 100644
--- a/crates/benilla-app/assets/ui/GameTooltip.xml
+++ b/crates/benilla-app/assets/ui/GameTooltip.xml
@@ -102,7 +102,23 @@
         -- convention is to keep the ref NAME and take that frame as a leading parameter
         -- (GameTooltip_OnHide(self), GameTooltip_ClearMoney(frame) — same shift). Reference code
         -- pasted in verbatim must therefore have the owner threaded in as arg 1.
-        function GameTooltip_AddNewbieTip(owner, normalText, r, g, b, newbieText, noNormalText)
+        -- **The reference's exact signature, because a signature IS api (1199).** Ours used to take
+        -- the owner as arg 1; the reference takes none and reads `this`. Outfitter calls it the
+        -- reference's way (`OutfitterMinimapButton:OnEnter` -> `GameTooltip_AddNewbieTip(text, ...)`),
+        -- so its TEXT landed in our owner slot and `SetOwner` raised
+        -- "bad argument #2: error converting Lua string to table". Found by the use-probe, not by
+        -- reading: it only fires when something hovers.
+        --
+        -- Our own callers mostly hold the owner in a local that is NOT the firing frame (`bar`,
+        -- `button`, `frame`), so they use the explicit-owner variant below rather than `this`.
+        function GameTooltip_AddNewbieTip(normalText, r, g, b, newbieText, noNormalText)
+            BenillaTooltip_AddNewbieTipFor(this, normalText, r, g, b, newbieText, noNormalText)
+        end
+
+        -- The explicit-owner form our FrameXML uses. Same body the reference's has, with the owner
+        -- threaded rather than taken from `this` — kept under a Benilla name so it can never be
+        -- mistaken for a reference global an addon might call or replace.
+        function BenillaTooltip_AddNewbieTipFor(owner, normalText, r, g, b, newbieText, noNormalText)
             if SHOW_NEWBIE_TIPS == "1" then
                 GameTooltip_SetDefaultAnchor(GameTooltip, owner)
                 if normalText then
diff --git a/crates/benilla-app/assets/ui/MicroMenu.xml b/crates/benilla-app/assets/ui/MicroMenu.xml
index ae0f5bca..deb764f1 100644
--- a/crates/benilla-app/assets/ui/MicroMenu.xml
+++ b/crates/benilla-app/assets/ui/MicroMenu.xml
@@ -124,10 +124,10 @@
         end
 
         -- ref MainMenuBarMicroButton's OnEnter (l.13), verbatim bar the owner shift:
-        --     GameTooltip_AddNewbieTip(this.tooltipText, 1.0, 1.0, 1.0, this.newbieText)
+        --     BenillaTooltip_AddNewbieTipFor(this.tooltipText, 1.0, 1.0, 1.0, this.newbieText)
         function BenillaMicroButton_OnEnter(button)
             if not GameTooltip_AddNewbieTip then return end -- engine tests load file subsets
-            GameTooltip_AddNewbieTip(button, BenillaMicroButton_TooltipText(button), 1.0, 1.0, 1.0,
+            BenillaTooltip_AddNewbieTipFor(button, BenillaMicroButton_TooltipText(button), 1.0, 1.0, 1.0,
                 button.newbieText)
         end
 
diff --git a/crates/benilla-app/assets/ui/ScrollTemplates.xml b/crates/benilla-app/assets/ui/ScrollTemplates.xml
index 0cd2e865..a0d44cbe 100644
--- a/crates/benilla-app/assets/ui/ScrollTemplates.xml
+++ b/crates/benilla-app/assets/ui/ScrollTemplates.xml
@@ -104,6 +104,30 @@
         -- The added line is `SetValueStep(1)`: our bar's step is also its ARROW/WHEEL step
         -- (BenillaScrollBar_Step), so a bar that has not been through an _Update yet would step by
         -- nothing. The ref has no such coupling — its arrows move by half the bar's height.
+        -- The ScrollingEdit trio (ref UIPanelTemplates.lua l.307-317) — a multi-line EditBox
+        -- inside a ScrollFrame keeps the scroll child's rect in step as the text grows, and tracks
+        -- where the caret is so the OnUpdate can follow it.
+        --
+        -- Published under the REFERENCE's names because that is what an addon's XML wires: our
+        -- corpus hits it through `InviteOMaticOptionFormSpamPanelAIGSpamEditE...:OnTextChanged`,
+        -- which raised `attempt to call global 'ScrollingEdit_OnTextChanged'` the moment anyone
+        -- typed. Both take an OPTIONAL scroll frame and fall back to `this:GetParent()`, exactly as
+        -- the reference does — an addon that wires the bare name relies on that fallback.
+        --
+        -- `ScrollingEdit_OnUpdate`'s caret-follow scroll is NOT here: it needs the caret's own
+        -- offset from the font engine, which our EditBox does not report yet. Named rather than
+        -- stubbed silently — a stub that scrolls nowhere would look like a working caret-follow.
+        function ScrollingEdit_OnTextChanged(scrollFrame)
+            local f = scrollFrame or (this and this:GetParent())
+            if f and f.UpdateScrollChildRect then f:UpdateScrollChildRect() end
+        end
+
+        function ScrollingEdit_OnCursorChanged(x, y, w, h)
+            if not this then return end
+            this.cursorOffset = y
+            this.cursorHeight = h
+        end
+
         function ScrollFrame_OnLoad()
             getglobal(this:GetName() .. "ScrollBarScrollDownButton"):Disable()
             getglobal(this:GetName() .. "ScrollBarScrollUpButton"):Disable()
diff --git a/crates/benilla-app/assets/ui/TextStatusBar.xml b/crates/benilla-app/assets/ui/TextStatusBar.xml
index c89dea8f..e28fb8a8 100644
--- a/crates/benilla-app/assets/ui/TextStatusBar.xml
+++ b/crates/benilla-app/assets/ui/TextStatusBar.xml
@@ -147,7 +147,7 @@
                 TextStatusBar_UpdateTextString()
                 ShowTextStatusBarText(this)
                 if this.tooltipTitle and GameTooltip_AddNewbieTip then
-                    GameTooltip_AddNewbieTip(this, this.tooltipTitle, 1.0, 1.0, 1.0, this.tooltipText, 1)
+                    BenillaTooltip_AddNewbieTipFor(this, this.tooltipTitle, 1.0, 1.0, 1.0, this.tooltipText, 1)
                 end
             </OnEnter>
             <OnLeave>
diff --git a/crates/benilla-app/assets/ui/UnitFrames.xml b/crates/benilla-app/assets/ui/UnitFrames.xml
index a4cd8b04..b1f3dd41 100644
--- a/crates/benilla-app/assets/ui/UnitFrames.xml
+++ b/crates/benilla-app/assets/ui/UnitFrames.xml
@@ -339,12 +339,12 @@
             GameTooltip_SetDefaultAnchor(GameTooltip, frame)
             if SHOW_NEWBIE_TIPS == "1" then
                 if frame:GetName() == "PlayerFrame" then
-                    GameTooltip_AddNewbieTip(frame, PARTY_OPTIONS_LABEL, 1.0, 1.0, 1.0,
+                    BenillaTooltip_AddNewbieTipFor(frame, PARTY_OPTIONS_LABEL, 1.0, 1.0, 1.0,
                         NEWBIE_TOOLTIP_PARTYOPTIONS)
                     return
                 elseif UnitIsPlayer("target") and not UnitIsUnit("target", "player")
                     and not UnitIsUnit("target", "pet") then
-                    GameTooltip_AddNewbieTip(frame, PLAYER_OPTIONS_LABEL, 1.0, 1.0, 1.0,
+                    BenillaTooltip_AddNewbieTipFor(frame, PLAYER_OPTIONS_LABEL, 1.0, 1.0, 1.0,
                         NEWBIE_TOOLTIP_PLAYEROPTIONS)
                     return
                 end
diff --git a/crates/benilla-app/src/ui_script/action_bar_tests.rs b/crates/benilla-app/src/ui_script/action_bar_tests.rs
index 664924ce..2edaf353 100644
--- a/crates/benilla-app/src/ui_script/action_bar_tests.rs
+++ b/crates/benilla-app/src/ui_script/action_bar_tests.rs
@@ -1029,3 +1029,47 @@ fn the_bonus_action_bar_exists_hidden_and_takes_layout_calls() {
     );
     assert!(s.errors().is_empty(), "script errors: {:?}", s.errors());
 }
+
+/// **The reference's action-bar constants are real globals, not comments.**
+///
+/// `ActionButton.lua:1-9` defines them; this file and `MultiBars.xml` cited them in comments and
+/// defined none. An addon reading one got nil — `zBar.lua:40` is the shape,
+/// `to = to or value.max or NUM_ACTIONBAR_BUTTONS` feeding a numeric `for`, which raises
+/// `'for' limit must be a number`. Only the use-probe could find it: nothing else touches anything.
+///
+/// `CURRENT_ACTIONBAR_PAGE` is asserted ABSENT on purpose. It is the reference's mutable page
+/// cursor and benilla does not page the main bar that way; a frozen 1 would be silently wrong
+/// forever, where nil fails loudly. Pinned so a later "completeness" pass cannot quietly add it.
+#[test]
+fn the_reference_action_bar_constants_are_defined() {
+    let s = UiScript::new().unwrap();
+    load_action_bar(&s);
+
+    for (name, want) in [
+        ("NUM_ACTIONBAR_PAGES", 6),
+        ("NUM_ACTIONBAR_BUTTONS", 12),
+        ("BOTTOMLEFT_ACTIONBAR_PAGE", 6),
+        ("BOTTOMRIGHT_ACTIONBAR_PAGE", 5),
+        ("LEFT_ACTIONBAR_PAGE", 4),
+        ("RIGHT_ACTIONBAR_PAGE", 3),
+    ] {
+        assert_eq!(
+            s.eval::<i64>(&format!("return {name}")).unwrap(),
+            want,
+            "{name} must be the reference's value"
+        );
+    }
+
+    // zBar's exact expression, which raised before these existed.
+    assert_eq!(
+        s.eval::<i64>("local to = nil or nil or NUM_ACTIONBAR_BUTTONS local n = 0 for i = 1, to do n = n + 1 end return n")
+            .unwrap(),
+        12,
+        "zBar.lua:40's numeric for must have a limit"
+    );
+
+    assert!(
+        s.eval::<bool>("return CURRENT_ACTIONBAR_PAGE == nil").unwrap(),
+        "CURRENT_ACTIONBAR_PAGE is mutable page state we do not keep — nil fails loudly, a frozen 1 lies"
+    );
+}
diff --git a/crates/benilla-app/src/ui_script/faux_scroll_tests.rs b/crates/benilla-app/src/ui_script/faux_scroll_tests.rs
index f0b31f88..d6517bec 100644
--- a/crates/benilla-app/src/ui_script/faux_scroll_tests.rs
+++ b/crates/benilla-app/src/ui_script/faux_scroll_tests.rs
@@ -358,3 +358,50 @@ fn the_reference_on_vertical_scroll_path_runs_once_a_scroll_child_exists() {
         "and the addon's own update function ran"
     );
 }
+
+/// **The ScrollingEdit trio answers to the REFERENCE's names, and to a bare call.**
+///
+/// `InviteOMatic` wires `ScrollingEdit_OnTextChanged` straight into an EditBox's `OnTextChanged`
+/// and raised `attempt to call global` the moment anyone typed — found by the use-probe, since it
+/// only fires on input. Both helpers take an OPTIONAL scroll frame and fall back to
+/// `this:GetParent()` (ref `UIPanelTemplates.lua` l.307-310); an addon wiring the bare name depends
+/// on that fallback, so the no-argument path is what this test drives.
+#[test]
+fn scrolling_edit_helpers_answer_bare_calls_from_a_handler() {
+    let s = UiScript::new().unwrap();
+    load_xml(&s, "Fonts.xml");
+    load_xml(&s, "ScrollTemplates.xml");
+    load_inline(
+        &s,
+        r#"<Ui>
+            <ScrollFrame name="SeScroll">
+                <Size><AbsDimension x="200" y="100"/></Size>
+                <Anchors><Anchor point="CENTER"/></Anchors>
+                <ScrollChild>
+                    <EditBox name="SeEdit" multiLine="true">
+                        <Size><AbsDimension x="200" y="300"/></Size>
+                    </EditBox>
+                </ScrollChild>
+            </ScrollFrame>
+        </Ui>"#,
+    );
+
+    // Bare call with `this` set to the edit box — the addon's exact wiring.
+    s.run(
+        "this = SeEdit; ScrollingEdit_OnTextChanged(); ScrollingEdit_OnCursorChanged(0, 42, 0, 14); this = nil",
+    )
+    .unwrap();
+    assert!(
+        s.errors().is_empty(),
+        "bare calls must not raise: {:?}",
+        s.errors()
+    );
+
+    // OnCursorChanged records where the caret is, which is what an OnUpdate would follow.
+    assert_eq!(s.eval::<f32>("return SeEdit.cursorOffset").unwrap(), 42.0);
+    assert_eq!(s.eval::<f32>("return SeEdit.cursorHeight").unwrap(), 14.0);
+
+    // ...and the explicit-frame form works too (the reference's first branch).
+    s.run("ScrollingEdit_OnTextChanged(SeScroll)").unwrap();
+    assert!(s.errors().is_empty(), "explicit form: {:?}", s.errors());
+}
diff --git a/crates/benilla-ui/src/script/tooltip_spell.rs b/crates/benilla-ui/src/script/tooltip_spell.rs
index d571196e..ee3a931a 100644
--- a/crates/benilla-ui/src/script/tooltip_spell.rs
+++ b/crates/benilla-ui/src/script/tooltip_spell.rs
@@ -484,7 +484,25 @@ pub(super) fn install_methods(lua: &Lua, m: &Table) -> mlua::Result<()> {
     for (verb, helpful) in [("SetUnitBuff", true), ("SetUnitDebuff", false)] {
         m.set(
             verb,
-            lua.create_function(move |lua, (this, token, index): (Table, String, i64)| {
+            // `index` is `Value`, not `i64`, and that is a fidelity fix rather than laxity — the
+            // same correction `SetTexture` already carries. A C binding reads what it wants off
+            // the Lua stack: `lua_tonumber` on nil yields 0, which finds no aura and shows
+            // nothing. Typing it `i64` made us RAISE on a call the real client accepts silently.
+            //
+            // Found by the use-probe: `CT_AssistFrameDebuff1:OnEnter` calls
+            // `SetUnitDebuff(unit, this:GetID())` and the id is nil on a frame CT_UnitFrames
+            // created without one. It only fires on hover, so nothing before the probe saw it.
+            lua.create_function(move |lua, (this, token, index): (Table, String, Value)| {
+                let index = match &index {
+                    Value::Integer(i) => *i,
+                    Value::Number(n) => *n as i64,
+                    Value::String(s) => s
+                        .to_str()
+                        .ok()
+                        .and_then(|t| t.parse::<i64>().ok())
+                        .unwrap_or(0),
+                    _ => 0,
+                };
                 let hit = {
                     let model = lua.app_data_mut::<Model>().expect("model app_data");
                     let idx = usize::try_from(index.max(1) - 1).unwrap_or(0);
diff --git a/third_party/lua-src/BENILLA.md b/third_party/lua-src/BENILLA.md
new file mode 100644
index 00000000..bd6596d4
--- /dev/null
+++ b/third_party/lua-src/BENILLA.md
@@ -0,0 +1,69 @@
+# benilla's `lua-src` fork — what differs from upstream, and how to check
+
+Upstream: [`mlua-rs/lua-src-rs`](https://github.com/mlua-rs/lua-src-rs), MIT, version `550.0.0` —
+the version mlua 0.11 resolves to. Wired in through `[patch.crates-io]` in the workspace root.
+
+## Why a fork exists at all
+
+The 1.12 addon corpus is Lua **5.0** code. It uses the iterator-less generic-for:
+
+```lua
+for k, v in someTable do ... end        -- no pairs(), no iterator function
+```
+
+**183 of 218 corpus addons are reached by it** (118 carry it, 65 inherit it through a declared
+dependency), across 1,163 sites. On stock Lua 5.1 it raises `attempt to call a table value`, and it
+is the **first session-start error for 60 of 218 addons — three quarters of everything that breaks
+once the client is actually running**, eleven times the next cause.
+
+Lua 5.1 removed it at the **opcode** level, which is why no layer above the VM can reach it. Every
+other dialect gap this project has closed was reachable from inside Lua — `table.setn` is a library
+function, `bit` is a library, `print` is a global (decisions 1194, 1196). This one is not:
+
+- a `__call` metamethod would work, but the tables are the addon's own and Lua 5.1 has no
+  per-*type* default metatable for tables;
+- rewriting the chunk source means parsing Lua with a regex to tell `in t do` from `in pairs(t) do`,
+  and getting that wrong changes behaviour silently;
+- there is no `lua50` backend — `lua-src` ships 5.1 through 5.5 and every one of them removed it.
+
+## What is NOT being done
+
+**benilla is not adopting Lua 5.0.** We stay on 5.1.5 and restore the behaviour of a single opcode
+that Lua itself shipped and labelled `/* for compatibility only */`. Every other 5.1 fix, and the
+whole of mlua's surface, stay exactly as upstream. That is a far smaller commitment than a version
+downgrade, and it is the entire reason this is a one-hunk fork rather than a vendored 5.0.
+
+## The delta, and the command that proves it
+
+**Current state: no source hunk yet.** The `lua-5.1.5/` tree here is byte-identical to upstream's,
+and `src/lib.rs` differs only by having Lua 5.2/5.3/5.4/5.5 stripped from the `Version` enum (with
+their source trees deleted) — benilla builds 5.1 and only 5.1, and a fork that still *offered* the
+other four would answer a request for one with a missing directory at build time instead of a
+compile error.
+
+This ordering is deliberate: the build pipeline is proven transparent **before** any behavioural
+payload goes into it, so that when the suite moves, the patch is the only thing that could have
+moved it. Landed inert, with all tests passing, exactly so that claim is checkable.
+
+To verify the Lua sources against upstream at any time:
+
+```sh
+# 550.0.0 is the pinned version; adjust the path if cargo's registry hash differs.
+diff -r third_party/lua-src/lua-5.1.5 \
+  ~/.cargo/registry/src/*/lua-src-550.0.0/lua-5.1.5
+```
+
+Today that prints nothing. When the payload lands it must print **exactly** the hunk described in
+decision 1215 and nothing else — if it ever prints more, something crept in.
+
+## Status of the payload
+
+Blocked, deliberately, on a reverse-engineering answer from the sibling repo `wow-5875-re`: what the
+**real 1.12.1 client's own Lua** does when a generic-for's generator is a table. Stock Lua 5.0 is
+corroboration, not the authority — the client links 5.0 but may be modified.
+
+Checking stock 5.0 already corrected two assumptions the project had written down (it substitutes in
+`OP_TFORPREP`, an opcode 5.1 deleted, *not* in `OP_TFORLOOP`; and the test is a bare `ttistable`
+with **no** `__call` check, using the **global** `next` — so an addon that overwrites `next` changes
+loop behaviour). Two corrections from checking one step out is the reason for checking the next one
+before writing C.
diff --git a/third_party/lua-src/Cargo.toml b/third_party/lua-src/Cargo.toml
new file mode 100644
index 00000000..37eef0d0
--- /dev/null
+++ b/third_party/lua-src/Cargo.toml
@@ -0,0 +1,39 @@
+# A fork of the `lua-src` crate (MIT, github.com/mlua-rs/lua-src-rs), pinned to the version mlua
+# 0.11 asks for, carrying ONE deliberate change to the Lua 5.1.5 sources it compiles.
+#
+# WHY THIS EXISTS — decision 1215. The 1.12 addon corpus is written for Lua 5.0 and uses the
+# iterator-less generic-for (`for k, v in someTable do`) in 183 of 218 addons. Lua 5.1 deleted the
+# opcode that made it work, so on stock 5.1 it raises `attempt to call a table value` — the first
+# error for 60 of 218 addons at session start, three quarters of everything that breaks in a running
+# session. It is not reachable from inside Lua: not a library function, not a global, an OPCODE.
+#
+# WHAT IS AND IS NOT CHANGED. **Right now: nothing.** The `lua-5.1.5/` tree here is byte-identical
+# to upstream's, and this fork was landed inert on purpose — the pipeline is proven transparent
+# BEFORE any behavioural payload goes into it, so that when the suite moves, the patch is the only
+# thing that could have moved it. `BENILLA.md` carries the current state and the one command that
+# verifies the sources against upstream.
+#
+# When the payload does land we are still NOT adopting Lua 5.0: we stay on 5.1.5 and restore the
+# behaviour of one opcode Lua itself shipped and labelled "for compatibility only", so every other
+# 5.1 fix and mlua's whole surface stay intact.
+#
+# The crate's own `src/lib.rs` is upstream's, with Lua 5.2/5.3/5.4/5.5 stripped from the `Version`
+# enum and the trees deleted. That is deliberate rather than tidiness: benilla builds 5.1 and only
+# 5.1, and a fork that still *offers* the other four would answer a request for them with a missing
+# directory at build time instead of a compile error here.
+[package]
+name = "lua-src"
+version = "550.0.0"
+authors = ["Aleksandr Orlenko <zxteam@protonmail.com>"]
+edition = "2024"
+repository = "https://github.com/mlua-rs/lua-src-rs"
+license = "MIT"
+description = """
+Sources of Lua 5.1 and logic to build them — benilla's fork, see the header and BENILLA.md.
+"""
+
+[features]
+ucid = [] # accept UniCode IDentifiers (upstream's; inert here, it only ever gated 5.4/5.5)
+
+[dependencies]
+cc = "1.2"
diff --git a/third_party/lua-src/LICENSE b/third_party/lua-src/LICENSE
new file mode 100644
index 00000000..51637853
--- /dev/null
+++ b/third_party/lua-src/LICENSE
@@ -0,0 +1,43 @@
+MIT License
+
+Copyright (c) 2020 Aleksandr Orlenko
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+### Lua license ###
+
+Copyright © 1994–2017 Lua.org, PUC-Rio.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/third_party/lua-src/lua-5.1.5/lapi.c b/third_party/lua-src/lua-5.1.5/lapi.c
new file mode 100644
index 00000000..5d5145d2
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lapi.c
@@ -0,0 +1,1087 @@
+/*
+** $Id: lapi.c,v 2.55.1.5 2008/07/04 18:41:18 roberto Exp $
+** Lua API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <assert.h>
+#include <math.h>
+#include <stdarg.h>
+#include <string.h>
+
+#define lapi_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+
+
+
+const char lua_ident[] =
+  "$Lua: " LUA_RELEASE " " LUA_COPYRIGHT " $\n"
+  "$Authors: " LUA_AUTHORS " $\n"
+  "$URL: www.lua.org $\n";
+
+
+
+#define api_checknelems(L, n)	api_check(L, (n) <= (L->top - L->base))
+
+#define api_checkvalidindex(L, i)	api_check(L, (i) != luaO_nilobject)
+
+#define api_incr_top(L)   {api_check(L, L->top < L->ci->top); L->top++;}
+
+
+
+static TValue *index2adr (lua_State *L, int idx) {
+  if (idx > 0) {
+    TValue *o = L->base + (idx - 1);
+    api_check(L, idx <= L->ci->top - L->base);
+    if (o >= L->top) return cast(TValue *, luaO_nilobject);
+    else return o;
+  }
+  else if (idx > LUA_REGISTRYINDEX) {
+    api_check(L, idx != 0 && -idx <= L->top - L->base);
+    return L->top + idx;
+  }
+  else switch (idx) {  /* pseudo-indices */
+    case LUA_REGISTRYINDEX: return registry(L);
+    case LUA_ENVIRONINDEX: {
+      Closure *func = curr_func(L);
+      sethvalue(L, &L->env, func->c.env);
+      return &L->env;
+    }
+    case LUA_GLOBALSINDEX: return gt(L);
+    default: {
+      Closure *func = curr_func(L);
+      idx = LUA_GLOBALSINDEX - idx;
+      return (idx <= func->c.nupvalues)
+                ? &func->c.upvalue[idx-1]
+                : cast(TValue *, luaO_nilobject);
+    }
+  }
+}
+
+
+static Table *getcurrenv (lua_State *L) {
+  if (L->ci == L->base_ci)  /* no enclosing function? */
+    return hvalue(gt(L));  /* use global table as environment */
+  else {
+    Closure *func = curr_func(L);
+    return func->c.env;
+  }
+}
+
+
+void luaA_pushobject (lua_State *L, const TValue *o) {
+  setobj2s(L, L->top, o);
+  api_incr_top(L);
+}
+
+
+LUA_API int lua_checkstack (lua_State *L, int size) {
+  int res = 1;
+  lua_lock(L);
+  if (size > LUAI_MAXCSTACK || (L->top - L->base + size) > LUAI_MAXCSTACK)
+    res = 0;  /* stack overflow */
+  else if (size > 0) {
+    luaD_checkstack(L, size);
+    if (L->ci->top < L->top + size)
+      L->ci->top = L->top + size;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
+  int i;
+  if (from == to) return;
+  lua_lock(to);
+  api_checknelems(from, n);
+  api_check(from, G(from) == G(to));
+  api_check(from, to->ci->top - to->top >= n);
+  from->top -= n;
+  for (i = 0; i < n; i++) {
+    setobj2s(to, to->top++, from->top + i);
+  }
+  lua_unlock(to);
+}
+
+
+LUA_API void lua_setlevel (lua_State *from, lua_State *to) {
+  to->nCcalls = from->nCcalls;
+}
+
+
+LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
+  lua_CFunction old;
+  lua_lock(L);
+  old = G(L)->panic;
+  G(L)->panic = panicf;
+  lua_unlock(L);
+  return old;
+}
+
+
+LUA_API lua_State *lua_newthread (lua_State *L) {
+  lua_State *L1;
+  lua_lock(L);
+  luaC_checkGC(L);
+  L1 = luaE_newthread(L);
+  setthvalue(L, L->top, L1);
+  api_incr_top(L);
+  lua_unlock(L);
+  luai_userstatethread(L, L1);
+  return L1;
+}
+
+
+
+/*
+** basic stack manipulation
+*/
+
+
+LUA_API int lua_gettop (lua_State *L) {
+  return cast_int(L->top - L->base);
+}
+
+
+LUA_API void lua_settop (lua_State *L, int idx) {
+  lua_lock(L);
+  if (idx >= 0) {
+    api_check(L, idx <= L->stack_last - L->base);
+    while (L->top < L->base + idx)
+      setnilvalue(L->top++);
+    L->top = L->base + idx;
+  }
+  else {
+    api_check(L, -(idx+1) <= (L->top - L->base));
+    L->top += idx+1;  /* `subtract' index (index is negative) */
+  }
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_remove (lua_State *L, int idx) {
+  StkId p;
+  lua_lock(L);
+  p = index2adr(L, idx);
+  api_checkvalidindex(L, p);
+  while (++p < L->top) setobjs2s(L, p-1, p);
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_insert (lua_State *L, int idx) {
+  StkId p;
+  StkId q;
+  lua_lock(L);
+  p = index2adr(L, idx);
+  api_checkvalidindex(L, p);
+  for (q = L->top; q>p; q--) setobjs2s(L, q, q-1);
+  setobjs2s(L, p, L->top);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_replace (lua_State *L, int idx) {
+  StkId o;
+  lua_lock(L);
+  /* explicit test for incompatible code */
+  if (idx == LUA_ENVIRONINDEX && L->ci == L->base_ci)
+    luaG_runerror(L, "no calling environment");
+  api_checknelems(L, 1);
+  o = index2adr(L, idx);
+  api_checkvalidindex(L, o);
+  if (idx == LUA_ENVIRONINDEX) {
+    Closure *func = curr_func(L);
+    api_check(L, ttistable(L->top - 1)); 
+    func->c.env = hvalue(L->top - 1);
+    luaC_barrier(L, func, L->top - 1);
+  }
+  else {
+    setobj(L, o, L->top - 1);
+    if (idx < LUA_GLOBALSINDEX)  /* function upvalue? */
+      luaC_barrier(L, curr_func(L), L->top - 1);
+  }
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushvalue (lua_State *L, int idx) {
+  lua_lock(L);
+  setobj2s(L, L->top, index2adr(L, idx));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+
+/*
+** access functions (stack -> C)
+*/
+
+
+LUA_API int lua_type (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return (o == luaO_nilobject) ? LUA_TNONE : ttype(o);
+}
+
+
+LUA_API const char *lua_typename (lua_State *L, int t) {
+  UNUSED(L);
+  return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
+}
+
+
+LUA_API int lua_iscfunction (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return iscfunction(o);
+}
+
+
+LUA_API int lua_isnumber (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  return tonumber(o, &n);
+}
+
+
+LUA_API int lua_isstring (lua_State *L, int idx) {
+  int t = lua_type(L, idx);
+  return (t == LUA_TSTRING || t == LUA_TNUMBER);
+}
+
+
+LUA_API int lua_isuserdata (lua_State *L, int idx) {
+  const TValue *o = index2adr(L, idx);
+  return (ttisuserdata(o) || ttislightuserdata(o));
+}
+
+
+LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
+  StkId o1 = index2adr(L, index1);
+  StkId o2 = index2adr(L, index2);
+  return (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
+         : luaO_rawequalObj(o1, o2);
+}
+
+
+LUA_API int lua_equal (lua_State *L, int index1, int index2) {
+  StkId o1, o2;
+  int i;
+  lua_lock(L);  /* may call tag method */
+  o1 = index2adr(L, index1);
+  o2 = index2adr(L, index2);
+  i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0 : equalobj(L, o1, o2);
+  lua_unlock(L);
+  return i;
+}
+
+
+LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
+  StkId o1, o2;
+  int i;
+  lua_lock(L);  /* may call tag method */
+  o1 = index2adr(L, index1);
+  o2 = index2adr(L, index2);
+  i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
+       : luaV_lessthan(L, o1, o2);
+  lua_unlock(L);
+  return i;
+}
+
+
+
+LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  if (tonumber(o, &n))
+    return nvalue(o);
+  else
+    return 0;
+}
+
+
+LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  if (tonumber(o, &n)) {
+    lua_Integer res;
+    lua_Number num = nvalue(o);
+    lua_number2integer(res, num);
+    return res;
+  }
+  else
+    return 0;
+}
+
+
+LUA_API int lua_toboolean (lua_State *L, int idx) {
+  const TValue *o = index2adr(L, idx);
+  return !l_isfalse(o);
+}
+
+
+LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
+  StkId o = index2adr(L, idx);
+  if (!ttisstring(o)) {
+    lua_lock(L);  /* `luaV_tostring' may create a new string */
+    if (!luaV_tostring(L, o)) {  /* conversion failed? */
+      if (len != NULL) *len = 0;
+      lua_unlock(L);
+      return NULL;
+    }
+    luaC_checkGC(L);
+    o = index2adr(L, idx);  /* previous call may reallocate the stack */
+    lua_unlock(L);
+  }
+  if (len != NULL) *len = tsvalue(o)->len;
+  return svalue(o);
+}
+
+
+LUA_API size_t lua_objlen (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  switch (ttype(o)) {
+    case LUA_TSTRING: return tsvalue(o)->len;
+    case LUA_TUSERDATA: return uvalue(o)->len;
+    case LUA_TTABLE: return luaH_getn(hvalue(o));
+    case LUA_TNUMBER: {
+      size_t l;
+      lua_lock(L);  /* `luaV_tostring' may create a new string */
+      l = (luaV_tostring(L, o) ? tsvalue(o)->len : 0);
+      lua_unlock(L);
+      return l;
+    }
+    default: return 0;
+  }
+}
+
+
+LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return (!iscfunction(o)) ? NULL : clvalue(o)->c.f;
+}
+
+
+LUA_API void *lua_touserdata (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  switch (ttype(o)) {
+    case LUA_TUSERDATA: return (rawuvalue(o) + 1);
+    case LUA_TLIGHTUSERDATA: return pvalue(o);
+    default: return NULL;
+  }
+}
+
+
+LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return (!ttisthread(o)) ? NULL : thvalue(o);
+}
+
+
+LUA_API const void *lua_topointer (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  switch (ttype(o)) {
+    case LUA_TTABLE: return hvalue(o);
+    case LUA_TFUNCTION: return clvalue(o);
+    case LUA_TTHREAD: return thvalue(o);
+    case LUA_TUSERDATA:
+    case LUA_TLIGHTUSERDATA:
+      return lua_touserdata(L, idx);
+    default: return NULL;
+  }
+}
+
+
+
+/*
+** push functions (C -> stack)
+*/
+
+
+LUA_API void lua_pushnil (lua_State *L) {
+  lua_lock(L);
+  setnilvalue(L->top);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
+  lua_lock(L);
+  setnvalue(L->top, n);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
+  lua_lock(L);
+  setnvalue(L->top, cast_num(n));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  setsvalue2s(L, L->top, luaS_newlstr(L, s, len));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushstring (lua_State *L, const char *s) {
+  if (s == NULL)
+    lua_pushnil(L);
+  else
+    lua_pushlstring(L, s, strlen(s));
+}
+
+
+LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
+                                      va_list argp) {
+  const char *ret;
+  lua_lock(L);
+  luaC_checkGC(L);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
+  const char *ret;
+  va_list argp;
+  lua_lock(L);
+  luaC_checkGC(L);
+  va_start(argp, fmt);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
+  Closure *cl;
+  lua_lock(L);
+  luaC_checkGC(L);
+  api_checknelems(L, n);
+  cl = luaF_newCclosure(L, n, getcurrenv(L));
+  cl->c.f = fn;
+  L->top -= n;
+  while (n--)
+    setobj2n(L, &cl->c.upvalue[n], L->top+n);
+  setclvalue(L, L->top, cl);
+  lua_assert(iswhite(obj2gco(cl)));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushboolean (lua_State *L, int b) {
+  lua_lock(L);
+  setbvalue(L->top, (b != 0));  /* ensure that true is 1 */
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
+  lua_lock(L);
+  setpvalue(L->top, p);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_pushthread (lua_State *L) {
+  lua_lock(L);
+  setthvalue(L, L->top, L);
+  api_incr_top(L);
+  lua_unlock(L);
+  return (G(L)->mainthread == L);
+}
+
+
+
+/*
+** get functions (Lua -> stack)
+*/
+
+
+LUA_API void lua_gettable (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  luaV_gettable(L, t, L->top - 1, L->top - 1);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_getfield (lua_State *L, int idx, const char *k) {
+  StkId t;
+  TValue key;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  setsvalue(L, &key, luaS_new(L, k));
+  luaV_gettable(L, t, &key, L->top);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawget (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_check(L, ttistable(t));
+  setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawgeti (lua_State *L, int idx, int n) {
+  StkId o;
+  lua_lock(L);
+  o = index2adr(L, idx);
+  api_check(L, ttistable(o));
+  setobj2s(L, L->top, luaH_getnum(hvalue(o), n));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  sethvalue(L, L->top, luaH_new(L, narray, nrec));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_getmetatable (lua_State *L, int objindex) {
+  const TValue *obj;
+  Table *mt = NULL;
+  int res;
+  lua_lock(L);
+  obj = index2adr(L, objindex);
+  switch (ttype(obj)) {
+    case LUA_TTABLE:
+      mt = hvalue(obj)->metatable;
+      break;
+    case LUA_TUSERDATA:
+      mt = uvalue(obj)->metatable;
+      break;
+    default:
+      mt = G(L)->mt[ttype(obj)];
+      break;
+  }
+  if (mt == NULL)
+    res = 0;
+  else {
+    sethvalue(L, L->top, mt);
+    api_incr_top(L);
+    res = 1;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_getfenv (lua_State *L, int idx) {
+  StkId o;
+  lua_lock(L);
+  o = index2adr(L, idx);
+  api_checkvalidindex(L, o);
+  switch (ttype(o)) {
+    case LUA_TFUNCTION:
+      sethvalue(L, L->top, clvalue(o)->c.env);
+      break;
+    case LUA_TUSERDATA:
+      sethvalue(L, L->top, uvalue(o)->env);
+      break;
+    case LUA_TTHREAD:
+      setobj2s(L, L->top,  gt(thvalue(o)));
+      break;
+    default:
+      setnilvalue(L->top);
+      break;
+  }
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+/*
+** set functions (stack -> Lua)
+*/
+
+
+LUA_API void lua_settable (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  luaV_settable(L, t, L->top - 2, L->top - 1);
+  L->top -= 2;  /* pop index and value */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
+  StkId t;
+  TValue key;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  setsvalue(L, &key, luaS_new(L, k));
+  luaV_settable(L, t, &key, L->top - 1);
+  L->top--;  /* pop value */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawset (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = index2adr(L, idx);
+  api_check(L, ttistable(t));
+  setobj2t(L, luaH_set(L, hvalue(t), L->top-2), L->top-1);
+  luaC_barriert(L, hvalue(t), L->top-1);
+  L->top -= 2;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawseti (lua_State *L, int idx, int n) {
+  StkId o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = index2adr(L, idx);
+  api_check(L, ttistable(o));
+  setobj2t(L, luaH_setnum(L, hvalue(o), n), L->top-1);
+  luaC_barriert(L, hvalue(o), L->top-1);
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_setmetatable (lua_State *L, int objindex) {
+  TValue *obj;
+  Table *mt;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  obj = index2adr(L, objindex);
+  api_checkvalidindex(L, obj);
+  if (ttisnil(L->top - 1))
+    mt = NULL;
+  else {
+    api_check(L, ttistable(L->top - 1));
+    mt = hvalue(L->top - 1);
+  }
+  switch (ttype(obj)) {
+    case LUA_TTABLE: {
+      hvalue(obj)->metatable = mt;
+      if (mt)
+        luaC_objbarriert(L, hvalue(obj), mt);
+      break;
+    }
+    case LUA_TUSERDATA: {
+      uvalue(obj)->metatable = mt;
+      if (mt)
+        luaC_objbarrier(L, rawuvalue(obj), mt);
+      break;
+    }
+    default: {
+      G(L)->mt[ttype(obj)] = mt;
+      break;
+    }
+  }
+  L->top--;
+  lua_unlock(L);
+  return 1;
+}
+
+
+LUA_API int lua_setfenv (lua_State *L, int idx) {
+  StkId o;
+  int res = 1;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = index2adr(L, idx);
+  api_checkvalidindex(L, o);
+  api_check(L, ttistable(L->top - 1));
+  switch (ttype(o)) {
+    case LUA_TFUNCTION:
+      clvalue(o)->c.env = hvalue(L->top - 1);
+      break;
+    case LUA_TUSERDATA:
+      uvalue(o)->env = hvalue(L->top - 1);
+      break;
+    case LUA_TTHREAD:
+      sethvalue(L, gt(thvalue(o)), hvalue(L->top - 1));
+      break;
+    default:
+      res = 0;
+      break;
+  }
+  if (res) luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
+  L->top--;
+  lua_unlock(L);
+  return res;
+}
+
+
+/*
+** `load' and `call' functions (run Lua code)
+*/
+
+
+#define adjustresults(L,nres) \
+    { if (nres == LUA_MULTRET && L->top >= L->ci->top) L->ci->top = L->top; }
+
+
+#define checkresults(L,na,nr) \
+     api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)))
+	
+
+LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
+  StkId func;
+  lua_lock(L);
+  api_checknelems(L, nargs+1);
+  checkresults(L, nargs, nresults);
+  func = L->top - (nargs+1);
+  luaD_call(L, func, nresults);
+  adjustresults(L, nresults);
+  lua_unlock(L);
+}
+
+
+
+/*
+** Execute a protected call.
+*/
+struct CallS {  /* data to `f_call' */
+  StkId func;
+  int nresults;
+};
+
+
+static void f_call (lua_State *L, void *ud) {
+  struct CallS *c = cast(struct CallS *, ud);
+  luaD_call(L, c->func, c->nresults);
+}
+
+
+
+LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) {
+  struct CallS c;
+  int status;
+  ptrdiff_t func;
+  lua_lock(L);
+  api_checknelems(L, nargs+1);
+  checkresults(L, nargs, nresults);
+  if (errfunc == 0)
+    func = 0;
+  else {
+    StkId o = index2adr(L, errfunc);
+    api_checkvalidindex(L, o);
+    func = savestack(L, o);
+  }
+  c.func = L->top - (nargs+1);  /* function to be called */
+  c.nresults = nresults;
+  status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
+  adjustresults(L, nresults);
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** Execute a protected C call.
+*/
+struct CCallS {  /* data to `f_Ccall' */
+  lua_CFunction func;
+  void *ud;
+};
+
+
+static void f_Ccall (lua_State *L, void *ud) {
+  struct CCallS *c = cast(struct CCallS *, ud);
+  Closure *cl;
+  cl = luaF_newCclosure(L, 0, getcurrenv(L));
+  cl->c.f = c->func;
+  setclvalue(L, L->top, cl);  /* push function */
+  api_incr_top(L);
+  setpvalue(L->top, c->ud);  /* push only argument */
+  api_incr_top(L);
+  luaD_call(L, L->top - 2, 0);
+}
+
+
+LUA_API int lua_cpcall (lua_State *L, lua_CFunction func, void *ud) {
+  struct CCallS c;
+  int status;
+  lua_lock(L);
+  c.func = func;
+  c.ud = ud;
+  status = luaD_pcall(L, f_Ccall, &c, savestack(L, L->top), 0);
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
+                      const char *chunkname) {
+  ZIO z;
+  int status;
+  lua_lock(L);
+  if (!chunkname) chunkname = "?";
+  luaZ_init(L, &z, reader, data);
+  status = luaD_protectedparser(L, &z, chunkname);
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data) {
+  int status;
+  TValue *o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = L->top - 1;
+  if (isLfunction(o))
+    status = luaU_dump(L, clvalue(o)->l.p, writer, data, 0);
+  else
+    status = 1;
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int  lua_status (lua_State *L) {
+  return L->status;
+}
+
+
+/*
+** Garbage-collection function
+*/
+
+LUA_API int lua_gc (lua_State *L, int what, int data) {
+  int res = 0;
+  global_State *g;
+  lua_lock(L);
+  g = G(L);
+  switch (what) {
+    case LUA_GCSTOP: {
+      g->GCthreshold = MAX_LUMEM;
+      break;
+    }
+    case LUA_GCRESTART: {
+      g->GCthreshold = g->totalbytes;
+      break;
+    }
+    case LUA_GCCOLLECT: {
+      luaC_fullgc(L);
+      break;
+    }
+    case LUA_GCCOUNT: {
+      /* GC values are expressed in Kbytes: #bytes/2^10 */
+      res = cast_int(g->totalbytes >> 10);
+      break;
+    }
+    case LUA_GCCOUNTB: {
+      res = cast_int(g->totalbytes & 0x3ff);
+      break;
+    }
+    case LUA_GCSTEP: {
+      lu_mem a = (cast(lu_mem, data) << 10);
+      if (a <= g->totalbytes)
+        g->GCthreshold = g->totalbytes - a;
+      else
+        g->GCthreshold = 0;
+      while (g->GCthreshold <= g->totalbytes) {
+        luaC_step(L);
+        if (g->gcstate == GCSpause) {  /* end of cycle? */
+          res = 1;  /* signal it */
+          break;
+        }
+      }
+      break;
+    }
+    case LUA_GCSETPAUSE: {
+      res = g->gcpause;
+      g->gcpause = data;
+      break;
+    }
+    case LUA_GCSETSTEPMUL: {
+      res = g->gcstepmul;
+      g->gcstepmul = data;
+      break;
+    }
+    default: res = -1;  /* invalid option */
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+
+/*
+** miscellaneous functions
+*/
+
+
+LUA_API int lua_error (lua_State *L) {
+  lua_lock(L);
+  api_checknelems(L, 1);
+  luaG_errormsg(L);
+  lua_unlock(L);
+  return 0;  /* to avoid warnings */
+}
+
+
+LUA_API int lua_next (lua_State *L, int idx) {
+  StkId t;
+  int more;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_check(L, ttistable(t));
+  more = luaH_next(L, hvalue(t), L->top - 1);
+  if (more) {
+    api_incr_top(L);
+  }
+  else  /* no more elements */
+    L->top -= 1;  /* remove key */
+  lua_unlock(L);
+  return more;
+}
+
+
+LUA_API void lua_concat (lua_State *L, int n) {
+  lua_lock(L);
+  api_checknelems(L, n);
+  if (n >= 2) {
+    luaC_checkGC(L);
+    luaV_concat(L, n, cast_int(L->top - L->base) - 1);
+    L->top -= (n-1);
+  }
+  else if (n == 0) {  /* push empty string */
+    setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
+    api_incr_top(L);
+  }
+  /* else n == 1; nothing to do */
+  lua_unlock(L);
+}
+
+
+LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
+  lua_Alloc f;
+  lua_lock(L);
+  if (ud) *ud = G(L)->ud;
+  f = G(L)->frealloc;
+  lua_unlock(L);
+  return f;
+}
+
+
+LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
+  lua_lock(L);
+  G(L)->ud = ud;
+  G(L)->frealloc = f;
+  lua_unlock(L);
+}
+
+
+LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
+  Udata *u;
+  lua_lock(L);
+  luaC_checkGC(L);
+  u = luaS_newudata(L, size, getcurrenv(L));
+  setuvalue(L, L->top, u);
+  api_incr_top(L);
+  lua_unlock(L);
+  return u + 1;
+}
+
+
+
+
+static const char *aux_upvalue (StkId fi, int n, TValue **val) {
+  Closure *f;
+  if (!ttisfunction(fi)) return NULL;
+  f = clvalue(fi);
+  if (f->c.isC) {
+    if (!(1 <= n && n <= f->c.nupvalues)) return NULL;
+    *val = &f->c.upvalue[n-1];
+    return "";
+  }
+  else {
+    Proto *p = f->l.p;
+    if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
+    *val = f->l.upvals[n-1]->v;
+    return getstr(p->upvalues[n-1]);
+  }
+}
+
+
+LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TValue *val;
+  lua_lock(L);
+  name = aux_upvalue(index2adr(L, funcindex), n, &val);
+  if (name) {
+    setobj2s(L, L->top, val);
+    api_incr_top(L);
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TValue *val;
+  StkId fi;
+  lua_lock(L);
+  fi = index2adr(L, funcindex);
+  api_checknelems(L, 1);
+  name = aux_upvalue(fi, n, &val);
+  if (name) {
+    L->top--;
+    setobj(L, val, L->top);
+    luaC_barrier(L, clvalue(fi), L->top);
+  }
+  lua_unlock(L);
+  return name;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lapi.h b/third_party/lua-src/lua-5.1.5/lapi.h
new file mode 100644
index 00000000..2c3fab24
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lapi.h
@@ -0,0 +1,16 @@
+/*
+** $Id: lapi.h,v 2.2.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions from Lua API
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lapi_h
+#define lapi_h
+
+
+#include "lobject.h"
+
+
+LUAI_FUNC void luaA_pushobject (lua_State *L, const TValue *o);
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lauxlib.c b/third_party/lua-src/lua-5.1.5/lauxlib.c
new file mode 100644
index 00000000..10f14e2c
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lauxlib.c
@@ -0,0 +1,652 @@
+/*
+** $Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/* This file uses only the official API of Lua.
+** Any function declared here could be written as an application function.
+*/
+
+#define lauxlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+
+
+#define FREELIST_REF	0	/* free list of references */
+
+
+/* convert a stack index to positive */
+#define abs_index(L, i)		((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
+					lua_gettop(L) + (i) + 1)
+
+
+/*
+** {======================================================
+** Error-report functions
+** =======================================================
+*/
+
+
+LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
+  lua_Debug ar;
+  if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
+    return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
+  lua_getinfo(L, "n", &ar);
+  if (strcmp(ar.namewhat, "method") == 0) {
+    narg--;  /* do not count `self' */
+    if (narg == 0)  /* error is in the self argument itself? */
+      return luaL_error(L, "calling " LUA_QS " on bad self (%s)",
+                           ar.name, extramsg);
+  }
+  if (ar.name == NULL)
+    ar.name = "?";
+  return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
+                        narg, ar.name, extramsg);
+}
+
+
+LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
+  const char *msg = lua_pushfstring(L, "%s expected, got %s",
+                                    tname, luaL_typename(L, narg));
+  return luaL_argerror(L, narg, msg);
+}
+
+
+static void tag_error (lua_State *L, int narg, int tag) {
+  luaL_typerror(L, narg, lua_typename(L, tag));
+}
+
+
+LUALIB_API void luaL_where (lua_State *L, int level) {
+  lua_Debug ar;
+  if (lua_getstack(L, level, &ar)) {  /* check function at level */
+    lua_getinfo(L, "Sl", &ar);  /* get info about it */
+    if (ar.currentline > 0) {  /* is there info? */
+      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
+      return;
+    }
+  }
+  lua_pushliteral(L, "");  /* else, no information available... */
+}
+
+
+LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  luaL_where(L, 1);
+  lua_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_concat(L, 2);
+  return lua_error(L);
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def,
+                                 const char *const lst[]) {
+  const char *name = (def) ? luaL_optstring(L, narg, def) :
+                             luaL_checkstring(L, narg);
+  int i;
+  for (i=0; lst[i]; i++)
+    if (strcmp(lst[i], name) == 0)
+      return i;
+  return luaL_argerror(L, narg,
+                       lua_pushfstring(L, "invalid option " LUA_QS, name));
+}
+
+
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+  lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get registry.name */
+  if (!lua_isnil(L, -1))  /* name already in use? */
+    return 0;  /* leave previous value on top, but return 0 */
+  lua_pop(L, 1);
+  lua_newtable(L);  /* create metatable */
+  lua_pushvalue(L, -1);
+  lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
+  return 1;
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+  void *p = lua_touserdata(L, ud);
+  if (p != NULL) {  /* value is a userdata? */
+    if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
+      lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get correct metatable */
+      if (lua_rawequal(L, -1, -2)) {  /* does it have the correct mt? */
+        lua_pop(L, 2);  /* remove both metatables */
+        return p;
+      }
+    }
+  }
+  luaL_typerror(L, ud, tname);  /* else error */
+  return NULL;  /* to avoid warnings */
+}
+
+
+LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
+  if (!lua_checkstack(L, space))
+    luaL_error(L, "stack overflow (%s)", mes);
+}
+
+
+LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
+  if (lua_type(L, narg) != t)
+    tag_error(L, narg, t);
+}
+
+
+LUALIB_API void luaL_checkany (lua_State *L, int narg) {
+  if (lua_type(L, narg) == LUA_TNONE)
+    luaL_argerror(L, narg, "value expected");
+}
+
+
+LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
+  const char *s = lua_tolstring(L, narg, len);
+  if (!s) tag_error(L, narg, LUA_TSTRING);
+  return s;
+}
+
+
+LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
+                                        const char *def, size_t *len) {
+  if (lua_isnoneornil(L, narg)) {
+    if (len)
+      *len = (def ? strlen(def) : 0);
+    return def;
+  }
+  else return luaL_checklstring(L, narg, len);
+}
+
+
+LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
+  lua_Number d = lua_tonumber(L, narg);
+  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
+    tag_error(L, narg, LUA_TNUMBER);
+  return d;
+}
+
+
+LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
+  return luaL_opt(L, luaL_checknumber, narg, def);
+}
+
+
+LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
+  lua_Integer d = lua_tointeger(L, narg);
+  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
+    tag_error(L, narg, LUA_TNUMBER);
+  return d;
+}
+
+
+LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
+                                                      lua_Integer def) {
+  return luaL_opt(L, luaL_checkinteger, narg, def);
+}
+
+
+LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
+  if (!lua_getmetatable(L, obj))  /* no metatable? */
+    return 0;
+  lua_pushstring(L, event);
+  lua_rawget(L, -2);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 2);  /* remove metatable and metafield */
+    return 0;
+  }
+  else {
+    lua_remove(L, -2);  /* remove only metatable */
+    return 1;
+  }
+}
+
+
+LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
+  obj = abs_index(L, obj);
+  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
+    return 0;
+  lua_pushvalue(L, obj);
+  lua_call(L, 1, 1);
+  return 1;
+}
+
+
+LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
+                                const luaL_Reg *l) {
+  luaI_openlib(L, libname, l, 0);
+}
+
+
+static int libsize (const luaL_Reg *l) {
+  int size = 0;
+  for (; l->name; l++) size++;
+  return size;
+}
+
+
+LUALIB_API void luaI_openlib (lua_State *L, const char *libname,
+                              const luaL_Reg *l, int nup) {
+  if (libname) {
+    int size = libsize(l);
+    /* check whether lib already exists */
+    luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);
+    lua_getfield(L, -1, libname);  /* get _LOADED[libname] */
+    if (!lua_istable(L, -1)) {  /* not found? */
+      lua_pop(L, 1);  /* remove previous result */
+      /* try global variable (and create one if it does not exist) */
+      if (luaL_findtable(L, LUA_GLOBALSINDEX, libname, size) != NULL)
+        luaL_error(L, "name conflict for module " LUA_QS, libname);
+      lua_pushvalue(L, -1);
+      lua_setfield(L, -3, libname);  /* _LOADED[libname] = new table */
+    }
+    lua_remove(L, -2);  /* remove _LOADED table */
+    lua_insert(L, -(nup+1));  /* move library table to below upvalues */
+  }
+  for (; l->name; l++) {
+    int i;
+    for (i=0; i<nup; i++)  /* copy upvalues to the top */
+      lua_pushvalue(L, -nup);
+    lua_pushcclosure(L, l->func, nup);
+    lua_setfield(L, -(nup+2), l->name);
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+
+/*
+** {======================================================
+** getn-setn: size for arrays
+** =======================================================
+*/
+
+#if defined(LUA_COMPAT_GETN)
+
+static int checkint (lua_State *L, int topop) {
+  int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1;
+  lua_pop(L, topop);
+  return n;
+}
+
+
+static void getsizes (lua_State *L) {
+  lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");
+  if (lua_isnil(L, -1)) {  /* no `size' table? */
+    lua_pop(L, 1);  /* remove nil */
+    lua_newtable(L);  /* create it */
+    lua_pushvalue(L, -1);  /* `size' will be its own metatable */
+    lua_setmetatable(L, -2);
+    lua_pushliteral(L, "kv");
+    lua_setfield(L, -2, "__mode");  /* metatable(N).__mode = "kv" */
+    lua_pushvalue(L, -1);
+    lua_setfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");  /* store in register */
+  }
+}
+
+
+LUALIB_API void luaL_setn (lua_State *L, int t, int n) {
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");
+  lua_rawget(L, t);
+  if (checkint(L, 1) >= 0) {  /* is there a numeric field `n'? */
+    lua_pushliteral(L, "n");  /* use it */
+    lua_pushinteger(L, n);
+    lua_rawset(L, t);
+  }
+  else {  /* use `sizes' */
+    getsizes(L);
+    lua_pushvalue(L, t);
+    lua_pushinteger(L, n);
+    lua_rawset(L, -3);  /* sizes[t] = n */
+    lua_pop(L, 1);  /* remove `sizes' */
+  }
+}
+
+
+LUALIB_API int luaL_getn (lua_State *L, int t) {
+  int n;
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");  /* try t.n */
+  lua_rawget(L, t);
+  if ((n = checkint(L, 1)) >= 0) return n;
+  getsizes(L);  /* else try sizes[t] */
+  lua_pushvalue(L, t);
+  lua_rawget(L, -2);
+  if ((n = checkint(L, 2)) >= 0) return n;
+  return (int)lua_objlen(L, t);
+}
+
+#endif
+
+/* }====================================================== */
+
+
+
+LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
+                                                               const char *r) {
+  const char *wild;
+  size_t l = strlen(p);
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  while ((wild = strstr(s, p)) != NULL) {
+    luaL_addlstring(&b, s, wild - s);  /* push prefix */
+    luaL_addstring(&b, r);  /* push replacement in place of pattern */
+    s = wild + l;  /* continue after `p' */
+  }
+  luaL_addstring(&b, s);  /* push last suffix */
+  luaL_pushresult(&b);
+  return lua_tostring(L, -1);
+}
+
+
+LUALIB_API const char *luaL_findtable (lua_State *L, int idx,
+                                       const char *fname, int szhint) {
+  const char *e;
+  lua_pushvalue(L, idx);
+  do {
+    e = strchr(fname, '.');
+    if (e == NULL) e = fname + strlen(fname);
+    lua_pushlstring(L, fname, e - fname);
+    lua_rawget(L, -2);
+    if (lua_isnil(L, -1)) {  /* no such field? */
+      lua_pop(L, 1);  /* remove this nil */
+      lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
+      lua_pushlstring(L, fname, e - fname);
+      lua_pushvalue(L, -2);
+      lua_settable(L, -4);  /* set new table into field */
+    }
+    else if (!lua_istable(L, -1)) {  /* field has a non-table value? */
+      lua_pop(L, 2);  /* remove table and value */
+      return fname;  /* return problematic part of the name */
+    }
+    lua_remove(L, -2);  /* remove previous table */
+    fname = e + 1;
+  } while (*e == '.');
+  return NULL;
+}
+
+
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+
+#define bufflen(B)	((B)->p - (B)->buffer)
+#define bufffree(B)	((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
+
+#define LIMIT	(LUA_MINSTACK/2)
+
+
+static int emptybuffer (luaL_Buffer *B) {
+  size_t l = bufflen(B);
+  if (l == 0) return 0;  /* put nothing on stack */
+  else {
+    lua_pushlstring(B->L, B->buffer, l);
+    B->p = B->buffer;
+    B->lvl++;
+    return 1;
+  }
+}
+
+
+static void adjuststack (luaL_Buffer *B) {
+  if (B->lvl > 1) {
+    lua_State *L = B->L;
+    int toget = 1;  /* number of levels to concat */
+    size_t toplen = lua_strlen(L, -1);
+    do {
+      size_t l = lua_strlen(L, -(toget+1));
+      if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
+        toplen += l;
+        toget++;
+      }
+      else break;
+    } while (toget < B->lvl);
+    lua_concat(L, toget);
+    B->lvl = B->lvl - toget + 1;
+  }
+}
+
+
+LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
+  if (emptybuffer(B))
+    adjuststack(B);
+  return B->buffer;
+}
+
+
+LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
+  while (l--)
+    luaL_addchar(B, *s++);
+}
+
+
+LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
+  luaL_addlstring(B, s, strlen(s));
+}
+
+
+LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
+  emptybuffer(B);
+  lua_concat(B->L, B->lvl);
+  B->lvl = 1;
+}
+
+
+LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
+  lua_State *L = B->L;
+  size_t vl;
+  const char *s = lua_tolstring(L, -1, &vl);
+  if (vl <= bufffree(B)) {  /* fit into buffer? */
+    memcpy(B->p, s, vl);  /* put it there */
+    B->p += vl;
+    lua_pop(L, 1);  /* remove from stack */
+  }
+  else {
+    if (emptybuffer(B))
+      lua_insert(L, -2);  /* put buffer before new value */
+    B->lvl++;  /* add new value into B stack */
+    adjuststack(B);
+  }
+}
+
+
+LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
+  B->L = L;
+  B->p = B->buffer;
+  B->lvl = 0;
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_ref (lua_State *L, int t) {
+  int ref;
+  t = abs_index(L, t);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 1);  /* remove from stack */
+    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
+  }
+  lua_rawgeti(L, t, FREELIST_REF);  /* get first free element */
+  ref = (int)lua_tointeger(L, -1);  /* ref = t[FREELIST_REF] */
+  lua_pop(L, 1);  /* remove it from stack */
+  if (ref != 0) {  /* any free element? */
+    lua_rawgeti(L, t, ref);  /* remove it from list */
+    lua_rawseti(L, t, FREELIST_REF);  /* (t[FREELIST_REF] = t[ref]) */
+  }
+  else {  /* no free elements */
+    ref = (int)lua_objlen(L, t);
+    ref++;  /* create new reference */
+  }
+  lua_rawseti(L, t, ref);
+  return ref;
+}
+
+
+LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
+  if (ref >= 0) {
+    t = abs_index(L, t);
+    lua_rawgeti(L, t, FREELIST_REF);
+    lua_rawseti(L, t, ref);  /* t[ref] = t[FREELIST_REF] */
+    lua_pushinteger(L, ref);
+    lua_rawseti(L, t, FREELIST_REF);  /* t[FREELIST_REF] = ref */
+  }
+}
+
+
+
+/*
+** {======================================================
+** Load functions
+** =======================================================
+*/
+
+typedef struct LoadF {
+  int extraline;
+  FILE *f;
+  char buff[LUAL_BUFFERSIZE];
+} LoadF;
+
+
+static const char *getF (lua_State *L, void *ud, size_t *size) {
+  LoadF *lf = (LoadF *)ud;
+  (void)L;
+  if (lf->extraline) {
+    lf->extraline = 0;
+    *size = 1;
+    return "\n";
+  }
+  if (feof(lf->f)) return NULL;
+  *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
+  return (*size > 0) ? lf->buff : NULL;
+}
+
+
+static int errfile (lua_State *L, const char *what, int fnameindex) {
+  const char *serr = strerror(errno);
+  const char *filename = lua_tostring(L, fnameindex) + 1;
+  lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr);
+  lua_remove(L, fnameindex);
+  return LUA_ERRFILE;
+}
+
+
+LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
+  LoadF lf;
+  int status, readstatus;
+  int c;
+  int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
+  lf.extraline = 0;
+  if (filename == NULL) {
+    lua_pushliteral(L, "=stdin");
+    lf.f = stdin;
+  }
+  else {
+    lua_pushfstring(L, "@%s", filename);
+    lf.f = fopen(filename, "r");
+    if (lf.f == NULL) return errfile(L, "open", fnameindex);
+  }
+  c = getc(lf.f);
+  if (c == '#') {  /* Unix exec. file? */
+    lf.extraline = 1;
+    while ((c = getc(lf.f)) != EOF && c != '\n') ;  /* skip first line */
+    if (c == '\n') c = getc(lf.f);
+  }
+  if (c == LUA_SIGNATURE[0] && filename) {  /* binary file? */
+    lf.f = freopen(filename, "rb", lf.f);  /* reopen in binary mode */
+    if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
+    /* skip eventual `#!...' */
+   while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ;
+    lf.extraline = 0;
+  }
+  ungetc(c, lf.f);
+  status = lua_load(L, getF, &lf, lua_tostring(L, -1));
+  readstatus = ferror(lf.f);
+  if (filename) fclose(lf.f);  /* close file (even in case of errors) */
+  if (readstatus) {
+    lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
+    return errfile(L, "read", fnameindex);
+  }
+  lua_remove(L, fnameindex);
+  return status;
+}
+
+
+typedef struct LoadS {
+  const char *s;
+  size_t size;
+} LoadS;
+
+
+static const char *getS (lua_State *L, void *ud, size_t *size) {
+  LoadS *ls = (LoadS *)ud;
+  (void)L;
+  if (ls->size == 0) return NULL;
+  *size = ls->size;
+  ls->size = 0;
+  return ls->s;
+}
+
+
+LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
+                                const char *name) {
+  LoadS ls;
+  ls.s = buff;
+  ls.size = size;
+  return lua_load(L, getS, &ls, name);
+}
+
+
+LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) {
+  return luaL_loadbuffer(L, s, strlen(s), s);
+}
+
+
+
+/* }====================================================== */
+
+
+static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
+  (void)ud;
+  (void)osize;
+  if (nsize == 0) {
+    free(ptr);
+    return NULL;
+  }
+  else
+    return realloc(ptr, nsize);
+}
+
+
+static int panic (lua_State *L) {
+  (void)L;  /* to avoid warnings */
+  fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n",
+                   lua_tostring(L, -1));
+  return 0;
+}
+
+
+LUALIB_API lua_State *luaL_newstate (void) {
+  lua_State *L = lua_newstate(l_alloc, NULL);
+  if (L) lua_atpanic(L, &panic);
+  return L;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lauxlib.h b/third_party/lua-src/lua-5.1.5/lauxlib.h
new file mode 100644
index 00000000..34258235
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lauxlib.h
@@ -0,0 +1,174 @@
+/*
+** $Id: lauxlib.h,v 1.88.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lauxlib_h
+#define lauxlib_h
+
+
+#include <stddef.h>
+#include <stdio.h>
+
+#include "lua.h"
+
+
+#if defined(LUA_COMPAT_GETN)
+LUALIB_API int (luaL_getn) (lua_State *L, int t);
+LUALIB_API void (luaL_setn) (lua_State *L, int t, int n);
+#else
+#define luaL_getn(L,i)          ((int)lua_objlen(L, i))
+#define luaL_setn(L,i,j)        ((void)0)  /* no op! */
+#endif
+
+#if defined(LUA_COMPAT_OPENLIB)
+#define luaI_openlib	luaL_openlib
+#endif
+
+
+/* extra error code for `luaL_load' */
+#define LUA_ERRFILE     (LUA_ERRERR+1)
+
+
+typedef struct luaL_Reg {
+  const char *name;
+  lua_CFunction func;
+} luaL_Reg;
+
+
+
+LUALIB_API void (luaI_openlib) (lua_State *L, const char *libname,
+                                const luaL_Reg *l, int nup);
+LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
+                                const luaL_Reg *l);
+LUALIB_API int (luaL_getmetafield) (lua_State *L, int obj, const char *e);
+LUALIB_API int (luaL_callmeta) (lua_State *L, int obj, const char *e);
+LUALIB_API int (luaL_typerror) (lua_State *L, int narg, const char *tname);
+LUALIB_API int (luaL_argerror) (lua_State *L, int numarg, const char *extramsg);
+LUALIB_API const char *(luaL_checklstring) (lua_State *L, int numArg,
+                                                          size_t *l);
+LUALIB_API const char *(luaL_optlstring) (lua_State *L, int numArg,
+                                          const char *def, size_t *l);
+LUALIB_API lua_Number (luaL_checknumber) (lua_State *L, int numArg);
+LUALIB_API lua_Number (luaL_optnumber) (lua_State *L, int nArg, lua_Number def);
+
+LUALIB_API lua_Integer (luaL_checkinteger) (lua_State *L, int numArg);
+LUALIB_API lua_Integer (luaL_optinteger) (lua_State *L, int nArg,
+                                          lua_Integer def);
+
+LUALIB_API void (luaL_checkstack) (lua_State *L, int sz, const char *msg);
+LUALIB_API void (luaL_checktype) (lua_State *L, int narg, int t);
+LUALIB_API void (luaL_checkany) (lua_State *L, int narg);
+
+LUALIB_API int   (luaL_newmetatable) (lua_State *L, const char *tname);
+LUALIB_API void *(luaL_checkudata) (lua_State *L, int ud, const char *tname);
+
+LUALIB_API void (luaL_where) (lua_State *L, int lvl);
+LUALIB_API int (luaL_error) (lua_State *L, const char *fmt, ...);
+
+LUALIB_API int (luaL_checkoption) (lua_State *L, int narg, const char *def,
+                                   const char *const lst[]);
+
+LUALIB_API int (luaL_ref) (lua_State *L, int t);
+LUALIB_API void (luaL_unref) (lua_State *L, int t, int ref);
+
+LUALIB_API int (luaL_loadfile) (lua_State *L, const char *filename);
+LUALIB_API int (luaL_loadbuffer) (lua_State *L, const char *buff, size_t sz,
+                                  const char *name);
+LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s);
+
+LUALIB_API lua_State *(luaL_newstate) (void);
+
+
+LUALIB_API const char *(luaL_gsub) (lua_State *L, const char *s, const char *p,
+                                                  const char *r);
+
+LUALIB_API const char *(luaL_findtable) (lua_State *L, int idx,
+                                         const char *fname, int szhint);
+
+
+
+
+/*
+** ===============================================================
+** some useful macros
+** ===============================================================
+*/
+
+#define luaL_argcheck(L, cond,numarg,extramsg)	\
+		((void)((cond) || luaL_argerror(L, (numarg), (extramsg))))
+#define luaL_checkstring(L,n)	(luaL_checklstring(L, (n), NULL))
+#define luaL_optstring(L,n,d)	(luaL_optlstring(L, (n), (d), NULL))
+#define luaL_checkint(L,n)	((int)luaL_checkinteger(L, (n)))
+#define luaL_optint(L,n,d)	((int)luaL_optinteger(L, (n), (d)))
+#define luaL_checklong(L,n)	((long)luaL_checkinteger(L, (n)))
+#define luaL_optlong(L,n,d)	((long)luaL_optinteger(L, (n), (d)))
+
+#define luaL_typename(L,i)	lua_typename(L, lua_type(L,(i)))
+
+#define luaL_dofile(L, fn) \
+	(luaL_loadfile(L, fn) || lua_pcall(L, 0, LUA_MULTRET, 0))
+
+#define luaL_dostring(L, s) \
+	(luaL_loadstring(L, s) || lua_pcall(L, 0, LUA_MULTRET, 0))
+
+#define luaL_getmetatable(L,n)	(lua_getfield(L, LUA_REGISTRYINDEX, (n)))
+
+#define luaL_opt(L,f,n,d)	(lua_isnoneornil(L,(n)) ? (d) : f(L,(n)))
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+
+
+typedef struct luaL_Buffer {
+  char *p;			/* current position in buffer */
+  int lvl;  /* number of strings in the stack (level) */
+  lua_State *L;
+  char buffer[LUAL_BUFFERSIZE];
+} luaL_Buffer;
+
+#define luaL_addchar(B,c) \
+  ((void)((B)->p < ((B)->buffer+LUAL_BUFFERSIZE) || luaL_prepbuffer(B)), \
+   (*(B)->p++ = (char)(c)))
+
+/* compatibility only */
+#define luaL_putchar(B,c)	luaL_addchar(B,c)
+
+#define luaL_addsize(B,n)	((B)->p += (n))
+
+LUALIB_API void (luaL_buffinit) (lua_State *L, luaL_Buffer *B);
+LUALIB_API char *(luaL_prepbuffer) (luaL_Buffer *B);
+LUALIB_API void (luaL_addlstring) (luaL_Buffer *B, const char *s, size_t l);
+LUALIB_API void (luaL_addstring) (luaL_Buffer *B, const char *s);
+LUALIB_API void (luaL_addvalue) (luaL_Buffer *B);
+LUALIB_API void (luaL_pushresult) (luaL_Buffer *B);
+
+
+/* }====================================================== */
+
+
+/* compatibility with ref system */
+
+/* pre-defined references */
+#define LUA_NOREF       (-2)
+#define LUA_REFNIL      (-1)
+
+#define lua_ref(L,lock) ((lock) ? luaL_ref(L, LUA_REGISTRYINDEX) : \
+      (lua_pushstring(L, "unlocked references are obsolete"), lua_error(L), 0))
+
+#define lua_unref(L,ref)        luaL_unref(L, LUA_REGISTRYINDEX, (ref))
+
+#define lua_getref(L,ref)       lua_rawgeti(L, LUA_REGISTRYINDEX, (ref))
+
+
+#define luaL_reg	luaL_Reg
+
+#endif
+
+
diff --git a/third_party/lua-src/lua-5.1.5/lbaselib.c b/third_party/lua-src/lua-5.1.5/lbaselib.c
new file mode 100644
index 00000000..2ab550bd
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lbaselib.c
@@ -0,0 +1,653 @@
+/*
+** $Id: lbaselib.c,v 1.191.1.6 2008/02/14 16:46:22 roberto Exp $
+** Basic library
+** See Copyright Notice in lua.h
+*/
+
+
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lbaselib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+
+/*
+** If your system does not support `stdout', you can just remove this function.
+** If you need, you can define your own `print' function, following this
+** model but changing `fputs' to put the strings at a proper place
+** (a console window or a log file, for instance).
+*/
+static int luaB_print (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  lua_getglobal(L, "tostring");
+  for (i=1; i<=n; i++) {
+    const char *s;
+    lua_pushvalue(L, -1);  /* function to be called */
+    lua_pushvalue(L, i);   /* value to print */
+    lua_call(L, 1, 1);
+    s = lua_tostring(L, -1);  /* get result */
+    if (s == NULL)
+      return luaL_error(L, LUA_QL("tostring") " must return a string to "
+                           LUA_QL("print"));
+    if (i>1) fputs("\t", stdout);
+    fputs(s, stdout);
+    lua_pop(L, 1);  /* pop result */
+  }
+  fputs("\n", stdout);
+  return 0;
+}
+
+
+static int luaB_tonumber (lua_State *L) {
+  int base = luaL_optint(L, 2, 10);
+  if (base == 10) {  /* standard conversion */
+    luaL_checkany(L, 1);
+    if (lua_isnumber(L, 1)) {
+      lua_pushnumber(L, lua_tonumber(L, 1));
+      return 1;
+    }
+  }
+  else {
+    const char *s1 = luaL_checkstring(L, 1);
+    char *s2;
+    unsigned long n;
+    luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
+    n = strtoul(s1, &s2, base);
+    if (s1 != s2) {  /* at least one valid digit? */
+      while (isspace((unsigned char)(*s2))) s2++;  /* skip trailing spaces */
+      if (*s2 == '\0') {  /* no invalid trailing characters? */
+        lua_pushnumber(L, (lua_Number)n);
+        return 1;
+      }
+    }
+  }
+  lua_pushnil(L);  /* else not a number */
+  return 1;
+}
+
+
+static int luaB_error (lua_State *L) {
+  int level = luaL_optint(L, 2, 1);
+  lua_settop(L, 1);
+  if (lua_isstring(L, 1) && level > 0) {  /* add extra information? */
+    luaL_where(L, level);
+    lua_pushvalue(L, 1);
+    lua_concat(L, 2);
+  }
+  return lua_error(L);
+}
+
+
+static int luaB_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);
+    return 1;  /* no metatable */
+  }
+  luaL_getmetafield(L, 1, "__metatable");
+  return 1;  /* returns either __metatable field (if present) or metatable */
+}
+
+
+static int luaB_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
+                    "nil or table expected");
+  if (luaL_getmetafield(L, 1, "__metatable"))
+    luaL_error(L, "cannot change a protected metatable");
+  lua_settop(L, 2);
+  lua_setmetatable(L, 1);
+  return 1;
+}
+
+
+static void getfunc (lua_State *L, int opt) {
+  if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);
+  else {
+    lua_Debug ar;
+    int level = opt ? luaL_optint(L, 1, 1) : luaL_checkint(L, 1);
+    luaL_argcheck(L, level >= 0, 1, "level must be non-negative");
+    if (lua_getstack(L, level, &ar) == 0)
+      luaL_argerror(L, 1, "invalid level");
+    lua_getinfo(L, "f", &ar);
+    if (lua_isnil(L, -1))
+      luaL_error(L, "no function environment for tail call at level %d",
+                    level);
+  }
+}
+
+
+static int luaB_getfenv (lua_State *L) {
+  getfunc(L, 1);
+  if (lua_iscfunction(L, -1))  /* is a C function? */
+    lua_pushvalue(L, LUA_GLOBALSINDEX);  /* return the thread's global env. */
+  else
+    lua_getfenv(L, -1);
+  return 1;
+}
+
+
+static int luaB_setfenv (lua_State *L) {
+  luaL_checktype(L, 2, LUA_TTABLE);
+  getfunc(L, 0);
+  lua_pushvalue(L, 2);
+  if (lua_isnumber(L, 1) && lua_tonumber(L, 1) == 0) {
+    /* change environment of current thread */
+    lua_pushthread(L);
+    lua_insert(L, -2);
+    lua_setfenv(L, -2);
+    return 0;
+  }
+  else if (lua_iscfunction(L, -2) || lua_setfenv(L, -2) == 0)
+    luaL_error(L,
+          LUA_QL("setfenv") " cannot change environment of given object");
+  return 1;
+}
+
+
+static int luaB_rawequal (lua_State *L) {
+  luaL_checkany(L, 1);
+  luaL_checkany(L, 2);
+  lua_pushboolean(L, lua_rawequal(L, 1, 2));
+  return 1;
+}
+
+
+static int luaB_rawget (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  lua_rawget(L, 1);
+  return 1;
+}
+
+static int luaB_rawset (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  luaL_checkany(L, 3);
+  lua_settop(L, 3);
+  lua_rawset(L, 1);
+  return 1;
+}
+
+
+static int luaB_gcinfo (lua_State *L) {
+  lua_pushinteger(L, lua_getgccount(L));
+  return 1;
+}
+
+
+static int luaB_collectgarbage (lua_State *L) {
+  static const char *const opts[] = {"stop", "restart", "collect",
+    "count", "step", "setpause", "setstepmul", NULL};
+  static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
+    LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL};
+  int o = luaL_checkoption(L, 1, "collect", opts);
+  int ex = luaL_optint(L, 2, 0);
+  int res = lua_gc(L, optsnum[o], ex);
+  switch (optsnum[o]) {
+    case LUA_GCCOUNT: {
+      int b = lua_gc(L, LUA_GCCOUNTB, 0);
+      lua_pushnumber(L, res + ((lua_Number)b/1024));
+      return 1;
+    }
+    case LUA_GCSTEP: {
+      lua_pushboolean(L, res);
+      return 1;
+    }
+    default: {
+      lua_pushnumber(L, res);
+      return 1;
+    }
+  }
+}
+
+
+static int luaB_type (lua_State *L) {
+  luaL_checkany(L, 1);
+  lua_pushstring(L, luaL_typename(L, 1));
+  return 1;
+}
+
+
+static int luaB_next (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_settop(L, 2);  /* create a 2nd argument if there isn't one */
+  if (lua_next(L, 1))
+    return 2;
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int luaB_pairs (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */
+  lua_pushvalue(L, 1);  /* state, */
+  lua_pushnil(L);  /* and initial value */
+  return 3;
+}
+
+
+static int ipairsaux (lua_State *L) {
+  int i = luaL_checkint(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i++;  /* next value */
+  lua_pushinteger(L, i);
+  lua_rawgeti(L, 1, i);
+  return (lua_isnil(L, -1)) ? 0 : 2;
+}
+
+
+static int luaB_ipairs (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */
+  lua_pushvalue(L, 1);  /* state, */
+  lua_pushinteger(L, 0);  /* and initial value */
+  return 3;
+}
+
+
+static int load_aux (lua_State *L, int status) {
+  if (status == 0)  /* OK? */
+    return 1;
+  else {
+    lua_pushnil(L);
+    lua_insert(L, -2);  /* put before error message */
+    return 2;  /* return nil plus error message */
+  }
+}
+
+
+static int luaB_loadstring (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  const char *chunkname = luaL_optstring(L, 2, s);
+  return load_aux(L, luaL_loadbuffer(L, s, l, chunkname));
+}
+
+
+static int luaB_loadfile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  return load_aux(L, luaL_loadfile(L, fname));
+}
+
+
+/*
+** Reader for generic `load' function: `lua_load' uses the
+** stack for internal stuff, so the reader cannot change the
+** stack top. Instead, it keeps its resulting string in a
+** reserved slot inside the stack.
+*/
+static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
+  (void)ud;  /* to avoid warnings */
+  luaL_checkstack(L, 2, "too many nested functions");
+  lua_pushvalue(L, 1);  /* get function */
+  lua_call(L, 0, 1);  /* call it */
+  if (lua_isnil(L, -1)) {
+    *size = 0;
+    return NULL;
+  }
+  else if (lua_isstring(L, -1)) {
+    lua_replace(L, 3);  /* save string in a reserved stack slot */
+    return lua_tolstring(L, 3, size);
+  }
+  else luaL_error(L, "reader function must return a string");
+  return NULL;  /* to avoid warnings */
+}
+
+
+static int luaB_load (lua_State *L) {
+  int status;
+  const char *cname = luaL_optstring(L, 2, "=(load)");
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  lua_settop(L, 3);  /* function, eventual name, plus one reserved slot */
+  status = lua_load(L, generic_reader, NULL, cname);
+  return load_aux(L, status);
+}
+
+
+static int luaB_dofile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  int n = lua_gettop(L);
+  if (luaL_loadfile(L, fname) != 0) lua_error(L);
+  lua_call(L, 0, LUA_MULTRET);
+  return lua_gettop(L) - n;
+}
+
+
+static int luaB_assert (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_toboolean(L, 1))
+    return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!"));
+  return lua_gettop(L);
+}
+
+
+static int luaB_unpack (lua_State *L) {
+  int i, e, n;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i = luaL_optint(L, 2, 1);
+  e = luaL_opt(L, luaL_checkint, 3, luaL_getn(L, 1));
+  if (i > e) return 0;  /* empty range */
+  n = e - i + 1;  /* number of elements */
+  if (n <= 0 || !lua_checkstack(L, n))  /* n <= 0 means arith. overflow */
+    return luaL_error(L, "too many results to unpack");
+  lua_rawgeti(L, 1, i);  /* push arg[i] (avoiding overflow problems) */
+  while (i++ < e)  /* push arg[i + 1...e] */
+    lua_rawgeti(L, 1, i);
+  return n;
+}
+
+
+static int luaB_select (lua_State *L) {
+  int n = lua_gettop(L);
+  if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
+    lua_pushinteger(L, n-1);
+    return 1;
+  }
+  else {
+    int i = luaL_checkint(L, 1);
+    if (i < 0) i = n + i;
+    else if (i > n) i = n;
+    luaL_argcheck(L, 1 <= i, 1, "index out of range");
+    return n - i;
+  }
+}
+
+
+static int luaB_pcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 1);
+  status = lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0);
+  lua_pushboolean(L, (status == 0));
+  lua_insert(L, 1);
+  return lua_gettop(L);  /* return status + all results */
+}
+
+
+static int luaB_xpcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  lua_insert(L, 1);  /* put error function under function to be called */
+  status = lua_pcall(L, 0, LUA_MULTRET, 1);
+  lua_pushboolean(L, (status == 0));
+  lua_replace(L, 1);
+  return lua_gettop(L);  /* return status + all results */
+}
+
+
+static int luaB_tostring (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (luaL_callmeta(L, 1, "__tostring"))  /* is there a metafield? */
+    return 1;  /* use its value */
+  switch (lua_type(L, 1)) {
+    case LUA_TNUMBER:
+      lua_pushstring(L, lua_tostring(L, 1));
+      break;
+    case LUA_TSTRING:
+      lua_pushvalue(L, 1);
+      break;
+    case LUA_TBOOLEAN:
+      lua_pushstring(L, (lua_toboolean(L, 1) ? "true" : "false"));
+      break;
+    case LUA_TNIL:
+      lua_pushliteral(L, "nil");
+      break;
+    default:
+      lua_pushfstring(L, "%s: %p", luaL_typename(L, 1), lua_topointer(L, 1));
+      break;
+  }
+  return 1;
+}
+
+
+static int luaB_newproxy (lua_State *L) {
+  lua_settop(L, 1);
+  lua_newuserdata(L, 0);  /* create proxy */
+  if (lua_toboolean(L, 1) == 0)
+    return 1;  /* no metatable */
+  else if (lua_isboolean(L, 1)) {
+    lua_newtable(L);  /* create a new metatable `m' ... */
+    lua_pushvalue(L, -1);  /* ... and mark `m' as a valid metatable */
+    lua_pushboolean(L, 1);
+    lua_rawset(L, lua_upvalueindex(1));  /* weaktable[m] = true */
+  }
+  else {
+    int validproxy = 0;  /* to check if weaktable[metatable(u)] == true */
+    if (lua_getmetatable(L, 1)) {
+      lua_rawget(L, lua_upvalueindex(1));
+      validproxy = lua_toboolean(L, -1);
+      lua_pop(L, 1);  /* remove value */
+    }
+    luaL_argcheck(L, validproxy, 1, "boolean or proxy expected");
+    lua_getmetatable(L, 1);  /* metatable is valid; get it */
+  }
+  lua_setmetatable(L, 2);
+  return 1;
+}
+
+
+static const luaL_Reg base_funcs[] = {
+  {"assert", luaB_assert},
+  {"collectgarbage", luaB_collectgarbage},
+  {"dofile", luaB_dofile},
+  {"error", luaB_error},
+  {"gcinfo", luaB_gcinfo},
+  {"getfenv", luaB_getfenv},
+  {"getmetatable", luaB_getmetatable},
+  {"loadfile", luaB_loadfile},
+  {"load", luaB_load},
+  {"loadstring", luaB_loadstring},
+  {"next", luaB_next},
+  {"pcall", luaB_pcall},
+  {"print", luaB_print},
+  {"rawequal", luaB_rawequal},
+  {"rawget", luaB_rawget},
+  {"rawset", luaB_rawset},
+  {"select", luaB_select},
+  {"setfenv", luaB_setfenv},
+  {"setmetatable", luaB_setmetatable},
+  {"tonumber", luaB_tonumber},
+  {"tostring", luaB_tostring},
+  {"type", luaB_type},
+  {"unpack", luaB_unpack},
+  {"xpcall", luaB_xpcall},
+  {NULL, NULL}
+};
+
+
+/*
+** {======================================================
+** Coroutine library
+** =======================================================
+*/
+
+#define CO_RUN	0	/* running */
+#define CO_SUS	1	/* suspended */
+#define CO_NOR	2	/* 'normal' (it resumed another coroutine) */
+#define CO_DEAD	3
+
+static const char *const statnames[] =
+    {"running", "suspended", "normal", "dead"};
+
+static int costatus (lua_State *L, lua_State *co) {
+  if (L == co) return CO_RUN;
+  switch (lua_status(co)) {
+    case LUA_YIELD:
+      return CO_SUS;
+    case 0: {
+      lua_Debug ar;
+      if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */
+        return CO_NOR;  /* it is running */
+      else if (lua_gettop(co) == 0)
+          return CO_DEAD;
+      else
+        return CO_SUS;  /* initial state */
+    }
+    default:  /* some error occured */
+      return CO_DEAD;
+  }
+}
+
+
+static int luaB_costatus (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  lua_pushstring(L, statnames[costatus(L, co)]);
+  return 1;
+}
+
+
+static int auxresume (lua_State *L, lua_State *co, int narg) {
+  int status = costatus(L, co);
+  if (!lua_checkstack(co, narg))
+    luaL_error(L, "too many arguments to resume");
+  if (status != CO_SUS) {
+    lua_pushfstring(L, "cannot resume %s coroutine", statnames[status]);
+    return -1;  /* error flag */
+  }
+  lua_xmove(L, co, narg);
+  lua_setlevel(L, co);
+  status = lua_resume(co, narg);
+  if (status == 0 || status == LUA_YIELD) {
+    int nres = lua_gettop(co);
+    if (!lua_checkstack(L, nres + 1))
+      luaL_error(L, "too many results to resume");
+    lua_xmove(co, L, nres);  /* move yielded values */
+    return nres;
+  }
+  else {
+    lua_xmove(co, L, 1);  /* move error message */
+    return -1;  /* error flag */
+  }
+}
+
+
+static int luaB_coresume (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  int r;
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  r = auxresume(L, co, lua_gettop(L) - 1);
+  if (r < 0) {
+    lua_pushboolean(L, 0);
+    lua_insert(L, -2);
+    return 2;  /* return false + error message */
+  }
+  else {
+    lua_pushboolean(L, 1);
+    lua_insert(L, -(r + 1));
+    return r + 1;  /* return true + `resume' returns */
+  }
+}
+
+
+static int luaB_auxwrap (lua_State *L) {
+  lua_State *co = lua_tothread(L, lua_upvalueindex(1));
+  int r = auxresume(L, co, lua_gettop(L));
+  if (r < 0) {
+    if (lua_isstring(L, -1)) {  /* error object is a string? */
+      luaL_where(L, 1);  /* add extra info */
+      lua_insert(L, -2);
+      lua_concat(L, 2);
+    }
+    lua_error(L);  /* propagate error */
+  }
+  return r;
+}
+
+
+static int luaB_cocreate (lua_State *L) {
+  lua_State *NL = lua_newthread(L);
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,
+    "Lua function expected");
+  lua_pushvalue(L, 1);  /* move function to top */
+  lua_xmove(L, NL, 1);  /* move function from L to NL */
+  return 1;
+}
+
+
+static int luaB_cowrap (lua_State *L) {
+  luaB_cocreate(L);
+  lua_pushcclosure(L, luaB_auxwrap, 1);
+  return 1;
+}
+
+
+static int luaB_yield (lua_State *L) {
+  return lua_yield(L, lua_gettop(L));
+}
+
+
+static int luaB_corunning (lua_State *L) {
+  if (lua_pushthread(L))
+    lua_pushnil(L);  /* main thread is not a coroutine */
+  return 1;
+}
+
+
+static const luaL_Reg co_funcs[] = {
+  {"create", luaB_cocreate},
+  {"resume", luaB_coresume},
+  {"running", luaB_corunning},
+  {"status", luaB_costatus},
+  {"wrap", luaB_cowrap},
+  {"yield", luaB_yield},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+static void auxopen (lua_State *L, const char *name,
+                     lua_CFunction f, lua_CFunction u) {
+  lua_pushcfunction(L, u);
+  lua_pushcclosure(L, f, 1);
+  lua_setfield(L, -2, name);
+}
+
+
+static void base_open (lua_State *L) {
+  /* set global _G */
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  lua_setglobal(L, "_G");
+  /* open lib into global table */
+  luaL_register(L, "_G", base_funcs);
+  lua_pushliteral(L, LUA_VERSION);
+  lua_setglobal(L, "_VERSION");  /* set global _VERSION */
+  /* `ipairs' and `pairs' need auxiliary functions as upvalues */
+  auxopen(L, "ipairs", luaB_ipairs, ipairsaux);
+  auxopen(L, "pairs", luaB_pairs, luaB_next);
+  /* `newproxy' needs a weaktable as upvalue */
+  lua_createtable(L, 0, 1);  /* new table `w' */
+  lua_pushvalue(L, -1);  /* `w' will be its own metatable */
+  lua_setmetatable(L, -2);
+  lua_pushliteral(L, "kv");
+  lua_setfield(L, -2, "__mode");  /* metatable(w).__mode = "kv" */
+  lua_pushcclosure(L, luaB_newproxy, 1);
+  lua_setglobal(L, "newproxy");  /* set global `newproxy' */
+}
+
+
+LUALIB_API int luaopen_base (lua_State *L) {
+  base_open(L);
+  luaL_register(L, LUA_COLIBNAME, co_funcs);
+  return 2;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lcode.c b/third_party/lua-src/lua-5.1.5/lcode.c
new file mode 100644
index 00000000..679cb9cf
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lcode.c
@@ -0,0 +1,831 @@
+/*
+** $Id: lcode.c,v 2.25.1.5 2011/01/31 14:53:16 roberto Exp $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+
+#define lcode_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "ltable.h"
+
+
+#define hasjumps(e)	((e)->t != (e)->f)
+
+
+static int isnumeral(expdesc *e) {
+  return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP);
+}
+
+
+void luaK_nil (FuncState *fs, int from, int n) {
+  Instruction *previous;
+  if (fs->pc > fs->lasttarget) {  /* no jumps to current position? */
+    if (fs->pc == 0) {  /* function start? */
+      if (from >= fs->nactvar)
+        return;  /* positions are already clean */
+    }
+    else {
+      previous = &fs->f->code[fs->pc-1];
+      if (GET_OPCODE(*previous) == OP_LOADNIL) {
+        int pfrom = GETARG_A(*previous);
+        int pto = GETARG_B(*previous);
+        if (pfrom <= from && from <= pto+1) {  /* can connect both? */
+          if (from+n-1 > pto)
+            SETARG_B(*previous, from+n-1);
+          return;
+        }
+      }
+    }
+  }
+  luaK_codeABC(fs, OP_LOADNIL, from, from+n-1, 0);  /* else no optimization */
+}
+
+
+int luaK_jump (FuncState *fs) {
+  int jpc = fs->jpc;  /* save list of jumps to here */
+  int j;
+  fs->jpc = NO_JUMP;
+  j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP);
+  luaK_concat(fs, &j, jpc);  /* keep them on hold */
+  return j;
+}
+
+
+void luaK_ret (FuncState *fs, int first, int nret) {
+  luaK_codeABC(fs, OP_RETURN, first, nret+1, 0);
+}
+
+
+static int condjump (FuncState *fs, OpCode op, int A, int B, int C) {
+  luaK_codeABC(fs, op, A, B, C);
+  return luaK_jump(fs);
+}
+
+
+static void fixjump (FuncState *fs, int pc, int dest) {
+  Instruction *jmp = &fs->f->code[pc];
+  int offset = dest-(pc+1);
+  lua_assert(dest != NO_JUMP);
+  if (abs(offset) > MAXARG_sBx)
+    luaX_syntaxerror(fs->ls, "control structure too long");
+  SETARG_sBx(*jmp, offset);
+}
+
+
+/*
+** returns current `pc' and marks it as a jump target (to avoid wrong
+** optimizations with consecutive instructions not in the same basic block).
+*/
+int luaK_getlabel (FuncState *fs) {
+  fs->lasttarget = fs->pc;
+  return fs->pc;
+}
+
+
+static int getjump (FuncState *fs, int pc) {
+  int offset = GETARG_sBx(fs->f->code[pc]);
+  if (offset == NO_JUMP)  /* point to itself represents end of list */
+    return NO_JUMP;  /* end of list */
+  else
+    return (pc+1)+offset;  /* turn offset into absolute position */
+}
+
+
+static Instruction *getjumpcontrol (FuncState *fs, int pc) {
+  Instruction *pi = &fs->f->code[pc];
+  if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1))))
+    return pi-1;
+  else
+    return pi;
+}
+
+
+/*
+** check whether list has any jump that do not produce a value
+** (or produce an inverted value)
+*/
+static int need_value (FuncState *fs, int list) {
+  for (; list != NO_JUMP; list = getjump(fs, list)) {
+    Instruction i = *getjumpcontrol(fs, list);
+    if (GET_OPCODE(i) != OP_TESTSET) return 1;
+  }
+  return 0;  /* not found */
+}
+
+
+static int patchtestreg (FuncState *fs, int node, int reg) {
+  Instruction *i = getjumpcontrol(fs, node);
+  if (GET_OPCODE(*i) != OP_TESTSET)
+    return 0;  /* cannot patch other instructions */
+  if (reg != NO_REG && reg != GETARG_B(*i))
+    SETARG_A(*i, reg);
+  else  /* no register to put value or register already has the value */
+    *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i));
+
+  return 1;
+}
+
+
+static void removevalues (FuncState *fs, int list) {
+  for (; list != NO_JUMP; list = getjump(fs, list))
+      patchtestreg(fs, list, NO_REG);
+}
+
+
+static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
+                          int dtarget) {
+  while (list != NO_JUMP) {
+    int next = getjump(fs, list);
+    if (patchtestreg(fs, list, reg))
+      fixjump(fs, list, vtarget);
+    else
+      fixjump(fs, list, dtarget);  /* jump to default target */
+    list = next;
+  }
+}
+
+
+static void dischargejpc (FuncState *fs) {
+  patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc);
+  fs->jpc = NO_JUMP;
+}
+
+
+void luaK_patchlist (FuncState *fs, int list, int target) {
+  if (target == fs->pc)
+    luaK_patchtohere(fs, list);
+  else {
+    lua_assert(target < fs->pc);
+    patchlistaux(fs, list, target, NO_REG, target);
+  }
+}
+
+
+void luaK_patchtohere (FuncState *fs, int list) {
+  luaK_getlabel(fs);
+  luaK_concat(fs, &fs->jpc, list);
+}
+
+
+void luaK_concat (FuncState *fs, int *l1, int l2) {
+  if (l2 == NO_JUMP) return;
+  else if (*l1 == NO_JUMP)
+    *l1 = l2;
+  else {
+    int list = *l1;
+    int next;
+    while ((next = getjump(fs, list)) != NO_JUMP)  /* find last element */
+      list = next;
+    fixjump(fs, list, l2);
+  }
+}
+
+
+void luaK_checkstack (FuncState *fs, int n) {
+  int newstack = fs->freereg + n;
+  if (newstack > fs->f->maxstacksize) {
+    if (newstack >= MAXSTACK)
+      luaX_syntaxerror(fs->ls, "function or expression too complex");
+    fs->f->maxstacksize = cast_byte(newstack);
+  }
+}
+
+
+void luaK_reserveregs (FuncState *fs, int n) {
+  luaK_checkstack(fs, n);
+  fs->freereg += n;
+}
+
+
+static void freereg (FuncState *fs, int reg) {
+  if (!ISK(reg) && reg >= fs->nactvar) {
+    fs->freereg--;
+    lua_assert(reg == fs->freereg);
+  }
+}
+
+
+static void freeexp (FuncState *fs, expdesc *e) {
+  if (e->k == VNONRELOC)
+    freereg(fs, e->u.s.info);
+}
+
+
+static int addk (FuncState *fs, TValue *k, TValue *v) {
+  lua_State *L = fs->L;
+  TValue *idx = luaH_set(L, fs->h, k);
+  Proto *f = fs->f;
+  int oldsize = f->sizek;
+  if (ttisnumber(idx)) {
+    lua_assert(luaO_rawequalObj(&fs->f->k[cast_int(nvalue(idx))], v));
+    return cast_int(nvalue(idx));
+  }
+  else {  /* constant not found; create a new entry */
+    setnvalue(idx, cast_num(fs->nk));
+    luaM_growvector(L, f->k, fs->nk, f->sizek, TValue,
+                    MAXARG_Bx, "constant table overflow");
+    while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
+    setobj(L, &f->k[fs->nk], v);
+    luaC_barrier(L, f, v);
+    return fs->nk++;
+  }
+}
+
+
+int luaK_stringK (FuncState *fs, TString *s) {
+  TValue o;
+  setsvalue(fs->L, &o, s);
+  return addk(fs, &o, &o);
+}
+
+
+int luaK_numberK (FuncState *fs, lua_Number r) {
+  TValue o;
+  setnvalue(&o, r);
+  return addk(fs, &o, &o);
+}
+
+
+static int boolK (FuncState *fs, int b) {
+  TValue o;
+  setbvalue(&o, b);
+  return addk(fs, &o, &o);
+}
+
+
+static int nilK (FuncState *fs) {
+  TValue k, v;
+  setnilvalue(&v);
+  /* cannot use nil as key; instead use table itself to represent nil */
+  sethvalue(fs->L, &k, fs->h);
+  return addk(fs, &k, &v);
+}
+
+
+void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
+  if (e->k == VCALL) {  /* expression is an open function call? */
+    SETARG_C(getcode(fs, e), nresults+1);
+  }
+  else if (e->k == VVARARG) {
+    SETARG_B(getcode(fs, e), nresults+1);
+    SETARG_A(getcode(fs, e), fs->freereg);
+    luaK_reserveregs(fs, 1);
+  }
+}
+
+
+void luaK_setoneret (FuncState *fs, expdesc *e) {
+  if (e->k == VCALL) {  /* expression is an open function call? */
+    e->k = VNONRELOC;
+    e->u.s.info = GETARG_A(getcode(fs, e));
+  }
+  else if (e->k == VVARARG) {
+    SETARG_B(getcode(fs, e), 2);
+    e->k = VRELOCABLE;  /* can relocate its simple result */
+  }
+}
+
+
+void luaK_dischargevars (FuncState *fs, expdesc *e) {
+  switch (e->k) {
+    case VLOCAL: {
+      e->k = VNONRELOC;
+      break;
+    }
+    case VUPVAL: {
+      e->u.s.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.s.info, 0);
+      e->k = VRELOCABLE;
+      break;
+    }
+    case VGLOBAL: {
+      e->u.s.info = luaK_codeABx(fs, OP_GETGLOBAL, 0, e->u.s.info);
+      e->k = VRELOCABLE;
+      break;
+    }
+    case VINDEXED: {
+      freereg(fs, e->u.s.aux);
+      freereg(fs, e->u.s.info);
+      e->u.s.info = luaK_codeABC(fs, OP_GETTABLE, 0, e->u.s.info, e->u.s.aux);
+      e->k = VRELOCABLE;
+      break;
+    }
+    case VVARARG:
+    case VCALL: {
+      luaK_setoneret(fs, e);
+      break;
+    }
+    default: break;  /* there is one value available (somewhere) */
+  }
+}
+
+
+static int code_label (FuncState *fs, int A, int b, int jump) {
+  luaK_getlabel(fs);  /* those instructions may be jump targets */
+  return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump);
+}
+
+
+static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: {
+      luaK_nil(fs, reg, 1);
+      break;
+    }
+    case VFALSE:  case VTRUE: {
+      luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
+      break;
+    }
+    case VK: {
+      luaK_codeABx(fs, OP_LOADK, reg, e->u.s.info);
+      break;
+    }
+    case VKNUM: {
+      luaK_codeABx(fs, OP_LOADK, reg, luaK_numberK(fs, e->u.nval));
+      break;
+    }
+    case VRELOCABLE: {
+      Instruction *pc = &getcode(fs, e);
+      SETARG_A(*pc, reg);
+      break;
+    }
+    case VNONRELOC: {
+      if (reg != e->u.s.info)
+        luaK_codeABC(fs, OP_MOVE, reg, e->u.s.info, 0);
+      break;
+    }
+    default: {
+      lua_assert(e->k == VVOID || e->k == VJMP);
+      return;  /* nothing to do... */
+    }
+  }
+  e->u.s.info = reg;
+  e->k = VNONRELOC;
+}
+
+
+static void discharge2anyreg (FuncState *fs, expdesc *e) {
+  if (e->k != VNONRELOC) {
+    luaK_reserveregs(fs, 1);
+    discharge2reg(fs, e, fs->freereg-1);
+  }
+}
+
+
+static void exp2reg (FuncState *fs, expdesc *e, int reg) {
+  discharge2reg(fs, e, reg);
+  if (e->k == VJMP)
+    luaK_concat(fs, &e->t, e->u.s.info);  /* put this jump in `t' list */
+  if (hasjumps(e)) {
+    int final;  /* position after whole expression */
+    int p_f = NO_JUMP;  /* position of an eventual LOAD false */
+    int p_t = NO_JUMP;  /* position of an eventual LOAD true */
+    if (need_value(fs, e->t) || need_value(fs, e->f)) {
+      int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs);
+      p_f = code_label(fs, reg, 0, 1);
+      p_t = code_label(fs, reg, 1, 0);
+      luaK_patchtohere(fs, fj);
+    }
+    final = luaK_getlabel(fs);
+    patchlistaux(fs, e->f, final, reg, p_f);
+    patchlistaux(fs, e->t, final, reg, p_t);
+  }
+  e->f = e->t = NO_JUMP;
+  e->u.s.info = reg;
+  e->k = VNONRELOC;
+}
+
+
+void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  freeexp(fs, e);
+  luaK_reserveregs(fs, 1);
+  exp2reg(fs, e, fs->freereg - 1);
+}
+
+
+int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  if (e->k == VNONRELOC) {
+    if (!hasjumps(e)) return e->u.s.info;  /* exp is already in a register */
+    if (e->u.s.info >= fs->nactvar) {  /* reg. is not a local? */
+      exp2reg(fs, e, e->u.s.info);  /* put value on it */
+      return e->u.s.info;
+    }
+  }
+  luaK_exp2nextreg(fs, e);  /* default */
+  return e->u.s.info;
+}
+
+
+void luaK_exp2val (FuncState *fs, expdesc *e) {
+  if (hasjumps(e))
+    luaK_exp2anyreg(fs, e);
+  else
+    luaK_dischargevars(fs, e);
+}
+
+
+int luaK_exp2RK (FuncState *fs, expdesc *e) {
+  luaK_exp2val(fs, e);
+  switch (e->k) {
+    case VKNUM:
+    case VTRUE:
+    case VFALSE:
+    case VNIL: {
+      if (fs->nk <= MAXINDEXRK) {  /* constant fit in RK operand? */
+        e->u.s.info = (e->k == VNIL)  ? nilK(fs) :
+                      (e->k == VKNUM) ? luaK_numberK(fs, e->u.nval) :
+                                        boolK(fs, (e->k == VTRUE));
+        e->k = VK;
+        return RKASK(e->u.s.info);
+      }
+      else break;
+    }
+    case VK: {
+      if (e->u.s.info <= MAXINDEXRK)  /* constant fit in argC? */
+        return RKASK(e->u.s.info);
+      else break;
+    }
+    default: break;
+  }
+  /* not a constant in the right range: put it in a register */
+  return luaK_exp2anyreg(fs, e);
+}
+
+
+void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
+  switch (var->k) {
+    case VLOCAL: {
+      freeexp(fs, ex);
+      exp2reg(fs, ex, var->u.s.info);
+      return;
+    }
+    case VUPVAL: {
+      int e = luaK_exp2anyreg(fs, ex);
+      luaK_codeABC(fs, OP_SETUPVAL, e, var->u.s.info, 0);
+      break;
+    }
+    case VGLOBAL: {
+      int e = luaK_exp2anyreg(fs, ex);
+      luaK_codeABx(fs, OP_SETGLOBAL, e, var->u.s.info);
+      break;
+    }
+    case VINDEXED: {
+      int e = luaK_exp2RK(fs, ex);
+      luaK_codeABC(fs, OP_SETTABLE, var->u.s.info, var->u.s.aux, e);
+      break;
+    }
+    default: {
+      lua_assert(0);  /* invalid var kind to store */
+      break;
+    }
+  }
+  freeexp(fs, ex);
+}
+
+
+void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
+  int func;
+  luaK_exp2anyreg(fs, e);
+  freeexp(fs, e);
+  func = fs->freereg;
+  luaK_reserveregs(fs, 2);
+  luaK_codeABC(fs, OP_SELF, func, e->u.s.info, luaK_exp2RK(fs, key));
+  freeexp(fs, key);
+  e->u.s.info = func;
+  e->k = VNONRELOC;
+}
+
+
+static void invertjump (FuncState *fs, expdesc *e) {
+  Instruction *pc = getjumpcontrol(fs, e->u.s.info);
+  lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
+                                           GET_OPCODE(*pc) != OP_TEST);
+  SETARG_A(*pc, !(GETARG_A(*pc)));
+}
+
+
+static int jumponcond (FuncState *fs, expdesc *e, int cond) {
+  if (e->k == VRELOCABLE) {
+    Instruction ie = getcode(fs, e);
+    if (GET_OPCODE(ie) == OP_NOT) {
+      fs->pc--;  /* remove previous OP_NOT */
+      return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond);
+    }
+    /* else go through */
+  }
+  discharge2anyreg(fs, e);
+  freeexp(fs, e);
+  return condjump(fs, OP_TESTSET, NO_REG, e->u.s.info, cond);
+}
+
+
+void luaK_goiftrue (FuncState *fs, expdesc *e) {
+  int pc;  /* pc of last jump */
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VK: case VKNUM: case VTRUE: {
+      pc = NO_JUMP;  /* always true; do nothing */
+      break;
+    }
+    case VJMP: {
+      invertjump(fs, e);
+      pc = e->u.s.info;
+      break;
+    }
+    default: {
+      pc = jumponcond(fs, e, 0);
+      break;
+    }
+  }
+  luaK_concat(fs, &e->f, pc);  /* insert last jump in `f' list */
+  luaK_patchtohere(fs, e->t);
+  e->t = NO_JUMP;
+}
+
+
+static void luaK_goiffalse (FuncState *fs, expdesc *e) {
+  int pc;  /* pc of last jump */
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: case VFALSE: {
+      pc = NO_JUMP;  /* always false; do nothing */
+      break;
+    }
+    case VJMP: {
+      pc = e->u.s.info;
+      break;
+    }
+    default: {
+      pc = jumponcond(fs, e, 1);
+      break;
+    }
+  }
+  luaK_concat(fs, &e->t, pc);  /* insert last jump in `t' list */
+  luaK_patchtohere(fs, e->f);
+  e->f = NO_JUMP;
+}
+
+
+static void codenot (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: case VFALSE: {
+      e->k = VTRUE;
+      break;
+    }
+    case VK: case VKNUM: case VTRUE: {
+      e->k = VFALSE;
+      break;
+    }
+    case VJMP: {
+      invertjump(fs, e);
+      break;
+    }
+    case VRELOCABLE:
+    case VNONRELOC: {
+      discharge2anyreg(fs, e);
+      freeexp(fs, e);
+      e->u.s.info = luaK_codeABC(fs, OP_NOT, 0, e->u.s.info, 0);
+      e->k = VRELOCABLE;
+      break;
+    }
+    default: {
+      lua_assert(0);  /* cannot happen */
+      break;
+    }
+  }
+  /* interchange true and false lists */
+  { int temp = e->f; e->f = e->t; e->t = temp; }
+  removevalues(fs, e->f);
+  removevalues(fs, e->t);
+}
+
+
+void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
+  t->u.s.aux = luaK_exp2RK(fs, k);
+  t->k = VINDEXED;
+}
+
+
+static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
+  lua_Number v1, v2, r;
+  if (!isnumeral(e1) || !isnumeral(e2)) return 0;
+  v1 = e1->u.nval;
+  v2 = e2->u.nval;
+  switch (op) {
+    case OP_ADD: r = luai_numadd(v1, v2); break;
+    case OP_SUB: r = luai_numsub(v1, v2); break;
+    case OP_MUL: r = luai_nummul(v1, v2); break;
+    case OP_DIV:
+      if (v2 == 0) return 0;  /* do not attempt to divide by 0 */
+      r = luai_numdiv(v1, v2); break;
+    case OP_MOD:
+      if (v2 == 0) return 0;  /* do not attempt to divide by 0 */
+      r = luai_nummod(v1, v2); break;
+    case OP_POW: r = luai_numpow(v1, v2); break;
+    case OP_UNM: r = luai_numunm(v1); break;
+    case OP_LEN: return 0;  /* no constant folding for 'len' */
+    default: lua_assert(0); r = 0; break;
+  }
+  if (luai_numisnan(r)) return 0;  /* do not attempt to produce NaN */
+  e1->u.nval = r;
+  return 1;
+}
+
+
+static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
+  if (constfolding(op, e1, e2))
+    return;
+  else {
+    int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0;
+    int o1 = luaK_exp2RK(fs, e1);
+    if (o1 > o2) {
+      freeexp(fs, e1);
+      freeexp(fs, e2);
+    }
+    else {
+      freeexp(fs, e2);
+      freeexp(fs, e1);
+    }
+    e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2);
+    e1->k = VRELOCABLE;
+  }
+}
+
+
+static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
+                                                          expdesc *e2) {
+  int o1 = luaK_exp2RK(fs, e1);
+  int o2 = luaK_exp2RK(fs, e2);
+  freeexp(fs, e2);
+  freeexp(fs, e1);
+  if (cond == 0 && op != OP_EQ) {
+    int temp;  /* exchange args to replace by `<' or `<=' */
+    temp = o1; o1 = o2; o2 = temp;  /* o1 <==> o2 */
+    cond = 1;
+  }
+  e1->u.s.info = condjump(fs, op, cond, o1, o2);
+  e1->k = VJMP;
+}
+
+
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
+  expdesc e2;
+  e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
+  switch (op) {
+    case OPR_MINUS: {
+      if (!isnumeral(e))
+        luaK_exp2anyreg(fs, e);  /* cannot operate on non-numeric constants */
+      codearith(fs, OP_UNM, e, &e2);
+      break;
+    }
+    case OPR_NOT: codenot(fs, e); break;
+    case OPR_LEN: {
+      luaK_exp2anyreg(fs, e);  /* cannot operate on constants */
+      codearith(fs, OP_LEN, e, &e2);
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
+  switch (op) {
+    case OPR_AND: {
+      luaK_goiftrue(fs, v);
+      break;
+    }
+    case OPR_OR: {
+      luaK_goiffalse(fs, v);
+      break;
+    }
+    case OPR_CONCAT: {
+      luaK_exp2nextreg(fs, v);  /* operand must be on the `stack' */
+      break;
+    }
+    case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
+    case OPR_MOD: case OPR_POW: {
+      if (!isnumeral(v)) luaK_exp2RK(fs, v);
+      break;
+    }
+    default: {
+      luaK_exp2RK(fs, v);
+      break;
+    }
+  }
+}
+
+
+void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
+  switch (op) {
+    case OPR_AND: {
+      lua_assert(e1->t == NO_JUMP);  /* list must be closed */
+      luaK_dischargevars(fs, e2);
+      luaK_concat(fs, &e2->f, e1->f);
+      *e1 = *e2;
+      break;
+    }
+    case OPR_OR: {
+      lua_assert(e1->f == NO_JUMP);  /* list must be closed */
+      luaK_dischargevars(fs, e2);
+      luaK_concat(fs, &e2->t, e1->t);
+      *e1 = *e2;
+      break;
+    }
+    case OPR_CONCAT: {
+      luaK_exp2val(fs, e2);
+      if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) {
+        lua_assert(e1->u.s.info == GETARG_B(getcode(fs, e2))-1);
+        freeexp(fs, e1);
+        SETARG_B(getcode(fs, e2), e1->u.s.info);
+        e1->k = VRELOCABLE; e1->u.s.info = e2->u.s.info;
+      }
+      else {
+        luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
+        codearith(fs, OP_CONCAT, e1, e2);
+      }
+      break;
+    }
+    case OPR_ADD: codearith(fs, OP_ADD, e1, e2); break;
+    case OPR_SUB: codearith(fs, OP_SUB, e1, e2); break;
+    case OPR_MUL: codearith(fs, OP_MUL, e1, e2); break;
+    case OPR_DIV: codearith(fs, OP_DIV, e1, e2); break;
+    case OPR_MOD: codearith(fs, OP_MOD, e1, e2); break;
+    case OPR_POW: codearith(fs, OP_POW, e1, e2); break;
+    case OPR_EQ: codecomp(fs, OP_EQ, 1, e1, e2); break;
+    case OPR_NE: codecomp(fs, OP_EQ, 0, e1, e2); break;
+    case OPR_LT: codecomp(fs, OP_LT, 1, e1, e2); break;
+    case OPR_LE: codecomp(fs, OP_LE, 1, e1, e2); break;
+    case OPR_GT: codecomp(fs, OP_LT, 0, e1, e2); break;
+    case OPR_GE: codecomp(fs, OP_LE, 0, e1, e2); break;
+    default: lua_assert(0);
+  }
+}
+
+
+void luaK_fixline (FuncState *fs, int line) {
+  fs->f->lineinfo[fs->pc - 1] = line;
+}
+
+
+static int luaK_code (FuncState *fs, Instruction i, int line) {
+  Proto *f = fs->f;
+  dischargejpc(fs);  /* `pc' will change */
+  /* put new instruction in code array */
+  luaM_growvector(fs->L, f->code, fs->pc, f->sizecode, Instruction,
+                  MAX_INT, "code size overflow");
+  f->code[fs->pc] = i;
+  /* save corresponding line information */
+  luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
+                  MAX_INT, "code size overflow");
+  f->lineinfo[fs->pc] = line;
+  return fs->pc++;
+}
+
+
+int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) {
+  lua_assert(getOpMode(o) == iABC);
+  lua_assert(getBMode(o) != OpArgN || b == 0);
+  lua_assert(getCMode(o) != OpArgN || c == 0);
+  return luaK_code(fs, CREATE_ABC(o, a, b, c), fs->ls->lastline);
+}
+
+
+int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
+  lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx);
+  lua_assert(getCMode(o) == OpArgN);
+  return luaK_code(fs, CREATE_ABx(o, a, bc), fs->ls->lastline);
+}
+
+
+void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
+  int c =  (nelems - 1)/LFIELDS_PER_FLUSH + 1;
+  int b = (tostore == LUA_MULTRET) ? 0 : tostore;
+  lua_assert(tostore != 0);
+  if (c <= MAXARG_C)
+    luaK_codeABC(fs, OP_SETLIST, base, b, c);
+  else {
+    luaK_codeABC(fs, OP_SETLIST, base, b, 0);
+    luaK_code(fs, cast(Instruction, c), fs->ls->lastline);
+  }
+  fs->freereg = base + 1;  /* free registers with list values */
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lcode.h b/third_party/lua-src/lua-5.1.5/lcode.h
new file mode 100644
index 00000000..b941c607
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lcode.h
@@ -0,0 +1,76 @@
+/*
+** $Id: lcode.h,v 1.48.1.1 2007/12/27 13:02:25 roberto Exp $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lcode_h
+#define lcode_h
+
+#include "llex.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+
+
+/*
+** Marks the end of a patch list. It is an invalid value both as an absolute
+** address, and as a list link (would link an element to itself).
+*/
+#define NO_JUMP (-1)
+
+
+/*
+** grep "ORDER OPR" if you change these enums
+*/
+typedef enum BinOpr {
+  OPR_ADD, OPR_SUB, OPR_MUL, OPR_DIV, OPR_MOD, OPR_POW,
+  OPR_CONCAT,
+  OPR_NE, OPR_EQ,
+  OPR_LT, OPR_LE, OPR_GT, OPR_GE,
+  OPR_AND, OPR_OR,
+  OPR_NOBINOPR
+} BinOpr;
+
+
+typedef enum UnOpr { OPR_MINUS, OPR_NOT, OPR_LEN, OPR_NOUNOPR } UnOpr;
+
+
+#define getcode(fs,e)	((fs)->f->code[(e)->u.s.info])
+
+#define luaK_codeAsBx(fs,o,A,sBx)	luaK_codeABx(fs,o,A,(sBx)+MAXARG_sBx)
+
+#define luaK_setmultret(fs,e)	luaK_setreturns(fs, e, LUA_MULTRET)
+
+LUAI_FUNC int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned int Bx);
+LUAI_FUNC int luaK_codeABC (FuncState *fs, OpCode o, int A, int B, int C);
+LUAI_FUNC void luaK_fixline (FuncState *fs, int line);
+LUAI_FUNC void luaK_nil (FuncState *fs, int from, int n);
+LUAI_FUNC void luaK_reserveregs (FuncState *fs, int n);
+LUAI_FUNC void luaK_checkstack (FuncState *fs, int n);
+LUAI_FUNC int luaK_stringK (FuncState *fs, TString *s);
+LUAI_FUNC int luaK_numberK (FuncState *fs, lua_Number r);
+LUAI_FUNC void luaK_dischargevars (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_exp2anyreg (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2nextreg (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2val (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_exp2RK (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_self (FuncState *fs, expdesc *e, expdesc *key);
+LUAI_FUNC void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k);
+LUAI_FUNC void luaK_goiftrue (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_storevar (FuncState *fs, expdesc *var, expdesc *e);
+LUAI_FUNC void luaK_setreturns (FuncState *fs, expdesc *e, int nresults);
+LUAI_FUNC void luaK_setoneret (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_jump (FuncState *fs);
+LUAI_FUNC void luaK_ret (FuncState *fs, int first, int nret);
+LUAI_FUNC void luaK_patchlist (FuncState *fs, int list, int target);
+LUAI_FUNC void luaK_patchtohere (FuncState *fs, int list);
+LUAI_FUNC void luaK_concat (FuncState *fs, int *l1, int l2);
+LUAI_FUNC int luaK_getlabel (FuncState *fs);
+LUAI_FUNC void luaK_prefix (FuncState *fs, UnOpr op, expdesc *v);
+LUAI_FUNC void luaK_infix (FuncState *fs, BinOpr op, expdesc *v);
+LUAI_FUNC void luaK_posfix (FuncState *fs, BinOpr op, expdesc *v1, expdesc *v2);
+LUAI_FUNC void luaK_setlist (FuncState *fs, int base, int nelems, int tostore);
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/ldblib.c b/third_party/lua-src/lua-5.1.5/ldblib.c
new file mode 100644
index 00000000..2027eda5
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ldblib.c
@@ -0,0 +1,398 @@
+/*
+** $Id: ldblib.c,v 1.104.1.4 2009/08/04 18:50:18 roberto Exp $
+** Interface from Lua to its debug API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldblib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+static int db_getregistry (lua_State *L) {
+  lua_pushvalue(L, LUA_REGISTRYINDEX);
+  return 1;
+}
+
+
+static int db_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);  /* no metatable */
+  }
+  return 1;
+}
+
+
+static int db_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
+                    "nil or table expected");
+  lua_settop(L, 2);
+  lua_pushboolean(L, lua_setmetatable(L, 1));
+  return 1;
+}
+
+
+static int db_getfenv (lua_State *L) {
+  luaL_checkany(L, 1);
+  lua_getfenv(L, 1);
+  return 1;
+}
+
+
+static int db_setfenv (lua_State *L) {
+  luaL_checktype(L, 2, LUA_TTABLE);
+  lua_settop(L, 2);
+  if (lua_setfenv(L, 1) == 0)
+    luaL_error(L, LUA_QL("setfenv")
+                  " cannot change environment of given object");
+  return 1;
+}
+
+
+static void settabss (lua_State *L, const char *i, const char *v) {
+  lua_pushstring(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
+static void settabsi (lua_State *L, const char *i, int v) {
+  lua_pushinteger(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
+static lua_State *getthread (lua_State *L, int *arg) {
+  if (lua_isthread(L, 1)) {
+    *arg = 1;
+    return lua_tothread(L, 1);
+  }
+  else {
+    *arg = 0;
+    return L;
+  }
+}
+
+
+static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
+  if (L == L1) {
+    lua_pushvalue(L, -2);
+    lua_remove(L, -3);
+  }
+  else
+    lua_xmove(L1, L, 1);
+  lua_setfield(L, -2, fname);
+}
+
+
+static int db_getinfo (lua_State *L) {
+  lua_Debug ar;
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  const char *options = luaL_optstring(L, arg+2, "flnSu");
+  if (lua_isnumber(L, arg+1)) {
+    if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
+      lua_pushnil(L);  /* level out of range */
+      return 1;
+    }
+  }
+  else if (lua_isfunction(L, arg+1)) {
+    lua_pushfstring(L, ">%s", options);
+    options = lua_tostring(L, -1);
+    lua_pushvalue(L, arg+1);
+    lua_xmove(L, L1, 1);
+  }
+  else
+    return luaL_argerror(L, arg+1, "function or level expected");
+  if (!lua_getinfo(L1, options, &ar))
+    return luaL_argerror(L, arg+2, "invalid option");
+  lua_createtable(L, 0, 2);
+  if (strchr(options, 'S')) {
+    settabss(L, "source", ar.source);
+    settabss(L, "short_src", ar.short_src);
+    settabsi(L, "linedefined", ar.linedefined);
+    settabsi(L, "lastlinedefined", ar.lastlinedefined);
+    settabss(L, "what", ar.what);
+  }
+  if (strchr(options, 'l'))
+    settabsi(L, "currentline", ar.currentline);
+  if (strchr(options, 'u'))
+    settabsi(L, "nups", ar.nups);
+  if (strchr(options, 'n')) {
+    settabss(L, "name", ar.name);
+    settabss(L, "namewhat", ar.namewhat);
+  }
+  if (strchr(options, 'L'))
+    treatstackoption(L, L1, "activelines");
+  if (strchr(options, 'f'))
+    treatstackoption(L, L1, "func");
+  return 1;  /* return table */
+}
+    
+
+static int db_getlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  const char *name;
+  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));
+  if (name) {
+    lua_xmove(L1, L, 1);
+    lua_pushstring(L, name);
+    lua_pushvalue(L, -2);
+    return 2;
+  }
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int db_setlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  luaL_checkany(L, arg+3);
+  lua_settop(L, arg+3);
+  lua_xmove(L, L1, 1);
+  lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
+  return 1;
+}
+
+
+static int auxupvalue (lua_State *L, int get) {
+  const char *name;
+  int n = luaL_checkint(L, 2);
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  if (lua_iscfunction(L, 1)) return 0;  /* cannot touch C upvalues from Lua */
+  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
+  if (name == NULL) return 0;
+  lua_pushstring(L, name);
+  lua_insert(L, -(get+1));
+  return get + 1;
+}
+
+
+static int db_getupvalue (lua_State *L) {
+  return auxupvalue(L, 1);
+}
+
+
+static int db_setupvalue (lua_State *L) {
+  luaL_checkany(L, 3);
+  return auxupvalue(L, 0);
+}
+
+
+
+static const char KEY_HOOK = 'h';
+
+
+static void hookf (lua_State *L, lua_Debug *ar) {
+  static const char *const hooknames[] =
+    {"call", "return", "line", "count", "tail return"};
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  lua_pushlightuserdata(L, L);
+  lua_rawget(L, -2);
+  if (lua_isfunction(L, -1)) {
+    lua_pushstring(L, hooknames[(int)ar->event]);
+    if (ar->currentline >= 0)
+      lua_pushinteger(L, ar->currentline);
+    else lua_pushnil(L);
+    lua_assert(lua_getinfo(L, "lS", ar));
+    lua_call(L, 2, 0);
+  }
+}
+
+
+static int makemask (const char *smask, int count) {
+  int mask = 0;
+  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+  if (count > 0) mask |= LUA_MASKCOUNT;
+  return mask;
+}
+
+
+static char *unmakemask (int mask, char *smask) {
+  int i = 0;
+  if (mask & LUA_MASKCALL) smask[i++] = 'c';
+  if (mask & LUA_MASKRET) smask[i++] = 'r';
+  if (mask & LUA_MASKLINE) smask[i++] = 'l';
+  smask[i] = '\0';
+  return smask;
+}
+
+
+static void gethooktable (lua_State *L) {
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  if (!lua_istable(L, -1)) {
+    lua_pop(L, 1);
+    lua_createtable(L, 0, 1);
+    lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+    lua_pushvalue(L, -2);
+    lua_rawset(L, LUA_REGISTRYINDEX);
+  }
+}
+
+
+static int db_sethook (lua_State *L) {
+  int arg, mask, count;
+  lua_Hook func;
+  lua_State *L1 = getthread(L, &arg);
+  if (lua_isnoneornil(L, arg+1)) {
+    lua_settop(L, arg+1);
+    func = NULL; mask = 0; count = 0;  /* turn off hooks */
+  }
+  else {
+    const char *smask = luaL_checkstring(L, arg+2);
+    luaL_checktype(L, arg+1, LUA_TFUNCTION);
+    count = luaL_optint(L, arg+3, 0);
+    func = hookf; mask = makemask(smask, count);
+  }
+  gethooktable(L);
+  lua_pushlightuserdata(L, L1);
+  lua_pushvalue(L, arg+1);
+  lua_rawset(L, -3);  /* set new hook */
+  lua_pop(L, 1);  /* remove hook table */
+  lua_sethook(L1, func, mask, count);  /* set hooks */
+  return 0;
+}
+
+
+static int db_gethook (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  char buff[5];
+  int mask = lua_gethookmask(L1);
+  lua_Hook hook = lua_gethook(L1);
+  if (hook != NULL && hook != hookf)  /* external hook? */
+    lua_pushliteral(L, "external hook");
+  else {
+    gethooktable(L);
+    lua_pushlightuserdata(L, L1);
+    lua_rawget(L, -2);   /* get hook */
+    lua_remove(L, -2);  /* remove hook table */
+  }
+  lua_pushstring(L, unmakemask(mask, buff));
+  lua_pushinteger(L, lua_gethookcount(L1));
+  return 3;
+}
+
+
+static int db_debug (lua_State *L) {
+  for (;;) {
+    char buffer[250];
+    fputs("lua_debug> ", stderr);
+    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
+        strcmp(buffer, "cont\n") == 0)
+      return 0;
+    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
+        lua_pcall(L, 0, 0, 0)) {
+      fputs(lua_tostring(L, -1), stderr);
+      fputs("\n", stderr);
+    }
+    lua_settop(L, 0);  /* remove eventual returns */
+  }
+}
+
+
+#define LEVELS1	12	/* size of the first part of the stack */
+#define LEVELS2	10	/* size of the second part of the stack */
+
+static int db_errorfb (lua_State *L) {
+  int level;
+  int firstpart = 1;  /* still before eventual `...' */
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  if (lua_isnumber(L, arg+2)) {
+    level = (int)lua_tointeger(L, arg+2);
+    lua_pop(L, 1);
+  }
+  else
+    level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
+  if (lua_gettop(L) == arg)
+    lua_pushliteral(L, "");
+  else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
+  else lua_pushliteral(L, "\n");
+  lua_pushliteral(L, "stack traceback:");
+  while (lua_getstack(L1, level++, &ar)) {
+    if (level > LEVELS1 && firstpart) {
+      /* no more than `LEVELS2' more levels? */
+      if (!lua_getstack(L1, level+LEVELS2, &ar))
+        level--;  /* keep going */
+      else {
+        lua_pushliteral(L, "\n\t...");  /* too many levels */
+        while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
+          level++;
+      }
+      firstpart = 0;
+      continue;
+    }
+    lua_pushliteral(L, "\n\t");
+    lua_getinfo(L1, "Snl", &ar);
+    lua_pushfstring(L, "%s:", ar.short_src);
+    if (ar.currentline > 0)
+      lua_pushfstring(L, "%d:", ar.currentline);
+    if (*ar.namewhat != '\0')  /* is there a name? */
+        lua_pushfstring(L, " in function " LUA_QS, ar.name);
+    else {
+      if (*ar.what == 'm')  /* main? */
+        lua_pushfstring(L, " in main chunk");
+      else if (*ar.what == 'C' || *ar.what == 't')
+        lua_pushliteral(L, " ?");  /* C function or tail call */
+      else
+        lua_pushfstring(L, " in function <%s:%d>",
+                           ar.short_src, ar.linedefined);
+    }
+    lua_concat(L, lua_gettop(L) - arg);
+  }
+  lua_concat(L, lua_gettop(L) - arg);
+  return 1;
+}
+
+
+static const luaL_Reg dblib[] = {
+  {"debug", db_debug},
+  {"getfenv", db_getfenv},
+  {"gethook", db_gethook},
+  {"getinfo", db_getinfo},
+  {"getlocal", db_getlocal},
+  {"getregistry", db_getregistry},
+  {"getmetatable", db_getmetatable},
+  {"getupvalue", db_getupvalue},
+  {"setfenv", db_setfenv},
+  {"sethook", db_sethook},
+  {"setlocal", db_setlocal},
+  {"setmetatable", db_setmetatable},
+  {"setupvalue", db_setupvalue},
+  {"traceback", db_errorfb},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_debug (lua_State *L) {
+  luaL_register(L, LUA_DBLIBNAME, dblib);
+  return 1;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/ldebug.c b/third_party/lua-src/lua-5.1.5/ldebug.c
new file mode 100644
index 00000000..50ad3d38
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ldebug.c
@@ -0,0 +1,638 @@
+/*
+** $Id: ldebug.c,v 2.29.1.6 2008/05/08 16:56:26 roberto Exp $
+** Debug Interface
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+
+
+#define ldebug_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name);
+
+
+static int currentpc (lua_State *L, CallInfo *ci) {
+  if (!isLua(ci)) return -1;  /* function is not a Lua function? */
+  if (ci == L->ci)
+    ci->savedpc = L->savedpc;
+  return pcRel(ci->savedpc, ci_func(ci)->l.p);
+}
+
+
+static int currentline (lua_State *L, CallInfo *ci) {
+  int pc = currentpc(L, ci);
+  if (pc < 0)
+    return -1;  /* only active lua functions have current-line information */
+  else
+    return getline(ci_func(ci)->l.p, pc);
+}
+
+
+/*
+** this function can be called asynchronous (e.g. during a signal)
+*/
+LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
+  if (func == NULL || mask == 0) {  /* turn off hooks? */
+    mask = 0;
+    func = NULL;
+  }
+  L->hook = func;
+  L->basehookcount = count;
+  resethookcount(L);
+  L->hookmask = cast_byte(mask);
+  return 1;
+}
+
+
+LUA_API lua_Hook lua_gethook (lua_State *L) {
+  return L->hook;
+}
+
+
+LUA_API int lua_gethookmask (lua_State *L) {
+  return L->hookmask;
+}
+
+
+LUA_API int lua_gethookcount (lua_State *L) {
+  return L->basehookcount;
+}
+
+
+LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
+  int status;
+  CallInfo *ci;
+  lua_lock(L);
+  for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
+    level--;
+    if (f_isLua(ci))  /* Lua function? */
+      level -= ci->tailcalls;  /* skip lost tail calls */
+  }
+  if (level == 0 && ci > L->base_ci) {  /* level found? */
+    status = 1;
+    ar->i_ci = cast_int(ci - L->base_ci);
+  }
+  else if (level < 0) {  /* level is of a lost tail call? */
+    status = 1;
+    ar->i_ci = 0;
+  }
+  else status = 0;  /* no such level */
+  lua_unlock(L);
+  return status;
+}
+
+
+static Proto *getluaproto (CallInfo *ci) {
+  return (isLua(ci) ? ci_func(ci)->l.p : NULL);
+}
+
+
+static const char *findlocal (lua_State *L, CallInfo *ci, int n) {
+  const char *name;
+  Proto *fp = getluaproto(ci);
+  if (fp && (name = luaF_getlocalname(fp, n, currentpc(L, ci))) != NULL)
+    return name;  /* is a local variable in a Lua function */
+  else {
+    StkId limit = (ci == L->ci) ? L->top : (ci+1)->func;
+    if (limit - ci->base >= n && n > 0)  /* is 'n' inside 'ci' stack? */
+      return "(*temporary)";
+    else
+      return NULL;
+  }
+}
+
+
+LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
+  CallInfo *ci = L->base_ci + ar->i_ci;
+  const char *name = findlocal(L, ci, n);
+  lua_lock(L);
+  if (name)
+      luaA_pushobject(L, ci->base + (n - 1));
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
+  CallInfo *ci = L->base_ci + ar->i_ci;
+  const char *name = findlocal(L, ci, n);
+  lua_lock(L);
+  if (name)
+      setobjs2s(L, ci->base + (n - 1), L->top - 1);
+  L->top--;  /* pop value */
+  lua_unlock(L);
+  return name;
+}
+
+
+static void funcinfo (lua_Debug *ar, Closure *cl) {
+  if (cl->c.isC) {
+    ar->source = "=[C]";
+    ar->linedefined = -1;
+    ar->lastlinedefined = -1;
+    ar->what = "C";
+  }
+  else {
+    ar->source = getstr(cl->l.p->source);
+    ar->linedefined = cl->l.p->linedefined;
+    ar->lastlinedefined = cl->l.p->lastlinedefined;
+    ar->what = (ar->linedefined == 0) ? "main" : "Lua";
+  }
+  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
+}
+
+
+static void info_tailcall (lua_Debug *ar) {
+  ar->name = ar->namewhat = "";
+  ar->what = "tail";
+  ar->lastlinedefined = ar->linedefined = ar->currentline = -1;
+  ar->source = "=(tail call)";
+  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
+  ar->nups = 0;
+}
+
+
+static void collectvalidlines (lua_State *L, Closure *f) {
+  if (f == NULL || f->c.isC) {
+    setnilvalue(L->top);
+  }
+  else {
+    Table *t = luaH_new(L, 0, 0);
+    int *lineinfo = f->l.p->lineinfo;
+    int i;
+    for (i=0; i<f->l.p->sizelineinfo; i++)
+      setbvalue(luaH_setnum(L, t, lineinfo[i]), 1);
+    sethvalue(L, L->top, t); 
+  }
+  incr_top(L);
+}
+
+
+static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
+                    Closure *f, CallInfo *ci) {
+  int status = 1;
+  if (f == NULL) {
+    info_tailcall(ar);
+    return status;
+  }
+  for (; *what; what++) {
+    switch (*what) {
+      case 'S': {
+        funcinfo(ar, f);
+        break;
+      }
+      case 'l': {
+        ar->currentline = (ci) ? currentline(L, ci) : -1;
+        break;
+      }
+      case 'u': {
+        ar->nups = f->c.nupvalues;
+        break;
+      }
+      case 'n': {
+        ar->namewhat = (ci) ? getfuncname(L, ci, &ar->name) : NULL;
+        if (ar->namewhat == NULL) {
+          ar->namewhat = "";  /* not found */
+          ar->name = NULL;
+        }
+        break;
+      }
+      case 'L':
+      case 'f':  /* handled by lua_getinfo */
+        break;
+      default: status = 0;  /* invalid option */
+    }
+  }
+  return status;
+}
+
+
+LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
+  int status;
+  Closure *f = NULL;
+  CallInfo *ci = NULL;
+  lua_lock(L);
+  if (*what == '>') {
+    StkId func = L->top - 1;
+    luai_apicheck(L, ttisfunction(func));
+    what++;  /* skip the '>' */
+    f = clvalue(func);
+    L->top--;  /* pop function */
+  }
+  else if (ar->i_ci != 0) {  /* no tail call? */
+    ci = L->base_ci + ar->i_ci;
+    lua_assert(ttisfunction(ci->func));
+    f = clvalue(ci->func);
+  }
+  status = auxgetinfo(L, what, ar, f, ci);
+  if (strchr(what, 'f')) {
+    if (f == NULL) setnilvalue(L->top);
+    else setclvalue(L, L->top, f);
+    incr_top(L);
+  }
+  if (strchr(what, 'L'))
+    collectvalidlines(L, f);
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** {======================================================
+** Symbolic Execution and code checker
+** =======================================================
+*/
+
+#define check(x)		if (!(x)) return 0;
+
+#define checkjump(pt,pc)	check(0 <= pc && pc < pt->sizecode)
+
+#define checkreg(pt,reg)	check((reg) < (pt)->maxstacksize)
+
+
+
+static int precheck (const Proto *pt) {
+  check(pt->maxstacksize <= MAXSTACK);
+  check(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize);
+  check(!(pt->is_vararg & VARARG_NEEDSARG) ||
+              (pt->is_vararg & VARARG_HASARG));
+  check(pt->sizeupvalues <= pt->nups);
+  check(pt->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0);
+  check(pt->sizecode > 0 && GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN);
+  return 1;
+}
+
+
+#define checkopenop(pt,pc)	luaG_checkopenop((pt)->code[(pc)+1])
+
+int luaG_checkopenop (Instruction i) {
+  switch (GET_OPCODE(i)) {
+    case OP_CALL:
+    case OP_TAILCALL:
+    case OP_RETURN:
+    case OP_SETLIST: {
+      check(GETARG_B(i) == 0);
+      return 1;
+    }
+    default: return 0;  /* invalid instruction after an open call */
+  }
+}
+
+
+static int checkArgMode (const Proto *pt, int r, enum OpArgMask mode) {
+  switch (mode) {
+    case OpArgN: check(r == 0); break;
+    case OpArgU: break;
+    case OpArgR: checkreg(pt, r); break;
+    case OpArgK:
+      check(ISK(r) ? INDEXK(r) < pt->sizek : r < pt->maxstacksize);
+      break;
+  }
+  return 1;
+}
+
+
+static Instruction symbexec (const Proto *pt, int lastpc, int reg) {
+  int pc;
+  int last;  /* stores position of last instruction that changed `reg' */
+  last = pt->sizecode-1;  /* points to final return (a `neutral' instruction) */
+  check(precheck(pt));
+  for (pc = 0; pc < lastpc; pc++) {
+    Instruction i = pt->code[pc];
+    OpCode op = GET_OPCODE(i);
+    int a = GETARG_A(i);
+    int b = 0;
+    int c = 0;
+    check(op < NUM_OPCODES);
+    checkreg(pt, a);
+    switch (getOpMode(op)) {
+      case iABC: {
+        b = GETARG_B(i);
+        c = GETARG_C(i);
+        check(checkArgMode(pt, b, getBMode(op)));
+        check(checkArgMode(pt, c, getCMode(op)));
+        break;
+      }
+      case iABx: {
+        b = GETARG_Bx(i);
+        if (getBMode(op) == OpArgK) check(b < pt->sizek);
+        break;
+      }
+      case iAsBx: {
+        b = GETARG_sBx(i);
+        if (getBMode(op) == OpArgR) {
+          int dest = pc+1+b;
+          check(0 <= dest && dest < pt->sizecode);
+          if (dest > 0) {
+            int j;
+            /* check that it does not jump to a setlist count; this
+               is tricky, because the count from a previous setlist may
+               have the same value of an invalid setlist; so, we must
+               go all the way back to the first of them (if any) */
+            for (j = 0; j < dest; j++) {
+              Instruction d = pt->code[dest-1-j];
+              if (!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0)) break;
+            }
+            /* if 'j' is even, previous value is not a setlist (even if
+               it looks like one) */
+            check((j&1) == 0);
+          }
+        }
+        break;
+      }
+    }
+    if (testAMode(op)) {
+      if (a == reg) last = pc;  /* change register `a' */
+    }
+    if (testTMode(op)) {
+      check(pc+2 < pt->sizecode);  /* check skip */
+      check(GET_OPCODE(pt->code[pc+1]) == OP_JMP);
+    }
+    switch (op) {
+      case OP_LOADBOOL: {
+        if (c == 1) {  /* does it jump? */
+          check(pc+2 < pt->sizecode);  /* check its jump */
+          check(GET_OPCODE(pt->code[pc+1]) != OP_SETLIST ||
+                GETARG_C(pt->code[pc+1]) != 0);
+        }
+        break;
+      }
+      case OP_LOADNIL: {
+        if (a <= reg && reg <= b)
+          last = pc;  /* set registers from `a' to `b' */
+        break;
+      }
+      case OP_GETUPVAL:
+      case OP_SETUPVAL: {
+        check(b < pt->nups);
+        break;
+      }
+      case OP_GETGLOBAL:
+      case OP_SETGLOBAL: {
+        check(ttisstring(&pt->k[b]));
+        break;
+      }
+      case OP_SELF: {
+        checkreg(pt, a+1);
+        if (reg == a+1) last = pc;
+        break;
+      }
+      case OP_CONCAT: {
+        check(b < c);  /* at least two operands */
+        break;
+      }
+      case OP_TFORLOOP: {
+        check(c >= 1);  /* at least one result (control variable) */
+        checkreg(pt, a+2+c);  /* space for results */
+        if (reg >= a+2) last = pc;  /* affect all regs above its base */
+        break;
+      }
+      case OP_FORLOOP:
+      case OP_FORPREP:
+        checkreg(pt, a+3);
+        /* go through */
+      case OP_JMP: {
+        int dest = pc+1+b;
+        /* not full check and jump is forward and do not skip `lastpc'? */
+        if (reg != NO_REG && pc < dest && dest <= lastpc)
+          pc += b;  /* do the jump */
+        break;
+      }
+      case OP_CALL:
+      case OP_TAILCALL: {
+        if (b != 0) {
+          checkreg(pt, a+b-1);
+        }
+        c--;  /* c = num. returns */
+        if (c == LUA_MULTRET) {
+          check(checkopenop(pt, pc));
+        }
+        else if (c != 0)
+          checkreg(pt, a+c-1);
+        if (reg >= a) last = pc;  /* affect all registers above base */
+        break;
+      }
+      case OP_RETURN: {
+        b--;  /* b = num. returns */
+        if (b > 0) checkreg(pt, a+b-1);
+        break;
+      }
+      case OP_SETLIST: {
+        if (b > 0) checkreg(pt, a + b);
+        if (c == 0) {
+          pc++;
+          check(pc < pt->sizecode - 1);
+        }
+        break;
+      }
+      case OP_CLOSURE: {
+        int nup, j;
+        check(b < pt->sizep);
+        nup = pt->p[b]->nups;
+        check(pc + nup < pt->sizecode);
+        for (j = 1; j <= nup; j++) {
+          OpCode op1 = GET_OPCODE(pt->code[pc + j]);
+          check(op1 == OP_GETUPVAL || op1 == OP_MOVE);
+        }
+        if (reg != NO_REG)  /* tracing? */
+          pc += nup;  /* do not 'execute' these pseudo-instructions */
+        break;
+      }
+      case OP_VARARG: {
+        check((pt->is_vararg & VARARG_ISVARARG) &&
+             !(pt->is_vararg & VARARG_NEEDSARG));
+        b--;
+        if (b == LUA_MULTRET) check(checkopenop(pt, pc));
+        checkreg(pt, a+b-1);
+        break;
+      }
+      default: break;
+    }
+  }
+  return pt->code[last];
+}
+
+#undef check
+#undef checkjump
+#undef checkreg
+
+/* }====================================================== */
+
+
+int luaG_checkcode (const Proto *pt) {
+  return (symbexec(pt, pt->sizecode, NO_REG) != 0);
+}
+
+
+static const char *kname (Proto *p, int c) {
+  if (ISK(c) && ttisstring(&p->k[INDEXK(c)]))
+    return svalue(&p->k[INDEXK(c)]);
+  else
+    return "?";
+}
+
+
+static const char *getobjname (lua_State *L, CallInfo *ci, int stackpos,
+                               const char **name) {
+  if (isLua(ci)) {  /* a Lua function? */
+    Proto *p = ci_func(ci)->l.p;
+    int pc = currentpc(L, ci);
+    Instruction i;
+    *name = luaF_getlocalname(p, stackpos+1, pc);
+    if (*name)  /* is a local? */
+      return "local";
+    i = symbexec(p, pc, stackpos);  /* try symbolic execution */
+    lua_assert(pc != -1);
+    switch (GET_OPCODE(i)) {
+      case OP_GETGLOBAL: {
+        int g = GETARG_Bx(i);  /* global index */
+        lua_assert(ttisstring(&p->k[g]));
+        *name = svalue(&p->k[g]);
+        return "global";
+      }
+      case OP_MOVE: {
+        int a = GETARG_A(i);
+        int b = GETARG_B(i);  /* move from `b' to `a' */
+        if (b < a)
+          return getobjname(L, ci, b, name);  /* get name for `b' */
+        break;
+      }
+      case OP_GETTABLE: {
+        int k = GETARG_C(i);  /* key index */
+        *name = kname(p, k);
+        return "field";
+      }
+      case OP_GETUPVAL: {
+        int u = GETARG_B(i);  /* upvalue index */
+        *name = p->upvalues ? getstr(p->upvalues[u]) : "?";
+        return "upvalue";
+      }
+      case OP_SELF: {
+        int k = GETARG_C(i);  /* key index */
+        *name = kname(p, k);
+        return "method";
+      }
+      default: break;
+    }
+  }
+  return NULL;  /* no useful name found */
+}
+
+
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
+  Instruction i;
+  if ((isLua(ci) && ci->tailcalls > 0) || !isLua(ci - 1))
+    return NULL;  /* calling function is not Lua (or is unknown) */
+  ci--;  /* calling function */
+  i = ci_func(ci)->l.p->code[currentpc(L, ci)];
+  if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL ||
+      GET_OPCODE(i) == OP_TFORLOOP)
+    return getobjname(L, ci, GETARG_A(i), name);
+  else
+    return NULL;  /* no useful name can be found */
+}
+
+
+/* only ANSI way to check whether a pointer points to an array */
+static int isinstack (CallInfo *ci, const TValue *o) {
+  StkId p;
+  for (p = ci->base; p < ci->top; p++)
+    if (o == p) return 1;
+  return 0;
+}
+
+
+void luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
+  const char *name = NULL;
+  const char *t = luaT_typenames[ttype(o)];
+  const char *kind = (isinstack(L->ci, o)) ?
+                         getobjname(L, L->ci, cast_int(o - L->base), &name) :
+                         NULL;
+  if (kind)
+    luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)",
+                op, kind, name, t);
+  else
+    luaG_runerror(L, "attempt to %s a %s value", op, t);
+}
+
+
+void luaG_concaterror (lua_State *L, StkId p1, StkId p2) {
+  if (ttisstring(p1) || ttisnumber(p1)) p1 = p2;
+  lua_assert(!ttisstring(p1) && !ttisnumber(p1));
+  luaG_typeerror(L, p1, "concatenate");
+}
+
+
+void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
+  TValue temp;
+  if (luaV_tonumber(p1, &temp) == NULL)
+    p2 = p1;  /* first operand is wrong */
+  luaG_typeerror(L, p2, "perform arithmetic on");
+}
+
+
+int luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
+  const char *t1 = luaT_typenames[ttype(p1)];
+  const char *t2 = luaT_typenames[ttype(p2)];
+  if (t1[2] == t2[2])
+    luaG_runerror(L, "attempt to compare two %s values", t1);
+  else
+    luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
+  return 0;
+}
+
+
+static void addinfo (lua_State *L, const char *msg) {
+  CallInfo *ci = L->ci;
+  if (isLua(ci)) {  /* is Lua code? */
+    char buff[LUA_IDSIZE];  /* add file:line information */
+    int line = currentline(L, ci);
+    luaO_chunkid(buff, getstr(getluaproto(ci)->source), LUA_IDSIZE);
+    luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
+  }
+}
+
+
+void luaG_errormsg (lua_State *L) {
+  if (L->errfunc != 0) {  /* is there an error handling function? */
+    StkId errfunc = restorestack(L, L->errfunc);
+    if (!ttisfunction(errfunc)) luaD_throw(L, LUA_ERRERR);
+    setobjs2s(L, L->top, L->top - 1);  /* move argument */
+    setobjs2s(L, L->top - 1, errfunc);  /* push function */
+    incr_top(L);
+    luaD_call(L, L->top - 2, 1);  /* call it */
+  }
+  luaD_throw(L, LUA_ERRRUN);
+}
+
+
+void luaG_runerror (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  addinfo(L, luaO_pushvfstring(L, fmt, argp));
+  va_end(argp);
+  luaG_errormsg(L);
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/ldebug.h b/third_party/lua-src/lua-5.1.5/ldebug.h
new file mode 100644
index 00000000..ba28a972
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ldebug.h
@@ -0,0 +1,33 @@
+/*
+** $Id: ldebug.h,v 2.3.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions from Debug Interface module
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ldebug_h
+#define ldebug_h
+
+
+#include "lstate.h"
+
+
+#define pcRel(pc, p)	(cast(int, (pc) - (p)->code) - 1)
+
+#define getline(f,pc)	(((f)->lineinfo) ? (f)->lineinfo[pc] : 0)
+
+#define resethookcount(L)	(L->hookcount = L->basehookcount)
+
+
+LUAI_FUNC void luaG_typeerror (lua_State *L, const TValue *o,
+                                             const char *opname);
+LUAI_FUNC void luaG_concaterror (lua_State *L, StkId p1, StkId p2);
+LUAI_FUNC void luaG_aritherror (lua_State *L, const TValue *p1,
+                                              const TValue *p2);
+LUAI_FUNC int luaG_ordererror (lua_State *L, const TValue *p1,
+                                             const TValue *p2);
+LUAI_FUNC void luaG_runerror (lua_State *L, const char *fmt, ...);
+LUAI_FUNC void luaG_errormsg (lua_State *L);
+LUAI_FUNC int luaG_checkcode (const Proto *pt);
+LUAI_FUNC int luaG_checkopenop (Instruction i);
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/ldo.c b/third_party/lua-src/lua-5.1.5/ldo.c
new file mode 100644
index 00000000..3af267f9
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ldo.c
@@ -0,0 +1,519 @@
+/*
+** $Id: ldo.c,v 2.38.1.4 2012/01/18 02:27:10 roberto Exp $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <setjmp.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldo_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+#include "lzio.h"
+
+
+
+
+/*
+** {======================================================
+** Error-recovery functions
+** =======================================================
+*/
+
+
+/* chain list of long jump buffers */
+struct lua_longjmp {
+  struct lua_longjmp *previous;
+  luai_jmpbuf b;
+  volatile int status;  /* error code */
+};
+
+
+void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+  switch (errcode) {
+    case LUA_ERRMEM: {
+      setsvalue2s(L, oldtop, luaS_newliteral(L, MEMERRMSG));
+      break;
+    }
+    case LUA_ERRERR: {
+      setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
+      break;
+    }
+    case LUA_ERRSYNTAX:
+    case LUA_ERRRUN: {
+      setobjs2s(L, oldtop, L->top - 1);  /* error message on current top */
+      break;
+    }
+  }
+  L->top = oldtop + 1;
+}
+
+
+static void restore_stack_limit (lua_State *L) {
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
+  if (L->size_ci > LUAI_MAXCALLS) {  /* there was an overflow? */
+    int inuse = cast_int(L->ci - L->base_ci);
+    if (inuse + 1 < LUAI_MAXCALLS)  /* can `undo' overflow? */
+      luaD_reallocCI(L, LUAI_MAXCALLS);
+  }
+}
+
+
+static void resetstack (lua_State *L, int status) {
+  L->ci = L->base_ci;
+  L->base = L->ci->base;
+  luaF_close(L, L->base);  /* close eventual pending closures */
+  luaD_seterrorobj(L, status, L->base);
+  L->nCcalls = L->baseCcalls;
+  L->allowhook = 1;
+  restore_stack_limit(L);
+  L->errfunc = 0;
+  L->errorJmp = NULL;
+}
+
+
+void luaD_throw (lua_State *L, int errcode) {
+  if (L->errorJmp) {
+    L->errorJmp->status = errcode;
+    LUAI_THROW(L, L->errorJmp);
+  }
+  else {
+    L->status = cast_byte(errcode);
+    if (G(L)->panic) {
+      resetstack(L, errcode);
+      lua_unlock(L);
+      G(L)->panic(L);
+    }
+    exit(EXIT_FAILURE);
+  }
+}
+
+
+int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
+  struct lua_longjmp lj;
+  lj.status = 0;
+  lj.previous = L->errorJmp;  /* chain new error handler */
+  L->errorJmp = &lj;
+  LUAI_TRY(L, &lj,
+    (*f)(L, ud);
+  );
+  L->errorJmp = lj.previous;  /* restore old error handler */
+  return lj.status;
+}
+
+/* }====================================================== */
+
+
+static void correctstack (lua_State *L, TValue *oldstack) {
+  CallInfo *ci;
+  GCObject *up;
+  L->top = (L->top - oldstack) + L->stack;
+  for (up = L->openupval; up != NULL; up = up->gch.next)
+    gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack;
+  for (ci = L->base_ci; ci <= L->ci; ci++) {
+    ci->top = (ci->top - oldstack) + L->stack;
+    ci->base = (ci->base - oldstack) + L->stack;
+    ci->func = (ci->func - oldstack) + L->stack;
+  }
+  L->base = (L->base - oldstack) + L->stack;
+}
+
+
+void luaD_reallocstack (lua_State *L, int newsize) {
+  TValue *oldstack = L->stack;
+  int realsize = newsize + 1 + EXTRA_STACK;
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
+  luaM_reallocvector(L, L->stack, L->stacksize, realsize, TValue);
+  L->stacksize = realsize;
+  L->stack_last = L->stack+newsize;
+  correctstack(L, oldstack);
+}
+
+
+void luaD_reallocCI (lua_State *L, int newsize) {
+  CallInfo *oldci = L->base_ci;
+  luaM_reallocvector(L, L->base_ci, L->size_ci, newsize, CallInfo);
+  L->size_ci = newsize;
+  L->ci = (L->ci - oldci) + L->base_ci;
+  L->end_ci = L->base_ci + L->size_ci - 1;
+}
+
+
+void luaD_growstack (lua_State *L, int n) {
+  if (n <= L->stacksize)  /* double size is enough? */
+    luaD_reallocstack(L, 2*L->stacksize);
+  else
+    luaD_reallocstack(L, L->stacksize + n);
+}
+
+
+static CallInfo *growCI (lua_State *L) {
+  if (L->size_ci > LUAI_MAXCALLS)  /* overflow while handling overflow? */
+    luaD_throw(L, LUA_ERRERR);
+  else {
+    luaD_reallocCI(L, 2*L->size_ci);
+    if (L->size_ci > LUAI_MAXCALLS)
+      luaG_runerror(L, "stack overflow");
+  }
+  return ++L->ci;
+}
+
+
+void luaD_callhook (lua_State *L, int event, int line) {
+  lua_Hook hook = L->hook;
+  if (hook && L->allowhook) {
+    ptrdiff_t top = savestack(L, L->top);
+    ptrdiff_t ci_top = savestack(L, L->ci->top);
+    lua_Debug ar;
+    ar.event = event;
+    ar.currentline = line;
+    if (event == LUA_HOOKTAILRET)
+      ar.i_ci = 0;  /* tail call; no debug information about it */
+    else
+      ar.i_ci = cast_int(L->ci - L->base_ci);
+    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+    L->ci->top = L->top + LUA_MINSTACK;
+    lua_assert(L->ci->top <= L->stack_last);
+    L->allowhook = 0;  /* cannot call hooks inside a hook */
+    lua_unlock(L);
+    (*hook)(L, &ar);
+    lua_lock(L);
+    lua_assert(!L->allowhook);
+    L->allowhook = 1;
+    L->ci->top = restorestack(L, ci_top);
+    L->top = restorestack(L, top);
+  }
+}
+
+
+static StkId adjust_varargs (lua_State *L, Proto *p, int actual) {
+  int i;
+  int nfixargs = p->numparams;
+  Table *htab = NULL;
+  StkId base, fixed;
+  for (; actual < nfixargs; ++actual)
+    setnilvalue(L->top++);
+#if defined(LUA_COMPAT_VARARG)
+  if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */
+    int nvar = actual - nfixargs;  /* number of extra arguments */
+    lua_assert(p->is_vararg & VARARG_HASARG);
+    luaC_checkGC(L);
+    luaD_checkstack(L, p->maxstacksize);
+    htab = luaH_new(L, nvar, 1);  /* create `arg' table */
+    for (i=0; i<nvar; i++)  /* put extra arguments into `arg' table */
+      setobj2n(L, luaH_setnum(L, htab, i+1), L->top - nvar + i);
+    /* store counter in field `n' */
+    setnvalue(luaH_setstr(L, htab, luaS_newliteral(L, "n")), cast_num(nvar));
+  }
+#endif
+  /* move fixed parameters to final position */
+  fixed = L->top - actual;  /* first fixed argument */
+  base = L->top;  /* final position of first argument */
+  for (i=0; i<nfixargs; i++) {
+    setobjs2s(L, L->top++, fixed+i);
+    setnilvalue(fixed+i);
+  }
+  /* add `arg' parameter */
+  if (htab) {
+    sethvalue(L, L->top++, htab);
+    lua_assert(iswhite(obj2gco(htab)));
+  }
+  return base;
+}
+
+
+static StkId tryfuncTM (lua_State *L, StkId func) {
+  const TValue *tm = luaT_gettmbyobj(L, func, TM_CALL);
+  StkId p;
+  ptrdiff_t funcr = savestack(L, func);
+  if (!ttisfunction(tm))
+    luaG_typeerror(L, func, "call");
+  /* Open a hole inside the stack at `func' */
+  for (p = L->top; p > func; p--) setobjs2s(L, p, p-1);
+  incr_top(L);
+  func = restorestack(L, funcr);  /* previous call may change stack */
+  setobj2s(L, func, tm);  /* tag method is the new function to be called */
+  return func;
+}
+
+
+
+#define inc_ci(L) \
+  ((L->ci == L->end_ci) ? growCI(L) : \
+   (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci))
+
+
+int luaD_precall (lua_State *L, StkId func, int nresults) {
+  LClosure *cl;
+  ptrdiff_t funcr;
+  if (!ttisfunction(func)) /* `func' is not a function? */
+    func = tryfuncTM(L, func);  /* check the `function' tag method */
+  funcr = savestack(L, func);
+  cl = &clvalue(func)->l;
+  L->ci->savedpc = L->savedpc;
+  if (!cl->isC) {  /* Lua function? prepare its call */
+    CallInfo *ci;
+    StkId st, base;
+    Proto *p = cl->p;
+    luaD_checkstack(L, p->maxstacksize + p->numparams);
+    func = restorestack(L, funcr);
+    if (!p->is_vararg) {  /* no varargs? */
+      base = func + 1;
+      if (L->top > base + p->numparams)
+        L->top = base + p->numparams;
+    }
+    else {  /* vararg function */
+      int nargs = cast_int(L->top - func) - 1;
+      base = adjust_varargs(L, p, nargs);
+      func = restorestack(L, funcr);  /* previous call may change the stack */
+    }
+    ci = inc_ci(L);  /* now `enter' new function */
+    ci->func = func;
+    L->base = ci->base = base;
+    ci->top = L->base + p->maxstacksize;
+    lua_assert(ci->top <= L->stack_last);
+    L->savedpc = p->code;  /* starting point */
+    ci->tailcalls = 0;
+    ci->nresults = nresults;
+    for (st = L->top; st < ci->top; st++)
+      setnilvalue(st);
+    L->top = ci->top;
+    if (L->hookmask & LUA_MASKCALL) {
+      L->savedpc++;  /* hooks assume 'pc' is already incremented */
+      luaD_callhook(L, LUA_HOOKCALL, -1);
+      L->savedpc--;  /* correct 'pc' */
+    }
+    return PCRLUA;
+  }
+  else {  /* if is a C function, call it */
+    CallInfo *ci;
+    int n;
+    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+    ci = inc_ci(L);  /* now `enter' new function */
+    ci->func = restorestack(L, funcr);
+    L->base = ci->base = ci->func + 1;
+    ci->top = L->top + LUA_MINSTACK;
+    lua_assert(ci->top <= L->stack_last);
+    ci->nresults = nresults;
+    if (L->hookmask & LUA_MASKCALL)
+      luaD_callhook(L, LUA_HOOKCALL, -1);
+    lua_unlock(L);
+    n = (*curr_func(L)->c.f)(L);  /* do the actual call */
+    lua_lock(L);
+    if (n < 0)  /* yielding? */
+      return PCRYIELD;
+    else {
+      luaD_poscall(L, L->top - n);
+      return PCRC;
+    }
+  }
+}
+
+
+static StkId callrethooks (lua_State *L, StkId firstResult) {
+  ptrdiff_t fr = savestack(L, firstResult);  /* next call may change stack */
+  luaD_callhook(L, LUA_HOOKRET, -1);
+  if (f_isLua(L->ci)) {  /* Lua function? */
+    while ((L->hookmask & LUA_MASKRET) && L->ci->tailcalls--) /* tail calls */
+      luaD_callhook(L, LUA_HOOKTAILRET, -1);
+  }
+  return restorestack(L, fr);
+}
+
+
+int luaD_poscall (lua_State *L, StkId firstResult) {
+  StkId res;
+  int wanted, i;
+  CallInfo *ci;
+  if (L->hookmask & LUA_MASKRET)
+    firstResult = callrethooks(L, firstResult);
+  ci = L->ci--;
+  res = ci->func;  /* res == final position of 1st result */
+  wanted = ci->nresults;
+  L->base = (ci - 1)->base;  /* restore base */
+  L->savedpc = (ci - 1)->savedpc;  /* restore savedpc */
+  /* move results to correct place */
+  for (i = wanted; i != 0 && firstResult < L->top; i--)
+    setobjs2s(L, res++, firstResult++);
+  while (i-- > 0)
+    setnilvalue(res++);
+  L->top = res;
+  return (wanted - LUA_MULTRET);  /* 0 iff wanted == LUA_MULTRET */
+}
+
+
+/*
+** Call a function (C or Lua). The function to be called is at *func.
+** The arguments are on the stack, right after the function.
+** When returns, all the results are on the stack, starting at the original
+** function position.
+*/
+void luaD_call (lua_State *L, StkId func, int nResults) {
+  if (++L->nCcalls >= LUAI_MAXCCALLS) {
+    if (L->nCcalls == LUAI_MAXCCALLS)
+      luaG_runerror(L, "C stack overflow");
+    else if (L->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3)))
+      luaD_throw(L, LUA_ERRERR);  /* error while handing stack error */
+  }
+  if (luaD_precall(L, func, nResults) == PCRLUA)  /* is a Lua function? */
+    luaV_execute(L, 1);  /* call it */
+  L->nCcalls--;
+  luaC_checkGC(L);
+}
+
+
+static void resume (lua_State *L, void *ud) {
+  StkId firstArg = cast(StkId, ud);
+  CallInfo *ci = L->ci;
+  if (L->status == 0) {  /* start coroutine? */
+    lua_assert(ci == L->base_ci && firstArg > L->base);
+    if (luaD_precall(L, firstArg - 1, LUA_MULTRET) != PCRLUA)
+      return;
+  }
+  else {  /* resuming from previous yield */
+    lua_assert(L->status == LUA_YIELD);
+    L->status = 0;
+    if (!f_isLua(ci)) {  /* `common' yield? */
+      /* finish interrupted execution of `OP_CALL' */
+      lua_assert(GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_CALL ||
+                 GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_TAILCALL);
+      if (luaD_poscall(L, firstArg))  /* complete it... */
+        L->top = L->ci->top;  /* and correct top if not multiple results */
+    }
+    else  /* yielded inside a hook: just continue its execution */
+      L->base = L->ci->base;
+  }
+  luaV_execute(L, cast_int(L->ci - L->base_ci));
+}
+
+
+static int resume_error (lua_State *L, const char *msg) {
+  L->top = L->ci->base;
+  setsvalue2s(L, L->top, luaS_new(L, msg));
+  incr_top(L);
+  lua_unlock(L);
+  return LUA_ERRRUN;
+}
+
+
+LUA_API int lua_resume (lua_State *L, int nargs) {
+  int status;
+  lua_lock(L);
+  if (L->status != LUA_YIELD && (L->status != 0 || L->ci != L->base_ci))
+      return resume_error(L, "cannot resume non-suspended coroutine");
+  if (L->nCcalls >= LUAI_MAXCCALLS)
+    return resume_error(L, "C stack overflow");
+  luai_userstateresume(L, nargs);
+  lua_assert(L->errfunc == 0);
+  L->baseCcalls = ++L->nCcalls;
+  status = luaD_rawrunprotected(L, resume, L->top - nargs);
+  if (status != 0) {  /* error? */
+    L->status = cast_byte(status);  /* mark thread as `dead' */
+    luaD_seterrorobj(L, status, L->top);
+    L->ci->top = L->top;
+  }
+  else {
+    lua_assert(L->nCcalls == L->baseCcalls);
+    status = L->status;
+  }
+  --L->nCcalls;
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_yield (lua_State *L, int nresults) {
+  luai_userstateyield(L, nresults);
+  lua_lock(L);
+  if (L->nCcalls > L->baseCcalls)
+    luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
+  L->base = L->top - nresults;  /* protect stack slots below */
+  L->status = LUA_YIELD;
+  lua_unlock(L);
+  return -1;
+}
+
+
+int luaD_pcall (lua_State *L, Pfunc func, void *u,
+                ptrdiff_t old_top, ptrdiff_t ef) {
+  int status;
+  unsigned short oldnCcalls = L->nCcalls;
+  ptrdiff_t old_ci = saveci(L, L->ci);
+  lu_byte old_allowhooks = L->allowhook;
+  ptrdiff_t old_errfunc = L->errfunc;
+  L->errfunc = ef;
+  status = luaD_rawrunprotected(L, func, u);
+  if (status != 0) {  /* an error occurred? */
+    StkId oldtop = restorestack(L, old_top);
+    luaF_close(L, oldtop);  /* close eventual pending closures */
+    luaD_seterrorobj(L, status, oldtop);
+    L->nCcalls = oldnCcalls;
+    L->ci = restoreci(L, old_ci);
+    L->base = L->ci->base;
+    L->savedpc = L->ci->savedpc;
+    L->allowhook = old_allowhooks;
+    restore_stack_limit(L);
+  }
+  L->errfunc = old_errfunc;
+  return status;
+}
+
+
+
+/*
+** Execute a protected parser.
+*/
+struct SParser {  /* data to `f_parser' */
+  ZIO *z;
+  Mbuffer buff;  /* buffer to be used by the scanner */
+  const char *name;
+};
+
+static void f_parser (lua_State *L, void *ud) {
+  int i;
+  Proto *tf;
+  Closure *cl;
+  struct SParser *p = cast(struct SParser *, ud);
+  int c = luaZ_lookahead(p->z);
+  luaC_checkGC(L);
+  tf = ((c == LUA_SIGNATURE[0]) ? luaU_undump : luaY_parser)(L, p->z,
+                                                             &p->buff, p->name);
+  cl = luaF_newLclosure(L, tf->nups, hvalue(gt(L)));
+  cl->l.p = tf;
+  for (i = 0; i < tf->nups; i++)  /* initialize eventual upvalues */
+    cl->l.upvals[i] = luaF_newupval(L);
+  setclvalue(L, L->top, cl);
+  incr_top(L);
+}
+
+
+int luaD_protectedparser (lua_State *L, ZIO *z, const char *name) {
+  struct SParser p;
+  int status;
+  p.z = z; p.name = name;
+  luaZ_initbuffer(L, &p.buff);
+  status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
+  luaZ_freebuffer(L, &p.buff);
+  return status;
+}
+
+
diff --git a/third_party/lua-src/lua-5.1.5/ldo.h b/third_party/lua-src/lua-5.1.5/ldo.h
new file mode 100644
index 00000000..98fddac5
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ldo.h
@@ -0,0 +1,57 @@
+/*
+** $Id: ldo.h,v 2.7.1.1 2007/12/27 13:02:25 roberto Exp $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ldo_h
+#define ldo_h
+
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lzio.h"
+
+
+#define luaD_checkstack(L,n)	\
+  if ((char *)L->stack_last - (char *)L->top <= (n)*(int)sizeof(TValue)) \
+    luaD_growstack(L, n); \
+  else condhardstacktests(luaD_reallocstack(L, L->stacksize - EXTRA_STACK - 1));
+
+
+#define incr_top(L) {luaD_checkstack(L,1); L->top++;}
+
+#define savestack(L,p)		((char *)(p) - (char *)L->stack)
+#define restorestack(L,n)	((TValue *)((char *)L->stack + (n)))
+
+#define saveci(L,p)		((char *)(p) - (char *)L->base_ci)
+#define restoreci(L,n)		((CallInfo *)((char *)L->base_ci + (n)))
+
+
+/* results from luaD_precall */
+#define PCRLUA		0	/* initiated a call to a Lua function */
+#define PCRC		1	/* did a call to a C function */
+#define PCRYIELD	2	/* C funtion yielded */
+
+
+/* type of protected functions, to be ran by `runprotected' */
+typedef void (*Pfunc) (lua_State *L, void *ud);
+
+LUAI_FUNC int luaD_protectedparser (lua_State *L, ZIO *z, const char *name);
+LUAI_FUNC void luaD_callhook (lua_State *L, int event, int line);
+LUAI_FUNC int luaD_precall (lua_State *L, StkId func, int nresults);
+LUAI_FUNC void luaD_call (lua_State *L, StkId func, int nResults);
+LUAI_FUNC int luaD_pcall (lua_State *L, Pfunc func, void *u,
+                                        ptrdiff_t oldtop, ptrdiff_t ef);
+LUAI_FUNC int luaD_poscall (lua_State *L, StkId firstResult);
+LUAI_FUNC void luaD_reallocCI (lua_State *L, int newsize);
+LUAI_FUNC void luaD_reallocstack (lua_State *L, int newsize);
+LUAI_FUNC void luaD_growstack (lua_State *L, int n);
+
+LUAI_FUNC void luaD_throw (lua_State *L, int errcode);
+LUAI_FUNC int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud);
+
+LUAI_FUNC void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop);
+
+#endif
+
diff --git a/third_party/lua-src/lua-5.1.5/ldump.c b/third_party/lua-src/lua-5.1.5/ldump.c
new file mode 100644
index 00000000..c9d3d487
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ldump.c
@@ -0,0 +1,164 @@
+/*
+** $Id: ldump.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** save precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#include <stddef.h>
+
+#define ldump_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lundump.h"
+
+typedef struct {
+ lua_State* L;
+ lua_Writer writer;
+ void* data;
+ int strip;
+ int status;
+} DumpState;
+
+#define DumpMem(b,n,size,D)	DumpBlock(b,(n)*(size),D)
+#define DumpVar(x,D)	 	DumpMem(&x,1,sizeof(x),D)
+
+static void DumpBlock(const void* b, size_t size, DumpState* D)
+{
+ if (D->status==0)
+ {
+  lua_unlock(D->L);
+  D->status=(*D->writer)(D->L,b,size,D->data);
+  lua_lock(D->L);
+ }
+}
+
+static void DumpChar(int y, DumpState* D)
+{
+ char x=(char)y;
+ DumpVar(x,D);
+}
+
+static void DumpInt(int x, DumpState* D)
+{
+ DumpVar(x,D);
+}
+
+static void DumpNumber(lua_Number x, DumpState* D)
+{
+ DumpVar(x,D);
+}
+
+static void DumpVector(const void* b, int n, size_t size, DumpState* D)
+{
+ DumpInt(n,D);
+ DumpMem(b,n,size,D);
+}
+
+static void DumpString(const TString* s, DumpState* D)
+{
+ if (s==NULL || getstr(s)==NULL)
+ {
+  size_t size=0;
+  DumpVar(size,D);
+ }
+ else
+ {
+  size_t size=s->tsv.len+1;		/* include trailing '\0' */
+  DumpVar(size,D);
+  DumpBlock(getstr(s),size,D);
+ }
+}
+
+#define DumpCode(f,D)	 DumpVector(f->code,f->sizecode,sizeof(Instruction),D)
+
+static void DumpFunction(const Proto* f, const TString* p, DumpState* D);
+
+static void DumpConstants(const Proto* f, DumpState* D)
+{
+ int i,n=f->sizek;
+ DumpInt(n,D);
+ for (i=0; i<n; i++)
+ {
+  const TValue* o=&f->k[i];
+  DumpChar(ttype(o),D);
+  switch (ttype(o))
+  {
+   case LUA_TNIL:
+	break;
+   case LUA_TBOOLEAN:
+	DumpChar(bvalue(o),D);
+	break;
+   case LUA_TNUMBER:
+	DumpNumber(nvalue(o),D);
+	break;
+   case LUA_TSTRING:
+	DumpString(rawtsvalue(o),D);
+	break;
+   default:
+	lua_assert(0);			/* cannot happen */
+	break;
+  }
+ }
+ n=f->sizep;
+ DumpInt(n,D);
+ for (i=0; i<n; i++) DumpFunction(f->p[i],f->source,D);
+}
+
+static void DumpDebug(const Proto* f, DumpState* D)
+{
+ int i,n;
+ n= (D->strip) ? 0 : f->sizelineinfo;
+ DumpVector(f->lineinfo,n,sizeof(int),D);
+ n= (D->strip) ? 0 : f->sizelocvars;
+ DumpInt(n,D);
+ for (i=0; i<n; i++)
+ {
+  DumpString(f->locvars[i].varname,D);
+  DumpInt(f->locvars[i].startpc,D);
+  DumpInt(f->locvars[i].endpc,D);
+ }
+ n= (D->strip) ? 0 : f->sizeupvalues;
+ DumpInt(n,D);
+ for (i=0; i<n; i++) DumpString(f->upvalues[i],D);
+}
+
+static void DumpFunction(const Proto* f, const TString* p, DumpState* D)
+{
+ DumpString((f->source==p || D->strip) ? NULL : f->source,D);
+ DumpInt(f->linedefined,D);
+ DumpInt(f->lastlinedefined,D);
+ DumpChar(f->nups,D);
+ DumpChar(f->numparams,D);
+ DumpChar(f->is_vararg,D);
+ DumpChar(f->maxstacksize,D);
+ DumpCode(f,D);
+ DumpConstants(f,D);
+ DumpDebug(f,D);
+}
+
+static void DumpHeader(DumpState* D)
+{
+ char h[LUAC_HEADERSIZE];
+ luaU_header(h);
+ DumpBlock(h,LUAC_HEADERSIZE,D);
+}
+
+/*
+** dump Lua function as precompiled chunk
+*/
+int luaU_dump (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip)
+{
+ DumpState D;
+ D.L=L;
+ D.writer=w;
+ D.data=data;
+ D.strip=strip;
+ D.status=0;
+ DumpHeader(&D);
+ DumpFunction(f,NULL,&D);
+ return D.status;
+}
diff --git a/third_party/lua-src/lua-5.1.5/lfunc.c b/third_party/lua-src/lua-5.1.5/lfunc.c
new file mode 100644
index 00000000..813e88f5
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lfunc.c
@@ -0,0 +1,174 @@
+/*
+** $Id: lfunc.c,v 2.12.1.2 2007/12/28 14:58:43 roberto Exp $
+** Auxiliary functions to manipulate prototypes and closures
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define lfunc_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+
+Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
+  Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
+  luaC_link(L, obj2gco(c), LUA_TFUNCTION);
+  c->c.isC = 1;
+  c->c.env = e;
+  c->c.nupvalues = cast_byte(nelems);
+  return c;
+}
+
+
+Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e) {
+  Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
+  luaC_link(L, obj2gco(c), LUA_TFUNCTION);
+  c->l.isC = 0;
+  c->l.env = e;
+  c->l.nupvalues = cast_byte(nelems);
+  while (nelems--) c->l.upvals[nelems] = NULL;
+  return c;
+}
+
+
+UpVal *luaF_newupval (lua_State *L) {
+  UpVal *uv = luaM_new(L, UpVal);
+  luaC_link(L, obj2gco(uv), LUA_TUPVAL);
+  uv->v = &uv->u.value;
+  setnilvalue(uv->v);
+  return uv;
+}
+
+
+UpVal *luaF_findupval (lua_State *L, StkId level) {
+  global_State *g = G(L);
+  GCObject **pp = &L->openupval;
+  UpVal *p;
+  UpVal *uv;
+  while (*pp != NULL && (p = ngcotouv(*pp))->v >= level) {
+    lua_assert(p->v != &p->u.value);
+    if (p->v == level) {  /* found a corresponding upvalue? */
+      if (isdead(g, obj2gco(p)))  /* is it dead? */
+        changewhite(obj2gco(p));  /* ressurect it */
+      return p;
+    }
+    pp = &p->next;
+  }
+  uv = luaM_new(L, UpVal);  /* not found: create a new one */
+  uv->tt = LUA_TUPVAL;
+  uv->marked = luaC_white(g);
+  uv->v = level;  /* current value lives in the stack */
+  uv->next = *pp;  /* chain it in the proper position */
+  *pp = obj2gco(uv);
+  uv->u.l.prev = &g->uvhead;  /* double link it in `uvhead' list */
+  uv->u.l.next = g->uvhead.u.l.next;
+  uv->u.l.next->u.l.prev = uv;
+  g->uvhead.u.l.next = uv;
+  lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
+  return uv;
+}
+
+
+static void unlinkupval (UpVal *uv) {
+  lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
+  uv->u.l.next->u.l.prev = uv->u.l.prev;  /* remove from `uvhead' list */
+  uv->u.l.prev->u.l.next = uv->u.l.next;
+}
+
+
+void luaF_freeupval (lua_State *L, UpVal *uv) {
+  if (uv->v != &uv->u.value)  /* is it open? */
+    unlinkupval(uv);  /* remove from open list */
+  luaM_free(L, uv);  /* free upvalue */
+}
+
+
+void luaF_close (lua_State *L, StkId level) {
+  UpVal *uv;
+  global_State *g = G(L);
+  while (L->openupval != NULL && (uv = ngcotouv(L->openupval))->v >= level) {
+    GCObject *o = obj2gco(uv);
+    lua_assert(!isblack(o) && uv->v != &uv->u.value);
+    L->openupval = uv->next;  /* remove from `open' list */
+    if (isdead(g, o))
+      luaF_freeupval(L, uv);  /* free upvalue */
+    else {
+      unlinkupval(uv);
+      setobj(L, &uv->u.value, uv->v);
+      uv->v = &uv->u.value;  /* now current value lives here */
+      luaC_linkupval(L, uv);  /* link upvalue into `gcroot' list */
+    }
+  }
+}
+
+
+Proto *luaF_newproto (lua_State *L) {
+  Proto *f = luaM_new(L, Proto);
+  luaC_link(L, obj2gco(f), LUA_TPROTO);
+  f->k = NULL;
+  f->sizek = 0;
+  f->p = NULL;
+  f->sizep = 0;
+  f->code = NULL;
+  f->sizecode = 0;
+  f->sizelineinfo = 0;
+  f->sizeupvalues = 0;
+  f->nups = 0;
+  f->upvalues = NULL;
+  f->numparams = 0;
+  f->is_vararg = 0;
+  f->maxstacksize = 0;
+  f->lineinfo = NULL;
+  f->sizelocvars = 0;
+  f->locvars = NULL;
+  f->linedefined = 0;
+  f->lastlinedefined = 0;
+  f->source = NULL;
+  return f;
+}
+
+
+void luaF_freeproto (lua_State *L, Proto *f) {
+  luaM_freearray(L, f->code, f->sizecode, Instruction);
+  luaM_freearray(L, f->p, f->sizep, Proto *);
+  luaM_freearray(L, f->k, f->sizek, TValue);
+  luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
+  luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
+  luaM_freearray(L, f->upvalues, f->sizeupvalues, TString *);
+  luaM_free(L, f);
+}
+
+
+void luaF_freeclosure (lua_State *L, Closure *c) {
+  int size = (c->c.isC) ? sizeCclosure(c->c.nupvalues) :
+                          sizeLclosure(c->l.nupvalues);
+  luaM_freemem(L, c, size);
+}
+
+
+/*
+** Look for n-th local variable at line `line' in function `func'.
+** Returns NULL if not found.
+*/
+const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
+  int i;
+  for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
+    if (pc < f->locvars[i].endpc) {  /* is variable active? */
+      local_number--;
+      if (local_number == 0)
+        return getstr(f->locvars[i].varname);
+    }
+  }
+  return NULL;  /* not found */
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lfunc.h b/third_party/lua-src/lua-5.1.5/lfunc.h
new file mode 100644
index 00000000..a68cf515
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lfunc.h
@@ -0,0 +1,34 @@
+/*
+** $Id: lfunc.h,v 2.4.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions to manipulate prototypes and closures
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lfunc_h
+#define lfunc_h
+
+
+#include "lobject.h"
+
+
+#define sizeCclosure(n)	(cast(int, sizeof(CClosure)) + \
+                         cast(int, sizeof(TValue)*((n)-1)))
+
+#define sizeLclosure(n)	(cast(int, sizeof(LClosure)) + \
+                         cast(int, sizeof(TValue *)*((n)-1)))
+
+
+LUAI_FUNC Proto *luaF_newproto (lua_State *L);
+LUAI_FUNC Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e);
+LUAI_FUNC Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e);
+LUAI_FUNC UpVal *luaF_newupval (lua_State *L);
+LUAI_FUNC UpVal *luaF_findupval (lua_State *L, StkId level);
+LUAI_FUNC void luaF_close (lua_State *L, StkId level);
+LUAI_FUNC void luaF_freeproto (lua_State *L, Proto *f);
+LUAI_FUNC void luaF_freeclosure (lua_State *L, Closure *c);
+LUAI_FUNC void luaF_freeupval (lua_State *L, UpVal *uv);
+LUAI_FUNC const char *luaF_getlocalname (const Proto *func, int local_number,
+                                         int pc);
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lgc.c b/third_party/lua-src/lua-5.1.5/lgc.c
new file mode 100644
index 00000000..e909c79a
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lgc.c
@@ -0,0 +1,710 @@
+/*
+** $Id: lgc.c,v 2.38.1.2 2011/03/18 18:05:38 roberto Exp $
+** Garbage Collector
+** See Copyright Notice in lua.h
+*/
+
+#include <string.h>
+
+#define lgc_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+#define GCSTEPSIZE	1024u
+#define GCSWEEPMAX	40
+#define GCSWEEPCOST	10
+#define GCFINALIZECOST	100
+
+
+#define maskmarks	cast_byte(~(bitmask(BLACKBIT)|WHITEBITS))
+
+#define makewhite(g,x)	\
+   ((x)->gch.marked = cast_byte(((x)->gch.marked & maskmarks) | luaC_white(g)))
+
+#define white2gray(x)	reset2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT)
+#define black2gray(x)	resetbit((x)->gch.marked, BLACKBIT)
+
+#define stringmark(s)	reset2bits((s)->tsv.marked, WHITE0BIT, WHITE1BIT)
+
+
+#define isfinalized(u)		testbit((u)->marked, FINALIZEDBIT)
+#define markfinalized(u)	l_setbit((u)->marked, FINALIZEDBIT)
+
+
+#define KEYWEAK         bitmask(KEYWEAKBIT)
+#define VALUEWEAK       bitmask(VALUEWEAKBIT)
+
+
+
+#define markvalue(g,o) { checkconsistency(o); \
+  if (iscollectable(o) && iswhite(gcvalue(o))) reallymarkobject(g,gcvalue(o)); }
+
+#define markobject(g,t) { if (iswhite(obj2gco(t))) \
+		reallymarkobject(g, obj2gco(t)); }
+
+
+#define setthreshold(g)  (g->GCthreshold = (g->estimate/100) * g->gcpause)
+
+
+static void removeentry (Node *n) {
+  lua_assert(ttisnil(gval(n)));
+  if (iscollectable(gkey(n)))
+    setttype(gkey(n), LUA_TDEADKEY);  /* dead key; remove it */
+}
+
+
+static void reallymarkobject (global_State *g, GCObject *o) {
+  lua_assert(iswhite(o) && !isdead(g, o));
+  white2gray(o);
+  switch (o->gch.tt) {
+    case LUA_TSTRING: {
+      return;
+    }
+    case LUA_TUSERDATA: {
+      Table *mt = gco2u(o)->metatable;
+      gray2black(o);  /* udata are never gray */
+      if (mt) markobject(g, mt);
+      markobject(g, gco2u(o)->env);
+      return;
+    }
+    case LUA_TUPVAL: {
+      UpVal *uv = gco2uv(o);
+      markvalue(g, uv->v);
+      if (uv->v == &uv->u.value)  /* closed? */
+        gray2black(o);  /* open upvalues are never black */
+      return;
+    }
+    case LUA_TFUNCTION: {
+      gco2cl(o)->c.gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    case LUA_TTABLE: {
+      gco2h(o)->gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    case LUA_TTHREAD: {
+      gco2th(o)->gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    case LUA_TPROTO: {
+      gco2p(o)->gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+static void marktmu (global_State *g) {
+  GCObject *u = g->tmudata;
+  if (u) {
+    do {
+      u = u->gch.next;
+      makewhite(g, u);  /* may be marked, if left from previous GC */
+      reallymarkobject(g, u);
+    } while (u != g->tmudata);
+  }
+}
+
+
+/* move `dead' udata that need finalization to list `tmudata' */
+size_t luaC_separateudata (lua_State *L, int all) {
+  global_State *g = G(L);
+  size_t deadmem = 0;
+  GCObject **p = &g->mainthread->next;
+  GCObject *curr;
+  while ((curr = *p) != NULL) {
+    if (!(iswhite(curr) || all) || isfinalized(gco2u(curr)))
+      p = &curr->gch.next;  /* don't bother with them */
+    else if (fasttm(L, gco2u(curr)->metatable, TM_GC) == NULL) {
+      markfinalized(gco2u(curr));  /* don't need finalization */
+      p = &curr->gch.next;
+    }
+    else {  /* must call its gc method */
+      deadmem += sizeudata(gco2u(curr));
+      markfinalized(gco2u(curr));
+      *p = curr->gch.next;
+      /* link `curr' at the end of `tmudata' list */
+      if (g->tmudata == NULL)  /* list is empty? */
+        g->tmudata = curr->gch.next = curr;  /* creates a circular list */
+      else {
+        curr->gch.next = g->tmudata->gch.next;
+        g->tmudata->gch.next = curr;
+        g->tmudata = curr;
+      }
+    }
+  }
+  return deadmem;
+}
+
+
+static int traversetable (global_State *g, Table *h) {
+  int i;
+  int weakkey = 0;
+  int weakvalue = 0;
+  const TValue *mode;
+  if (h->metatable)
+    markobject(g, h->metatable);
+  mode = gfasttm(g, h->metatable, TM_MODE);
+  if (mode && ttisstring(mode)) {  /* is there a weak mode? */
+    weakkey = (strchr(svalue(mode), 'k') != NULL);
+    weakvalue = (strchr(svalue(mode), 'v') != NULL);
+    if (weakkey || weakvalue) {  /* is really weak? */
+      h->marked &= ~(KEYWEAK | VALUEWEAK);  /* clear bits */
+      h->marked |= cast_byte((weakkey << KEYWEAKBIT) |
+                             (weakvalue << VALUEWEAKBIT));
+      h->gclist = g->weak;  /* must be cleared after GC, ... */
+      g->weak = obj2gco(h);  /* ... so put in the appropriate list */
+    }
+  }
+  if (weakkey && weakvalue) return 1;
+  if (!weakvalue) {
+    i = h->sizearray;
+    while (i--)
+      markvalue(g, &h->array[i]);
+  }
+  i = sizenode(h);
+  while (i--) {
+    Node *n = gnode(h, i);
+    lua_assert(ttype(gkey(n)) != LUA_TDEADKEY || ttisnil(gval(n)));
+    if (ttisnil(gval(n)))
+      removeentry(n);  /* remove empty entries */
+    else {
+      lua_assert(!ttisnil(gkey(n)));
+      if (!weakkey) markvalue(g, gkey(n));
+      if (!weakvalue) markvalue(g, gval(n));
+    }
+  }
+  return weakkey || weakvalue;
+}
+
+
+/*
+** All marks are conditional because a GC may happen while the
+** prototype is still being created
+*/
+static void traverseproto (global_State *g, Proto *f) {
+  int i;
+  if (f->source) stringmark(f->source);
+  for (i=0; i<f->sizek; i++)  /* mark literals */
+    markvalue(g, &f->k[i]);
+  for (i=0; i<f->sizeupvalues; i++) {  /* mark upvalue names */
+    if (f->upvalues[i])
+      stringmark(f->upvalues[i]);
+  }
+  for (i=0; i<f->sizep; i++) {  /* mark nested protos */
+    if (f->p[i])
+      markobject(g, f->p[i]);
+  }
+  for (i=0; i<f->sizelocvars; i++) {  /* mark local-variable names */
+    if (f->locvars[i].varname)
+      stringmark(f->locvars[i].varname);
+  }
+}
+
+
+
+static void traverseclosure (global_State *g, Closure *cl) {
+  markobject(g, cl->c.env);
+  if (cl->c.isC) {
+    int i;
+    for (i=0; i<cl->c.nupvalues; i++)  /* mark its upvalues */
+      markvalue(g, &cl->c.upvalue[i]);
+  }
+  else {
+    int i;
+    lua_assert(cl->l.nupvalues == cl->l.p->nups);
+    markobject(g, cl->l.p);
+    for (i=0; i<cl->l.nupvalues; i++)  /* mark its upvalues */
+      markobject(g, cl->l.upvals[i]);
+  }
+}
+
+
+static void checkstacksizes (lua_State *L, StkId max) {
+  int ci_used = cast_int(L->ci - L->base_ci);  /* number of `ci' in use */
+  int s_used = cast_int(max - L->stack);  /* part of stack in use */
+  if (L->size_ci > LUAI_MAXCALLS)  /* handling overflow? */
+    return;  /* do not touch the stacks */
+  if (4*ci_used < L->size_ci && 2*BASIC_CI_SIZE < L->size_ci)
+    luaD_reallocCI(L, L->size_ci/2);  /* still big enough... */
+  condhardstacktests(luaD_reallocCI(L, ci_used + 1));
+  if (4*s_used < L->stacksize &&
+      2*(BASIC_STACK_SIZE+EXTRA_STACK) < L->stacksize)
+    luaD_reallocstack(L, L->stacksize/2);  /* still big enough... */
+  condhardstacktests(luaD_reallocstack(L, s_used));
+}
+
+
+static void traversestack (global_State *g, lua_State *l) {
+  StkId o, lim;
+  CallInfo *ci;
+  markvalue(g, gt(l));
+  lim = l->top;
+  for (ci = l->base_ci; ci <= l->ci; ci++) {
+    lua_assert(ci->top <= l->stack_last);
+    if (lim < ci->top) lim = ci->top;
+  }
+  for (o = l->stack; o < l->top; o++)
+    markvalue(g, o);
+  for (; o <= lim; o++)
+    setnilvalue(o);
+  checkstacksizes(l, lim);
+}
+
+
+/*
+** traverse one gray object, turning it to black.
+** Returns `quantity' traversed.
+*/
+static l_mem propagatemark (global_State *g) {
+  GCObject *o = g->gray;
+  lua_assert(isgray(o));
+  gray2black(o);
+  switch (o->gch.tt) {
+    case LUA_TTABLE: {
+      Table *h = gco2h(o);
+      g->gray = h->gclist;
+      if (traversetable(g, h))  /* table is weak? */
+        black2gray(o);  /* keep it gray */
+      return sizeof(Table) + sizeof(TValue) * h->sizearray +
+                             sizeof(Node) * sizenode(h);
+    }
+    case LUA_TFUNCTION: {
+      Closure *cl = gco2cl(o);
+      g->gray = cl->c.gclist;
+      traverseclosure(g, cl);
+      return (cl->c.isC) ? sizeCclosure(cl->c.nupvalues) :
+                           sizeLclosure(cl->l.nupvalues);
+    }
+    case LUA_TTHREAD: {
+      lua_State *th = gco2th(o);
+      g->gray = th->gclist;
+      th->gclist = g->grayagain;
+      g->grayagain = o;
+      black2gray(o);
+      traversestack(g, th);
+      return sizeof(lua_State) + sizeof(TValue) * th->stacksize +
+                                 sizeof(CallInfo) * th->size_ci;
+    }
+    case LUA_TPROTO: {
+      Proto *p = gco2p(o);
+      g->gray = p->gclist;
+      traverseproto(g, p);
+      return sizeof(Proto) + sizeof(Instruction) * p->sizecode +
+                             sizeof(Proto *) * p->sizep +
+                             sizeof(TValue) * p->sizek + 
+                             sizeof(int) * p->sizelineinfo +
+                             sizeof(LocVar) * p->sizelocvars +
+                             sizeof(TString *) * p->sizeupvalues;
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+static size_t propagateall (global_State *g) {
+  size_t m = 0;
+  while (g->gray) m += propagatemark(g);
+  return m;
+}
+
+
+/*
+** The next function tells whether a key or value can be cleared from
+** a weak table. Non-collectable objects are never removed from weak
+** tables. Strings behave as `values', so are never removed too. for
+** other objects: if really collected, cannot keep them; for userdata
+** being finalized, keep them in keys, but not in values
+*/
+static int iscleared (const TValue *o, int iskey) {
+  if (!iscollectable(o)) return 0;
+  if (ttisstring(o)) {
+    stringmark(rawtsvalue(o));  /* strings are `values', so are never weak */
+    return 0;
+  }
+  return iswhite(gcvalue(o)) ||
+    (ttisuserdata(o) && (!iskey && isfinalized(uvalue(o))));
+}
+
+
+/*
+** clear collected entries from weaktables
+*/
+static void cleartable (GCObject *l) {
+  while (l) {
+    Table *h = gco2h(l);
+    int i = h->sizearray;
+    lua_assert(testbit(h->marked, VALUEWEAKBIT) ||
+               testbit(h->marked, KEYWEAKBIT));
+    if (testbit(h->marked, VALUEWEAKBIT)) {
+      while (i--) {
+        TValue *o = &h->array[i];
+        if (iscleared(o, 0))  /* value was collected? */
+          setnilvalue(o);  /* remove value */
+      }
+    }
+    i = sizenode(h);
+    while (i--) {
+      Node *n = gnode(h, i);
+      if (!ttisnil(gval(n)) &&  /* non-empty entry? */
+          (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) {
+        setnilvalue(gval(n));  /* remove value ... */
+        removeentry(n);  /* remove entry from table */
+      }
+    }
+    l = h->gclist;
+  }
+}
+
+
+static void freeobj (lua_State *L, GCObject *o) {
+  switch (o->gch.tt) {
+    case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break;
+    case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break;
+    case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break;
+    case LUA_TTABLE: luaH_free(L, gco2h(o)); break;
+    case LUA_TTHREAD: {
+      lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread);
+      luaE_freethread(L, gco2th(o));
+      break;
+    }
+    case LUA_TSTRING: {
+      G(L)->strt.nuse--;
+      luaM_freemem(L, o, sizestring(gco2ts(o)));
+      break;
+    }
+    case LUA_TUSERDATA: {
+      luaM_freemem(L, o, sizeudata(gco2u(o)));
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+
+#define sweepwholelist(L,p)	sweeplist(L,p,MAX_LUMEM)
+
+
+static GCObject **sweeplist (lua_State *L, GCObject **p, lu_mem count) {
+  GCObject *curr;
+  global_State *g = G(L);
+  int deadmask = otherwhite(g);
+  while ((curr = *p) != NULL && count-- > 0) {
+    if (curr->gch.tt == LUA_TTHREAD)  /* sweep open upvalues of each thread */
+      sweepwholelist(L, &gco2th(curr)->openupval);
+    if ((curr->gch.marked ^ WHITEBITS) & deadmask) {  /* not dead? */
+      lua_assert(!isdead(g, curr) || testbit(curr->gch.marked, FIXEDBIT));
+      makewhite(g, curr);  /* make it white (for next cycle) */
+      p = &curr->gch.next;
+    }
+    else {  /* must erase `curr' */
+      lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT));
+      *p = curr->gch.next;
+      if (curr == g->rootgc)  /* is the first element of the list? */
+        g->rootgc = curr->gch.next;  /* adjust first */
+      freeobj(L, curr);
+    }
+  }
+  return p;
+}
+
+
+static void checkSizes (lua_State *L) {
+  global_State *g = G(L);
+  /* check size of string hash */
+  if (g->strt.nuse < cast(lu_int32, g->strt.size/4) &&
+      g->strt.size > MINSTRTABSIZE*2)
+    luaS_resize(L, g->strt.size/2);  /* table is too big */
+  /* check size of buffer */
+  if (luaZ_sizebuffer(&g->buff) > LUA_MINBUFFER*2) {  /* buffer too big? */
+    size_t newsize = luaZ_sizebuffer(&g->buff) / 2;
+    luaZ_resizebuffer(L, &g->buff, newsize);
+  }
+}
+
+
+static void GCTM (lua_State *L) {
+  global_State *g = G(L);
+  GCObject *o = g->tmudata->gch.next;  /* get first element */
+  Udata *udata = rawgco2u(o);
+  const TValue *tm;
+  /* remove udata from `tmudata' */
+  if (o == g->tmudata)  /* last element? */
+    g->tmudata = NULL;
+  else
+    g->tmudata->gch.next = udata->uv.next;
+  udata->uv.next = g->mainthread->next;  /* return it to `root' list */
+  g->mainthread->next = o;
+  makewhite(g, o);
+  tm = fasttm(L, udata->uv.metatable, TM_GC);
+  if (tm != NULL) {
+    lu_byte oldah = L->allowhook;
+    lu_mem oldt = g->GCthreshold;
+    L->allowhook = 0;  /* stop debug hooks during GC tag method */
+    g->GCthreshold = 2*g->totalbytes;  /* avoid GC steps */
+    setobj2s(L, L->top, tm);
+    setuvalue(L, L->top+1, udata);
+    L->top += 2;
+    luaD_call(L, L->top - 2, 0);
+    L->allowhook = oldah;  /* restore hooks */
+    g->GCthreshold = oldt;  /* restore threshold */
+  }
+}
+
+
+/*
+** Call all GC tag methods
+*/
+void luaC_callGCTM (lua_State *L) {
+  while (G(L)->tmudata)
+    GCTM(L);
+}
+
+
+void luaC_freeall (lua_State *L) {
+  global_State *g = G(L);
+  int i;
+  g->currentwhite = WHITEBITS | bitmask(SFIXEDBIT);  /* mask to collect all elements */
+  sweepwholelist(L, &g->rootgc);
+  for (i = 0; i < g->strt.size; i++)  /* free all string lists */
+    sweepwholelist(L, &g->strt.hash[i]);
+}
+
+
+static void markmt (global_State *g) {
+  int i;
+  for (i=0; i<NUM_TAGS; i++)
+    if (g->mt[i]) markobject(g, g->mt[i]);
+}
+
+
+/* mark root set */
+static void markroot (lua_State *L) {
+  global_State *g = G(L);
+  g->gray = NULL;
+  g->grayagain = NULL;
+  g->weak = NULL;
+  markobject(g, g->mainthread);
+  /* make global table be traversed before main stack */
+  markvalue(g, gt(g->mainthread));
+  markvalue(g, registry(L));
+  markmt(g);
+  g->gcstate = GCSpropagate;
+}
+
+
+static void remarkupvals (global_State *g) {
+  UpVal *uv;
+  for (uv = g->uvhead.u.l.next; uv != &g->uvhead; uv = uv->u.l.next) {
+    lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
+    if (isgray(obj2gco(uv)))
+      markvalue(g, uv->v);
+  }
+}
+
+
+static void atomic (lua_State *L) {
+  global_State *g = G(L);
+  size_t udsize;  /* total size of userdata to be finalized */
+  /* remark occasional upvalues of (maybe) dead threads */
+  remarkupvals(g);
+  /* traverse objects cautch by write barrier and by 'remarkupvals' */
+  propagateall(g);
+  /* remark weak tables */
+  g->gray = g->weak;
+  g->weak = NULL;
+  lua_assert(!iswhite(obj2gco(g->mainthread)));
+  markobject(g, L);  /* mark running thread */
+  markmt(g);  /* mark basic metatables (again) */
+  propagateall(g);
+  /* remark gray again */
+  g->gray = g->grayagain;
+  g->grayagain = NULL;
+  propagateall(g);
+  udsize = luaC_separateudata(L, 0);  /* separate userdata to be finalized */
+  marktmu(g);  /* mark `preserved' userdata */
+  udsize += propagateall(g);  /* remark, to propagate `preserveness' */
+  cleartable(g->weak);  /* remove collected objects from weak tables */
+  /* flip current white */
+  g->currentwhite = cast_byte(otherwhite(g));
+  g->sweepstrgc = 0;
+  g->sweepgc = &g->rootgc;
+  g->gcstate = GCSsweepstring;
+  g->estimate = g->totalbytes - udsize;  /* first estimate */
+}
+
+
+static l_mem singlestep (lua_State *L) {
+  global_State *g = G(L);
+  /*lua_checkmemory(L);*/
+  switch (g->gcstate) {
+    case GCSpause: {
+      markroot(L);  /* start a new collection */
+      return 0;
+    }
+    case GCSpropagate: {
+      if (g->gray)
+        return propagatemark(g);
+      else {  /* no more `gray' objects */
+        atomic(L);  /* finish mark phase */
+        return 0;
+      }
+    }
+    case GCSsweepstring: {
+      lu_mem old = g->totalbytes;
+      sweepwholelist(L, &g->strt.hash[g->sweepstrgc++]);
+      if (g->sweepstrgc >= g->strt.size)  /* nothing more to sweep? */
+        g->gcstate = GCSsweep;  /* end sweep-string phase */
+      lua_assert(old >= g->totalbytes);
+      g->estimate -= old - g->totalbytes;
+      return GCSWEEPCOST;
+    }
+    case GCSsweep: {
+      lu_mem old = g->totalbytes;
+      g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX);
+      if (*g->sweepgc == NULL) {  /* nothing more to sweep? */
+        checkSizes(L);
+        g->gcstate = GCSfinalize;  /* end sweep phase */
+      }
+      lua_assert(old >= g->totalbytes);
+      g->estimate -= old - g->totalbytes;
+      return GCSWEEPMAX*GCSWEEPCOST;
+    }
+    case GCSfinalize: {
+      if (g->tmudata) {
+        GCTM(L);
+        if (g->estimate > GCFINALIZECOST)
+          g->estimate -= GCFINALIZECOST;
+        return GCFINALIZECOST;
+      }
+      else {
+        g->gcstate = GCSpause;  /* end collection */
+        g->gcdept = 0;
+        return 0;
+      }
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+void luaC_step (lua_State *L) {
+  global_State *g = G(L);
+  l_mem lim = (GCSTEPSIZE/100) * g->gcstepmul;
+  if (lim == 0)
+    lim = (MAX_LUMEM-1)/2;  /* no limit */
+  g->gcdept += g->totalbytes - g->GCthreshold;
+  do {
+    lim -= singlestep(L);
+    if (g->gcstate == GCSpause)
+      break;
+  } while (lim > 0);
+  if (g->gcstate != GCSpause) {
+    if (g->gcdept < GCSTEPSIZE)
+      g->GCthreshold = g->totalbytes + GCSTEPSIZE;  /* - lim/g->gcstepmul;*/
+    else {
+      g->gcdept -= GCSTEPSIZE;
+      g->GCthreshold = g->totalbytes;
+    }
+  }
+  else {
+    setthreshold(g);
+  }
+}
+
+
+void luaC_fullgc (lua_State *L) {
+  global_State *g = G(L);
+  if (g->gcstate <= GCSpropagate) {
+    /* reset sweep marks to sweep all elements (returning them to white) */
+    g->sweepstrgc = 0;
+    g->sweepgc = &g->rootgc;
+    /* reset other collector lists */
+    g->gray = NULL;
+    g->grayagain = NULL;
+    g->weak = NULL;
+    g->gcstate = GCSsweepstring;
+  }
+  lua_assert(g->gcstate != GCSpause && g->gcstate != GCSpropagate);
+  /* finish any pending sweep phase */
+  while (g->gcstate != GCSfinalize) {
+    lua_assert(g->gcstate == GCSsweepstring || g->gcstate == GCSsweep);
+    singlestep(L);
+  }
+  markroot(L);
+  while (g->gcstate != GCSpause) {
+    singlestep(L);
+  }
+  setthreshold(g);
+}
+
+
+void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v) {
+  global_State *g = G(L);
+  lua_assert(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o));
+  lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
+  lua_assert(ttype(&o->gch) != LUA_TTABLE);
+  /* must keep invariant? */
+  if (g->gcstate == GCSpropagate)
+    reallymarkobject(g, v);  /* restore invariant */
+  else  /* don't mind */
+    makewhite(g, o);  /* mark as white just to avoid other barriers */
+}
+
+
+void luaC_barrierback (lua_State *L, Table *t) {
+  global_State *g = G(L);
+  GCObject *o = obj2gco(t);
+  lua_assert(isblack(o) && !isdead(g, o));
+  lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
+  black2gray(o);  /* make table gray (again) */
+  t->gclist = g->grayagain;
+  g->grayagain = o;
+}
+
+
+void luaC_link (lua_State *L, GCObject *o, lu_byte tt) {
+  global_State *g = G(L);
+  o->gch.next = g->rootgc;
+  g->rootgc = o;
+  o->gch.marked = luaC_white(g);
+  o->gch.tt = tt;
+}
+
+
+void luaC_linkupval (lua_State *L, UpVal *uv) {
+  global_State *g = G(L);
+  GCObject *o = obj2gco(uv);
+  o->gch.next = g->rootgc;  /* link upvalue into `rootgc' list */
+  g->rootgc = o;
+  if (isgray(o)) { 
+    if (g->gcstate == GCSpropagate) {
+      gray2black(o);  /* closed upvalues need barrier */
+      luaC_barrier(L, uv, uv->v);
+    }
+    else {  /* sweep phase: sweep it (turning it into white) */
+      makewhite(g, o);
+      lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
+    }
+  }
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lgc.h b/third_party/lua-src/lua-5.1.5/lgc.h
new file mode 100644
index 00000000..5a8dc605
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lgc.h
@@ -0,0 +1,110 @@
+/*
+** $Id: lgc.h,v 2.15.1.1 2007/12/27 13:02:25 roberto Exp $
+** Garbage Collector
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lgc_h
+#define lgc_h
+
+
+#include "lobject.h"
+
+
+/*
+** Possible states of the Garbage Collector
+*/
+#define GCSpause	0
+#define GCSpropagate	1
+#define GCSsweepstring	2
+#define GCSsweep	3
+#define GCSfinalize	4
+
+
+/*
+** some userful bit tricks
+*/
+#define resetbits(x,m)	((x) &= cast(lu_byte, ~(m)))
+#define setbits(x,m)	((x) |= (m))
+#define testbits(x,m)	((x) & (m))
+#define bitmask(b)	(1<<(b))
+#define bit2mask(b1,b2)	(bitmask(b1) | bitmask(b2))
+#define l_setbit(x,b)	setbits(x, bitmask(b))
+#define resetbit(x,b)	resetbits(x, bitmask(b))
+#define testbit(x,b)	testbits(x, bitmask(b))
+#define set2bits(x,b1,b2)	setbits(x, (bit2mask(b1, b2)))
+#define reset2bits(x,b1,b2)	resetbits(x, (bit2mask(b1, b2)))
+#define test2bits(x,b1,b2)	testbits(x, (bit2mask(b1, b2)))
+
+
+
+/*
+** Layout for bit use in `marked' field:
+** bit 0 - object is white (type 0)
+** bit 1 - object is white (type 1)
+** bit 2 - object is black
+** bit 3 - for userdata: has been finalized
+** bit 3 - for tables: has weak keys
+** bit 4 - for tables: has weak values
+** bit 5 - object is fixed (should not be collected)
+** bit 6 - object is "super" fixed (only the main thread)
+*/
+
+
+#define WHITE0BIT	0
+#define WHITE1BIT	1
+#define BLACKBIT	2
+#define FINALIZEDBIT	3
+#define KEYWEAKBIT	3
+#define VALUEWEAKBIT	4
+#define FIXEDBIT	5
+#define SFIXEDBIT	6
+#define WHITEBITS	bit2mask(WHITE0BIT, WHITE1BIT)
+
+
+#define iswhite(x)      test2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT)
+#define isblack(x)      testbit((x)->gch.marked, BLACKBIT)
+#define isgray(x)	(!isblack(x) && !iswhite(x))
+
+#define otherwhite(g)	(g->currentwhite ^ WHITEBITS)
+#define isdead(g,v)	((v)->gch.marked & otherwhite(g) & WHITEBITS)
+
+#define changewhite(x)	((x)->gch.marked ^= WHITEBITS)
+#define gray2black(x)	l_setbit((x)->gch.marked, BLACKBIT)
+
+#define valiswhite(x)	(iscollectable(x) && iswhite(gcvalue(x)))
+
+#define luaC_white(g)	cast(lu_byte, (g)->currentwhite & WHITEBITS)
+
+
+#define luaC_checkGC(L) { \
+  condhardstacktests(luaD_reallocstack(L, L->stacksize - EXTRA_STACK - 1)); \
+  if (G(L)->totalbytes >= G(L)->GCthreshold) \
+	luaC_step(L); }
+
+
+#define luaC_barrier(L,p,v) { if (valiswhite(v) && isblack(obj2gco(p)))  \
+	luaC_barrierf(L,obj2gco(p),gcvalue(v)); }
+
+#define luaC_barriert(L,t,v) { if (valiswhite(v) && isblack(obj2gco(t)))  \
+	luaC_barrierback(L,t); }
+
+#define luaC_objbarrier(L,p,o)  \
+	{ if (iswhite(obj2gco(o)) && isblack(obj2gco(p))) \
+		luaC_barrierf(L,obj2gco(p),obj2gco(o)); }
+
+#define luaC_objbarriert(L,t,o)  \
+   { if (iswhite(obj2gco(o)) && isblack(obj2gco(t))) luaC_barrierback(L,t); }
+
+LUAI_FUNC size_t luaC_separateudata (lua_State *L, int all);
+LUAI_FUNC void luaC_callGCTM (lua_State *L);
+LUAI_FUNC void luaC_freeall (lua_State *L);
+LUAI_FUNC void luaC_step (lua_State *L);
+LUAI_FUNC void luaC_fullgc (lua_State *L);
+LUAI_FUNC void luaC_link (lua_State *L, GCObject *o, lu_byte tt);
+LUAI_FUNC void luaC_linkupval (lua_State *L, UpVal *uv);
+LUAI_FUNC void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v);
+LUAI_FUNC void luaC_barrierback (lua_State *L, Table *t);
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/linit.c b/third_party/lua-src/lua-5.1.5/linit.c
new file mode 100644
index 00000000..c1f90dfa
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/linit.c
@@ -0,0 +1,38 @@
+/*
+** $Id: linit.c,v 1.14.1.1 2007/12/27 13:02:25 roberto Exp $
+** Initialization of libraries for lua.c
+** See Copyright Notice in lua.h
+*/
+
+
+#define linit_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lualib.h"
+#include "lauxlib.h"
+
+
+static const luaL_Reg lualibs[] = {
+  {"", luaopen_base},
+  {LUA_LOADLIBNAME, luaopen_package},
+  {LUA_TABLIBNAME, luaopen_table},
+  {LUA_IOLIBNAME, luaopen_io},
+  {LUA_OSLIBNAME, luaopen_os},
+  {LUA_STRLIBNAME, luaopen_string},
+  {LUA_MATHLIBNAME, luaopen_math},
+  {LUA_DBLIBNAME, luaopen_debug},
+  {NULL, NULL}
+};
+
+
+LUALIB_API void luaL_openlibs (lua_State *L) {
+  const luaL_Reg *lib = lualibs;
+  for (; lib->func; lib++) {
+    lua_pushcfunction(L, lib->func);
+    lua_pushstring(L, lib->name);
+    lua_call(L, 1, 0);
+  }
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/liolib.c b/third_party/lua-src/lua-5.1.5/liolib.c
new file mode 100644
index 00000000..65327afe
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/liolib.c
@@ -0,0 +1,560 @@
+/*
+** $Id: liolib.c,v 2.73.1.4 2010/05/14 15:33:51 roberto Exp $
+** Standard I/O (and system) library
+** See Copyright Notice in lua.h
+*/
+
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define liolib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+#define IO_INPUT	1
+#define IO_OUTPUT	2
+
+
+static const char *const fnames[] = {"input", "output"};
+
+
+static int pushresult (lua_State *L, int i, const char *filename) {
+  int en = errno;  /* calls to Lua API may change this value */
+  if (i) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);
+    if (filename)
+      lua_pushfstring(L, "%s: %s", filename, strerror(en));
+    else
+      lua_pushfstring(L, "%s", strerror(en));
+    lua_pushinteger(L, en);
+    return 3;
+  }
+}
+
+
+static void fileerror (lua_State *L, int arg, const char *filename) {
+  lua_pushfstring(L, "%s: %s", filename, strerror(errno));
+  luaL_argerror(L, arg, lua_tostring(L, -1));
+}
+
+
+#define tofilep(L)	((FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE))
+
+
+static int io_type (lua_State *L) {
+  void *ud;
+  luaL_checkany(L, 1);
+  ud = lua_touserdata(L, 1);
+  lua_getfield(L, LUA_REGISTRYINDEX, LUA_FILEHANDLE);
+  if (ud == NULL || !lua_getmetatable(L, 1) || !lua_rawequal(L, -2, -1))
+    lua_pushnil(L);  /* not a file */
+  else if (*((FILE **)ud) == NULL)
+    lua_pushliteral(L, "closed file");
+  else
+    lua_pushliteral(L, "file");
+  return 1;
+}
+
+
+static FILE *tofile (lua_State *L) {
+  FILE **f = tofilep(L);
+  if (*f == NULL)
+    luaL_error(L, "attempt to use a closed file");
+  return *f;
+}
+
+
+
+/*
+** When creating file handles, always creates a `closed' file handle
+** before opening the actual file; so, if there is a memory error, the
+** file is not left opened.
+*/
+static FILE **newfile (lua_State *L) {
+  FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
+  *pf = NULL;  /* file handle is currently `closed' */
+  luaL_getmetatable(L, LUA_FILEHANDLE);
+  lua_setmetatable(L, -2);
+  return pf;
+}
+
+
+/*
+** function to (not) close the standard files stdin, stdout, and stderr
+*/
+static int io_noclose (lua_State *L) {
+  lua_pushnil(L);
+  lua_pushliteral(L, "cannot close standard file");
+  return 2;
+}
+
+
+/*
+** function to close 'popen' files
+*/
+static int io_pclose (lua_State *L) {
+  FILE **p = tofilep(L);
+  int ok = lua_pclose(L, *p);
+  *p = NULL;
+  return pushresult(L, ok, NULL);
+}
+
+
+/*
+** function to close regular files
+*/
+static int io_fclose (lua_State *L) {
+  FILE **p = tofilep(L);
+  int ok = (fclose(*p) == 0);
+  *p = NULL;
+  return pushresult(L, ok, NULL);
+}
+
+
+static int aux_close (lua_State *L) {
+  lua_getfenv(L, 1);
+  lua_getfield(L, -1, "__close");
+  return (lua_tocfunction(L, -1))(L);
+}
+
+
+static int io_close (lua_State *L) {
+  if (lua_isnone(L, 1))
+    lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
+  tofile(L);  /* make sure argument is a file */
+  return aux_close(L);
+}
+
+
+static int io_gc (lua_State *L) {
+  FILE *f = *tofilep(L);
+  /* ignore closed files */
+  if (f != NULL)
+    aux_close(L);
+  return 0;
+}
+
+
+static int io_tostring (lua_State *L) {
+  FILE *f = *tofilep(L);
+  if (f == NULL)
+    lua_pushliteral(L, "file (closed)");
+  else
+    lua_pushfstring(L, "file (%p)", f);
+  return 1;
+}
+
+
+static int io_open (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  const char *mode = luaL_optstring(L, 2, "r");
+  FILE **pf = newfile(L);
+  *pf = fopen(filename, mode);
+  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+}
+
+
+/*
+** this function has a separated environment, which defines the
+** correct __close for 'popen' files
+*/
+static int io_popen (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  const char *mode = luaL_optstring(L, 2, "r");
+  FILE **pf = newfile(L);
+  *pf = lua_popen(L, filename, mode);
+  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+}
+
+
+static int io_tmpfile (lua_State *L) {
+#if !defined(__wasi__)
+  FILE **pf = newfile(L);
+  *pf = tmpfile();
+  return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
+#else
+  luaL_error(L, "not supported on WASI");
+#endif
+}
+
+
+static FILE *getiofile (lua_State *L, int findex) {
+  FILE *f;
+  lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
+  f = *(FILE **)lua_touserdata(L, -1);
+  if (f == NULL)
+    luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
+  return f;
+}
+
+
+static int g_iofile (lua_State *L, int f, const char *mode) {
+  if (!lua_isnoneornil(L, 1)) {
+    const char *filename = lua_tostring(L, 1);
+    if (filename) {
+      FILE **pf = newfile(L);
+      *pf = fopen(filename, mode);
+      if (*pf == NULL)
+        fileerror(L, 1, filename);
+    }
+    else {
+      tofile(L);  /* check that it's a valid file handle */
+      lua_pushvalue(L, 1);
+    }
+    lua_rawseti(L, LUA_ENVIRONINDEX, f);
+  }
+  /* return current value */
+  lua_rawgeti(L, LUA_ENVIRONINDEX, f);
+  return 1;
+}
+
+
+static int io_input (lua_State *L) {
+  return g_iofile(L, IO_INPUT, "r");
+}
+
+
+static int io_output (lua_State *L) {
+  return g_iofile(L, IO_OUTPUT, "w");
+}
+
+
+static int io_readline (lua_State *L);
+
+
+static void aux_lines (lua_State *L, int idx, int toclose) {
+  lua_pushvalue(L, idx);
+  lua_pushboolean(L, toclose);  /* close/not close file when finished */
+  lua_pushcclosure(L, io_readline, 2);
+}
+
+
+static int f_lines (lua_State *L) {
+  tofile(L);  /* check that it's a valid file handle */
+  aux_lines(L, 1, 0);
+  return 1;
+}
+
+
+static int io_lines (lua_State *L) {
+  if (lua_isnoneornil(L, 1)) {  /* no arguments? */
+    /* will iterate over default input */
+    lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT);
+    return f_lines(L);
+  }
+  else {
+    const char *filename = luaL_checkstring(L, 1);
+    FILE **pf = newfile(L);
+    *pf = fopen(filename, "r");
+    if (*pf == NULL)
+      fileerror(L, 1, filename);
+    aux_lines(L, lua_gettop(L), 1);
+    return 1;
+  }
+}
+
+
+/*
+** {======================================================
+** READ
+** =======================================================
+*/
+
+
+static int read_number (lua_State *L, FILE *f) {
+  lua_Number d;
+  if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
+    lua_pushnumber(L, d);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);  /* "result" to be removed */
+    return 0;  /* read fails */
+  }
+}
+
+
+static int test_eof (lua_State *L, FILE *f) {
+  int c = getc(f);
+  ungetc(c, f);
+  lua_pushlstring(L, NULL, 0);
+  return (c != EOF);
+}
+
+
+static int read_line (lua_State *L, FILE *f) {
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  for (;;) {
+    size_t l;
+    char *p = luaL_prepbuffer(&b);
+    if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) {  /* eof? */
+      luaL_pushresult(&b);  /* close buffer */
+      return (lua_objlen(L, -1) > 0);  /* check whether read something */
+    }
+    l = strlen(p);
+    if (l == 0 || p[l-1] != '\n')
+      luaL_addsize(&b, l);
+    else {
+      luaL_addsize(&b, l - 1);  /* do not include `eol' */
+      luaL_pushresult(&b);  /* close buffer */
+      return 1;  /* read at least an `eol' */
+    }
+  }
+}
+
+
+static int read_chars (lua_State *L, FILE *f, size_t n) {
+  size_t rlen;  /* how much to read */
+  size_t nr;  /* number of chars actually read */
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  rlen = LUAL_BUFFERSIZE;  /* try to read that much each time */
+  do {
+    char *p = luaL_prepbuffer(&b);
+    if (rlen > n) rlen = n;  /* cannot read more than asked */
+    nr = fread(p, sizeof(char), rlen, f);
+    luaL_addsize(&b, nr);
+    n -= nr;  /* still have to read `n' chars */
+  } while (n > 0 && nr == rlen);  /* until end of count or eof */
+  luaL_pushresult(&b);  /* close buffer */
+  return (n == 0 || lua_objlen(L, -1) > 0);
+}
+
+
+static int g_read (lua_State *L, FILE *f, int first) {
+  int nargs = lua_gettop(L) - 1;
+  int success;
+  int n;
+  clearerr(f);
+  if (nargs == 0) {  /* no arguments? */
+    success = read_line(L, f);
+    n = first+1;  /* to return 1 result */
+  }
+  else {  /* ensure stack space for all results and for auxlib's buffer */
+    luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
+    success = 1;
+    for (n = first; nargs-- && success; n++) {
+      if (lua_type(L, n) == LUA_TNUMBER) {
+        size_t l = (size_t)lua_tointeger(L, n);
+        success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
+      }
+      else {
+        const char *p = lua_tostring(L, n);
+        luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
+        switch (p[1]) {
+          case 'n':  /* number */
+            success = read_number(L, f);
+            break;
+          case 'l':  /* line */
+            success = read_line(L, f);
+            break;
+          case 'a':  /* file */
+            read_chars(L, f, ~((size_t)0));  /* read MAX_SIZE_T chars */
+            success = 1; /* always success */
+            break;
+          default:
+            return luaL_argerror(L, n, "invalid format");
+        }
+      }
+    }
+  }
+  if (ferror(f))
+    return pushresult(L, 0, NULL);
+  if (!success) {
+    lua_pop(L, 1);  /* remove last result */
+    lua_pushnil(L);  /* push nil instead */
+  }
+  return n - first;
+}
+
+
+static int io_read (lua_State *L) {
+  return g_read(L, getiofile(L, IO_INPUT), 1);
+}
+
+
+static int f_read (lua_State *L) {
+  return g_read(L, tofile(L), 2);
+}
+
+
+static int io_readline (lua_State *L) {
+  FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1));
+  int sucess;
+  if (f == NULL)  /* file is already closed? */
+    luaL_error(L, "file is already closed");
+  sucess = read_line(L, f);
+  if (ferror(f))
+    return luaL_error(L, "%s", strerror(errno));
+  if (sucess) return 1;
+  else {  /* EOF */
+    if (lua_toboolean(L, lua_upvalueindex(2))) {  /* generator created file? */
+      lua_settop(L, 0);
+      lua_pushvalue(L, lua_upvalueindex(1));
+      aux_close(L);  /* close it */
+    }
+    return 0;
+  }
+}
+
+/* }====================================================== */
+
+
+static int g_write (lua_State *L, FILE *f, int arg) {
+  int nargs = lua_gettop(L) - 1;
+  int status = 1;
+  for (; nargs--; arg++) {
+    if (lua_type(L, arg) == LUA_TNUMBER) {
+      /* optimization: could be done exactly as for strings */
+      status = status &&
+          fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
+    }
+    else {
+      size_t l;
+      const char *s = luaL_checklstring(L, arg, &l);
+      status = status && (fwrite(s, sizeof(char), l, f) == l);
+    }
+  }
+  return pushresult(L, status, NULL);
+}
+
+
+static int io_write (lua_State *L) {
+  return g_write(L, getiofile(L, IO_OUTPUT), 1);
+}
+
+
+static int f_write (lua_State *L) {
+  return g_write(L, tofile(L), 2);
+}
+
+
+static int f_seek (lua_State *L) {
+  static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
+  static const char *const modenames[] = {"set", "cur", "end", NULL};
+  FILE *f = tofile(L);
+  int op = luaL_checkoption(L, 2, "cur", modenames);
+  long offset = luaL_optlong(L, 3, 0);
+  op = fseek(f, offset, mode[op]);
+  if (op)
+    return pushresult(L, 0, NULL);  /* error */
+  else {
+    lua_pushinteger(L, ftell(f));
+    return 1;
+  }
+}
+
+
+static int f_setvbuf (lua_State *L) {
+  static const int mode[] = {_IONBF, _IOFBF, _IOLBF};
+  static const char *const modenames[] = {"no", "full", "line", NULL};
+  FILE *f = tofile(L);
+  int op = luaL_checkoption(L, 2, NULL, modenames);
+  lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
+  int res = setvbuf(f, NULL, mode[op], sz);
+  return pushresult(L, res == 0, NULL);
+}
+
+
+
+static int io_flush (lua_State *L) {
+  return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
+}
+
+
+static int f_flush (lua_State *L) {
+  return pushresult(L, fflush(tofile(L)) == 0, NULL);
+}
+
+
+static const luaL_Reg iolib[] = {
+  {"close", io_close},
+  {"flush", io_flush},
+  {"input", io_input},
+  {"lines", io_lines},
+  {"open", io_open},
+  {"output", io_output},
+  {"popen", io_popen},
+  {"read", io_read},
+  {"tmpfile", io_tmpfile},
+  {"type", io_type},
+  {"write", io_write},
+  {NULL, NULL}
+};
+
+
+static const luaL_Reg flib[] = {
+  {"close", io_close},
+  {"flush", f_flush},
+  {"lines", f_lines},
+  {"read", f_read},
+  {"seek", f_seek},
+  {"setvbuf", f_setvbuf},
+  {"write", f_write},
+  {"__gc", io_gc},
+  {"__tostring", io_tostring},
+  {NULL, NULL}
+};
+
+
+static void createmeta (lua_State *L) {
+  luaL_newmetatable(L, LUA_FILEHANDLE);  /* create metatable for file handles */
+  lua_pushvalue(L, -1);  /* push metatable */
+  lua_setfield(L, -2, "__index");  /* metatable.__index = metatable */
+  luaL_register(L, NULL, flib);  /* file methods */
+}
+
+
+static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) {
+  *newfile(L) = f;
+  if (k > 0) {
+    lua_pushvalue(L, -1);
+    lua_rawseti(L, LUA_ENVIRONINDEX, k);
+  }
+  lua_pushvalue(L, -2);  /* copy environment */
+  lua_setfenv(L, -2);  /* set it */
+  lua_setfield(L, -3, fname);
+}
+
+
+static void newfenv (lua_State *L, lua_CFunction cls) {
+  lua_createtable(L, 0, 1);
+  lua_pushcfunction(L, cls);
+  lua_setfield(L, -2, "__close");
+}
+
+
+LUALIB_API int luaopen_io (lua_State *L) {
+  createmeta(L);
+  /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
+  newfenv(L, io_fclose);
+  lua_replace(L, LUA_ENVIRONINDEX);
+  /* open library */
+  luaL_register(L, LUA_IOLIBNAME, iolib);
+  /* create (and set) default files */
+  newfenv(L, io_noclose);  /* close function for default files */
+  createstdfile(L, stdin, IO_INPUT, "stdin");
+  createstdfile(L, stdout, IO_OUTPUT, "stdout");
+  createstdfile(L, stderr, 0, "stderr");
+  lua_pop(L, 1);  /* pop environment for default files */
+  lua_getfield(L, -1, "popen");
+  newfenv(L, io_pclose);  /* create environment for 'popen' */
+  lua_setfenv(L, -2);  /* set fenv for 'popen' */
+  lua_pop(L, 1);  /* pop 'popen' */
+  return 1;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/llex.c b/third_party/lua-src/lua-5.1.5/llex.c
new file mode 100644
index 00000000..88c6790c
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/llex.c
@@ -0,0 +1,463 @@
+/*
+** $Id: llex.c,v 2.20.1.2 2009/11/23 14:58:22 roberto Exp $
+** Lexical Analyzer
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <locale.h>
+#include <string.h>
+
+#define llex_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldo.h"
+#include "llex.h"
+#include "lobject.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lzio.h"
+
+
+
+#define next(ls) (ls->current = zgetc(ls->z))
+
+
+
+
+#define currIsNewline(ls)	(ls->current == '\n' || ls->current == '\r')
+
+
+/* ORDER RESERVED */
+const char *const luaX_tokens [] = {
+    "and", "break", "do", "else", "elseif",
+    "end", "false", "for", "function", "if",
+    "in", "local", "nil", "not", "or", "repeat",
+    "return", "then", "true", "until", "while",
+    "..", "...", "==", ">=", "<=", "~=",
+    "<number>", "<name>", "<string>", "<eof>",
+    NULL
+};
+
+
+#define save_and_next(ls) (save(ls, ls->current), next(ls))
+
+
+static void save (LexState *ls, int c) {
+  Mbuffer *b = ls->buff;
+  if (b->n + 1 > b->buffsize) {
+    size_t newsize;
+    if (b->buffsize >= MAX_SIZET/2)
+      luaX_lexerror(ls, "lexical element too long", 0);
+    newsize = b->buffsize * 2;
+    luaZ_resizebuffer(ls->L, b, newsize);
+  }
+  b->buffer[b->n++] = cast(char, c);
+}
+
+
+void luaX_init (lua_State *L) {
+  int i;
+  for (i=0; i<NUM_RESERVED; i++) {
+    TString *ts = luaS_new(L, luaX_tokens[i]);
+    luaS_fix(ts);  /* reserved words are never collected */
+    lua_assert(strlen(luaX_tokens[i])+1 <= TOKEN_LEN);
+    ts->tsv.reserved = cast_byte(i+1);  /* reserved word */
+  }
+}
+
+
+#define MAXSRC          80
+
+
+const char *luaX_token2str (LexState *ls, int token) {
+  if (token < FIRST_RESERVED) {
+    lua_assert(token == cast(unsigned char, token));
+    return (iscntrl(token)) ? luaO_pushfstring(ls->L, "char(%d)", token) :
+                              luaO_pushfstring(ls->L, "%c", token);
+  }
+  else
+    return luaX_tokens[token-FIRST_RESERVED];
+}
+
+
+static const char *txtToken (LexState *ls, int token) {
+  switch (token) {
+    case TK_NAME:
+    case TK_STRING:
+    case TK_NUMBER:
+      save(ls, '\0');
+      return luaZ_buffer(ls->buff);
+    default:
+      return luaX_token2str(ls, token);
+  }
+}
+
+
+void luaX_lexerror (LexState *ls, const char *msg, int token) {
+  char buff[MAXSRC];
+  luaO_chunkid(buff, getstr(ls->source), MAXSRC);
+  msg = luaO_pushfstring(ls->L, "%s:%d: %s", buff, ls->linenumber, msg);
+  if (token)
+    luaO_pushfstring(ls->L, "%s near " LUA_QS, msg, txtToken(ls, token));
+  luaD_throw(ls->L, LUA_ERRSYNTAX);
+}
+
+
+void luaX_syntaxerror (LexState *ls, const char *msg) {
+  luaX_lexerror(ls, msg, ls->t.token);
+}
+
+
+TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
+  lua_State *L = ls->L;
+  TString *ts = luaS_newlstr(L, str, l);
+  TValue *o = luaH_setstr(L, ls->fs->h, ts);  /* entry for `str' */
+  if (ttisnil(o)) {
+    setbvalue(o, 1);  /* make sure `str' will not be collected */
+    luaC_checkGC(L);
+  }
+  return ts;
+}
+
+
+static void inclinenumber (LexState *ls) {
+  int old = ls->current;
+  lua_assert(currIsNewline(ls));
+  next(ls);  /* skip `\n' or `\r' */
+  if (currIsNewline(ls) && ls->current != old)
+    next(ls);  /* skip `\n\r' or `\r\n' */
+  if (++ls->linenumber >= MAX_INT)
+    luaX_syntaxerror(ls, "chunk has too many lines");
+}
+
+
+void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source) {
+  ls->decpoint = '.';
+  ls->L = L;
+  ls->lookahead.token = TK_EOS;  /* no look-ahead token */
+  ls->z = z;
+  ls->fs = NULL;
+  ls->linenumber = 1;
+  ls->lastline = 1;
+  ls->source = source;
+  luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER);  /* initialize buffer */
+  next(ls);  /* read first char */
+}
+
+
+
+/*
+** =======================================================
+** LEXICAL ANALYZER
+** =======================================================
+*/
+
+
+
+static int check_next (LexState *ls, const char *set) {
+  if (!strchr(set, ls->current))
+    return 0;
+  save_and_next(ls);
+  return 1;
+}
+
+
+static void buffreplace (LexState *ls, char from, char to) {
+  size_t n = luaZ_bufflen(ls->buff);
+  char *p = luaZ_buffer(ls->buff);
+  while (n--)
+    if (p[n] == from) p[n] = to;
+}
+
+
+static void trydecpoint (LexState *ls, SemInfo *seminfo) {
+  /* format error: try to update decimal point separator */
+  struct lconv *cv = localeconv();
+  char old = ls->decpoint;
+  ls->decpoint = (cv ? cv->decimal_point[0] : '.');
+  buffreplace(ls, old, ls->decpoint);  /* try updated decimal separator */
+  if (!luaO_str2d(luaZ_buffer(ls->buff), &seminfo->r)) {
+    /* format error with correct decimal point: no more options */
+    buffreplace(ls, ls->decpoint, '.');  /* undo change (for error message) */
+    luaX_lexerror(ls, "malformed number", TK_NUMBER);
+  }
+}
+
+
+/* LUA_NUMBER */
+static void read_numeral (LexState *ls, SemInfo *seminfo) {
+  lua_assert(isdigit(ls->current));
+  do {
+    save_and_next(ls);
+  } while (isdigit(ls->current) || ls->current == '.');
+  if (check_next(ls, "Ee"))  /* `E'? */
+    check_next(ls, "+-");  /* optional exponent sign */
+  while (isalnum(ls->current) || ls->current == '_')
+    save_and_next(ls);
+  save(ls, '\0');
+  buffreplace(ls, '.', ls->decpoint);  /* follow locale for decimal point */
+  if (!luaO_str2d(luaZ_buffer(ls->buff), &seminfo->r))  /* format error? */
+    trydecpoint(ls, seminfo); /* try to update decimal point separator */
+}
+
+
+static int skip_sep (LexState *ls) {
+  int count = 0;
+  int s = ls->current;
+  lua_assert(s == '[' || s == ']');
+  save_and_next(ls);
+  while (ls->current == '=') {
+    save_and_next(ls);
+    count++;
+  }
+  return (ls->current == s) ? count : (-count) - 1;
+}
+
+
+static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
+  int cont = 0;
+  (void)(cont);  /* avoid warnings when `cont' is not used */
+  save_and_next(ls);  /* skip 2nd `[' */
+  if (currIsNewline(ls))  /* string starts with a newline? */
+    inclinenumber(ls);  /* skip it */
+  for (;;) {
+    switch (ls->current) {
+      case EOZ:
+        luaX_lexerror(ls, (seminfo) ? "unfinished long string" :
+                                   "unfinished long comment", TK_EOS);
+        break;  /* to avoid warnings */
+#if defined(LUA_COMPAT_LSTR)
+      case '[': {
+        if (skip_sep(ls) == sep) {
+          save_and_next(ls);  /* skip 2nd `[' */
+          cont++;
+#if LUA_COMPAT_LSTR == 1
+          if (sep == 0)
+            luaX_lexerror(ls, "nesting of [[...]] is deprecated", '[');
+#endif
+        }
+        break;
+      }
+#endif
+      case ']': {
+        if (skip_sep(ls) == sep) {
+          save_and_next(ls);  /* skip 2nd `]' */
+#if defined(LUA_COMPAT_LSTR) && LUA_COMPAT_LSTR == 2
+          cont--;
+          if (sep == 0 && cont >= 0) break;
+#endif
+          goto endloop;
+        }
+        break;
+      }
+      case '\n':
+      case '\r': {
+        save(ls, '\n');
+        inclinenumber(ls);
+        if (!seminfo) luaZ_resetbuffer(ls->buff);  /* avoid wasting space */
+        break;
+      }
+      default: {
+        if (seminfo) save_and_next(ls);
+        else next(ls);
+      }
+    }
+  } endloop:
+  if (seminfo)
+    seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + (2 + sep),
+                                     luaZ_bufflen(ls->buff) - 2*(2 + sep));
+}
+
+
+static void read_string (LexState *ls, int del, SemInfo *seminfo) {
+  save_and_next(ls);
+  while (ls->current != del) {
+    switch (ls->current) {
+      case EOZ:
+        luaX_lexerror(ls, "unfinished string", TK_EOS);
+        continue;  /* to avoid warnings */
+      case '\n':
+      case '\r':
+        luaX_lexerror(ls, "unfinished string", TK_STRING);
+        continue;  /* to avoid warnings */
+      case '\\': {
+        int c;
+        next(ls);  /* do not save the `\' */
+        switch (ls->current) {
+          case 'a': c = '\a'; break;
+          case 'b': c = '\b'; break;
+          case 'f': c = '\f'; break;
+          case 'n': c = '\n'; break;
+          case 'r': c = '\r'; break;
+          case 't': c = '\t'; break;
+          case 'v': c = '\v'; break;
+          case '\n':  /* go through */
+          case '\r': save(ls, '\n'); inclinenumber(ls); continue;
+          case EOZ: continue;  /* will raise an error next loop */
+          default: {
+            if (!isdigit(ls->current))
+              save_and_next(ls);  /* handles \\, \", \', and \? */
+            else {  /* \xxx */
+              int i = 0;
+              c = 0;
+              do {
+                c = 10*c + (ls->current-'0');
+                next(ls);
+              } while (++i<3 && isdigit(ls->current));
+              if (c > UCHAR_MAX)
+                luaX_lexerror(ls, "escape sequence too large", TK_STRING);
+              save(ls, c);
+            }
+            continue;
+          }
+        }
+        save(ls, c);
+        next(ls);
+        continue;
+      }
+      default:
+        save_and_next(ls);
+    }
+  }
+  save_and_next(ls);  /* skip delimiter */
+  seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + 1,
+                                   luaZ_bufflen(ls->buff) - 2);
+}
+
+
+static int llex (LexState *ls, SemInfo *seminfo) {
+  luaZ_resetbuffer(ls->buff);
+  for (;;) {
+    switch (ls->current) {
+      case '\n':
+      case '\r': {
+        inclinenumber(ls);
+        continue;
+      }
+      case '-': {
+        next(ls);
+        if (ls->current != '-') return '-';
+        /* else is a comment */
+        next(ls);
+        if (ls->current == '[') {
+          int sep = skip_sep(ls);
+          luaZ_resetbuffer(ls->buff);  /* `skip_sep' may dirty the buffer */
+          if (sep >= 0) {
+            read_long_string(ls, NULL, sep);  /* long comment */
+            luaZ_resetbuffer(ls->buff);
+            continue;
+          }
+        }
+        /* else short comment */
+        while (!currIsNewline(ls) && ls->current != EOZ)
+          next(ls);
+        continue;
+      }
+      case '[': {
+        int sep = skip_sep(ls);
+        if (sep >= 0) {
+          read_long_string(ls, seminfo, sep);
+          return TK_STRING;
+        }
+        else if (sep == -1) return '[';
+        else luaX_lexerror(ls, "invalid long string delimiter", TK_STRING);
+      }
+      case '=': {
+        next(ls);
+        if (ls->current != '=') return '=';
+        else { next(ls); return TK_EQ; }
+      }
+      case '<': {
+        next(ls);
+        if (ls->current != '=') return '<';
+        else { next(ls); return TK_LE; }
+      }
+      case '>': {
+        next(ls);
+        if (ls->current != '=') return '>';
+        else { next(ls); return TK_GE; }
+      }
+      case '~': {
+        next(ls);
+        if (ls->current != '=') return '~';
+        else { next(ls); return TK_NE; }
+      }
+      case '"':
+      case '\'': {
+        read_string(ls, ls->current, seminfo);
+        return TK_STRING;
+      }
+      case '.': {
+        save_and_next(ls);
+        if (check_next(ls, ".")) {
+          if (check_next(ls, "."))
+            return TK_DOTS;   /* ... */
+          else return TK_CONCAT;   /* .. */
+        }
+        else if (!isdigit(ls->current)) return '.';
+        else {
+          read_numeral(ls, seminfo);
+          return TK_NUMBER;
+        }
+      }
+      case EOZ: {
+        return TK_EOS;
+      }
+      default: {
+        if (isspace(ls->current)) {
+          lua_assert(!currIsNewline(ls));
+          next(ls);
+          continue;
+        }
+        else if (isdigit(ls->current)) {
+          read_numeral(ls, seminfo);
+          return TK_NUMBER;
+        }
+        else if (isalpha(ls->current) || ls->current == '_') {
+          /* identifier or reserved word */
+          TString *ts;
+          do {
+            save_and_next(ls);
+          } while (isalnum(ls->current) || ls->current == '_');
+          ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
+                                  luaZ_bufflen(ls->buff));
+          if (ts->tsv.reserved > 0)  /* reserved word? */
+            return ts->tsv.reserved - 1 + FIRST_RESERVED;
+          else {
+            seminfo->ts = ts;
+            return TK_NAME;
+          }
+        }
+        else {
+          int c = ls->current;
+          next(ls);
+          return c;  /* single-char tokens (+ - / ...) */
+        }
+      }
+    }
+  }
+}
+
+
+void luaX_next (LexState *ls) {
+  ls->lastline = ls->linenumber;
+  if (ls->lookahead.token != TK_EOS) {  /* is there a look-ahead token? */
+    ls->t = ls->lookahead;  /* use this one */
+    ls->lookahead.token = TK_EOS;  /* and discharge it */
+  }
+  else
+    ls->t.token = llex(ls, &ls->t.seminfo);  /* read next token */
+}
+
+
+void luaX_lookahead (LexState *ls) {
+  lua_assert(ls->lookahead.token == TK_EOS);
+  ls->lookahead.token = llex(ls, &ls->lookahead.seminfo);
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/llex.h b/third_party/lua-src/lua-5.1.5/llex.h
new file mode 100644
index 00000000..a9201cee
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/llex.h
@@ -0,0 +1,81 @@
+/*
+** $Id: llex.h,v 1.58.1.1 2007/12/27 13:02:25 roberto Exp $
+** Lexical Analyzer
+** See Copyright Notice in lua.h
+*/
+
+#ifndef llex_h
+#define llex_h
+
+#include "lobject.h"
+#include "lzio.h"
+
+
+#define FIRST_RESERVED	257
+
+/* maximum length of a reserved word */
+#define TOKEN_LEN	(sizeof("function")/sizeof(char))
+
+
+/*
+* WARNING: if you change the order of this enumeration,
+* grep "ORDER RESERVED"
+*/
+enum RESERVED {
+  /* terminal symbols denoted by reserved words */
+  TK_AND = FIRST_RESERVED, TK_BREAK,
+  TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
+  TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
+  TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
+  /* other terminal symbols */
+  TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE, TK_NUMBER,
+  TK_NAME, TK_STRING, TK_EOS
+};
+
+/* number of reserved words */
+#define NUM_RESERVED	(cast(int, TK_WHILE-FIRST_RESERVED+1))
+
+
+/* array with token `names' */
+LUAI_DATA const char *const luaX_tokens [];
+
+
+typedef union {
+  lua_Number r;
+  TString *ts;
+} SemInfo;  /* semantics information */
+
+
+typedef struct Token {
+  int token;
+  SemInfo seminfo;
+} Token;
+
+
+typedef struct LexState {
+  int current;  /* current character (charint) */
+  int linenumber;  /* input line counter */
+  int lastline;  /* line of last token `consumed' */
+  Token t;  /* current token */
+  Token lookahead;  /* look ahead token */
+  struct FuncState *fs;  /* `FuncState' is private to the parser */
+  struct lua_State *L;
+  ZIO *z;  /* input stream */
+  Mbuffer *buff;  /* buffer for tokens */
+  TString *source;  /* current source name */
+  char decpoint;  /* locale decimal point */
+} LexState;
+
+
+LUAI_FUNC void luaX_init (lua_State *L);
+LUAI_FUNC void luaX_setinput (lua_State *L, LexState *ls, ZIO *z,
+                              TString *source);
+LUAI_FUNC TString *luaX_newstring (LexState *ls, const char *str, size_t l);
+LUAI_FUNC void luaX_next (LexState *ls);
+LUAI_FUNC void luaX_lookahead (LexState *ls);
+LUAI_FUNC void luaX_lexerror (LexState *ls, const char *msg, int token);
+LUAI_FUNC void luaX_syntaxerror (LexState *ls, const char *s);
+LUAI_FUNC const char *luaX_token2str (LexState *ls, int token);
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/llimits.h b/third_party/lua-src/lua-5.1.5/llimits.h
new file mode 100644
index 00000000..ca8dcb72
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/llimits.h
@@ -0,0 +1,128 @@
+/*
+** $Id: llimits.h,v 1.69.1.1 2007/12/27 13:02:25 roberto Exp $
+** Limits, basic types, and some other `installation-dependent' definitions
+** See Copyright Notice in lua.h
+*/
+
+#ifndef llimits_h
+#define llimits_h
+
+
+#include <limits.h>
+#include <stddef.h>
+
+
+#include "lua.h"
+
+
+typedef LUAI_UINT32 lu_int32;
+
+typedef LUAI_UMEM lu_mem;
+
+typedef LUAI_MEM l_mem;
+
+
+
+/* chars used as small naturals (so that `char' is reserved for characters) */
+typedef unsigned char lu_byte;
+
+
+#define MAX_SIZET	((size_t)(~(size_t)0)-2)
+
+#define MAX_LUMEM	((lu_mem)(~(lu_mem)0)-2)
+
+
+#define MAX_INT (INT_MAX-2)  /* maximum value of an int (-2 for safety) */
+
+/*
+** conversion of pointer to integer
+** this is for hashing only; there is no problem if the integer
+** cannot hold the whole pointer value
+*/
+#define IntPoint(p)  ((unsigned int)(lu_mem)(p))
+
+
+
+/* type to ensure maximum alignment */
+typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;
+
+
+/* result of a `usual argument conversion' over lua_Number */
+typedef LUAI_UACNUMBER l_uacNumber;
+
+
+/* internal assertions for in-house debugging */
+#ifdef lua_assert
+
+#define check_exp(c,e)		(lua_assert(c), (e))
+#define api_check(l,e)		lua_assert(e)
+
+#else
+
+#define lua_assert(c)		((void)0)
+#define check_exp(c,e)		(e)
+#define api_check		luai_apicheck
+
+#endif
+
+
+#ifndef UNUSED
+#define UNUSED(x)	((void)(x))	/* to avoid warnings */
+#endif
+
+
+#ifndef cast
+#define cast(t, exp)	((t)(exp))
+#endif
+
+#define cast_byte(i)	cast(lu_byte, (i))
+#define cast_num(i)	cast(lua_Number, (i))
+#define cast_int(i)	cast(int, (i))
+
+
+
+/*
+** type for virtual-machine instructions
+** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
+*/
+typedef lu_int32 Instruction;
+
+
+
+/* maximum stack for a Lua function */
+#define MAXSTACK	250
+
+
+
+/* minimum size for the string table (must be power of 2) */
+#ifndef MINSTRTABSIZE
+#define MINSTRTABSIZE	32
+#endif
+
+
+/* minimum size for string buffer */
+#ifndef LUA_MINBUFFER
+#define LUA_MINBUFFER	32
+#endif
+
+
+#ifndef lua_lock
+#define lua_lock(L)     ((void) 0) 
+#define lua_unlock(L)   ((void) 0)
+#endif
+
+#ifndef luai_threadyield
+#define luai_threadyield(L)     {lua_unlock(L); lua_lock(L);}
+#endif
+
+
+/*
+** macro to control inclusion of some hard tests on stack reallocation
+*/ 
+#ifndef HARDSTACKTESTS
+#define condhardstacktests(x)	((void)0)
+#else
+#define condhardstacktests(x)	x
+#endif
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lmathlib.c b/third_party/lua-src/lua-5.1.5/lmathlib.c
new file mode 100644
index 00000000..441fbf73
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lmathlib.c
@@ -0,0 +1,263 @@
+/*
+** $Id: lmathlib.c,v 1.67.1.1 2007/12/27 13:02:25 roberto Exp $
+** Standard mathematical library
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+#include <math.h>
+
+#define lmathlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#undef PI
+#define PI (3.14159265358979323846)
+#define RADIANS_PER_DEGREE (PI/180.0)
+
+
+
+static int math_abs (lua_State *L) {
+  lua_pushnumber(L, fabs(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_sin (lua_State *L) {
+  lua_pushnumber(L, sin(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_sinh (lua_State *L) {
+  lua_pushnumber(L, sinh(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_cos (lua_State *L) {
+  lua_pushnumber(L, cos(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_cosh (lua_State *L) {
+  lua_pushnumber(L, cosh(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_tan (lua_State *L) {
+  lua_pushnumber(L, tan(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_tanh (lua_State *L) {
+  lua_pushnumber(L, tanh(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_asin (lua_State *L) {
+  lua_pushnumber(L, asin(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_acos (lua_State *L) {
+  lua_pushnumber(L, acos(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_atan (lua_State *L) {
+  lua_pushnumber(L, atan(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_atan2 (lua_State *L) {
+  lua_pushnumber(L, atan2(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  return 1;
+}
+
+static int math_ceil (lua_State *L) {
+  lua_pushnumber(L, ceil(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_floor (lua_State *L) {
+  lua_pushnumber(L, floor(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_fmod (lua_State *L) {
+  lua_pushnumber(L, fmod(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  return 1;
+}
+
+static int math_modf (lua_State *L) {
+  double ip;
+  double fp = modf(luaL_checknumber(L, 1), &ip);
+  lua_pushnumber(L, ip);
+  lua_pushnumber(L, fp);
+  return 2;
+}
+
+static int math_sqrt (lua_State *L) {
+  lua_pushnumber(L, sqrt(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_pow (lua_State *L) {
+  lua_pushnumber(L, pow(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  return 1;
+}
+
+static int math_log (lua_State *L) {
+  lua_pushnumber(L, log(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_log10 (lua_State *L) {
+  lua_pushnumber(L, log10(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_exp (lua_State *L) {
+  lua_pushnumber(L, exp(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_deg (lua_State *L) {
+  lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);
+  return 1;
+}
+
+static int math_rad (lua_State *L) {
+  lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);
+  return 1;
+}
+
+static int math_frexp (lua_State *L) {
+  int e;
+  lua_pushnumber(L, frexp(luaL_checknumber(L, 1), &e));
+  lua_pushinteger(L, e);
+  return 2;
+}
+
+static int math_ldexp (lua_State *L) {
+  lua_pushnumber(L, ldexp(luaL_checknumber(L, 1), luaL_checkint(L, 2)));
+  return 1;
+}
+
+
+
+static int math_min (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  lua_Number dmin = luaL_checknumber(L, 1);
+  int i;
+  for (i=2; i<=n; i++) {
+    lua_Number d = luaL_checknumber(L, i);
+    if (d < dmin)
+      dmin = d;
+  }
+  lua_pushnumber(L, dmin);
+  return 1;
+}
+
+
+static int math_max (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  lua_Number dmax = luaL_checknumber(L, 1);
+  int i;
+  for (i=2; i<=n; i++) {
+    lua_Number d = luaL_checknumber(L, i);
+    if (d > dmax)
+      dmax = d;
+  }
+  lua_pushnumber(L, dmax);
+  return 1;
+}
+
+
+static int math_random (lua_State *L) {
+  /* the `%' avoids the (rare) case of r==1, and is needed also because on
+     some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */
+  lua_Number r = (lua_Number)(rand()%RAND_MAX) / (lua_Number)RAND_MAX;
+  switch (lua_gettop(L)) {  /* check number of arguments */
+    case 0: {  /* no arguments */
+      lua_pushnumber(L, r);  /* Number between 0 and 1 */
+      break;
+    }
+    case 1: {  /* only upper limit */
+      int u = luaL_checkint(L, 1);
+      luaL_argcheck(L, 1<=u, 1, "interval is empty");
+      lua_pushnumber(L, floor(r*u)+1);  /* int between 1 and `u' */
+      break;
+    }
+    case 2: {  /* lower and upper limits */
+      int l = luaL_checkint(L, 1);
+      int u = luaL_checkint(L, 2);
+      luaL_argcheck(L, l<=u, 2, "interval is empty");
+      lua_pushnumber(L, floor(r*(u-l+1))+l);  /* int between `l' and `u' */
+      break;
+    }
+    default: return luaL_error(L, "wrong number of arguments");
+  }
+  return 1;
+}
+
+
+static int math_randomseed (lua_State *L) {
+  srand(luaL_checkint(L, 1));
+  return 0;
+}
+
+
+static const luaL_Reg mathlib[] = {
+  {"abs",   math_abs},
+  {"acos",  math_acos},
+  {"asin",  math_asin},
+  {"atan2", math_atan2},
+  {"atan",  math_atan},
+  {"ceil",  math_ceil},
+  {"cosh",   math_cosh},
+  {"cos",   math_cos},
+  {"deg",   math_deg},
+  {"exp",   math_exp},
+  {"floor", math_floor},
+  {"fmod",   math_fmod},
+  {"frexp", math_frexp},
+  {"ldexp", math_ldexp},
+  {"log10", math_log10},
+  {"log",   math_log},
+  {"max",   math_max},
+  {"min",   math_min},
+  {"modf",   math_modf},
+  {"pow",   math_pow},
+  {"rad",   math_rad},
+  {"random",     math_random},
+  {"randomseed", math_randomseed},
+  {"sinh",   math_sinh},
+  {"sin",   math_sin},
+  {"sqrt",  math_sqrt},
+  {"tanh",   math_tanh},
+  {"tan",   math_tan},
+  {NULL, NULL}
+};
+
+
+/*
+** Open math library
+*/
+LUALIB_API int luaopen_math (lua_State *L) {
+  luaL_register(L, LUA_MATHLIBNAME, mathlib);
+  lua_pushnumber(L, PI);
+  lua_setfield(L, -2, "pi");
+  lua_pushnumber(L, HUGE_VAL);
+  lua_setfield(L, -2, "huge");
+#if defined(LUA_COMPAT_MOD)
+  lua_getfield(L, -1, "fmod");
+  lua_setfield(L, -2, "mod");
+#endif
+  return 1;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lmem.c b/third_party/lua-src/lua-5.1.5/lmem.c
new file mode 100644
index 00000000..ae7d8c96
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lmem.c
@@ -0,0 +1,86 @@
+/*
+** $Id: lmem.c,v 1.70.1.1 2007/12/27 13:02:25 roberto Exp $
+** Interface to Memory Manager
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define lmem_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+
+/*
+** About the realloc function:
+** void * frealloc (void *ud, void *ptr, size_t osize, size_t nsize);
+** (`osize' is the old size, `nsize' is the new size)
+**
+** Lua ensures that (ptr == NULL) iff (osize == 0).
+**
+** * frealloc(ud, NULL, 0, x) creates a new block of size `x'
+**
+** * frealloc(ud, p, x, 0) frees the block `p'
+** (in this specific case, frealloc must return NULL).
+** particularly, frealloc(ud, NULL, 0, 0) does nothing
+** (which is equivalent to free(NULL) in ANSI C)
+**
+** frealloc returns NULL if it cannot create or reallocate the area
+** (any reallocation to an equal or smaller size cannot fail!)
+*/
+
+
+
+#define MINSIZEARRAY	4
+
+
+void *luaM_growaux_ (lua_State *L, void *block, int *size, size_t size_elems,
+                     int limit, const char *errormsg) {
+  void *newblock;
+  int newsize;
+  if (*size >= limit/2) {  /* cannot double it? */
+    if (*size >= limit)  /* cannot grow even a little? */
+      luaG_runerror(L, errormsg);
+    newsize = limit;  /* still have at least one free place */
+  }
+  else {
+    newsize = (*size)*2;
+    if (newsize < MINSIZEARRAY)
+      newsize = MINSIZEARRAY;  /* minimum size */
+  }
+  newblock = luaM_reallocv(L, block, *size, newsize, size_elems);
+  *size = newsize;  /* update only when everything else is OK */
+  return newblock;
+}
+
+
+void *luaM_toobig (lua_State *L) {
+  luaG_runerror(L, "memory allocation error: block too big");
+  return NULL;  /* to avoid warnings */
+}
+
+
+
+/*
+** generic allocation routine.
+*/
+void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
+  global_State *g = G(L);
+  lua_assert((osize == 0) == (block == NULL));
+  block = (*g->frealloc)(g->ud, block, osize, nsize);
+  if (block == NULL && nsize > 0)
+    luaD_throw(L, LUA_ERRMEM);
+  lua_assert((nsize == 0) == (block == NULL));
+  g->totalbytes = (g->totalbytes - osize) + nsize;
+  return block;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lmem.h b/third_party/lua-src/lua-5.1.5/lmem.h
new file mode 100644
index 00000000..7c2dcb32
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lmem.h
@@ -0,0 +1,49 @@
+/*
+** $Id: lmem.h,v 1.31.1.1 2007/12/27 13:02:25 roberto Exp $
+** Interface to Memory Manager
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lmem_h
+#define lmem_h
+
+
+#include <stddef.h>
+
+#include "llimits.h"
+#include "lua.h"
+
+#define MEMERRMSG	"not enough memory"
+
+
+#define luaM_reallocv(L,b,on,n,e) \
+	((cast(size_t, (n)+1) <= MAX_SIZET/(e)) ?  /* +1 to avoid warnings */ \
+		luaM_realloc_(L, (b), (on)*(e), (n)*(e)) : \
+		luaM_toobig(L))
+
+#define luaM_freemem(L, b, s)	luaM_realloc_(L, (b), (s), 0)
+#define luaM_free(L, b)		luaM_realloc_(L, (b), sizeof(*(b)), 0)
+#define luaM_freearray(L, b, n, t)   luaM_reallocv(L, (b), n, 0, sizeof(t))
+
+#define luaM_malloc(L,t)	luaM_realloc_(L, NULL, 0, (t))
+#define luaM_new(L,t)		cast(t *, luaM_malloc(L, sizeof(t)))
+#define luaM_newvector(L,n,t) \
+		cast(t *, luaM_reallocv(L, NULL, 0, n, sizeof(t)))
+
+#define luaM_growvector(L,v,nelems,size,t,limit,e) \
+          if ((nelems)+1 > (size)) \
+            ((v)=cast(t *, luaM_growaux_(L,v,&(size),sizeof(t),limit,e)))
+
+#define luaM_reallocvector(L, v,oldn,n,t) \
+   ((v)=cast(t *, luaM_reallocv(L, v, oldn, n, sizeof(t))))
+
+
+LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize,
+                                                          size_t size);
+LUAI_FUNC void *luaM_toobig (lua_State *L);
+LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int *size,
+                               size_t size_elem, int limit,
+                               const char *errormsg);
+
+#endif
+
diff --git a/third_party/lua-src/lua-5.1.5/loadlib.c b/third_party/lua-src/lua-5.1.5/loadlib.c
new file mode 100644
index 00000000..6158c535
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/loadlib.c
@@ -0,0 +1,666 @@
+/*
+** $Id: loadlib.c,v 1.52.1.4 2009/09/09 13:17:16 roberto Exp $
+** Dynamic library loader for Lua
+** See Copyright Notice in lua.h
+**
+** This module contains an implementation of loadlib for Unix systems
+** that have dlfcn, an implementation for Darwin (Mac OS X), an
+** implementation for Windows, and a stub for other systems.
+*/
+
+
+#include <stdlib.h>
+#include <string.h>
+
+
+#define loadlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/* prefix for open functions in C libraries */
+#define LUA_POF		"luaopen_"
+
+/* separator for open functions in C libraries */
+#define LUA_OFSEP	"_"
+
+
+#define LIBPREFIX	"LOADLIB: "
+
+#define POF		LUA_POF
+#define LIB_FAIL	"open"
+
+
+/* error codes for ll_loadfunc */
+#define ERRLIB		1
+#define ERRFUNC		2
+
+#define setprogdir(L)		((void)0)
+
+
+static void ll_unloadlib (void *lib);
+static void *ll_load (lua_State *L, const char *path);
+static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
+
+
+
+#if defined(LUA_DL_DLOPEN)
+/*
+** {========================================================================
+** This is an implementation of loadlib based on the dlfcn interface.
+** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
+** NetBSD, AIX 4.2, HPUX 11, and  probably most other Unix flavors, at least
+** as an emulation layer on top of native functions.
+** =========================================================================
+*/
+
+#include <dlfcn.h>
+
+static void ll_unloadlib (void *lib) {
+  dlclose(lib);
+}
+
+
+static void *ll_load (lua_State *L, const char *path) {
+  void *lib = dlopen(path, RTLD_NOW);
+  if (lib == NULL) lua_pushstring(L, dlerror());
+  return lib;
+}
+
+
+static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
+  lua_CFunction f = (lua_CFunction)dlsym(lib, sym);
+  if (f == NULL) lua_pushstring(L, dlerror());
+  return f;
+}
+
+/* }====================================================== */
+
+
+
+#elif defined(LUA_DL_DLL)
+/*
+** {======================================================================
+** This is an implementation of loadlib for Windows using native functions.
+** =======================================================================
+*/
+
+#include <windows.h>
+
+
+#undef setprogdir
+
+static void setprogdir (lua_State *L) {
+  char buff[MAX_PATH + 1];
+  char *lb;
+  DWORD nsize = sizeof(buff)/sizeof(char);
+  DWORD n = GetModuleFileNameA(NULL, buff, nsize);
+  if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
+    luaL_error(L, "unable to get ModuleFileName");
+  else {
+    *lb = '\0';
+    luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
+    lua_remove(L, -2);  /* remove original string */
+  }
+}
+
+
+static void pusherror (lua_State *L) {
+  int error = GetLastError();
+  char buffer[128];
+  if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
+      NULL, error, 0, buffer, sizeof(buffer), NULL))
+    lua_pushstring(L, buffer);
+  else
+    lua_pushfstring(L, "system error %d\n", error);
+}
+
+static void ll_unloadlib (void *lib) {
+  FreeLibrary((HINSTANCE)lib);
+}
+
+
+static void *ll_load (lua_State *L, const char *path) {
+  HINSTANCE lib = LoadLibraryA(path);
+  if (lib == NULL) pusherror(L);
+  return lib;
+}
+
+
+static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
+  lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
+  if (f == NULL) pusherror(L);
+  return f;
+}
+
+/* }====================================================== */
+
+
+
+#elif defined(LUA_DL_DYLD)
+/*
+** {======================================================================
+** Native Mac OS X / Darwin Implementation
+** =======================================================================
+*/
+
+#include <mach-o/dyld.h>
+
+
+/* Mac appends a `_' before C function names */
+#undef POF
+#define POF	"_" LUA_POF
+
+
+static void pusherror (lua_State *L) {
+  const char *err_str;
+  const char *err_file;
+  NSLinkEditErrors err;
+  int err_num;
+  NSLinkEditError(&err, &err_num, &err_file, &err_str);
+  lua_pushstring(L, err_str);
+}
+
+
+static const char *errorfromcode (NSObjectFileImageReturnCode ret) {
+  switch (ret) {
+    case NSObjectFileImageInappropriateFile:
+      return "file is not a bundle";
+    case NSObjectFileImageArch:
+      return "library is for wrong CPU type";
+    case NSObjectFileImageFormat:
+      return "bad format";
+    case NSObjectFileImageAccess:
+      return "cannot access file";
+    case NSObjectFileImageFailure:
+    default:
+      return "unable to load library";
+  }
+}
+
+
+static void ll_unloadlib (void *lib) {
+  NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES);
+}
+
+
+static void *ll_load (lua_State *L, const char *path) {
+  NSObjectFileImage img;
+  NSObjectFileImageReturnCode ret;
+  /* this would be a rare case, but prevents crashing if it happens */
+  if(!_dyld_present()) {
+    lua_pushliteral(L, "dyld not present");
+    return NULL;
+  }
+  ret = NSCreateObjectFileImageFromFile(path, &img);
+  if (ret == NSObjectFileImageSuccess) {
+    NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE |
+                       NSLINKMODULE_OPTION_RETURN_ON_ERROR);
+    NSDestroyObjectFileImage(img);
+    if (mod == NULL) pusherror(L);
+    return mod;
+  }
+  lua_pushstring(L, errorfromcode(ret));
+  return NULL;
+}
+
+
+static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
+  NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym);
+  if (nss == NULL) {
+    lua_pushfstring(L, "symbol " LUA_QS " not found", sym);
+    return NULL;
+  }
+  return (lua_CFunction)NSAddressOfSymbol(nss);
+}
+
+/* }====================================================== */
+
+
+
+#else
+/*
+** {======================================================
+** Fallback for other systems
+** =======================================================
+*/
+
+#undef LIB_FAIL
+#define LIB_FAIL	"absent"
+
+
+#define DLMSG	"dynamic libraries not enabled; check your Lua installation"
+
+
+static void ll_unloadlib (void *lib) {
+  (void)lib;  /* to avoid warnings */
+}
+
+
+static void *ll_load (lua_State *L, const char *path) {
+  (void)path;  /* to avoid warnings */
+  lua_pushliteral(L, DLMSG);
+  return NULL;
+}
+
+
+static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
+  (void)lib; (void)sym;  /* to avoid warnings */
+  lua_pushliteral(L, DLMSG);
+  return NULL;
+}
+
+/* }====================================================== */
+#endif
+
+
+
+static void **ll_register (lua_State *L, const char *path) {
+  void **plib;
+  lua_pushfstring(L, "%s%s", LIBPREFIX, path);
+  lua_gettable(L, LUA_REGISTRYINDEX);  /* check library in registry? */
+  if (!lua_isnil(L, -1))  /* is there an entry? */
+    plib = (void **)lua_touserdata(L, -1);
+  else {  /* no entry yet; create one */
+    lua_pop(L, 1);
+    plib = (void **)lua_newuserdata(L, sizeof(const void *));
+    *plib = NULL;
+    luaL_getmetatable(L, "_LOADLIB");
+    lua_setmetatable(L, -2);
+    lua_pushfstring(L, "%s%s", LIBPREFIX, path);
+    lua_pushvalue(L, -2);
+    lua_settable(L, LUA_REGISTRYINDEX);
+  }
+  return plib;
+}
+
+
+/*
+** __gc tag method: calls library's `ll_unloadlib' function with the lib
+** handle
+*/
+static int gctm (lua_State *L) {
+  void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
+  if (*lib) ll_unloadlib(*lib);
+  *lib = NULL;  /* mark library as closed */
+  return 0;
+}
+
+
+static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
+  void **reg = ll_register(L, path);
+  if (*reg == NULL) *reg = ll_load(L, path);
+  if (*reg == NULL)
+    return ERRLIB;  /* unable to load library */
+  else {
+    lua_CFunction f = ll_sym(L, *reg, sym);
+    if (f == NULL)
+      return ERRFUNC;  /* unable to find function */
+    lua_pushcfunction(L, f);
+    return 0;  /* return function */
+  }
+}
+
+
+static int ll_loadlib (lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+  const char *init = luaL_checkstring(L, 2);
+  int stat = ll_loadfunc(L, path, init);
+  if (stat == 0)  /* no errors? */
+    return 1;  /* return the loaded function */
+  else {  /* error; error message is on stack top */
+    lua_pushnil(L);
+    lua_insert(L, -2);
+    lua_pushstring(L, (stat == ERRLIB) ?  LIB_FAIL : "init");
+    return 3;  /* return nil, error message, and where */
+  }
+}
+
+
+
+/*
+** {======================================================
+** 'require' function
+** =======================================================
+*/
+
+
+static int readable (const char *filename) {
+  FILE *f = fopen(filename, "r");  /* try to open file */
+  if (f == NULL) return 0;  /* open failed */
+  fclose(f);
+  return 1;
+}
+
+
+static const char *pushnexttemplate (lua_State *L, const char *path) {
+  const char *l;
+  while (*path == *LUA_PATHSEP) path++;  /* skip separators */
+  if (*path == '\0') return NULL;  /* no more templates */
+  l = strchr(path, *LUA_PATHSEP);  /* find next separator */
+  if (l == NULL) l = path + strlen(path);
+  lua_pushlstring(L, path, l - path);  /* template */
+  return l;
+}
+
+
+static const char *findfile (lua_State *L, const char *name,
+                                           const char *pname) {
+  const char *path;
+  name = luaL_gsub(L, name, ".", LUA_DIRSEP);
+  lua_getfield(L, LUA_ENVIRONINDEX, pname);
+  path = lua_tostring(L, -1);
+  if (path == NULL)
+    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+  lua_pushliteral(L, "");  /* error accumulator */
+  while ((path = pushnexttemplate(L, path)) != NULL) {
+    const char *filename;
+    filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
+    lua_remove(L, -2);  /* remove path template */
+    if (readable(filename))  /* does file exist and is readable? */
+      return filename;  /* return that file name */
+    lua_pushfstring(L, "\n\tno file " LUA_QS, filename);
+    lua_remove(L, -2);  /* remove file name */
+    lua_concat(L, 2);  /* add entry to possible error message */
+  }
+  return NULL;  /* not found */
+}
+
+
+static void loaderror (lua_State *L, const char *filename) {
+  luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
+                lua_tostring(L, 1), filename, lua_tostring(L, -1));
+}
+
+
+static int loader_Lua (lua_State *L) {
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  filename = findfile(L, name, "path");
+  if (filename == NULL) return 1;  /* library not found in this path */
+  if (luaL_loadfile(L, filename) != 0)
+    loaderror(L, filename);
+  return 1;  /* library loaded successfully */
+}
+
+
+static const char *mkfuncname (lua_State *L, const char *modname) {
+  const char *funcname;
+  const char *mark = strchr(modname, *LUA_IGMARK);
+  if (mark) modname = mark + 1;
+  funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
+  funcname = lua_pushfstring(L, POF"%s", funcname);
+  lua_remove(L, -2);  /* remove 'gsub' result */
+  return funcname;
+}
+
+
+static int loader_C (lua_State *L) {
+  const char *funcname;
+  const char *name = luaL_checkstring(L, 1);
+  const char *filename = findfile(L, name, "cpath");
+  if (filename == NULL) return 1;  /* library not found in this path */
+  funcname = mkfuncname(L, name);
+  if (ll_loadfunc(L, filename, funcname) != 0)
+    loaderror(L, filename);
+  return 1;  /* library loaded successfully */
+}
+
+
+static int loader_Croot (lua_State *L) {
+  const char *funcname;
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  const char *p = strchr(name, '.');
+  int stat;
+  if (p == NULL) return 0;  /* is root */
+  lua_pushlstring(L, name, p - name);
+  filename = findfile(L, lua_tostring(L, -1), "cpath");
+  if (filename == NULL) return 1;  /* root not found */
+  funcname = mkfuncname(L, name);
+  if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
+    if (stat != ERRFUNC) loaderror(L, filename);  /* real error */
+    lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
+                       name, filename);
+    return 1;  /* function not found */
+  }
+  return 1;
+}
+
+
+static int loader_preload (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  lua_getfield(L, LUA_ENVIRONINDEX, "preload");
+  if (!lua_istable(L, -1))
+    luaL_error(L, LUA_QL("package.preload") " must be a table");
+  lua_getfield(L, -1, name);
+  if (lua_isnil(L, -1))  /* not found? */
+    lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
+  return 1;
+}
+
+
+static const int sentinel_ = 0;
+#define sentinel	((void *)&sentinel_)
+
+
+static int ll_require (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  int i;
+  lua_settop(L, 1);  /* _LOADED table will be at index 2 */
+  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_getfield(L, 2, name);
+  if (lua_toboolean(L, -1)) {  /* is it there? */
+    if (lua_touserdata(L, -1) == sentinel)  /* check loops */
+      luaL_error(L, "loop or previous error loading module " LUA_QS, name);
+    return 1;  /* package is already loaded */
+  }
+  /* else must load it; iterate over available loaders */
+  lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
+  if (!lua_istable(L, -1))
+    luaL_error(L, LUA_QL("package.loaders") " must be a table");
+  lua_pushliteral(L, "");  /* error message accumulator */
+  for (i=1; ; i++) {
+    lua_rawgeti(L, -2, i);  /* get a loader */
+    if (lua_isnil(L, -1))
+      luaL_error(L, "module " LUA_QS " not found:%s",
+                    name, lua_tostring(L, -2));
+    lua_pushstring(L, name);
+    lua_call(L, 1, 1);  /* call it */
+    if (lua_isfunction(L, -1))  /* did it find module? */
+      break;  /* module loaded successfully */
+    else if (lua_isstring(L, -1))  /* loader returned error message? */
+      lua_concat(L, 2);  /* accumulate it */
+    else
+      lua_pop(L, 1);
+  }
+  lua_pushlightuserdata(L, sentinel);
+  lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */
+  lua_pushstring(L, name);  /* pass name as argument to module */
+  lua_call(L, 1, 1);  /* run loaded module */
+  if (!lua_isnil(L, -1))  /* non-nil return? */
+    lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
+  lua_getfield(L, 2, name);
+  if (lua_touserdata(L, -1) == sentinel) {   /* module did not set a value? */
+    lua_pushboolean(L, 1);  /* use true as result */
+    lua_pushvalue(L, -1);  /* extra copy to be returned */
+    lua_setfield(L, 2, name);  /* _LOADED[name] = true */
+  }
+  return 1;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** 'module' function
+** =======================================================
+*/
+  
+
+static void setfenv (lua_State *L) {
+  lua_Debug ar;
+  if (lua_getstack(L, 1, &ar) == 0 ||
+      lua_getinfo(L, "f", &ar) == 0 ||  /* get calling function */
+      lua_iscfunction(L, -1))
+    luaL_error(L, LUA_QL("module") " not called from a Lua function");
+  lua_pushvalue(L, -2);
+  lua_setfenv(L, -2);
+  lua_pop(L, 1);
+}
+
+
+static void dooptions (lua_State *L, int n) {
+  int i;
+  for (i = 2; i <= n; i++) {
+    lua_pushvalue(L, i);  /* get option (a function) */
+    lua_pushvalue(L, -2);  /* module */
+    lua_call(L, 1, 0);
+  }
+}
+
+
+static void modinit (lua_State *L, const char *modname) {
+  const char *dot;
+  lua_pushvalue(L, -1);
+  lua_setfield(L, -2, "_M");  /* module._M = module */
+  lua_pushstring(L, modname);
+  lua_setfield(L, -2, "_NAME");
+  dot = strrchr(modname, '.');  /* look for last dot in module name */
+  if (dot == NULL) dot = modname;
+  else dot++;
+  /* set _PACKAGE as package name (full module name minus last part) */
+  lua_pushlstring(L, modname, dot - modname);
+  lua_setfield(L, -2, "_PACKAGE");
+}
+
+
+static int ll_module (lua_State *L) {
+  const char *modname = luaL_checkstring(L, 1);
+  int loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
+  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
+  if (!lua_istable(L, -1)) {  /* not found? */
+    lua_pop(L, 1);  /* remove previous result */
+    /* try global variable (and create one if it does not exist) */
+    if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)
+      return luaL_error(L, "name conflict for module " LUA_QS, modname);
+    lua_pushvalue(L, -1);
+    lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
+  }
+  /* check whether table already has a _NAME field */
+  lua_getfield(L, -1, "_NAME");
+  if (!lua_isnil(L, -1))  /* is table an initialized module? */
+    lua_pop(L, 1);
+  else {  /* no; initialize it */
+    lua_pop(L, 1);
+    modinit(L, modname);
+  }
+  lua_pushvalue(L, -1);
+  setfenv(L);
+  dooptions(L, loaded - 1);
+  return 0;
+}
+
+
+static int ll_seeall (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  if (!lua_getmetatable(L, 1)) {
+    lua_createtable(L, 0, 1); /* create new metatable */
+    lua_pushvalue(L, -1);
+    lua_setmetatable(L, 1);
+  }
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  lua_setfield(L, -2, "__index");  /* mt.__index = _G */
+  return 0;
+}
+
+
+/* }====================================================== */
+
+
+
+/* auxiliary mark (for internal use) */
+#define AUXMARK		"\1"
+
+static void setpath (lua_State *L, const char *fieldname, const char *envname,
+                                   const char *def) {
+  const char *path = getenv(envname);
+  if (path == NULL)  /* no environment variable? */
+    lua_pushstring(L, def);  /* use default */
+  else {
+    /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
+    path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
+                              LUA_PATHSEP AUXMARK LUA_PATHSEP);
+    luaL_gsub(L, path, AUXMARK, def);
+    lua_remove(L, -2);
+  }
+  setprogdir(L);
+  lua_setfield(L, -2, fieldname);
+}
+
+
+static const luaL_Reg pk_funcs[] = {
+  {"loadlib", ll_loadlib},
+  {"seeall", ll_seeall},
+  {NULL, NULL}
+};
+
+
+static const luaL_Reg ll_funcs[] = {
+  {"module", ll_module},
+  {"require", ll_require},
+  {NULL, NULL}
+};
+
+
+static const lua_CFunction loaders[] =
+  {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
+
+
+LUALIB_API int luaopen_package (lua_State *L) {
+  int i;
+  /* create new type _LOADLIB */
+  luaL_newmetatable(L, "_LOADLIB");
+  lua_pushcfunction(L, gctm);
+  lua_setfield(L, -2, "__gc");
+  /* create `package' table */
+  luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
+#if defined(LUA_COMPAT_LOADLIB) 
+  lua_getfield(L, -1, "loadlib");
+  lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
+#endif
+  lua_pushvalue(L, -1);
+  lua_replace(L, LUA_ENVIRONINDEX);
+  /* create `loaders' table */
+  lua_createtable(L, sizeof(loaders)/sizeof(loaders[0]) - 1, 0);
+  /* fill it with pre-defined loaders */
+  for (i=0; loaders[i] != NULL; i++) {
+    lua_pushcfunction(L, loaders[i]);
+    lua_rawseti(L, -2, i+1);
+  }
+  lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */
+  setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */
+  setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
+  /* store config information */
+  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
+                     LUA_EXECDIR "\n" LUA_IGMARK);
+  lua_setfield(L, -2, "config");
+  /* set field `loaded' */
+  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
+  lua_setfield(L, -2, "loaded");
+  /* set field `preload' */
+  lua_newtable(L);
+  lua_setfield(L, -2, "preload");
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  luaL_register(L, NULL, ll_funcs);  /* open lib into global table */
+  lua_pop(L, 1);
+  return 1;  /* return 'package' table */
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lobject.c b/third_party/lua-src/lua-5.1.5/lobject.c
new file mode 100644
index 00000000..4ff50732
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lobject.c
@@ -0,0 +1,214 @@
+/*
+** $Id: lobject.c,v 2.22.1.1 2007/12/27 13:02:25 roberto Exp $
+** Some generic functions over Lua objects
+** See Copyright Notice in lua.h
+*/
+
+#include <ctype.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lobject_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldo.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "lvm.h"
+
+
+
+const TValue luaO_nilobject_ = {{NULL}, LUA_TNIL};
+
+
+/*
+** converts an integer to a "floating point byte", represented as
+** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if
+** eeeee != 0 and (xxx) otherwise.
+*/
+int luaO_int2fb (unsigned int x) {
+  int e = 0;  /* expoent */
+  while (x >= 16) {
+    x = (x+1) >> 1;
+    e++;
+  }
+  if (x < 8) return x;
+  else return ((e+1) << 3) | (cast_int(x) - 8);
+}
+
+
+/* converts back */
+int luaO_fb2int (int x) {
+  int e = (x >> 3) & 31;
+  if (e == 0) return x;
+  else return ((x & 7)+8) << (e - 1);
+}
+
+
+int luaO_log2 (unsigned int x) {
+  static const lu_byte log_2[256] = {
+    0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+    6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
+  };
+  int l = -1;
+  while (x >= 256) { l += 8; x >>= 8; }
+  return l + log_2[x];
+
+}
+
+
+int luaO_rawequalObj (const TValue *t1, const TValue *t2) {
+  if (ttype(t1) != ttype(t2)) return 0;
+  else switch (ttype(t1)) {
+    case LUA_TNIL:
+      return 1;
+    case LUA_TNUMBER:
+      return luai_numeq(nvalue(t1), nvalue(t2));
+    case LUA_TBOOLEAN:
+      return bvalue(t1) == bvalue(t2);  /* boolean true must be 1 !! */
+    case LUA_TLIGHTUSERDATA:
+      return pvalue(t1) == pvalue(t2);
+    default:
+      lua_assert(iscollectable(t1));
+      return gcvalue(t1) == gcvalue(t2);
+  }
+}
+
+
+int luaO_str2d (const char *s, lua_Number *result) {
+  char *endptr;
+  *result = lua_str2number(s, &endptr);
+  if (endptr == s) return 0;  /* conversion failed */
+  if (*endptr == 'x' || *endptr == 'X')  /* maybe an hexadecimal constant? */
+    *result = cast_num(strtoul(s, &endptr, 16));
+  if (*endptr == '\0') return 1;  /* most common case */
+  while (isspace(cast(unsigned char, *endptr))) endptr++;
+  if (*endptr != '\0') return 0;  /* invalid trailing characters? */
+  return 1;
+}
+
+
+
+static void pushstr (lua_State *L, const char *str) {
+  setsvalue2s(L, L->top, luaS_new(L, str));
+  incr_top(L);
+}
+
+
+/* this function handles only `%d', `%c', %f, %p, and `%s' formats */
+const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
+  int n = 1;
+  pushstr(L, "");
+  for (;;) {
+    const char *e = strchr(fmt, '%');
+    if (e == NULL) break;
+    setsvalue2s(L, L->top, luaS_newlstr(L, fmt, e-fmt));
+    incr_top(L);
+    switch (*(e+1)) {
+      case 's': {
+        const char *s = va_arg(argp, char *);
+        if (s == NULL) s = "(null)";
+        pushstr(L, s);
+        break;
+      }
+      case 'c': {
+        char buff[2];
+        buff[0] = cast(char, va_arg(argp, int));
+        buff[1] = '\0';
+        pushstr(L, buff);
+        break;
+      }
+      case 'd': {
+        setnvalue(L->top, cast_num(va_arg(argp, int)));
+        incr_top(L);
+        break;
+      }
+      case 'f': {
+        setnvalue(L->top, cast_num(va_arg(argp, l_uacNumber)));
+        incr_top(L);
+        break;
+      }
+      case 'p': {
+        char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */
+        sprintf(buff, "%p", va_arg(argp, void *));
+        pushstr(L, buff);
+        break;
+      }
+      case '%': {
+        pushstr(L, "%");
+        break;
+      }
+      default: {
+        char buff[3];
+        buff[0] = '%';
+        buff[1] = *(e+1);
+        buff[2] = '\0';
+        pushstr(L, buff);
+        break;
+      }
+    }
+    n += 2;
+    fmt = e+2;
+  }
+  pushstr(L, fmt);
+  luaV_concat(L, n+1, cast_int(L->top - L->base) - 1);
+  L->top -= n;
+  return svalue(L->top - 1);
+}
+
+
+const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {
+  const char *msg;
+  va_list argp;
+  va_start(argp, fmt);
+  msg = luaO_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  return msg;
+}
+
+
+void luaO_chunkid (char *out, const char *source, size_t bufflen) {
+  if (*source == '=') {
+    strncpy(out, source+1, bufflen);  /* remove first char */
+    out[bufflen-1] = '\0';  /* ensures null termination */
+  }
+  else {  /* out = "source", or "...source" */
+    if (*source == '@') {
+      size_t l;
+      source++;  /* skip the `@' */
+      bufflen -= sizeof(" '...' ");
+      l = strlen(source);
+      strcpy(out, "");
+      if (l > bufflen) {
+        source += (l-bufflen);  /* get last part of file name */
+        strcat(out, "...");
+      }
+      strcat(out, source);
+    }
+    else {  /* out = [string "string"] */
+      size_t len = strcspn(source, "\n\r");  /* stop at first newline */
+      bufflen -= sizeof(" [string \"...\"] ");
+      if (len > bufflen) len = bufflen;
+      strcpy(out, "[string \"");
+      if (source[len] != '\0') {  /* must truncate? */
+        strncat(out, source, len);
+        strcat(out, "...");
+      }
+      else
+        strcat(out, source);
+      strcat(out, "\"]");
+    }
+  }
+}
diff --git a/third_party/lua-src/lua-5.1.5/lobject.h b/third_party/lua-src/lua-5.1.5/lobject.h
new file mode 100644
index 00000000..f1e447ef
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lobject.h
@@ -0,0 +1,381 @@
+/*
+** $Id: lobject.h,v 2.20.1.2 2008/08/06 13:29:48 roberto Exp $
+** Type definitions for Lua objects
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lobject_h
+#define lobject_h
+
+
+#include <stdarg.h>
+
+
+#include "llimits.h"
+#include "lua.h"
+
+
+/* tags for values visible from Lua */
+#define LAST_TAG	LUA_TTHREAD
+
+#define NUM_TAGS	(LAST_TAG+1)
+
+
+/*
+** Extra tags for non-values
+*/
+#define LUA_TPROTO	(LAST_TAG+1)
+#define LUA_TUPVAL	(LAST_TAG+2)
+#define LUA_TDEADKEY	(LAST_TAG+3)
+
+
+/*
+** Union of all collectable objects
+*/
+typedef union GCObject GCObject;
+
+
+/*
+** Common Header for all collectable objects (in macro form, to be
+** included in other objects)
+*/
+#define CommonHeader	GCObject *next; lu_byte tt; lu_byte marked
+
+
+/*
+** Common header in struct form
+*/
+typedef struct GCheader {
+  CommonHeader;
+} GCheader;
+
+
+
+
+/*
+** Union of all Lua values
+*/
+typedef union {
+  GCObject *gc;
+  void *p;
+  lua_Number n;
+  int b;
+} Value;
+
+
+/*
+** Tagged Values
+*/
+
+#define TValuefields	Value value; int tt
+
+typedef struct lua_TValue {
+  TValuefields;
+} TValue;
+
+
+/* Macros to test type */
+#define ttisnil(o)	(ttype(o) == LUA_TNIL)
+#define ttisnumber(o)	(ttype(o) == LUA_TNUMBER)
+#define ttisstring(o)	(ttype(o) == LUA_TSTRING)
+#define ttistable(o)	(ttype(o) == LUA_TTABLE)
+#define ttisfunction(o)	(ttype(o) == LUA_TFUNCTION)
+#define ttisboolean(o)	(ttype(o) == LUA_TBOOLEAN)
+#define ttisuserdata(o)	(ttype(o) == LUA_TUSERDATA)
+#define ttisthread(o)	(ttype(o) == LUA_TTHREAD)
+#define ttislightuserdata(o)	(ttype(o) == LUA_TLIGHTUSERDATA)
+
+/* Macros to access values */
+#define ttype(o)	((o)->tt)
+#define gcvalue(o)	check_exp(iscollectable(o), (o)->value.gc)
+#define pvalue(o)	check_exp(ttislightuserdata(o), (o)->value.p)
+#define nvalue(o)	check_exp(ttisnumber(o), (o)->value.n)
+#define rawtsvalue(o)	check_exp(ttisstring(o), &(o)->value.gc->ts)
+#define tsvalue(o)	(&rawtsvalue(o)->tsv)
+#define rawuvalue(o)	check_exp(ttisuserdata(o), &(o)->value.gc->u)
+#define uvalue(o)	(&rawuvalue(o)->uv)
+#define clvalue(o)	check_exp(ttisfunction(o), &(o)->value.gc->cl)
+#define hvalue(o)	check_exp(ttistable(o), &(o)->value.gc->h)
+#define bvalue(o)	check_exp(ttisboolean(o), (o)->value.b)
+#define thvalue(o)	check_exp(ttisthread(o), &(o)->value.gc->th)
+
+#define l_isfalse(o)	(ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))
+
+/*
+** for internal debug only
+*/
+#define checkconsistency(obj) \
+  lua_assert(!iscollectable(obj) || (ttype(obj) == (obj)->value.gc->gch.tt))
+
+#define checkliveness(g,obj) \
+  lua_assert(!iscollectable(obj) || \
+  ((ttype(obj) == (obj)->value.gc->gch.tt) && !isdead(g, (obj)->value.gc)))
+
+
+/* Macros to set values */
+#define setnilvalue(obj) ((obj)->tt=LUA_TNIL)
+
+#define setnvalue(obj,x) \
+  { TValue *i_o=(obj); i_o->value.n=(x); i_o->tt=LUA_TNUMBER; }
+
+#define setpvalue(obj,x) \
+  { TValue *i_o=(obj); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
+
+#define setbvalue(obj,x) \
+  { TValue *i_o=(obj); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
+
+#define setsvalue(L,obj,x) \
+  { TValue *i_o=(obj); \
+    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TSTRING; \
+    checkliveness(G(L),i_o); }
+
+#define setuvalue(L,obj,x) \
+  { TValue *i_o=(obj); \
+    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TUSERDATA; \
+    checkliveness(G(L),i_o); }
+
+#define setthvalue(L,obj,x) \
+  { TValue *i_o=(obj); \
+    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTHREAD; \
+    checkliveness(G(L),i_o); }
+
+#define setclvalue(L,obj,x) \
+  { TValue *i_o=(obj); \
+    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TFUNCTION; \
+    checkliveness(G(L),i_o); }
+
+#define sethvalue(L,obj,x) \
+  { TValue *i_o=(obj); \
+    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTABLE; \
+    checkliveness(G(L),i_o); }
+
+#define setptvalue(L,obj,x) \
+  { TValue *i_o=(obj); \
+    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TPROTO; \
+    checkliveness(G(L),i_o); }
+
+
+
+
+#define setobj(L,obj1,obj2) \
+  { const TValue *o2=(obj2); TValue *o1=(obj1); \
+    o1->value = o2->value; o1->tt=o2->tt; \
+    checkliveness(G(L),o1); }
+
+
+/*
+** different types of sets, according to destination
+*/
+
+/* from stack to (same) stack */
+#define setobjs2s	setobj
+/* to stack (not from same stack) */
+#define setobj2s	setobj
+#define setsvalue2s	setsvalue
+#define sethvalue2s	sethvalue
+#define setptvalue2s	setptvalue
+/* from table to same table */
+#define setobjt2t	setobj
+/* to table */
+#define setobj2t	setobj
+/* to new object */
+#define setobj2n	setobj
+#define setsvalue2n	setsvalue
+
+#define setttype(obj, tt) (ttype(obj) = (tt))
+
+
+#define iscollectable(o)	(ttype(o) >= LUA_TSTRING)
+
+
+
+typedef TValue *StkId;  /* index to stack elements */
+
+
+/*
+** String headers for string table
+*/
+typedef union TString {
+  L_Umaxalign dummy;  /* ensures maximum alignment for strings */
+  struct {
+    CommonHeader;
+    lu_byte reserved;
+    unsigned int hash;
+    size_t len;
+  } tsv;
+} TString;
+
+
+#define getstr(ts)	cast(const char *, (ts) + 1)
+#define svalue(o)       getstr(rawtsvalue(o))
+
+
+
+typedef union Udata {
+  L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */
+  struct {
+    CommonHeader;
+    struct Table *metatable;
+    struct Table *env;
+    size_t len;
+  } uv;
+} Udata;
+
+
+
+
+/*
+** Function Prototypes
+*/
+typedef struct Proto {
+  CommonHeader;
+  TValue *k;  /* constants used by the function */
+  Instruction *code;
+  struct Proto **p;  /* functions defined inside the function */
+  int *lineinfo;  /* map from opcodes to source lines */
+  struct LocVar *locvars;  /* information about local variables */
+  TString **upvalues;  /* upvalue names */
+  TString  *source;
+  int sizeupvalues;
+  int sizek;  /* size of `k' */
+  int sizecode;
+  int sizelineinfo;
+  int sizep;  /* size of `p' */
+  int sizelocvars;
+  int linedefined;
+  int lastlinedefined;
+  GCObject *gclist;
+  lu_byte nups;  /* number of upvalues */
+  lu_byte numparams;
+  lu_byte is_vararg;
+  lu_byte maxstacksize;
+} Proto;
+
+
+/* masks for new-style vararg */
+#define VARARG_HASARG		1
+#define VARARG_ISVARARG		2
+#define VARARG_NEEDSARG		4
+
+
+typedef struct LocVar {
+  TString *varname;
+  int startpc;  /* first point where variable is active */
+  int endpc;    /* first point where variable is dead */
+} LocVar;
+
+
+
+/*
+** Upvalues
+*/
+
+typedef struct UpVal {
+  CommonHeader;
+  TValue *v;  /* points to stack or to its own value */
+  union {
+    TValue value;  /* the value (when closed) */
+    struct {  /* double linked list (when open) */
+      struct UpVal *prev;
+      struct UpVal *next;
+    } l;
+  } u;
+} UpVal;
+
+
+/*
+** Closures
+*/
+
+#define ClosureHeader \
+	CommonHeader; lu_byte isC; lu_byte nupvalues; GCObject *gclist; \
+	struct Table *env
+
+typedef struct CClosure {
+  ClosureHeader;
+  lua_CFunction f;
+  TValue upvalue[1];
+} CClosure;
+
+
+typedef struct LClosure {
+  ClosureHeader;
+  struct Proto *p;
+  UpVal *upvals[1];
+} LClosure;
+
+
+typedef union Closure {
+  CClosure c;
+  LClosure l;
+} Closure;
+
+
+#define iscfunction(o)	(ttype(o) == LUA_TFUNCTION && clvalue(o)->c.isC)
+#define isLfunction(o)	(ttype(o) == LUA_TFUNCTION && !clvalue(o)->c.isC)
+
+
+/*
+** Tables
+*/
+
+typedef union TKey {
+  struct {
+    TValuefields;
+    struct Node *next;  /* for chaining */
+  } nk;
+  TValue tvk;
+} TKey;
+
+
+typedef struct Node {
+  TValue i_val;
+  TKey i_key;
+} Node;
+
+
+typedef struct Table {
+  CommonHeader;
+  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */ 
+  lu_byte lsizenode;  /* log2 of size of `node' array */
+  struct Table *metatable;
+  TValue *array;  /* array part */
+  Node *node;
+  Node *lastfree;  /* any free position is before this position */
+  GCObject *gclist;
+  int sizearray;  /* size of `array' array */
+} Table;
+
+
+
+/*
+** `module' operation for hashing (size is always a power of 2)
+*/
+#define lmod(s,size) \
+	(check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1)))))
+
+
+#define twoto(x)	(1<<(x))
+#define sizenode(t)	(twoto((t)->lsizenode))
+
+
+#define luaO_nilobject		(&luaO_nilobject_)
+
+LUAI_DATA const TValue luaO_nilobject_;
+
+#define ceillog2(x)	(luaO_log2((x)-1) + 1)
+
+LUAI_FUNC int luaO_log2 (unsigned int x);
+LUAI_FUNC int luaO_int2fb (unsigned int x);
+LUAI_FUNC int luaO_fb2int (int x);
+LUAI_FUNC int luaO_rawequalObj (const TValue *t1, const TValue *t2);
+LUAI_FUNC int luaO_str2d (const char *s, lua_Number *result);
+LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
+                                                       va_list argp);
+LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
+LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);
+
+
+#endif
+
diff --git a/third_party/lua-src/lua-5.1.5/lopcodes.c b/third_party/lua-src/lua-5.1.5/lopcodes.c
new file mode 100644
index 00000000..4cc74523
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lopcodes.c
@@ -0,0 +1,102 @@
+/*
+** $Id: lopcodes.c,v 1.37.1.1 2007/12/27 13:02:25 roberto Exp $
+** See Copyright Notice in lua.h
+*/
+
+
+#define lopcodes_c
+#define LUA_CORE
+
+
+#include "lopcodes.h"
+
+
+/* ORDER OP */
+
+const char *const luaP_opnames[NUM_OPCODES+1] = {
+  "MOVE",
+  "LOADK",
+  "LOADBOOL",
+  "LOADNIL",
+  "GETUPVAL",
+  "GETGLOBAL",
+  "GETTABLE",
+  "SETGLOBAL",
+  "SETUPVAL",
+  "SETTABLE",
+  "NEWTABLE",
+  "SELF",
+  "ADD",
+  "SUB",
+  "MUL",
+  "DIV",
+  "MOD",
+  "POW",
+  "UNM",
+  "NOT",
+  "LEN",
+  "CONCAT",
+  "JMP",
+  "EQ",
+  "LT",
+  "LE",
+  "TEST",
+  "TESTSET",
+  "CALL",
+  "TAILCALL",
+  "RETURN",
+  "FORLOOP",
+  "FORPREP",
+  "TFORLOOP",
+  "SETLIST",
+  "CLOSE",
+  "CLOSURE",
+  "VARARG",
+  NULL
+};
+
+
+#define opmode(t,a,b,c,m) (((t)<<7) | ((a)<<6) | ((b)<<4) | ((c)<<2) | (m))
+
+const lu_byte luaP_opmodes[NUM_OPCODES] = {
+/*       T  A    B       C     mode		   opcode	*/
+  opmode(0, 1, OpArgR, OpArgN, iABC) 		/* OP_MOVE */
+ ,opmode(0, 1, OpArgK, OpArgN, iABx)		/* OP_LOADK */
+ ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_LOADBOOL */
+ ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_LOADNIL */
+ ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_GETUPVAL */
+ ,opmode(0, 1, OpArgK, OpArgN, iABx)		/* OP_GETGLOBAL */
+ ,opmode(0, 1, OpArgR, OpArgK, iABC)		/* OP_GETTABLE */
+ ,opmode(0, 0, OpArgK, OpArgN, iABx)		/* OP_SETGLOBAL */
+ ,opmode(0, 0, OpArgU, OpArgN, iABC)		/* OP_SETUPVAL */
+ ,opmode(0, 0, OpArgK, OpArgK, iABC)		/* OP_SETTABLE */
+ ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_NEWTABLE */
+ ,opmode(0, 1, OpArgR, OpArgK, iABC)		/* OP_SELF */
+ ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_ADD */
+ ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_SUB */
+ ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_MUL */
+ ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_DIV */
+ ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_MOD */
+ ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_POW */
+ ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_UNM */
+ ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_NOT */
+ ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_LEN */
+ ,opmode(0, 1, OpArgR, OpArgR, iABC)		/* OP_CONCAT */
+ ,opmode(0, 0, OpArgR, OpArgN, iAsBx)		/* OP_JMP */
+ ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_EQ */
+ ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_LT */
+ ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_LE */
+ ,opmode(1, 1, OpArgR, OpArgU, iABC)		/* OP_TEST */
+ ,opmode(1, 1, OpArgR, OpArgU, iABC)		/* OP_TESTSET */
+ ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_CALL */
+ ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_TAILCALL */
+ ,opmode(0, 0, OpArgU, OpArgN, iABC)		/* OP_RETURN */
+ ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_FORLOOP */
+ ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_FORPREP */
+ ,opmode(1, 0, OpArgN, OpArgU, iABC)		/* OP_TFORLOOP */
+ ,opmode(0, 0, OpArgU, OpArgU, iABC)		/* OP_SETLIST */
+ ,opmode(0, 0, OpArgN, OpArgN, iABC)		/* OP_CLOSE */
+ ,opmode(0, 1, OpArgU, OpArgN, iABx)		/* OP_CLOSURE */
+ ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_VARARG */
+};
+
diff --git a/third_party/lua-src/lua-5.1.5/lopcodes.h b/third_party/lua-src/lua-5.1.5/lopcodes.h
new file mode 100644
index 00000000..41224d6e
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lopcodes.h
@@ -0,0 +1,268 @@
+/*
+** $Id: lopcodes.h,v 1.125.1.1 2007/12/27 13:02:25 roberto Exp $
+** Opcodes for Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lopcodes_h
+#define lopcodes_h
+
+#include "llimits.h"
+
+
+/*===========================================================================
+  We assume that instructions are unsigned numbers.
+  All instructions have an opcode in the first 6 bits.
+  Instructions can have the following fields:
+	`A' : 8 bits
+	`B' : 9 bits
+	`C' : 9 bits
+	`Bx' : 18 bits (`B' and `C' together)
+	`sBx' : signed Bx
+
+  A signed argument is represented in excess K; that is, the number
+  value is the unsigned value minus K. K is exactly the maximum value
+  for that argument (so that -max is represented by 0, and +max is
+  represented by 2*max), which is half the maximum for the corresponding
+  unsigned argument.
+===========================================================================*/
+
+
+enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
+
+
+/*
+** size and position of opcode arguments.
+*/
+#define SIZE_C		9
+#define SIZE_B		9
+#define SIZE_Bx		(SIZE_C + SIZE_B)
+#define SIZE_A		8
+
+#define SIZE_OP		6
+
+#define POS_OP		0
+#define POS_A		(POS_OP + SIZE_OP)
+#define POS_C		(POS_A + SIZE_A)
+#define POS_B		(POS_C + SIZE_C)
+#define POS_Bx		POS_C
+
+
+/*
+** limits for opcode arguments.
+** we use (signed) int to manipulate most arguments,
+** so they must fit in LUAI_BITSINT-1 bits (-1 for sign)
+*/
+#if SIZE_Bx < LUAI_BITSINT-1
+#define MAXARG_Bx        ((1<<SIZE_Bx)-1)
+#define MAXARG_sBx        (MAXARG_Bx>>1)         /* `sBx' is signed */
+#else
+#define MAXARG_Bx        MAX_INT
+#define MAXARG_sBx        MAX_INT
+#endif
+
+
+#define MAXARG_A        ((1<<SIZE_A)-1)
+#define MAXARG_B        ((1<<SIZE_B)-1)
+#define MAXARG_C        ((1<<SIZE_C)-1)
+
+
+/* creates a mask with `n' 1 bits at position `p' */
+#define MASK1(n,p)	((~((~(Instruction)0)<<n))<<p)
+
+/* creates a mask with `n' 0 bits at position `p' */
+#define MASK0(n,p)	(~MASK1(n,p))
+
+/*
+** the following macros help to manipulate instructions
+*/
+
+#define GET_OPCODE(i)	(cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0)))
+#define SET_OPCODE(i,o)	((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \
+		((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
+
+#define GETARG_A(i)	(cast(int, ((i)>>POS_A) & MASK1(SIZE_A,0)))
+#define SETARG_A(i,u)	((i) = (((i)&MASK0(SIZE_A,POS_A)) | \
+		((cast(Instruction, u)<<POS_A)&MASK1(SIZE_A,POS_A))))
+
+#define GETARG_B(i)	(cast(int, ((i)>>POS_B) & MASK1(SIZE_B,0)))
+#define SETARG_B(i,b)	((i) = (((i)&MASK0(SIZE_B,POS_B)) | \
+		((cast(Instruction, b)<<POS_B)&MASK1(SIZE_B,POS_B))))
+
+#define GETARG_C(i)	(cast(int, ((i)>>POS_C) & MASK1(SIZE_C,0)))
+#define SETARG_C(i,b)	((i) = (((i)&MASK0(SIZE_C,POS_C)) | \
+		((cast(Instruction, b)<<POS_C)&MASK1(SIZE_C,POS_C))))
+
+#define GETARG_Bx(i)	(cast(int, ((i)>>POS_Bx) & MASK1(SIZE_Bx,0)))
+#define SETARG_Bx(i,b)	((i) = (((i)&MASK0(SIZE_Bx,POS_Bx)) | \
+		((cast(Instruction, b)<<POS_Bx)&MASK1(SIZE_Bx,POS_Bx))))
+
+#define GETARG_sBx(i)	(GETARG_Bx(i)-MAXARG_sBx)
+#define SETARG_sBx(i,b)	SETARG_Bx((i),cast(unsigned int, (b)+MAXARG_sBx))
+
+
+#define CREATE_ABC(o,a,b,c)	((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_A) \
+			| (cast(Instruction, b)<<POS_B) \
+			| (cast(Instruction, c)<<POS_C))
+
+#define CREATE_ABx(o,a,bc)	((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_A) \
+			| (cast(Instruction, bc)<<POS_Bx))
+
+
+/*
+** Macros to operate RK indices
+*/
+
+/* this bit 1 means constant (0 means register) */
+#define BITRK		(1 << (SIZE_B - 1))
+
+/* test whether value is a constant */
+#define ISK(x)		((x) & BITRK)
+
+/* gets the index of the constant */
+#define INDEXK(r)	((int)(r) & ~BITRK)
+
+#define MAXINDEXRK	(BITRK - 1)
+
+/* code a constant index as a RK value */
+#define RKASK(x)	((x) | BITRK)
+
+
+/*
+** invalid register that fits in 8 bits
+*/
+#define NO_REG		MAXARG_A
+
+
+/*
+** R(x) - register
+** Kst(x) - constant (in constant table)
+** RK(x) == if ISK(x) then Kst(INDEXK(x)) else R(x)
+*/
+
+
+/*
+** grep "ORDER OP" if you change these enums
+*/
+
+typedef enum {
+/*----------------------------------------------------------------------
+name		args	description
+------------------------------------------------------------------------*/
+OP_MOVE,/*	A B	R(A) := R(B)					*/
+OP_LOADK,/*	A Bx	R(A) := Kst(Bx)					*/
+OP_LOADBOOL,/*	A B C	R(A) := (Bool)B; if (C) pc++			*/
+OP_LOADNIL,/*	A B	R(A) := ... := R(B) := nil			*/
+OP_GETUPVAL,/*	A B	R(A) := UpValue[B]				*/
+
+OP_GETGLOBAL,/*	A Bx	R(A) := Gbl[Kst(Bx)]				*/
+OP_GETTABLE,/*	A B C	R(A) := R(B)[RK(C)]				*/
+
+OP_SETGLOBAL,/*	A Bx	Gbl[Kst(Bx)] := R(A)				*/
+OP_SETUPVAL,/*	A B	UpValue[B] := R(A)				*/
+OP_SETTABLE,/*	A B C	R(A)[RK(B)] := RK(C)				*/
+
+OP_NEWTABLE,/*	A B C	R(A) := {} (size = B,C)				*/
+
+OP_SELF,/*	A B C	R(A+1) := R(B); R(A) := R(B)[RK(C)]		*/
+
+OP_ADD,/*	A B C	R(A) := RK(B) + RK(C)				*/
+OP_SUB,/*	A B C	R(A) := RK(B) - RK(C)				*/
+OP_MUL,/*	A B C	R(A) := RK(B) * RK(C)				*/
+OP_DIV,/*	A B C	R(A) := RK(B) / RK(C)				*/
+OP_MOD,/*	A B C	R(A) := RK(B) % RK(C)				*/
+OP_POW,/*	A B C	R(A) := RK(B) ^ RK(C)				*/
+OP_UNM,/*	A B	R(A) := -R(B)					*/
+OP_NOT,/*	A B	R(A) := not R(B)				*/
+OP_LEN,/*	A B	R(A) := length of R(B)				*/
+
+OP_CONCAT,/*	A B C	R(A) := R(B).. ... ..R(C)			*/
+
+OP_JMP,/*	sBx	pc+=sBx					*/
+
+OP_EQ,/*	A B C	if ((RK(B) == RK(C)) ~= A) then pc++		*/
+OP_LT,/*	A B C	if ((RK(B) <  RK(C)) ~= A) then pc++  		*/
+OP_LE,/*	A B C	if ((RK(B) <= RK(C)) ~= A) then pc++  		*/
+
+OP_TEST,/*	A C	if not (R(A) <=> C) then pc++			*/ 
+OP_TESTSET,/*	A B C	if (R(B) <=> C) then R(A) := R(B) else pc++	*/ 
+
+OP_CALL,/*	A B C	R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */
+OP_TAILCALL,/*	A B C	return R(A)(R(A+1), ... ,R(A+B-1))		*/
+OP_RETURN,/*	A B	return R(A), ... ,R(A+B-2)	(see note)	*/
+
+OP_FORLOOP,/*	A sBx	R(A)+=R(A+2);
+			if R(A) <?= R(A+1) then { pc+=sBx; R(A+3)=R(A) }*/
+OP_FORPREP,/*	A sBx	R(A)-=R(A+2); pc+=sBx				*/
+
+OP_TFORLOOP,/*	A C	R(A+3), ... ,R(A+2+C) := R(A)(R(A+1), R(A+2)); 
+                        if R(A+3) ~= nil then R(A+2)=R(A+3) else pc++	*/ 
+OP_SETLIST,/*	A B C	R(A)[(C-1)*FPF+i] := R(A+i), 1 <= i <= B	*/
+
+OP_CLOSE,/*	A 	close all variables in the stack up to (>=) R(A)*/
+OP_CLOSURE,/*	A Bx	R(A) := closure(KPROTO[Bx], R(A), ... ,R(A+n))	*/
+
+OP_VARARG/*	A B	R(A), R(A+1), ..., R(A+B-1) = vararg		*/
+} OpCode;
+
+
+#define NUM_OPCODES	(cast(int, OP_VARARG) + 1)
+
+
+
+/*===========================================================================
+  Notes:
+  (*) In OP_CALL, if (B == 0) then B = top. C is the number of returns - 1,
+      and can be 0: OP_CALL then sets `top' to last_result+1, so
+      next open instruction (OP_CALL, OP_RETURN, OP_SETLIST) may use `top'.
+
+  (*) In OP_VARARG, if (B == 0) then use actual number of varargs and
+      set top (like in OP_CALL with C == 0).
+
+  (*) In OP_RETURN, if (B == 0) then return up to `top'
+
+  (*) In OP_SETLIST, if (B == 0) then B = `top';
+      if (C == 0) then next `instruction' is real C
+
+  (*) For comparisons, A specifies what condition the test should accept
+      (true or false).
+
+  (*) All `skips' (pc++) assume that next instruction is a jump
+===========================================================================*/
+
+
+/*
+** masks for instruction properties. The format is:
+** bits 0-1: op mode
+** bits 2-3: C arg mode
+** bits 4-5: B arg mode
+** bit 6: instruction set register A
+** bit 7: operator is a test
+*/  
+
+enum OpArgMask {
+  OpArgN,  /* argument is not used */
+  OpArgU,  /* argument is used */
+  OpArgR,  /* argument is a register or a jump offset */
+  OpArgK   /* argument is a constant or register/constant */
+};
+
+LUAI_DATA const lu_byte luaP_opmodes[NUM_OPCODES];
+
+#define getOpMode(m)	(cast(enum OpMode, luaP_opmodes[m] & 3))
+#define getBMode(m)	(cast(enum OpArgMask, (luaP_opmodes[m] >> 4) & 3))
+#define getCMode(m)	(cast(enum OpArgMask, (luaP_opmodes[m] >> 2) & 3))
+#define testAMode(m)	(luaP_opmodes[m] & (1 << 6))
+#define testTMode(m)	(luaP_opmodes[m] & (1 << 7))
+
+
+LUAI_DATA const char *const luaP_opnames[NUM_OPCODES+1];  /* opcode names */
+
+
+/* number of list items to accumulate before a SETLIST instruction */
+#define LFIELDS_PER_FLUSH	50
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/loslib.c b/third_party/lua-src/lua-5.1.5/loslib.c
new file mode 100644
index 00000000..2a41a248
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/loslib.c
@@ -0,0 +1,255 @@
+/*
+** $Id: loslib.c,v 1.19.1.3 2008/01/18 16:38:18 roberto Exp $
+** Standard Operating System library
+** See Copyright Notice in lua.h
+*/
+
+
+#include <errno.h>
+#include <locale.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#define loslib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+static int os_pushresult (lua_State *L, int i, const char *filename) {
+  int en = errno;  /* calls to Lua API may change this value */
+  if (i) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);
+    lua_pushfstring(L, "%s: %s", filename, strerror(en));
+    lua_pushinteger(L, en);
+    return 3;
+  }
+}
+
+
+static int os_execute (lua_State *L) {
+#if !defined(__wasi__)
+  lua_pushinteger(L, system(luaL_optstring(L, 1, NULL)));
+  return 1;
+#else
+  luaL_error(L, "not supported on WASI");
+#endif
+}
+
+
+static int os_remove (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  return os_pushresult(L, remove(filename) == 0, filename);
+}
+
+
+static int os_rename (lua_State *L) {
+  const char *fromname = luaL_checkstring(L, 1);
+  const char *toname = luaL_checkstring(L, 2);
+  return os_pushresult(L, rename(fromname, toname) == 0, fromname);
+}
+
+
+static int os_tmpname (lua_State *L) {
+#if !defined(__wasi__)
+  char buff[LUA_TMPNAMBUFSIZE];
+  int err;
+  lua_tmpnam(buff, err);
+  if (err)
+    return luaL_error(L, "unable to generate a unique filename");
+  lua_pushstring(L, buff);
+  return 1;
+#else
+  luaL_error(L, "not supported on WASI");
+#endif
+}
+
+
+static int os_getenv (lua_State *L) {
+  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
+  return 1;
+}
+
+
+static int os_clock (lua_State *L) {
+#if !defined(__wasi__)
+  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
+  return 1;
+#else
+  luaL_error(L, "not supported on WASI");
+#endif
+}
+
+
+/*
+** {======================================================
+** Time/Date operations
+** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
+**   wday=%w+1, yday=%j, isdst=? }
+** =======================================================
+*/
+
+static void setfield (lua_State *L, const char *key, int value) {
+  lua_pushinteger(L, value);
+  lua_setfield(L, -2, key);
+}
+
+static void setboolfield (lua_State *L, const char *key, int value) {
+  if (value < 0)  /* undefined? */
+    return;  /* does not set field */
+  lua_pushboolean(L, value);
+  lua_setfield(L, -2, key);
+}
+
+static int getboolfield (lua_State *L, const char *key) {
+  int res;
+  lua_getfield(L, -1, key);
+  res = lua_isnil(L, -1) ? -1 : lua_toboolean(L, -1);
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int getfield (lua_State *L, const char *key, int d) {
+  int res;
+  lua_getfield(L, -1, key);
+  if (lua_isnumber(L, -1))
+    res = (int)lua_tointeger(L, -1);
+  else {
+    if (d < 0)
+      return luaL_error(L, "field " LUA_QS " missing in date table", key);
+    res = d;
+  }
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int os_date (lua_State *L) {
+  const char *s = luaL_optstring(L, 1, "%c");
+  time_t t = luaL_opt(L, (time_t)luaL_checknumber, 2, time(NULL));
+  struct tm *stm;
+  if (*s == '!') {  /* UTC? */
+    stm = gmtime(&t);
+    s++;  /* skip `!' */
+  }
+  else
+    stm = localtime(&t);
+  if (stm == NULL)  /* invalid date? */
+    lua_pushnil(L);
+  else if (strcmp(s, "*t") == 0) {
+    lua_createtable(L, 0, 9);  /* 9 = number of fields */
+    setfield(L, "sec", stm->tm_sec);
+    setfield(L, "min", stm->tm_min);
+    setfield(L, "hour", stm->tm_hour);
+    setfield(L, "day", stm->tm_mday);
+    setfield(L, "month", stm->tm_mon+1);
+    setfield(L, "year", stm->tm_year+1900);
+    setfield(L, "wday", stm->tm_wday+1);
+    setfield(L, "yday", stm->tm_yday+1);
+    setboolfield(L, "isdst", stm->tm_isdst);
+  }
+  else {
+    char cc[3];
+    luaL_Buffer b;
+    cc[0] = '%'; cc[2] = '\0';
+    luaL_buffinit(L, &b);
+    for (; *s; s++) {
+      if (*s != '%' || *(s + 1) == '\0')  /* no conversion specifier? */
+        luaL_addchar(&b, *s);
+      else {
+        size_t reslen;
+        char buff[200];  /* should be big enough for any conversion result */
+        cc[1] = *(++s);
+        reslen = strftime(buff, sizeof(buff), cc, stm);
+        luaL_addlstring(&b, buff, reslen);
+      }
+    }
+    luaL_pushresult(&b);
+  }
+  return 1;
+}
+
+
+static int os_time (lua_State *L) {
+  time_t t;
+  if (lua_isnoneornil(L, 1))  /* called without args? */
+    t = time(NULL);  /* get current time */
+  else {
+    struct tm ts;
+    luaL_checktype(L, 1, LUA_TTABLE);
+    lua_settop(L, 1);  /* make sure table is at the top */
+    ts.tm_sec = getfield(L, "sec", 0);
+    ts.tm_min = getfield(L, "min", 0);
+    ts.tm_hour = getfield(L, "hour", 12);
+    ts.tm_mday = getfield(L, "day", -1);
+    ts.tm_mon = getfield(L, "month", -1) - 1;
+    ts.tm_year = getfield(L, "year", -1) - 1900;
+    ts.tm_isdst = getboolfield(L, "isdst");
+    t = mktime(&ts);
+  }
+  if (t == (time_t)(-1))
+    lua_pushnil(L);
+  else
+    lua_pushnumber(L, (lua_Number)t);
+  return 1;
+}
+
+
+static int os_difftime (lua_State *L) {
+  lua_pushnumber(L, difftime((time_t)(luaL_checknumber(L, 1)),
+                             (time_t)(luaL_optnumber(L, 2, 0))));
+  return 1;
+}
+
+/* }====================================================== */
+
+
+static int os_setlocale (lua_State *L) {
+  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
+                      LC_NUMERIC, LC_TIME};
+  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
+     "numeric", "time", NULL};
+  const char *l = luaL_optstring(L, 1, NULL);
+  int op = luaL_checkoption(L, 2, "all", catnames);
+  lua_pushstring(L, setlocale(cat[op], l));
+  return 1;
+}
+
+
+static int os_exit (lua_State *L) {
+  exit(luaL_optint(L, 1, EXIT_SUCCESS));
+}
+
+static const luaL_Reg syslib[] = {
+  {"clock",     os_clock},
+  {"date",      os_date},
+  {"difftime",  os_difftime},
+  {"execute",   os_execute},
+  {"exit",      os_exit},
+  {"getenv",    os_getenv},
+  {"remove",    os_remove},
+  {"rename",    os_rename},
+  {"setlocale", os_setlocale},
+  {"time",      os_time},
+  {"tmpname",   os_tmpname},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+
+LUALIB_API int luaopen_os (lua_State *L) {
+  luaL_register(L, LUA_OSLIBNAME, syslib);
+  return 1;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lparser.c b/third_party/lua-src/lua-5.1.5/lparser.c
new file mode 100644
index 00000000..dda7488d
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lparser.c
@@ -0,0 +1,1339 @@
+/*
+** $Id: lparser.c,v 2.42.1.4 2011/10/21 19:31:42 roberto Exp $
+** Lua Parser
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#define lparser_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+
+
+
+#define hasmultret(k)		((k) == VCALL || (k) == VVARARG)
+
+#define getlocvar(fs, i)	((fs)->f->locvars[(fs)->actvar[i]])
+
+#define luaY_checklimit(fs,v,l,m)	if ((v)>(l)) errorlimit(fs,l,m)
+
+
+/*
+** nodes for block list (list of active blocks)
+*/
+typedef struct BlockCnt {
+  struct BlockCnt *previous;  /* chain */
+  int breaklist;  /* list of jumps out of this loop */
+  lu_byte nactvar;  /* # active locals outside the breakable structure */
+  lu_byte upval;  /* true if some variable in the block is an upvalue */
+  lu_byte isbreakable;  /* true if `block' is a loop */
+} BlockCnt;
+
+
+
+/*
+** prototypes for recursive non-terminal functions
+*/
+static void chunk (LexState *ls);
+static void expr (LexState *ls, expdesc *v);
+
+
+static void anchor_token (LexState *ls) {
+  if (ls->t.token == TK_NAME || ls->t.token == TK_STRING) {
+    TString *ts = ls->t.seminfo.ts;
+    luaX_newstring(ls, getstr(ts), ts->tsv.len);
+  }
+}
+
+
+static void error_expected (LexState *ls, int token) {
+  luaX_syntaxerror(ls,
+      luaO_pushfstring(ls->L, LUA_QS " expected", luaX_token2str(ls, token)));
+}
+
+
+static void errorlimit (FuncState *fs, int limit, const char *what) {
+  const char *msg = (fs->f->linedefined == 0) ?
+    luaO_pushfstring(fs->L, "main function has more than %d %s", limit, what) :
+    luaO_pushfstring(fs->L, "function at line %d has more than %d %s",
+                            fs->f->linedefined, limit, what);
+  luaX_lexerror(fs->ls, msg, 0);
+}
+
+
+static int testnext (LexState *ls, int c) {
+  if (ls->t.token == c) {
+    luaX_next(ls);
+    return 1;
+  }
+  else return 0;
+}
+
+
+static void check (LexState *ls, int c) {
+  if (ls->t.token != c)
+    error_expected(ls, c);
+}
+
+static void checknext (LexState *ls, int c) {
+  check(ls, c);
+  luaX_next(ls);
+}
+
+
+#define check_condition(ls,c,msg)	{ if (!(c)) luaX_syntaxerror(ls, msg); }
+
+
+
+static void check_match (LexState *ls, int what, int who, int where) {
+  if (!testnext(ls, what)) {
+    if (where == ls->linenumber)
+      error_expected(ls, what);
+    else {
+      luaX_syntaxerror(ls, luaO_pushfstring(ls->L,
+             LUA_QS " expected (to close " LUA_QS " at line %d)",
+              luaX_token2str(ls, what), luaX_token2str(ls, who), where));
+    }
+  }
+}
+
+
+static TString *str_checkname (LexState *ls) {
+  TString *ts;
+  check(ls, TK_NAME);
+  ts = ls->t.seminfo.ts;
+  luaX_next(ls);
+  return ts;
+}
+
+
+static void init_exp (expdesc *e, expkind k, int i) {
+  e->f = e->t = NO_JUMP;
+  e->k = k;
+  e->u.s.info = i;
+}
+
+
+static void codestring (LexState *ls, expdesc *e, TString *s) {
+  init_exp(e, VK, luaK_stringK(ls->fs, s));
+}
+
+
+static void checkname(LexState *ls, expdesc *e) {
+  codestring(ls, e, str_checkname(ls));
+}
+
+
+static int registerlocalvar (LexState *ls, TString *varname) {
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;
+  int oldsize = f->sizelocvars;
+  luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
+                  LocVar, SHRT_MAX, "too many local variables");
+  while (oldsize < f->sizelocvars) f->locvars[oldsize++].varname = NULL;
+  f->locvars[fs->nlocvars].varname = varname;
+  luaC_objbarrier(ls->L, f, varname);
+  return fs->nlocvars++;
+}
+
+
+#define new_localvarliteral(ls,v,n) \
+  new_localvar(ls, luaX_newstring(ls, "" v, (sizeof(v)/sizeof(char))-1), n)
+
+
+static void new_localvar (LexState *ls, TString *name, int n) {
+  FuncState *fs = ls->fs;
+  luaY_checklimit(fs, fs->nactvar+n+1, LUAI_MAXVARS, "local variables");
+  fs->actvar[fs->nactvar+n] = cast(unsigned short, registerlocalvar(ls, name));
+}
+
+
+static void adjustlocalvars (LexState *ls, int nvars) {
+  FuncState *fs = ls->fs;
+  fs->nactvar = cast_byte(fs->nactvar + nvars);
+  for (; nvars; nvars--) {
+    getlocvar(fs, fs->nactvar - nvars).startpc = fs->pc;
+  }
+}
+
+
+static void removevars (LexState *ls, int tolevel) {
+  FuncState *fs = ls->fs;
+  while (fs->nactvar > tolevel)
+    getlocvar(fs, --fs->nactvar).endpc = fs->pc;
+}
+
+
+static int indexupvalue (FuncState *fs, TString *name, expdesc *v) {
+  int i;
+  Proto *f = fs->f;
+  int oldsize = f->sizeupvalues;
+  for (i=0; i<f->nups; i++) {
+    if (fs->upvalues[i].k == v->k && fs->upvalues[i].info == v->u.s.info) {
+      lua_assert(f->upvalues[i] == name);
+      return i;
+    }
+  }
+  /* new one */
+  luaY_checklimit(fs, f->nups + 1, LUAI_MAXUPVALUES, "upvalues");
+  luaM_growvector(fs->L, f->upvalues, f->nups, f->sizeupvalues,
+                  TString *, MAX_INT, "");
+  while (oldsize < f->sizeupvalues) f->upvalues[oldsize++] = NULL;
+  f->upvalues[f->nups] = name;
+  luaC_objbarrier(fs->L, f, name);
+  lua_assert(v->k == VLOCAL || v->k == VUPVAL);
+  fs->upvalues[f->nups].k = cast_byte(v->k);
+  fs->upvalues[f->nups].info = cast_byte(v->u.s.info);
+  return f->nups++;
+}
+
+
+static int searchvar (FuncState *fs, TString *n) {
+  int i;
+  for (i=fs->nactvar-1; i >= 0; i--) {
+    if (n == getlocvar(fs, i).varname)
+      return i;
+  }
+  return -1;  /* not found */
+}
+
+
+static void markupval (FuncState *fs, int level) {
+  BlockCnt *bl = fs->bl;
+  while (bl && bl->nactvar > level) bl = bl->previous;
+  if (bl) bl->upval = 1;
+}
+
+
+static int singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
+  if (fs == NULL) {  /* no more levels? */
+    init_exp(var, VGLOBAL, NO_REG);  /* default is global variable */
+    return VGLOBAL;
+  }
+  else {
+    int v = searchvar(fs, n);  /* look up at current level */
+    if (v >= 0) {
+      init_exp(var, VLOCAL, v);
+      if (!base)
+        markupval(fs, v);  /* local will be used as an upval */
+      return VLOCAL;
+    }
+    else {  /* not found at current level; try upper one */
+      if (singlevaraux(fs->prev, n, var, 0) == VGLOBAL)
+        return VGLOBAL;
+      var->u.s.info = indexupvalue(fs, n, var);  /* else was LOCAL or UPVAL */
+      var->k = VUPVAL;  /* upvalue in this level */
+      return VUPVAL;
+    }
+  }
+}
+
+
+static void singlevar (LexState *ls, expdesc *var) {
+  TString *varname = str_checkname(ls);
+  FuncState *fs = ls->fs;
+  if (singlevaraux(fs, varname, var, 1) == VGLOBAL)
+    var->u.s.info = luaK_stringK(fs, varname);  /* info points to global name */
+}
+
+
+static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) {
+  FuncState *fs = ls->fs;
+  int extra = nvars - nexps;
+  if (hasmultret(e->k)) {
+    extra++;  /* includes call itself */
+    if (extra < 0) extra = 0;
+    luaK_setreturns(fs, e, extra);  /* last exp. provides the difference */
+    if (extra > 1) luaK_reserveregs(fs, extra-1);
+  }
+  else {
+    if (e->k != VVOID) luaK_exp2nextreg(fs, e);  /* close last expression */
+    if (extra > 0) {
+      int reg = fs->freereg;
+      luaK_reserveregs(fs, extra);
+      luaK_nil(fs, reg, extra);
+    }
+  }
+}
+
+
+static void enterlevel (LexState *ls) {
+  if (++ls->L->nCcalls > LUAI_MAXCCALLS)
+	luaX_lexerror(ls, "chunk has too many syntax levels", 0);
+}
+
+
+#define leavelevel(ls)	((ls)->L->nCcalls--)
+
+
+static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isbreakable) {
+  bl->breaklist = NO_JUMP;
+  bl->isbreakable = isbreakable;
+  bl->nactvar = fs->nactvar;
+  bl->upval = 0;
+  bl->previous = fs->bl;
+  fs->bl = bl;
+  lua_assert(fs->freereg == fs->nactvar);
+}
+
+
+static void leaveblock (FuncState *fs) {
+  BlockCnt *bl = fs->bl;
+  fs->bl = bl->previous;
+  removevars(fs->ls, bl->nactvar);
+  if (bl->upval)
+    luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
+  /* a block either controls scope or breaks (never both) */
+  lua_assert(!bl->isbreakable || !bl->upval);
+  lua_assert(bl->nactvar == fs->nactvar);
+  fs->freereg = fs->nactvar;  /* free registers */
+  luaK_patchtohere(fs, bl->breaklist);
+}
+
+
+static void pushclosure (LexState *ls, FuncState *func, expdesc *v) {
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;
+  int oldsize = f->sizep;
+  int i;
+  luaM_growvector(ls->L, f->p, fs->np, f->sizep, Proto *,
+                  MAXARG_Bx, "constant table overflow");
+  while (oldsize < f->sizep) f->p[oldsize++] = NULL;
+  f->p[fs->np++] = func->f;
+  luaC_objbarrier(ls->L, f, func->f);
+  init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np-1));
+  for (i=0; i<func->f->nups; i++) {
+    OpCode o = (func->upvalues[i].k == VLOCAL) ? OP_MOVE : OP_GETUPVAL;
+    luaK_codeABC(fs, o, 0, func->upvalues[i].info, 0);
+  }
+}
+
+
+static void open_func (LexState *ls, FuncState *fs) {
+  lua_State *L = ls->L;
+  Proto *f = luaF_newproto(L);
+  fs->f = f;
+  fs->prev = ls->fs;  /* linked list of funcstates */
+  fs->ls = ls;
+  fs->L = L;
+  ls->fs = fs;
+  fs->pc = 0;
+  fs->lasttarget = -1;
+  fs->jpc = NO_JUMP;
+  fs->freereg = 0;
+  fs->nk = 0;
+  fs->np = 0;
+  fs->nlocvars = 0;
+  fs->nactvar = 0;
+  fs->bl = NULL;
+  f->source = ls->source;
+  f->maxstacksize = 2;  /* registers 0/1 are always valid */
+  fs->h = luaH_new(L, 0, 0);
+  /* anchor table of constants and prototype (to avoid being collected) */
+  sethvalue2s(L, L->top, fs->h);
+  incr_top(L);
+  setptvalue2s(L, L->top, f);
+  incr_top(L);
+}
+
+
+static void close_func (LexState *ls) {
+  lua_State *L = ls->L;
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;
+  removevars(ls, 0);
+  luaK_ret(fs, 0, 0);  /* final return */
+  luaM_reallocvector(L, f->code, f->sizecode, fs->pc, Instruction);
+  f->sizecode = fs->pc;
+  luaM_reallocvector(L, f->lineinfo, f->sizelineinfo, fs->pc, int);
+  f->sizelineinfo = fs->pc;
+  luaM_reallocvector(L, f->k, f->sizek, fs->nk, TValue);
+  f->sizek = fs->nk;
+  luaM_reallocvector(L, f->p, f->sizep, fs->np, Proto *);
+  f->sizep = fs->np;
+  luaM_reallocvector(L, f->locvars, f->sizelocvars, fs->nlocvars, LocVar);
+  f->sizelocvars = fs->nlocvars;
+  luaM_reallocvector(L, f->upvalues, f->sizeupvalues, f->nups, TString *);
+  f->sizeupvalues = f->nups;
+  lua_assert(luaG_checkcode(f));
+  lua_assert(fs->bl == NULL);
+  ls->fs = fs->prev;
+  /* last token read was anchored in defunct function; must reanchor it */
+  if (fs) anchor_token(ls);
+  L->top -= 2;  /* remove table and prototype from the stack */
+}
+
+
+Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, const char *name) {
+  struct LexState lexstate;
+  struct FuncState funcstate;
+  lexstate.buff = buff;
+  luaX_setinput(L, &lexstate, z, luaS_new(L, name));
+  open_func(&lexstate, &funcstate);
+  funcstate.f->is_vararg = VARARG_ISVARARG;  /* main func. is always vararg */
+  luaX_next(&lexstate);  /* read first token */
+  chunk(&lexstate);
+  check(&lexstate, TK_EOS);
+  close_func(&lexstate);
+  lua_assert(funcstate.prev == NULL);
+  lua_assert(funcstate.f->nups == 0);
+  lua_assert(lexstate.fs == NULL);
+  return funcstate.f;
+}
+
+
+
+/*============================================================*/
+/* GRAMMAR RULES */
+/*============================================================*/
+
+
+static void field (LexState *ls, expdesc *v) {
+  /* field -> ['.' | ':'] NAME */
+  FuncState *fs = ls->fs;
+  expdesc key;
+  luaK_exp2anyreg(fs, v);
+  luaX_next(ls);  /* skip the dot or colon */
+  checkname(ls, &key);
+  luaK_indexed(fs, v, &key);
+}
+
+
+static void yindex (LexState *ls, expdesc *v) {
+  /* index -> '[' expr ']' */
+  luaX_next(ls);  /* skip the '[' */
+  expr(ls, v);
+  luaK_exp2val(ls->fs, v);
+  checknext(ls, ']');
+}
+
+
+/*
+** {======================================================================
+** Rules for Constructors
+** =======================================================================
+*/
+
+
+struct ConsControl {
+  expdesc v;  /* last list item read */
+  expdesc *t;  /* table descriptor */
+  int nh;  /* total number of `record' elements */
+  int na;  /* total number of array elements */
+  int tostore;  /* number of array elements pending to be stored */
+};
+
+
+static void recfield (LexState *ls, struct ConsControl *cc) {
+  /* recfield -> (NAME | `['exp1`]') = exp1 */
+  FuncState *fs = ls->fs;
+  int reg = ls->fs->freereg;
+  expdesc key, val;
+  int rkkey;
+  if (ls->t.token == TK_NAME) {
+    luaY_checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
+    checkname(ls, &key);
+  }
+  else  /* ls->t.token == '[' */
+    yindex(ls, &key);
+  cc->nh++;
+  checknext(ls, '=');
+  rkkey = luaK_exp2RK(fs, &key);
+  expr(ls, &val);
+  luaK_codeABC(fs, OP_SETTABLE, cc->t->u.s.info, rkkey, luaK_exp2RK(fs, &val));
+  fs->freereg = reg;  /* free registers */
+}
+
+
+static void closelistfield (FuncState *fs, struct ConsControl *cc) {
+  if (cc->v.k == VVOID) return;  /* there is no list item */
+  luaK_exp2nextreg(fs, &cc->v);
+  cc->v.k = VVOID;
+  if (cc->tostore == LFIELDS_PER_FLUSH) {
+    luaK_setlist(fs, cc->t->u.s.info, cc->na, cc->tostore);  /* flush */
+    cc->tostore = 0;  /* no more items pending */
+  }
+}
+
+
+static void lastlistfield (FuncState *fs, struct ConsControl *cc) {
+  if (cc->tostore == 0) return;
+  if (hasmultret(cc->v.k)) {
+    luaK_setmultret(fs, &cc->v);
+    luaK_setlist(fs, cc->t->u.s.info, cc->na, LUA_MULTRET);
+    cc->na--;  /* do not count last expression (unknown number of elements) */
+  }
+  else {
+    if (cc->v.k != VVOID)
+      luaK_exp2nextreg(fs, &cc->v);
+    luaK_setlist(fs, cc->t->u.s.info, cc->na, cc->tostore);
+  }
+}
+
+
+static void listfield (LexState *ls, struct ConsControl *cc) {
+  expr(ls, &cc->v);
+  luaY_checklimit(ls->fs, cc->na, MAX_INT, "items in a constructor");
+  cc->na++;
+  cc->tostore++;
+}
+
+
+static void constructor (LexState *ls, expdesc *t) {
+  /* constructor -> ?? */
+  FuncState *fs = ls->fs;
+  int line = ls->linenumber;
+  int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
+  struct ConsControl cc;
+  cc.na = cc.nh = cc.tostore = 0;
+  cc.t = t;
+  init_exp(t, VRELOCABLE, pc);
+  init_exp(&cc.v, VVOID, 0);  /* no value (yet) */
+  luaK_exp2nextreg(ls->fs, t);  /* fix it at stack top (for gc) */
+  checknext(ls, '{');
+  do {
+    lua_assert(cc.v.k == VVOID || cc.tostore > 0);
+    if (ls->t.token == '}') break;
+    closelistfield(fs, &cc);
+    switch(ls->t.token) {
+      case TK_NAME: {  /* may be listfields or recfields */
+        luaX_lookahead(ls);
+        if (ls->lookahead.token != '=')  /* expression? */
+          listfield(ls, &cc);
+        else
+          recfield(ls, &cc);
+        break;
+      }
+      case '[': {  /* constructor_item -> recfield */
+        recfield(ls, &cc);
+        break;
+      }
+      default: {  /* constructor_part -> listfield */
+        listfield(ls, &cc);
+        break;
+      }
+    }
+  } while (testnext(ls, ',') || testnext(ls, ';'));
+  check_match(ls, '}', '{', line);
+  lastlistfield(fs, &cc);
+  SETARG_B(fs->f->code[pc], luaO_int2fb(cc.na)); /* set initial array size */
+  SETARG_C(fs->f->code[pc], luaO_int2fb(cc.nh));  /* set initial table size */
+}
+
+/* }====================================================================== */
+
+
+
+static void parlist (LexState *ls) {
+  /* parlist -> [ param { `,' param } ] */
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;
+  int nparams = 0;
+  f->is_vararg = 0;
+  if (ls->t.token != ')') {  /* is `parlist' not empty? */
+    do {
+      switch (ls->t.token) {
+        case TK_NAME: {  /* param -> NAME */
+          new_localvar(ls, str_checkname(ls), nparams++);
+          break;
+        }
+        case TK_DOTS: {  /* param -> `...' */
+          luaX_next(ls);
+#if defined(LUA_COMPAT_VARARG)
+          /* use `arg' as default name */
+          new_localvarliteral(ls, "arg", nparams++);
+          f->is_vararg = VARARG_HASARG | VARARG_NEEDSARG;
+#endif
+          f->is_vararg |= VARARG_ISVARARG;
+          break;
+        }
+        default: luaX_syntaxerror(ls, "<name> or " LUA_QL("...") " expected");
+      }
+    } while (!f->is_vararg && testnext(ls, ','));
+  }
+  adjustlocalvars(ls, nparams);
+  f->numparams = cast_byte(fs->nactvar - (f->is_vararg & VARARG_HASARG));
+  luaK_reserveregs(fs, fs->nactvar);  /* reserve register for parameters */
+}
+
+
+static void body (LexState *ls, expdesc *e, int needself, int line) {
+  /* body ->  `(' parlist `)' chunk END */
+  FuncState new_fs;
+  open_func(ls, &new_fs);
+  new_fs.f->linedefined = line;
+  checknext(ls, '(');
+  if (needself) {
+    new_localvarliteral(ls, "self", 0);
+    adjustlocalvars(ls, 1);
+  }
+  parlist(ls);
+  checknext(ls, ')');
+  chunk(ls);
+  new_fs.f->lastlinedefined = ls->linenumber;
+  check_match(ls, TK_END, TK_FUNCTION, line);
+  close_func(ls);
+  pushclosure(ls, &new_fs, e);
+}
+
+
+static int explist1 (LexState *ls, expdesc *v) {
+  /* explist1 -> expr { `,' expr } */
+  int n = 1;  /* at least one expression */
+  expr(ls, v);
+  while (testnext(ls, ',')) {
+    luaK_exp2nextreg(ls->fs, v);
+    expr(ls, v);
+    n++;
+  }
+  return n;
+}
+
+
+static void funcargs (LexState *ls, expdesc *f) {
+  FuncState *fs = ls->fs;
+  expdesc args;
+  int base, nparams;
+  int line = ls->linenumber;
+  switch (ls->t.token) {
+    case '(': {  /* funcargs -> `(' [ explist1 ] `)' */
+      if (line != ls->lastline)
+        luaX_syntaxerror(ls,"ambiguous syntax (function call x new statement)");
+      luaX_next(ls);
+      if (ls->t.token == ')')  /* arg list is empty? */
+        args.k = VVOID;
+      else {
+        explist1(ls, &args);
+        luaK_setmultret(fs, &args);
+      }
+      check_match(ls, ')', '(', line);
+      break;
+    }
+    case '{': {  /* funcargs -> constructor */
+      constructor(ls, &args);
+      break;
+    }
+    case TK_STRING: {  /* funcargs -> STRING */
+      codestring(ls, &args, ls->t.seminfo.ts);
+      luaX_next(ls);  /* must use `seminfo' before `next' */
+      break;
+    }
+    default: {
+      luaX_syntaxerror(ls, "function arguments expected");
+      return;
+    }
+  }
+  lua_assert(f->k == VNONRELOC);
+  base = f->u.s.info;  /* base register for call */
+  if (hasmultret(args.k))
+    nparams = LUA_MULTRET;  /* open call */
+  else {
+    if (args.k != VVOID)
+      luaK_exp2nextreg(fs, &args);  /* close last argument */
+    nparams = fs->freereg - (base+1);
+  }
+  init_exp(f, VCALL, luaK_codeABC(fs, OP_CALL, base, nparams+1, 2));
+  luaK_fixline(fs, line);
+  fs->freereg = base+1;  /* call remove function and arguments and leaves
+                            (unless changed) one result */
+}
+
+
+
+
+/*
+** {======================================================================
+** Expression parsing
+** =======================================================================
+*/
+
+
+static void prefixexp (LexState *ls, expdesc *v) {
+  /* prefixexp -> NAME | '(' expr ')' */
+  switch (ls->t.token) {
+    case '(': {
+      int line = ls->linenumber;
+      luaX_next(ls);
+      expr(ls, v);
+      check_match(ls, ')', '(', line);
+      luaK_dischargevars(ls->fs, v);
+      return;
+    }
+    case TK_NAME: {
+      singlevar(ls, v);
+      return;
+    }
+    default: {
+      luaX_syntaxerror(ls, "unexpected symbol");
+      return;
+    }
+  }
+}
+
+
+static void primaryexp (LexState *ls, expdesc *v) {
+  /* primaryexp ->
+        prefixexp { `.' NAME | `[' exp `]' | `:' NAME funcargs | funcargs } */
+  FuncState *fs = ls->fs;
+  prefixexp(ls, v);
+  for (;;) {
+    switch (ls->t.token) {
+      case '.': {  /* field */
+        field(ls, v);
+        break;
+      }
+      case '[': {  /* `[' exp1 `]' */
+        expdesc key;
+        luaK_exp2anyreg(fs, v);
+        yindex(ls, &key);
+        luaK_indexed(fs, v, &key);
+        break;
+      }
+      case ':': {  /* `:' NAME funcargs */
+        expdesc key;
+        luaX_next(ls);
+        checkname(ls, &key);
+        luaK_self(fs, v, &key);
+        funcargs(ls, v);
+        break;
+      }
+      case '(': case TK_STRING: case '{': {  /* funcargs */
+        luaK_exp2nextreg(fs, v);
+        funcargs(ls, v);
+        break;
+      }
+      default: return;
+    }
+  }
+}
+
+
+static void simpleexp (LexState *ls, expdesc *v) {
+  /* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
+                  constructor | FUNCTION body | primaryexp */
+  switch (ls->t.token) {
+    case TK_NUMBER: {
+      init_exp(v, VKNUM, 0);
+      v->u.nval = ls->t.seminfo.r;
+      break;
+    }
+    case TK_STRING: {
+      codestring(ls, v, ls->t.seminfo.ts);
+      break;
+    }
+    case TK_NIL: {
+      init_exp(v, VNIL, 0);
+      break;
+    }
+    case TK_TRUE: {
+      init_exp(v, VTRUE, 0);
+      break;
+    }
+    case TK_FALSE: {
+      init_exp(v, VFALSE, 0);
+      break;
+    }
+    case TK_DOTS: {  /* vararg */
+      FuncState *fs = ls->fs;
+      check_condition(ls, fs->f->is_vararg,
+                      "cannot use " LUA_QL("...") " outside a vararg function");
+      fs->f->is_vararg &= ~VARARG_NEEDSARG;  /* don't need 'arg' */
+      init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 1, 0));
+      break;
+    }
+    case '{': {  /* constructor */
+      constructor(ls, v);
+      return;
+    }
+    case TK_FUNCTION: {
+      luaX_next(ls);
+      body(ls, v, 0, ls->linenumber);
+      return;
+    }
+    default: {
+      primaryexp(ls, v);
+      return;
+    }
+  }
+  luaX_next(ls);
+}
+
+
+static UnOpr getunopr (int op) {
+  switch (op) {
+    case TK_NOT: return OPR_NOT;
+    case '-': return OPR_MINUS;
+    case '#': return OPR_LEN;
+    default: return OPR_NOUNOPR;
+  }
+}
+
+
+static BinOpr getbinopr (int op) {
+  switch (op) {
+    case '+': return OPR_ADD;
+    case '-': return OPR_SUB;
+    case '*': return OPR_MUL;
+    case '/': return OPR_DIV;
+    case '%': return OPR_MOD;
+    case '^': return OPR_POW;
+    case TK_CONCAT: return OPR_CONCAT;
+    case TK_NE: return OPR_NE;
+    case TK_EQ: return OPR_EQ;
+    case '<': return OPR_LT;
+    case TK_LE: return OPR_LE;
+    case '>': return OPR_GT;
+    case TK_GE: return OPR_GE;
+    case TK_AND: return OPR_AND;
+    case TK_OR: return OPR_OR;
+    default: return OPR_NOBINOPR;
+  }
+}
+
+
+static const struct {
+  lu_byte left;  /* left priority for each binary operator */
+  lu_byte right; /* right priority */
+} priority[] = {  /* ORDER OPR */
+   {6, 6}, {6, 6}, {7, 7}, {7, 7}, {7, 7},  /* `+' `-' `/' `%' */
+   {10, 9}, {5, 4},                 /* power and concat (right associative) */
+   {3, 3}, {3, 3},                  /* equality and inequality */
+   {3, 3}, {3, 3}, {3, 3}, {3, 3},  /* order */
+   {2, 2}, {1, 1}                   /* logical (and/or) */
+};
+
+#define UNARY_PRIORITY	8  /* priority for unary operators */
+
+
+/*
+** subexpr -> (simpleexp | unop subexpr) { binop subexpr }
+** where `binop' is any binary operator with a priority higher than `limit'
+*/
+static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
+  BinOpr op;
+  UnOpr uop;
+  enterlevel(ls);
+  uop = getunopr(ls->t.token);
+  if (uop != OPR_NOUNOPR) {
+    luaX_next(ls);
+    subexpr(ls, v, UNARY_PRIORITY);
+    luaK_prefix(ls->fs, uop, v);
+  }
+  else simpleexp(ls, v);
+  /* expand while operators have priorities higher than `limit' */
+  op = getbinopr(ls->t.token);
+  while (op != OPR_NOBINOPR && priority[op].left > limit) {
+    expdesc v2;
+    BinOpr nextop;
+    luaX_next(ls);
+    luaK_infix(ls->fs, op, v);
+    /* read sub-expression with higher priority */
+    nextop = subexpr(ls, &v2, priority[op].right);
+    luaK_posfix(ls->fs, op, v, &v2);
+    op = nextop;
+  }
+  leavelevel(ls);
+  return op;  /* return first untreated operator */
+}
+
+
+static void expr (LexState *ls, expdesc *v) {
+  subexpr(ls, v, 0);
+}
+
+/* }==================================================================== */
+
+
+
+/*
+** {======================================================================
+** Rules for Statements
+** =======================================================================
+*/
+
+
+static int block_follow (int token) {
+  switch (token) {
+    case TK_ELSE: case TK_ELSEIF: case TK_END:
+    case TK_UNTIL: case TK_EOS:
+      return 1;
+    default: return 0;
+  }
+}
+
+
+static void block (LexState *ls) {
+  /* block -> chunk */
+  FuncState *fs = ls->fs;
+  BlockCnt bl;
+  enterblock(fs, &bl, 0);
+  chunk(ls);
+  lua_assert(bl.breaklist == NO_JUMP);
+  leaveblock(fs);
+}
+
+
+/*
+** structure to chain all variables in the left-hand side of an
+** assignment
+*/
+struct LHS_assign {
+  struct LHS_assign *prev;
+  expdesc v;  /* variable (global, local, upvalue, or indexed) */
+};
+
+
+/*
+** check whether, in an assignment to a local variable, the local variable
+** is needed in a previous assignment (to a table). If so, save original
+** local value in a safe place and use this safe copy in the previous
+** assignment.
+*/
+static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
+  FuncState *fs = ls->fs;
+  int extra = fs->freereg;  /* eventual position to save local variable */
+  int conflict = 0;
+  for (; lh; lh = lh->prev) {
+    if (lh->v.k == VINDEXED) {
+      if (lh->v.u.s.info == v->u.s.info) {  /* conflict? */
+        conflict = 1;
+        lh->v.u.s.info = extra;  /* previous assignment will use safe copy */
+      }
+      if (lh->v.u.s.aux == v->u.s.info) {  /* conflict? */
+        conflict = 1;
+        lh->v.u.s.aux = extra;  /* previous assignment will use safe copy */
+      }
+    }
+  }
+  if (conflict) {
+    luaK_codeABC(fs, OP_MOVE, fs->freereg, v->u.s.info, 0);  /* make copy */
+    luaK_reserveregs(fs, 1);
+  }
+}
+
+
+static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
+  expdesc e;
+  check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
+                      "syntax error");
+  if (testnext(ls, ',')) {  /* assignment -> `,' primaryexp assignment */
+    struct LHS_assign nv;
+    nv.prev = lh;
+    primaryexp(ls, &nv.v);
+    if (nv.v.k == VLOCAL)
+      check_conflict(ls, lh, &nv.v);
+    luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
+                    "variables in assignment");
+    assignment(ls, &nv, nvars+1);
+  }
+  else {  /* assignment -> `=' explist1 */
+    int nexps;
+    checknext(ls, '=');
+    nexps = explist1(ls, &e);
+    if (nexps != nvars) {
+      adjust_assign(ls, nvars, nexps, &e);
+      if (nexps > nvars)
+        ls->fs->freereg -= nexps - nvars;  /* remove extra values */
+    }
+    else {
+      luaK_setoneret(ls->fs, &e);  /* close last expression */
+      luaK_storevar(ls->fs, &lh->v, &e);
+      return;  /* avoid default */
+    }
+  }
+  init_exp(&e, VNONRELOC, ls->fs->freereg-1);  /* default assignment */
+  luaK_storevar(ls->fs, &lh->v, &e);
+}
+
+
+static int cond (LexState *ls) {
+  /* cond -> exp */
+  expdesc v;
+  expr(ls, &v);  /* read condition */
+  if (v.k == VNIL) v.k = VFALSE;  /* `falses' are all equal here */
+  luaK_goiftrue(ls->fs, &v);
+  return v.f;
+}
+
+
+static void breakstat (LexState *ls) {
+  FuncState *fs = ls->fs;
+  BlockCnt *bl = fs->bl;
+  int upval = 0;
+  while (bl && !bl->isbreakable) {
+    upval |= bl->upval;
+    bl = bl->previous;
+  }
+  if (!bl)
+    luaX_syntaxerror(ls, "no loop to break");
+  if (upval)
+    luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
+  luaK_concat(fs, &bl->breaklist, luaK_jump(fs));
+}
+
+
+static void whilestat (LexState *ls, int line) {
+  /* whilestat -> WHILE cond DO block END */
+  FuncState *fs = ls->fs;
+  int whileinit;
+  int condexit;
+  BlockCnt bl;
+  luaX_next(ls);  /* skip WHILE */
+  whileinit = luaK_getlabel(fs);
+  condexit = cond(ls);
+  enterblock(fs, &bl, 1);
+  checknext(ls, TK_DO);
+  block(ls);
+  luaK_patchlist(fs, luaK_jump(fs), whileinit);
+  check_match(ls, TK_END, TK_WHILE, line);
+  leaveblock(fs);
+  luaK_patchtohere(fs, condexit);  /* false conditions finish the loop */
+}
+
+
+static void repeatstat (LexState *ls, int line) {
+  /* repeatstat -> REPEAT block UNTIL cond */
+  int condexit;
+  FuncState *fs = ls->fs;
+  int repeat_init = luaK_getlabel(fs);
+  BlockCnt bl1, bl2;
+  enterblock(fs, &bl1, 1);  /* loop block */
+  enterblock(fs, &bl2, 0);  /* scope block */
+  luaX_next(ls);  /* skip REPEAT */
+  chunk(ls);
+  check_match(ls, TK_UNTIL, TK_REPEAT, line);
+  condexit = cond(ls);  /* read condition (inside scope block) */
+  if (!bl2.upval) {  /* no upvalues? */
+    leaveblock(fs);  /* finish scope */
+    luaK_patchlist(ls->fs, condexit, repeat_init);  /* close the loop */
+  }
+  else {  /* complete semantics when there are upvalues */
+    breakstat(ls);  /* if condition then break */
+    luaK_patchtohere(ls->fs, condexit);  /* else... */
+    leaveblock(fs);  /* finish scope... */
+    luaK_patchlist(ls->fs, luaK_jump(fs), repeat_init);  /* and repeat */
+  }
+  leaveblock(fs);  /* finish loop */
+}
+
+
+static int exp1 (LexState *ls) {
+  expdesc e;
+  int k;
+  expr(ls, &e);
+  k = e.k;
+  luaK_exp2nextreg(ls->fs, &e);
+  return k;
+}
+
+
+static void forbody (LexState *ls, int base, int line, int nvars, int isnum) {
+  /* forbody -> DO block */
+  BlockCnt bl;
+  FuncState *fs = ls->fs;
+  int prep, endfor;
+  adjustlocalvars(ls, 3);  /* control variables */
+  checknext(ls, TK_DO);
+  prep = isnum ? luaK_codeAsBx(fs, OP_FORPREP, base, NO_JUMP) : luaK_jump(fs);
+  enterblock(fs, &bl, 0);  /* scope for declared variables */
+  adjustlocalvars(ls, nvars);
+  luaK_reserveregs(fs, nvars);
+  block(ls);
+  leaveblock(fs);  /* end of scope for declared variables */
+  luaK_patchtohere(fs, prep);
+  endfor = (isnum) ? luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP) :
+                     luaK_codeABC(fs, OP_TFORLOOP, base, 0, nvars);
+  luaK_fixline(fs, line);  /* pretend that `OP_FOR' starts the loop */
+  luaK_patchlist(fs, (isnum ? endfor : luaK_jump(fs)), prep + 1);
+}
+
+
+static void fornum (LexState *ls, TString *varname, int line) {
+  /* fornum -> NAME = exp1,exp1[,exp1] forbody */
+  FuncState *fs = ls->fs;
+  int base = fs->freereg;
+  new_localvarliteral(ls, "(for index)", 0);
+  new_localvarliteral(ls, "(for limit)", 1);
+  new_localvarliteral(ls, "(for step)", 2);
+  new_localvar(ls, varname, 3);
+  checknext(ls, '=');
+  exp1(ls);  /* initial value */
+  checknext(ls, ',');
+  exp1(ls);  /* limit */
+  if (testnext(ls, ','))
+    exp1(ls);  /* optional step */
+  else {  /* default step = 1 */
+    luaK_codeABx(fs, OP_LOADK, fs->freereg, luaK_numberK(fs, 1));
+    luaK_reserveregs(fs, 1);
+  }
+  forbody(ls, base, line, 1, 1);
+}
+
+
+static void forlist (LexState *ls, TString *indexname) {
+  /* forlist -> NAME {,NAME} IN explist1 forbody */
+  FuncState *fs = ls->fs;
+  expdesc e;
+  int nvars = 0;
+  int line;
+  int base = fs->freereg;
+  /* create control variables */
+  new_localvarliteral(ls, "(for generator)", nvars++);
+  new_localvarliteral(ls, "(for state)", nvars++);
+  new_localvarliteral(ls, "(for control)", nvars++);
+  /* create declared variables */
+  new_localvar(ls, indexname, nvars++);
+  while (testnext(ls, ','))
+    new_localvar(ls, str_checkname(ls), nvars++);
+  checknext(ls, TK_IN);
+  line = ls->linenumber;
+  adjust_assign(ls, 3, explist1(ls, &e), &e);
+  luaK_checkstack(fs, 3);  /* extra space to call generator */
+  forbody(ls, base, line, nvars - 3, 0);
+}
+
+
+static void forstat (LexState *ls, int line) {
+  /* forstat -> FOR (fornum | forlist) END */
+  FuncState *fs = ls->fs;
+  TString *varname;
+  BlockCnt bl;
+  enterblock(fs, &bl, 1);  /* scope for loop and control variables */
+  luaX_next(ls);  /* skip `for' */
+  varname = str_checkname(ls);  /* first variable name */
+  switch (ls->t.token) {
+    case '=': fornum(ls, varname, line); break;
+    case ',': case TK_IN: forlist(ls, varname); break;
+    default: luaX_syntaxerror(ls, LUA_QL("=") " or " LUA_QL("in") " expected");
+  }
+  check_match(ls, TK_END, TK_FOR, line);
+  leaveblock(fs);  /* loop scope (`break' jumps to this point) */
+}
+
+
+static int test_then_block (LexState *ls) {
+  /* test_then_block -> [IF | ELSEIF] cond THEN block */
+  int condexit;
+  luaX_next(ls);  /* skip IF or ELSEIF */
+  condexit = cond(ls);
+  checknext(ls, TK_THEN);
+  block(ls);  /* `then' part */
+  return condexit;
+}
+
+
+static void ifstat (LexState *ls, int line) {
+  /* ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END */
+  FuncState *fs = ls->fs;
+  int flist;
+  int escapelist = NO_JUMP;
+  flist = test_then_block(ls);  /* IF cond THEN block */
+  while (ls->t.token == TK_ELSEIF) {
+    luaK_concat(fs, &escapelist, luaK_jump(fs));
+    luaK_patchtohere(fs, flist);
+    flist = test_then_block(ls);  /* ELSEIF cond THEN block */
+  }
+  if (ls->t.token == TK_ELSE) {
+    luaK_concat(fs, &escapelist, luaK_jump(fs));
+    luaK_patchtohere(fs, flist);
+    luaX_next(ls);  /* skip ELSE (after patch, for correct line info) */
+    block(ls);  /* `else' part */
+  }
+  else
+    luaK_concat(fs, &escapelist, flist);
+  luaK_patchtohere(fs, escapelist);
+  check_match(ls, TK_END, TK_IF, line);
+}
+
+
+static void localfunc (LexState *ls) {
+  expdesc v, b;
+  FuncState *fs = ls->fs;
+  new_localvar(ls, str_checkname(ls), 0);
+  init_exp(&v, VLOCAL, fs->freereg);
+  luaK_reserveregs(fs, 1);
+  adjustlocalvars(ls, 1);
+  body(ls, &b, 0, ls->linenumber);
+  luaK_storevar(fs, &v, &b);
+  /* debug information will only see the variable after this point! */
+  getlocvar(fs, fs->nactvar - 1).startpc = fs->pc;
+}
+
+
+static void localstat (LexState *ls) {
+  /* stat -> LOCAL NAME {`,' NAME} [`=' explist1] */
+  int nvars = 0;
+  int nexps;
+  expdesc e;
+  do {
+    new_localvar(ls, str_checkname(ls), nvars++);
+  } while (testnext(ls, ','));
+  if (testnext(ls, '='))
+    nexps = explist1(ls, &e);
+  else {
+    e.k = VVOID;
+    nexps = 0;
+  }
+  adjust_assign(ls, nvars, nexps, &e);
+  adjustlocalvars(ls, nvars);
+}
+
+
+static int funcname (LexState *ls, expdesc *v) {
+  /* funcname -> NAME {field} [`:' NAME] */
+  int needself = 0;
+  singlevar(ls, v);
+  while (ls->t.token == '.')
+    field(ls, v);
+  if (ls->t.token == ':') {
+    needself = 1;
+    field(ls, v);
+  }
+  return needself;
+}
+
+
+static void funcstat (LexState *ls, int line) {
+  /* funcstat -> FUNCTION funcname body */
+  int needself;
+  expdesc v, b;
+  luaX_next(ls);  /* skip FUNCTION */
+  needself = funcname(ls, &v);
+  body(ls, &b, needself, line);
+  luaK_storevar(ls->fs, &v, &b);
+  luaK_fixline(ls->fs, line);  /* definition `happens' in the first line */
+}
+
+
+static void exprstat (LexState *ls) {
+  /* stat -> func | assignment */
+  FuncState *fs = ls->fs;
+  struct LHS_assign v;
+  primaryexp(ls, &v.v);
+  if (v.v.k == VCALL)  /* stat -> func */
+    SETARG_C(getcode(fs, &v.v), 1);  /* call statement uses no results */
+  else {  /* stat -> assignment */
+    v.prev = NULL;
+    assignment(ls, &v, 1);
+  }
+}
+
+
+static void retstat (LexState *ls) {
+  /* stat -> RETURN explist */
+  FuncState *fs = ls->fs;
+  expdesc e;
+  int first, nret;  /* registers with returned values */
+  luaX_next(ls);  /* skip RETURN */
+  if (block_follow(ls->t.token) || ls->t.token == ';')
+    first = nret = 0;  /* return no values */
+  else {
+    nret = explist1(ls, &e);  /* optional return values */
+    if (hasmultret(e.k)) {
+      luaK_setmultret(fs, &e);
+      if (e.k == VCALL && nret == 1) {  /* tail call? */
+        SET_OPCODE(getcode(fs,&e), OP_TAILCALL);
+        lua_assert(GETARG_A(getcode(fs,&e)) == fs->nactvar);
+      }
+      first = fs->nactvar;
+      nret = LUA_MULTRET;  /* return all values */
+    }
+    else {
+      if (nret == 1)  /* only one single value? */
+        first = luaK_exp2anyreg(fs, &e);
+      else {
+        luaK_exp2nextreg(fs, &e);  /* values must go to the `stack' */
+        first = fs->nactvar;  /* return all `active' values */
+        lua_assert(nret == fs->freereg - first);
+      }
+    }
+  }
+  luaK_ret(fs, first, nret);
+}
+
+
+static int statement (LexState *ls) {
+  int line = ls->linenumber;  /* may be needed for error messages */
+  switch (ls->t.token) {
+    case TK_IF: {  /* stat -> ifstat */
+      ifstat(ls, line);
+      return 0;
+    }
+    case TK_WHILE: {  /* stat -> whilestat */
+      whilestat(ls, line);
+      return 0;
+    }
+    case TK_DO: {  /* stat -> DO block END */
+      luaX_next(ls);  /* skip DO */
+      block(ls);
+      check_match(ls, TK_END, TK_DO, line);
+      return 0;
+    }
+    case TK_FOR: {  /* stat -> forstat */
+      forstat(ls, line);
+      return 0;
+    }
+    case TK_REPEAT: {  /* stat -> repeatstat */
+      repeatstat(ls, line);
+      return 0;
+    }
+    case TK_FUNCTION: {
+      funcstat(ls, line);  /* stat -> funcstat */
+      return 0;
+    }
+    case TK_LOCAL: {  /* stat -> localstat */
+      luaX_next(ls);  /* skip LOCAL */
+      if (testnext(ls, TK_FUNCTION))  /* local function? */
+        localfunc(ls);
+      else
+        localstat(ls);
+      return 0;
+    }
+    case TK_RETURN: {  /* stat -> retstat */
+      retstat(ls);
+      return 1;  /* must be last statement */
+    }
+    case TK_BREAK: {  /* stat -> breakstat */
+      luaX_next(ls);  /* skip BREAK */
+      breakstat(ls);
+      return 1;  /* must be last statement */
+    }
+    default: {
+      exprstat(ls);
+      return 0;  /* to avoid warnings */
+    }
+  }
+}
+
+
+static void chunk (LexState *ls) {
+  /* chunk -> { stat [`;'] } */
+  int islast = 0;
+  enterlevel(ls);
+  while (!islast && !block_follow(ls->t.token)) {
+    islast = statement(ls);
+    testnext(ls, ';');
+    lua_assert(ls->fs->f->maxstacksize >= ls->fs->freereg &&
+               ls->fs->freereg >= ls->fs->nactvar);
+    ls->fs->freereg = ls->fs->nactvar;  /* free registers */
+  }
+  leavelevel(ls);
+}
+
+/* }====================================================================== */
diff --git a/third_party/lua-src/lua-5.1.5/lparser.h b/third_party/lua-src/lua-5.1.5/lparser.h
new file mode 100644
index 00000000..18836afd
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lparser.h
@@ -0,0 +1,82 @@
+/*
+** $Id: lparser.h,v 1.57.1.1 2007/12/27 13:02:25 roberto Exp $
+** Lua Parser
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lparser_h
+#define lparser_h
+
+#include "llimits.h"
+#include "lobject.h"
+#include "lzio.h"
+
+
+/*
+** Expression descriptor
+*/
+
+typedef enum {
+  VVOID,	/* no value */
+  VNIL,
+  VTRUE,
+  VFALSE,
+  VK,		/* info = index of constant in `k' */
+  VKNUM,	/* nval = numerical value */
+  VLOCAL,	/* info = local register */
+  VUPVAL,       /* info = index of upvalue in `upvalues' */
+  VGLOBAL,	/* info = index of table; aux = index of global name in `k' */
+  VINDEXED,	/* info = table register; aux = index register (or `k') */
+  VJMP,		/* info = instruction pc */
+  VRELOCABLE,	/* info = instruction pc */
+  VNONRELOC,	/* info = result register */
+  VCALL,	/* info = instruction pc */
+  VVARARG	/* info = instruction pc */
+} expkind;
+
+typedef struct expdesc {
+  expkind k;
+  union {
+    struct { int info, aux; } s;
+    lua_Number nval;
+  } u;
+  int t;  /* patch list of `exit when true' */
+  int f;  /* patch list of `exit when false' */
+} expdesc;
+
+
+typedef struct upvaldesc {
+  lu_byte k;
+  lu_byte info;
+} upvaldesc;
+
+
+struct BlockCnt;  /* defined in lparser.c */
+
+
+/* state needed to generate code for a given function */
+typedef struct FuncState {
+  Proto *f;  /* current function header */
+  Table *h;  /* table to find (and reuse) elements in `k' */
+  struct FuncState *prev;  /* enclosing function */
+  struct LexState *ls;  /* lexical state */
+  struct lua_State *L;  /* copy of the Lua state */
+  struct BlockCnt *bl;  /* chain of current blocks */
+  int pc;  /* next position to code (equivalent to `ncode') */
+  int lasttarget;   /* `pc' of last `jump target' */
+  int jpc;  /* list of pending jumps to `pc' */
+  int freereg;  /* first free register */
+  int nk;  /* number of elements in `k' */
+  int np;  /* number of elements in `p' */
+  short nlocvars;  /* number of elements in `locvars' */
+  lu_byte nactvar;  /* number of active local variables */
+  upvaldesc upvalues[LUAI_MAXUPVALUES];  /* upvalues */
+  unsigned short actvar[LUAI_MAXVARS];  /* declared-variable stack */
+} FuncState;
+
+
+LUAI_FUNC Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
+                                            const char *name);
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lstate.c b/third_party/lua-src/lua-5.1.5/lstate.c
new file mode 100644
index 00000000..4313b83a
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lstate.c
@@ -0,0 +1,214 @@
+/*
+** $Id: lstate.c,v 2.36.1.2 2008/01/03 15:20:39 roberto Exp $
+** Global State
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define lstate_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+#define state_size(x)	(sizeof(x) + LUAI_EXTRASPACE)
+#define fromstate(l)	(cast(lu_byte *, (l)) - LUAI_EXTRASPACE)
+#define tostate(l)   (cast(lua_State *, cast(lu_byte *, l) + LUAI_EXTRASPACE))
+
+
+/*
+** Main thread combines a thread state and the global state
+*/
+typedef struct LG {
+  lua_State l;
+  global_State g;
+} LG;
+  
+
+
+static void stack_init (lua_State *L1, lua_State *L) {
+  /* initialize CallInfo array */
+  L1->base_ci = luaM_newvector(L, BASIC_CI_SIZE, CallInfo);
+  L1->ci = L1->base_ci;
+  L1->size_ci = BASIC_CI_SIZE;
+  L1->end_ci = L1->base_ci + L1->size_ci - 1;
+  /* initialize stack array */
+  L1->stack = luaM_newvector(L, BASIC_STACK_SIZE + EXTRA_STACK, TValue);
+  L1->stacksize = BASIC_STACK_SIZE + EXTRA_STACK;
+  L1->top = L1->stack;
+  L1->stack_last = L1->stack+(L1->stacksize - EXTRA_STACK)-1;
+  /* initialize first ci */
+  L1->ci->func = L1->top;
+  setnilvalue(L1->top++);  /* `function' entry for this `ci' */
+  L1->base = L1->ci->base = L1->top;
+  L1->ci->top = L1->top + LUA_MINSTACK;
+}
+
+
+static void freestack (lua_State *L, lua_State *L1) {
+  luaM_freearray(L, L1->base_ci, L1->size_ci, CallInfo);
+  luaM_freearray(L, L1->stack, L1->stacksize, TValue);
+}
+
+
+/*
+** open parts that may cause memory-allocation errors
+*/
+static void f_luaopen (lua_State *L, void *ud) {
+  global_State *g = G(L);
+  UNUSED(ud);
+  stack_init(L, L);  /* init stack */
+  sethvalue(L, gt(L), luaH_new(L, 0, 2));  /* table of globals */
+  sethvalue(L, registry(L), luaH_new(L, 0, 2));  /* registry */
+  luaS_resize(L, MINSTRTABSIZE);  /* initial size of string table */
+  luaT_init(L);
+  luaX_init(L);
+  luaS_fix(luaS_newliteral(L, MEMERRMSG));
+  g->GCthreshold = 4*g->totalbytes;
+}
+
+
+static void preinit_state (lua_State *L, global_State *g) {
+  G(L) = g;
+  L->stack = NULL;
+  L->stacksize = 0;
+  L->errorJmp = NULL;
+  L->hook = NULL;
+  L->hookmask = 0;
+  L->basehookcount = 0;
+  L->allowhook = 1;
+  resethookcount(L);
+  L->openupval = NULL;
+  L->size_ci = 0;
+  L->nCcalls = L->baseCcalls = 0;
+  L->status = 0;
+  L->base_ci = L->ci = NULL;
+  L->savedpc = NULL;
+  L->errfunc = 0;
+  setnilvalue(gt(L));
+}
+
+
+static void close_state (lua_State *L) {
+  global_State *g = G(L);
+  luaF_close(L, L->stack);  /* close all upvalues for this thread */
+  luaC_freeall(L);  /* collect all objects */
+  lua_assert(g->rootgc == obj2gco(L));
+  lua_assert(g->strt.nuse == 0);
+  luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size, TString *);
+  luaZ_freebuffer(L, &g->buff);
+  freestack(L, L);
+  lua_assert(g->totalbytes == sizeof(LG));
+  (*g->frealloc)(g->ud, fromstate(L), state_size(LG), 0);
+}
+
+
+lua_State *luaE_newthread (lua_State *L) {
+  lua_State *L1 = tostate(luaM_malloc(L, state_size(lua_State)));
+  luaC_link(L, obj2gco(L1), LUA_TTHREAD);
+  preinit_state(L1, G(L));
+  stack_init(L1, L);  /* init stack */
+  setobj2n(L, gt(L1), gt(L));  /* share table of globals */
+  L1->hookmask = L->hookmask;
+  L1->basehookcount = L->basehookcount;
+  L1->hook = L->hook;
+  resethookcount(L1);
+  lua_assert(iswhite(obj2gco(L1)));
+  return L1;
+}
+
+
+void luaE_freethread (lua_State *L, lua_State *L1) {
+  luaF_close(L1, L1->stack);  /* close all upvalues for this thread */
+  lua_assert(L1->openupval == NULL);
+  luai_userstatefree(L1);
+  freestack(L, L1);
+  luaM_freemem(L, fromstate(L1), state_size(lua_State));
+}
+
+
+LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
+  int i;
+  lua_State *L;
+  global_State *g;
+  void *l = (*f)(ud, NULL, 0, state_size(LG));
+  if (l == NULL) return NULL;
+  L = tostate(l);
+  g = &((LG *)L)->g;
+  L->next = NULL;
+  L->tt = LUA_TTHREAD;
+  g->currentwhite = bit2mask(WHITE0BIT, FIXEDBIT);
+  L->marked = luaC_white(g);
+  set2bits(L->marked, FIXEDBIT, SFIXEDBIT);
+  preinit_state(L, g);
+  g->frealloc = f;
+  g->ud = ud;
+  g->mainthread = L;
+  g->uvhead.u.l.prev = &g->uvhead;
+  g->uvhead.u.l.next = &g->uvhead;
+  g->GCthreshold = 0;  /* mark it as unfinished state */
+  g->strt.size = 0;
+  g->strt.nuse = 0;
+  g->strt.hash = NULL;
+  setnilvalue(registry(L));
+  luaZ_initbuffer(L, &g->buff);
+  g->panic = NULL;
+  g->gcstate = GCSpause;
+  g->rootgc = obj2gco(L);
+  g->sweepstrgc = 0;
+  g->sweepgc = &g->rootgc;
+  g->gray = NULL;
+  g->grayagain = NULL;
+  g->weak = NULL;
+  g->tmudata = NULL;
+  g->totalbytes = sizeof(LG);
+  g->gcpause = LUAI_GCPAUSE;
+  g->gcstepmul = LUAI_GCMUL;
+  g->gcdept = 0;
+  for (i=0; i<NUM_TAGS; i++) g->mt[i] = NULL;
+  if (luaD_rawrunprotected(L, f_luaopen, NULL) != 0) {
+    /* memory allocation error: free partial state */
+    close_state(L);
+    L = NULL;
+  }
+  else
+    luai_userstateopen(L);
+  return L;
+}
+
+
+static void callallgcTM (lua_State *L, void *ud) {
+  UNUSED(ud);
+  luaC_callGCTM(L);  /* call GC metamethods for all udata */
+}
+
+
+LUA_API void lua_close (lua_State *L) {
+  L = G(L)->mainthread;  /* only the main thread can be closed */
+  lua_lock(L);
+  luaF_close(L, L->stack);  /* close all upvalues for this thread */
+  luaC_separateudata(L, 1);  /* separate udata that have GC metamethods */
+  L->errfunc = 0;  /* no error function during GC metamethods */
+  do {  /* repeat until no more errors */
+    L->ci = L->base_ci;
+    L->base = L->top = L->ci->base;
+    L->nCcalls = L->baseCcalls = 0;
+  } while (luaD_rawrunprotected(L, callallgcTM, NULL) != 0);
+  lua_assert(G(L)->tmudata == NULL);
+  luai_userstateclose(L);
+  close_state(L);
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lstate.h b/third_party/lua-src/lua-5.1.5/lstate.h
new file mode 100644
index 00000000..3bc575b6
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lstate.h
@@ -0,0 +1,169 @@
+/*
+** $Id: lstate.h,v 2.24.1.2 2008/01/03 15:20:39 roberto Exp $
+** Global State
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lstate_h
+#define lstate_h
+
+#include "lua.h"
+
+#include "lobject.h"
+#include "ltm.h"
+#include "lzio.h"
+
+
+
+struct lua_longjmp;  /* defined in ldo.c */
+
+
+/* table of globals */
+#define gt(L)	(&L->l_gt)
+
+/* registry */
+#define registry(L)	(&G(L)->l_registry)
+
+
+/* extra stack space to handle TM calls and some other extras */
+#define EXTRA_STACK   5
+
+
+#define BASIC_CI_SIZE           8
+
+#define BASIC_STACK_SIZE        (2*LUA_MINSTACK)
+
+
+
+typedef struct stringtable {
+  GCObject **hash;
+  lu_int32 nuse;  /* number of elements */
+  int size;
+} stringtable;
+
+
+/*
+** informations about a call
+*/
+typedef struct CallInfo {
+  StkId base;  /* base for this function */
+  StkId func;  /* function index in the stack */
+  StkId	top;  /* top for this function */
+  const Instruction *savedpc;
+  int nresults;  /* expected number of results from this function */
+  int tailcalls;  /* number of tail calls lost under this entry */
+} CallInfo;
+
+
+
+#define curr_func(L)	(clvalue(L->ci->func))
+#define ci_func(ci)	(clvalue((ci)->func))
+#define f_isLua(ci)	(!ci_func(ci)->c.isC)
+#define isLua(ci)	(ttisfunction((ci)->func) && f_isLua(ci))
+
+
+/*
+** `global state', shared by all threads of this state
+*/
+typedef struct global_State {
+  stringtable strt;  /* hash table for strings */
+  lua_Alloc frealloc;  /* function to reallocate memory */
+  void *ud;         /* auxiliary data to `frealloc' */
+  lu_byte currentwhite;
+  lu_byte gcstate;  /* state of garbage collector */
+  int sweepstrgc;  /* position of sweep in `strt' */
+  GCObject *rootgc;  /* list of all collectable objects */
+  GCObject **sweepgc;  /* position of sweep in `rootgc' */
+  GCObject *gray;  /* list of gray objects */
+  GCObject *grayagain;  /* list of objects to be traversed atomically */
+  GCObject *weak;  /* list of weak tables (to be cleared) */
+  GCObject *tmudata;  /* last element of list of userdata to be GC */
+  Mbuffer buff;  /* temporary buffer for string concatentation */
+  lu_mem GCthreshold;
+  lu_mem totalbytes;  /* number of bytes currently allocated */
+  lu_mem estimate;  /* an estimate of number of bytes actually in use */
+  lu_mem gcdept;  /* how much GC is `behind schedule' */
+  int gcpause;  /* size of pause between successive GCs */
+  int gcstepmul;  /* GC `granularity' */
+  lua_CFunction panic;  /* to be called in unprotected errors */
+  TValue l_registry;
+  struct lua_State *mainthread;
+  UpVal uvhead;  /* head of double-linked list of all open upvalues */
+  struct Table *mt[NUM_TAGS];  /* metatables for basic types */
+  TString *tmname[TM_N];  /* array with tag-method names */
+} global_State;
+
+
+/*
+** `per thread' state
+*/
+struct lua_State {
+  CommonHeader;
+  lu_byte status;
+  StkId top;  /* first free slot in the stack */
+  StkId base;  /* base of current function */
+  global_State *l_G;
+  CallInfo *ci;  /* call info for current function */
+  const Instruction *savedpc;  /* `savedpc' of current function */
+  StkId stack_last;  /* last free slot in the stack */
+  StkId stack;  /* stack base */
+  CallInfo *end_ci;  /* points after end of ci array*/
+  CallInfo *base_ci;  /* array of CallInfo's */
+  int stacksize;
+  int size_ci;  /* size of array `base_ci' */
+  unsigned short nCcalls;  /* number of nested C calls */
+  unsigned short baseCcalls;  /* nested C calls when resuming coroutine */
+  lu_byte hookmask;
+  lu_byte allowhook;
+  int basehookcount;
+  int hookcount;
+  lua_Hook hook;
+  TValue l_gt;  /* table of globals */
+  TValue env;  /* temporary place for environments */
+  GCObject *openupval;  /* list of open upvalues in this stack */
+  GCObject *gclist;
+  struct lua_longjmp *errorJmp;  /* current error recover point */
+  ptrdiff_t errfunc;  /* current error handling function (stack index) */
+};
+
+
+#define G(L)	(L->l_G)
+
+
+/*
+** Union of all collectable objects
+*/
+union GCObject {
+  GCheader gch;
+  union TString ts;
+  union Udata u;
+  union Closure cl;
+  struct Table h;
+  struct Proto p;
+  struct UpVal uv;
+  struct lua_State th;  /* thread */
+};
+
+
+/* macros to convert a GCObject into a specific value */
+#define rawgco2ts(o)	check_exp((o)->gch.tt == LUA_TSTRING, &((o)->ts))
+#define gco2ts(o)	(&rawgco2ts(o)->tsv)
+#define rawgco2u(o)	check_exp((o)->gch.tt == LUA_TUSERDATA, &((o)->u))
+#define gco2u(o)	(&rawgco2u(o)->uv)
+#define gco2cl(o)	check_exp((o)->gch.tt == LUA_TFUNCTION, &((o)->cl))
+#define gco2h(o)	check_exp((o)->gch.tt == LUA_TTABLE, &((o)->h))
+#define gco2p(o)	check_exp((o)->gch.tt == LUA_TPROTO, &((o)->p))
+#define gco2uv(o)	check_exp((o)->gch.tt == LUA_TUPVAL, &((o)->uv))
+#define ngcotouv(o) \
+	check_exp((o) == NULL || (o)->gch.tt == LUA_TUPVAL, &((o)->uv))
+#define gco2th(o)	check_exp((o)->gch.tt == LUA_TTHREAD, &((o)->th))
+
+/* macro to convert any Lua object into a GCObject */
+#define obj2gco(v)	(cast(GCObject *, (v)))
+
+
+LUAI_FUNC lua_State *luaE_newthread (lua_State *L);
+LUAI_FUNC void luaE_freethread (lua_State *L, lua_State *L1);
+
+#endif
+
diff --git a/third_party/lua-src/lua-5.1.5/lstring.c b/third_party/lua-src/lua-5.1.5/lstring.c
new file mode 100644
index 00000000..49113151
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lstring.c
@@ -0,0 +1,111 @@
+/*
+** $Id: lstring.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** String table (keeps all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#define lstring_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+
+
+
+void luaS_resize (lua_State *L, int newsize) {
+  GCObject **newhash;
+  stringtable *tb;
+  int i;
+  if (G(L)->gcstate == GCSsweepstring)
+    return;  /* cannot resize during GC traverse */
+  newhash = luaM_newvector(L, newsize, GCObject *);
+  tb = &G(L)->strt;
+  for (i=0; i<newsize; i++) newhash[i] = NULL;
+  /* rehash */
+  for (i=0; i<tb->size; i++) {
+    GCObject *p = tb->hash[i];
+    while (p) {  /* for each node in the list */
+      GCObject *next = p->gch.next;  /* save next */
+      unsigned int h = gco2ts(p)->hash;
+      int h1 = lmod(h, newsize);  /* new position */
+      lua_assert(cast_int(h%newsize) == lmod(h, newsize));
+      p->gch.next = newhash[h1];  /* chain it */
+      newhash[h1] = p;
+      p = next;
+    }
+  }
+  luaM_freearray(L, tb->hash, tb->size, TString *);
+  tb->size = newsize;
+  tb->hash = newhash;
+}
+
+
+static TString *newlstr (lua_State *L, const char *str, size_t l,
+                                       unsigned int h) {
+  TString *ts;
+  stringtable *tb;
+  if (l+1 > (MAX_SIZET - sizeof(TString))/sizeof(char))
+    luaM_toobig(L);
+  ts = cast(TString *, luaM_malloc(L, (l+1)*sizeof(char)+sizeof(TString)));
+  ts->tsv.len = l;
+  ts->tsv.hash = h;
+  ts->tsv.marked = luaC_white(G(L));
+  ts->tsv.tt = LUA_TSTRING;
+  ts->tsv.reserved = 0;
+  memcpy(ts+1, str, l*sizeof(char));
+  ((char *)(ts+1))[l] = '\0';  /* ending 0 */
+  tb = &G(L)->strt;
+  h = lmod(h, tb->size);
+  ts->tsv.next = tb->hash[h];  /* chain new entry */
+  tb->hash[h] = obj2gco(ts);
+  tb->nuse++;
+  if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)
+    luaS_resize(L, tb->size*2);  /* too crowded */
+  return ts;
+}
+
+
+TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
+  GCObject *o;
+  unsigned int h = cast(unsigned int, l);  /* seed */
+  size_t step = (l>>5)+1;  /* if string is too long, don't hash all its chars */
+  size_t l1;
+  for (l1=l; l1>=step; l1-=step)  /* compute hash */
+    h = h ^ ((h<<5)+(h>>2)+cast(unsigned char, str[l1-1]));
+  for (o = G(L)->strt.hash[lmod(h, G(L)->strt.size)];
+       o != NULL;
+       o = o->gch.next) {
+    TString *ts = rawgco2ts(o);
+    if (ts->tsv.len == l && (memcmp(str, getstr(ts), l) == 0)) {
+      /* string may be dead */
+      if (isdead(G(L), o)) changewhite(o);
+      return ts;
+    }
+  }
+  return newlstr(L, str, l, h);  /* not found */
+}
+
+
+Udata *luaS_newudata (lua_State *L, size_t s, Table *e) {
+  Udata *u;
+  if (s > MAX_SIZET - sizeof(Udata))
+    luaM_toobig(L);
+  u = cast(Udata *, luaM_malloc(L, s + sizeof(Udata)));
+  u->uv.marked = luaC_white(G(L));  /* is not finalized */
+  u->uv.tt = LUA_TUSERDATA;
+  u->uv.len = s;
+  u->uv.metatable = NULL;
+  u->uv.env = e;
+  /* chain it on udata list (after main thread) */
+  u->uv.next = G(L)->mainthread->next;
+  G(L)->mainthread->next = obj2gco(u);
+  return u;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lstring.h b/third_party/lua-src/lua-5.1.5/lstring.h
new file mode 100644
index 00000000..73a2ff8b
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lstring.h
@@ -0,0 +1,31 @@
+/*
+** $Id: lstring.h,v 1.43.1.1 2007/12/27 13:02:25 roberto Exp $
+** String table (keep all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lstring_h
+#define lstring_h
+
+
+#include "lgc.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+#define sizestring(s)	(sizeof(union TString)+((s)->len+1)*sizeof(char))
+
+#define sizeudata(u)	(sizeof(union Udata)+(u)->len)
+
+#define luaS_new(L, s)	(luaS_newlstr(L, s, strlen(s)))
+#define luaS_newliteral(L, s)	(luaS_newlstr(L, "" s, \
+                                 (sizeof(s)/sizeof(char))-1))
+
+#define luaS_fix(s)	l_setbit((s)->tsv.marked, FIXEDBIT)
+
+LUAI_FUNC void luaS_resize (lua_State *L, int newsize);
+LUAI_FUNC Udata *luaS_newudata (lua_State *L, size_t s, Table *e);
+LUAI_FUNC TString *luaS_newlstr (lua_State *L, const char *str, size_t l);
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lstrlib.c b/third_party/lua-src/lua-5.1.5/lstrlib.c
new file mode 100644
index 00000000..7a03489b
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lstrlib.c
@@ -0,0 +1,871 @@
+/*
+** $Id: lstrlib.c,v 1.132.1.5 2010/05/14 15:34:19 roberto Exp $
+** Standard library for string operations and pattern-matching
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lstrlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/* macro to `unsign' a character */
+#define uchar(c)        ((unsigned char)(c))
+
+
+
+static int str_len (lua_State *L) {
+  size_t l;
+  luaL_checklstring(L, 1, &l);
+  lua_pushinteger(L, l);
+  return 1;
+}
+
+
+static ptrdiff_t posrelat (ptrdiff_t pos, size_t len) {
+  /* relative string position: negative means back from end */
+  if (pos < 0) pos += (ptrdiff_t)len + 1;
+  return (pos >= 0) ? pos : 0;
+}
+
+
+static int str_sub (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  ptrdiff_t start = posrelat(luaL_checkinteger(L, 2), l);
+  ptrdiff_t end = posrelat(luaL_optinteger(L, 3, -1), l);
+  if (start < 1) start = 1;
+  if (end > (ptrdiff_t)l) end = (ptrdiff_t)l;
+  if (start <= end)
+    lua_pushlstring(L, s+start-1, end-start+1);
+  else lua_pushliteral(L, "");
+  return 1;
+}
+
+
+static int str_reverse (lua_State *L) {
+  size_t l;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  luaL_buffinit(L, &b);
+  while (l--) luaL_addchar(&b, s[l]);
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int str_lower (lua_State *L) {
+  size_t l;
+  size_t i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  luaL_buffinit(L, &b);
+  for (i=0; i<l; i++)
+    luaL_addchar(&b, tolower(uchar(s[i])));
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int str_upper (lua_State *L) {
+  size_t l;
+  size_t i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  luaL_buffinit(L, &b);
+  for (i=0; i<l; i++)
+    luaL_addchar(&b, toupper(uchar(s[i])));
+  luaL_pushresult(&b);
+  return 1;
+}
+
+static int str_rep (lua_State *L) {
+  size_t l;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  int n = luaL_checkint(L, 2);
+  luaL_buffinit(L, &b);
+  while (n-- > 0)
+    luaL_addlstring(&b, s, l);
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int str_byte (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  ptrdiff_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
+  ptrdiff_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
+  int n, i;
+  if (posi <= 0) posi = 1;
+  if ((size_t)pose > l) pose = l;
+  if (posi > pose) return 0;  /* empty interval; return no values */
+  n = (int)(pose -  posi + 1);
+  if (posi + n <= pose)  /* overflow? */
+    luaL_error(L, "string slice too long");
+  luaL_checkstack(L, n, "string slice too long");
+  for (i=0; i<n; i++)
+    lua_pushinteger(L, uchar(s[posi+i-1]));
+  return n;
+}
+
+
+static int str_char (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  for (i=1; i<=n; i++) {
+    int c = luaL_checkint(L, i);
+    luaL_argcheck(L, uchar(c) == c, i, "invalid value");
+    luaL_addchar(&b, uchar(c));
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int writer (lua_State *L, const void* b, size_t size, void* B) {
+  (void)L;
+  luaL_addlstring((luaL_Buffer*) B, (const char *)b, size);
+  return 0;
+}
+
+
+static int str_dump (lua_State *L) {
+  luaL_Buffer b;
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  lua_settop(L, 1);
+  luaL_buffinit(L,&b);
+  if (lua_dump(L, writer, &b) != 0)
+    luaL_error(L, "unable to dump given function");
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+
+/*
+** {======================================================
+** PATTERN MATCHING
+** =======================================================
+*/
+
+
+#define CAP_UNFINISHED	(-1)
+#define CAP_POSITION	(-2)
+
+typedef struct MatchState {
+  const char *src_init;  /* init of source string */
+  const char *src_end;  /* end (`\0') of source string */
+  lua_State *L;
+  int level;  /* total number of captures (finished or unfinished) */
+  struct {
+    const char *init;
+    ptrdiff_t len;
+  } capture[LUA_MAXCAPTURES];
+} MatchState;
+
+
+#define L_ESC		'%'
+#define SPECIALS	"^$*+?.([%-"
+
+
+static int check_capture (MatchState *ms, int l) {
+  l -= '1';
+  if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
+    return luaL_error(ms->L, "invalid capture index");
+  return l;
+}
+
+
+static int capture_to_close (MatchState *ms) {
+  int level = ms->level;
+  for (level--; level>=0; level--)
+    if (ms->capture[level].len == CAP_UNFINISHED) return level;
+  return luaL_error(ms->L, "invalid pattern capture");
+}
+
+
+static const char *classend (MatchState *ms, const char *p) {
+  switch (*p++) {
+    case L_ESC: {
+      if (*p == '\0')
+        luaL_error(ms->L, "malformed pattern (ends with " LUA_QL("%%") ")");
+      return p+1;
+    }
+    case '[': {
+      if (*p == '^') p++;
+      do {  /* look for a `]' */
+        if (*p == '\0')
+          luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")");
+        if (*(p++) == L_ESC && *p != '\0')
+          p++;  /* skip escapes (e.g. `%]') */
+      } while (*p != ']');
+      return p+1;
+    }
+    default: {
+      return p;
+    }
+  }
+}
+
+
+static int match_class (int c, int cl) {
+  int res;
+  switch (tolower(cl)) {
+    case 'a' : res = isalpha(c); break;
+    case 'c' : res = iscntrl(c); break;
+    case 'd' : res = isdigit(c); break;
+    case 'l' : res = islower(c); break;
+    case 'p' : res = ispunct(c); break;
+    case 's' : res = isspace(c); break;
+    case 'u' : res = isupper(c); break;
+    case 'w' : res = isalnum(c); break;
+    case 'x' : res = isxdigit(c); break;
+    case 'z' : res = (c == 0); break;
+    default: return (cl == c);
+  }
+  return (islower(cl) ? res : !res);
+}
+
+
+static int matchbracketclass (int c, const char *p, const char *ec) {
+  int sig = 1;
+  if (*(p+1) == '^') {
+    sig = 0;
+    p++;  /* skip the `^' */
+  }
+  while (++p < ec) {
+    if (*p == L_ESC) {
+      p++;
+      if (match_class(c, uchar(*p)))
+        return sig;
+    }
+    else if ((*(p+1) == '-') && (p+2 < ec)) {
+      p+=2;
+      if (uchar(*(p-2)) <= c && c <= uchar(*p))
+        return sig;
+    }
+    else if (uchar(*p) == c) return sig;
+  }
+  return !sig;
+}
+
+
+static int singlematch (int c, const char *p, const char *ep) {
+  switch (*p) {
+    case '.': return 1;  /* matches any char */
+    case L_ESC: return match_class(c, uchar(*(p+1)));
+    case '[': return matchbracketclass(c, p, ep-1);
+    default:  return (uchar(*p) == c);
+  }
+}
+
+
+static const char *match (MatchState *ms, const char *s, const char *p);
+
+
+static const char *matchbalance (MatchState *ms, const char *s,
+                                   const char *p) {
+  if (*p == 0 || *(p+1) == 0)
+    luaL_error(ms->L, "unbalanced pattern");
+  if (*s != *p) return NULL;
+  else {
+    int b = *p;
+    int e = *(p+1);
+    int cont = 1;
+    while (++s < ms->src_end) {
+      if (*s == e) {
+        if (--cont == 0) return s+1;
+      }
+      else if (*s == b) cont++;
+    }
+  }
+  return NULL;  /* string ends out of balance */
+}
+
+
+static const char *max_expand (MatchState *ms, const char *s,
+                                 const char *p, const char *ep) {
+  ptrdiff_t i = 0;  /* counts maximum expand for item */
+  while ((s+i)<ms->src_end && singlematch(uchar(*(s+i)), p, ep))
+    i++;
+  /* keeps trying to match with the maximum repetitions */
+  while (i>=0) {
+    const char *res = match(ms, (s+i), ep+1);
+    if (res) return res;
+    i--;  /* else didn't match; reduce 1 repetition to try again */
+  }
+  return NULL;
+}
+
+
+static const char *min_expand (MatchState *ms, const char *s,
+                                 const char *p, const char *ep) {
+  for (;;) {
+    const char *res = match(ms, s, ep+1);
+    if (res != NULL)
+      return res;
+    else if (s<ms->src_end && singlematch(uchar(*s), p, ep))
+      s++;  /* try with one more repetition */
+    else return NULL;
+  }
+}
+
+
+static const char *start_capture (MatchState *ms, const char *s,
+                                    const char *p, int what) {
+  const char *res;
+  int level = ms->level;
+  if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
+  ms->capture[level].init = s;
+  ms->capture[level].len = what;
+  ms->level = level+1;
+  if ((res=match(ms, s, p)) == NULL)  /* match failed? */
+    ms->level--;  /* undo capture */
+  return res;
+}
+
+
+static const char *end_capture (MatchState *ms, const char *s,
+                                  const char *p) {
+  int l = capture_to_close(ms);
+  const char *res;
+  ms->capture[l].len = s - ms->capture[l].init;  /* close capture */
+  if ((res = match(ms, s, p)) == NULL)  /* match failed? */
+    ms->capture[l].len = CAP_UNFINISHED;  /* undo capture */
+  return res;
+}
+
+
+static const char *match_capture (MatchState *ms, const char *s, int l) {
+  size_t len;
+  l = check_capture(ms, l);
+  len = ms->capture[l].len;
+  if ((size_t)(ms->src_end-s) >= len &&
+      memcmp(ms->capture[l].init, s, len) == 0)
+    return s+len;
+  else return NULL;
+}
+
+
+static const char *match (MatchState *ms, const char *s, const char *p) {
+  init: /* using goto's to optimize tail recursion */
+  switch (*p) {
+    case '(': {  /* start capture */
+      if (*(p+1) == ')')  /* position capture? */
+        return start_capture(ms, s, p+2, CAP_POSITION);
+      else
+        return start_capture(ms, s, p+1, CAP_UNFINISHED);
+    }
+    case ')': {  /* end capture */
+      return end_capture(ms, s, p+1);
+    }
+    case L_ESC: {
+      switch (*(p+1)) {
+        case 'b': {  /* balanced string? */
+          s = matchbalance(ms, s, p+2);
+          if (s == NULL) return NULL;
+          p+=4; goto init;  /* else return match(ms, s, p+4); */
+        }
+        case 'f': {  /* frontier? */
+          const char *ep; char previous;
+          p += 2;
+          if (*p != '[')
+            luaL_error(ms->L, "missing " LUA_QL("[") " after "
+                               LUA_QL("%%f") " in pattern");
+          ep = classend(ms, p);  /* points to what is next */
+          previous = (s == ms->src_init) ? '\0' : *(s-1);
+          if (matchbracketclass(uchar(previous), p, ep-1) ||
+             !matchbracketclass(uchar(*s), p, ep-1)) return NULL;
+          p=ep; goto init;  /* else return match(ms, s, ep); */
+        }
+        default: {
+          if (isdigit(uchar(*(p+1)))) {  /* capture results (%0-%9)? */
+            s = match_capture(ms, s, uchar(*(p+1)));
+            if (s == NULL) return NULL;
+            p+=2; goto init;  /* else return match(ms, s, p+2) */
+          }
+          goto dflt;  /* case default */
+        }
+      }
+    }
+    case '\0': {  /* end of pattern */
+      return s;  /* match succeeded */
+    }
+    case '$': {
+      if (*(p+1) == '\0')  /* is the `$' the last char in pattern? */
+        return (s == ms->src_end) ? s : NULL;  /* check end of string */
+      else goto dflt;
+    }
+    default: dflt: {  /* it is a pattern item */
+      const char *ep = classend(ms, p);  /* points to what is next */
+      int m = s<ms->src_end && singlematch(uchar(*s), p, ep);
+      switch (*ep) {
+        case '?': {  /* optional */
+          const char *res;
+          if (m && ((res=match(ms, s+1, ep+1)) != NULL))
+            return res;
+          p=ep+1; goto init;  /* else return match(ms, s, ep+1); */
+        }
+        case '*': {  /* 0 or more repetitions */
+          return max_expand(ms, s, p, ep);
+        }
+        case '+': {  /* 1 or more repetitions */
+          return (m ? max_expand(ms, s+1, p, ep) : NULL);
+        }
+        case '-': {  /* 0 or more repetitions (minimum) */
+          return min_expand(ms, s, p, ep);
+        }
+        default: {
+          if (!m) return NULL;
+          s++; p=ep; goto init;  /* else return match(ms, s+1, ep); */
+        }
+      }
+    }
+  }
+}
+
+
+
+static const char *lmemfind (const char *s1, size_t l1,
+                               const char *s2, size_t l2) {
+  if (l2 == 0) return s1;  /* empty strings are everywhere */
+  else if (l2 > l1) return NULL;  /* avoids a negative `l1' */
+  else {
+    const char *init;  /* to search for a `*s2' inside `s1' */
+    l2--;  /* 1st char will be checked by `memchr' */
+    l1 = l1-l2;  /* `s2' cannot be found after that */
+    while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
+      init++;   /* 1st char is already checked */
+      if (memcmp(init, s2+1, l2) == 0)
+        return init-1;
+      else {  /* correct `l1' and `s1' to try again */
+        l1 -= init-s1;
+        s1 = init;
+      }
+    }
+    return NULL;  /* not found */
+  }
+}
+
+
+static void push_onecapture (MatchState *ms, int i, const char *s,
+                                                    const char *e) {
+  if (i >= ms->level) {
+    if (i == 0)  /* ms->level == 0, too */
+      lua_pushlstring(ms->L, s, e - s);  /* add whole match */
+    else
+      luaL_error(ms->L, "invalid capture index");
+  }
+  else {
+    ptrdiff_t l = ms->capture[i].len;
+    if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
+    if (l == CAP_POSITION)
+      lua_pushinteger(ms->L, ms->capture[i].init - ms->src_init + 1);
+    else
+      lua_pushlstring(ms->L, ms->capture[i].init, l);
+  }
+}
+
+
+static int push_captures (MatchState *ms, const char *s, const char *e) {
+  int i;
+  int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
+  luaL_checkstack(ms->L, nlevels, "too many captures");
+  for (i = 0; i < nlevels; i++)
+    push_onecapture(ms, i, s, e);
+  return nlevels;  /* number of strings pushed */
+}
+
+
+static int str_find_aux (lua_State *L, int find) {
+  size_t l1, l2;
+  const char *s = luaL_checklstring(L, 1, &l1);
+  const char *p = luaL_checklstring(L, 2, &l2);
+  ptrdiff_t init = posrelat(luaL_optinteger(L, 3, 1), l1) - 1;
+  if (init < 0) init = 0;
+  else if ((size_t)(init) > l1) init = (ptrdiff_t)l1;
+  if (find && (lua_toboolean(L, 4) ||  /* explicit request? */
+      strpbrk(p, SPECIALS) == NULL)) {  /* or no special characters? */
+    /* do a plain search */
+    const char *s2 = lmemfind(s+init, l1-init, p, l2);
+    if (s2) {
+      lua_pushinteger(L, s2-s+1);
+      lua_pushinteger(L, s2-s+l2);
+      return 2;
+    }
+  }
+  else {
+    MatchState ms;
+    int anchor = (*p == '^') ? (p++, 1) : 0;
+    const char *s1=s+init;
+    ms.L = L;
+    ms.src_init = s;
+    ms.src_end = s+l1;
+    do {
+      const char *res;
+      ms.level = 0;
+      if ((res=match(&ms, s1, p)) != NULL) {
+        if (find) {
+          lua_pushinteger(L, s1-s+1);  /* start */
+          lua_pushinteger(L, res-s);   /* end */
+          return push_captures(&ms, NULL, 0) + 2;
+        }
+        else
+          return push_captures(&ms, s1, res);
+      }
+    } while (s1++ < ms.src_end && !anchor);
+  }
+  lua_pushnil(L);  /* not found */
+  return 1;
+}
+
+
+static int str_find (lua_State *L) {
+  return str_find_aux(L, 1);
+}
+
+
+static int str_match (lua_State *L) {
+  return str_find_aux(L, 0);
+}
+
+
+static int gmatch_aux (lua_State *L) {
+  MatchState ms;
+  size_t ls;
+  const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
+  const char *p = lua_tostring(L, lua_upvalueindex(2));
+  const char *src;
+  ms.L = L;
+  ms.src_init = s;
+  ms.src_end = s+ls;
+  for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3));
+       src <= ms.src_end;
+       src++) {
+    const char *e;
+    ms.level = 0;
+    if ((e = match(&ms, src, p)) != NULL) {
+      lua_Integer newstart = e-s;
+      if (e == src) newstart++;  /* empty match? go at least one position */
+      lua_pushinteger(L, newstart);
+      lua_replace(L, lua_upvalueindex(3));
+      return push_captures(&ms, src, e);
+    }
+  }
+  return 0;  /* not found */
+}
+
+
+static int gmatch (lua_State *L) {
+  luaL_checkstring(L, 1);
+  luaL_checkstring(L, 2);
+  lua_settop(L, 2);
+  lua_pushinteger(L, 0);
+  lua_pushcclosure(L, gmatch_aux, 3);
+  return 1;
+}
+
+
+static int gfind_nodef (lua_State *L) {
+  return luaL_error(L, LUA_QL("string.gfind") " was renamed to "
+                       LUA_QL("string.gmatch"));
+}
+
+
+static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
+                                                   const char *e) {
+  size_t l, i;
+  const char *news = lua_tolstring(ms->L, 3, &l);
+  for (i = 0; i < l; i++) {
+    if (news[i] != L_ESC)
+      luaL_addchar(b, news[i]);
+    else {
+      i++;  /* skip ESC */
+      if (!isdigit(uchar(news[i])))
+        luaL_addchar(b, news[i]);
+      else if (news[i] == '0')
+          luaL_addlstring(b, s, e - s);
+      else {
+        push_onecapture(ms, news[i] - '1', s, e);
+        luaL_addvalue(b);  /* add capture to accumulated result */
+      }
+    }
+  }
+}
+
+
+static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
+                                                       const char *e) {
+  lua_State *L = ms->L;
+  switch (lua_type(L, 3)) {
+    case LUA_TNUMBER:
+    case LUA_TSTRING: {
+      add_s(ms, b, s, e);
+      return;
+    }
+    case LUA_TFUNCTION: {
+      int n;
+      lua_pushvalue(L, 3);
+      n = push_captures(ms, s, e);
+      lua_call(L, n, 1);
+      break;
+    }
+    case LUA_TTABLE: {
+      push_onecapture(ms, 0, s, e);
+      lua_gettable(L, 3);
+      break;
+    }
+  }
+  if (!lua_toboolean(L, -1)) {  /* nil or false? */
+    lua_pop(L, 1);
+    lua_pushlstring(L, s, e - s);  /* keep original text */
+  }
+  else if (!lua_isstring(L, -1))
+    luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1)); 
+  luaL_addvalue(b);  /* add result to accumulator */
+}
+
+
+static int str_gsub (lua_State *L) {
+  size_t srcl;
+  const char *src = luaL_checklstring(L, 1, &srcl);
+  const char *p = luaL_checkstring(L, 2);
+  int  tr = lua_type(L, 3);
+  int max_s = luaL_optint(L, 4, srcl+1);
+  int anchor = (*p == '^') ? (p++, 1) : 0;
+  int n = 0;
+  MatchState ms;
+  luaL_Buffer b;
+  luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
+                   tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
+                      "string/function/table expected");
+  luaL_buffinit(L, &b);
+  ms.L = L;
+  ms.src_init = src;
+  ms.src_end = src+srcl;
+  while (n < max_s) {
+    const char *e;
+    ms.level = 0;
+    e = match(&ms, src, p);
+    if (e) {
+      n++;
+      add_value(&ms, &b, src, e);
+    }
+    if (e && e>src) /* non empty match? */
+      src = e;  /* skip it */
+    else if (src < ms.src_end)
+      luaL_addchar(&b, *src++);
+    else break;
+    if (anchor) break;
+  }
+  luaL_addlstring(&b, src, ms.src_end-src);
+  luaL_pushresult(&b);
+  lua_pushinteger(L, n);  /* number of substitutions */
+  return 2;
+}
+
+/* }====================================================== */
+
+
+/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
+#define MAX_ITEM	512
+/* valid flags in a format specification */
+#define FLAGS	"-+ #0"
+/*
+** maximum size of each format specification (such as '%-099.99d')
+** (+10 accounts for %99.99x plus margin of error)
+*/
+#define MAX_FORMAT	(sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10)
+
+
+static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
+  size_t l;
+  const char *s = luaL_checklstring(L, arg, &l);
+  luaL_addchar(b, '"');
+  while (l--) {
+    switch (*s) {
+      case '"': case '\\': case '\n': {
+        luaL_addchar(b, '\\');
+        luaL_addchar(b, *s);
+        break;
+      }
+      case '\r': {
+        luaL_addlstring(b, "\\r", 2);
+        break;
+      }
+      case '\0': {
+        luaL_addlstring(b, "\\000", 4);
+        break;
+      }
+      default: {
+        luaL_addchar(b, *s);
+        break;
+      }
+    }
+    s++;
+  }
+  luaL_addchar(b, '"');
+}
+
+static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
+  const char *p = strfrmt;
+  while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++;  /* skip flags */
+  if ((size_t)(p - strfrmt) >= sizeof(FLAGS))
+    luaL_error(L, "invalid format (repeated flags)");
+  if (isdigit(uchar(*p))) p++;  /* skip width */
+  if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
+  if (*p == '.') {
+    p++;
+    if (isdigit(uchar(*p))) p++;  /* skip precision */
+    if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
+  }
+  if (isdigit(uchar(*p)))
+    luaL_error(L, "invalid format (width or precision too long)");
+  *(form++) = '%';
+  strncpy(form, strfrmt, p - strfrmt + 1);
+  form += p - strfrmt + 1;
+  *form = '\0';
+  return p;
+}
+
+
+static void addintlen (char *form) {
+  size_t l = strlen(form);
+  char spec = form[l - 1];
+  strcpy(form + l - 1, LUA_INTFRMLEN);
+  form[l + sizeof(LUA_INTFRMLEN) - 2] = spec;
+  form[l + sizeof(LUA_INTFRMLEN) - 1] = '\0';
+}
+
+
+static int str_format (lua_State *L) {
+  int top = lua_gettop(L);
+  int arg = 1;
+  size_t sfl;
+  const char *strfrmt = luaL_checklstring(L, arg, &sfl);
+  const char *strfrmt_end = strfrmt+sfl;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  while (strfrmt < strfrmt_end) {
+    if (*strfrmt != L_ESC)
+      luaL_addchar(&b, *strfrmt++);
+    else if (*++strfrmt == L_ESC)
+      luaL_addchar(&b, *strfrmt++);  /* %% */
+    else { /* format item */
+      char form[MAX_FORMAT];  /* to store the format (`%...') */
+      char buff[MAX_ITEM];  /* to store the formatted item */
+      if (++arg > top)
+        luaL_argerror(L, arg, "no value");
+      strfrmt = scanformat(L, strfrmt, form);
+      switch (*strfrmt++) {
+        case 'c': {
+          sprintf(buff, form, (int)luaL_checknumber(L, arg));
+          break;
+        }
+        case 'd':  case 'i': {
+          addintlen(form);
+          sprintf(buff, form, (LUA_INTFRM_T)luaL_checknumber(L, arg));
+          break;
+        }
+        case 'o':  case 'u':  case 'x':  case 'X': {
+          addintlen(form);
+          sprintf(buff, form, (unsigned LUA_INTFRM_T)luaL_checknumber(L, arg));
+          break;
+        }
+        case 'e':  case 'E': case 'f':
+        case 'g': case 'G': {
+          sprintf(buff, form, (double)luaL_checknumber(L, arg));
+          break;
+        }
+        case 'q': {
+          addquoted(L, &b, arg);
+          continue;  /* skip the 'addsize' at the end */
+        }
+        case 's': {
+          size_t l;
+          const char *s = luaL_checklstring(L, arg, &l);
+          if (!strchr(form, '.') && l >= 100) {
+            /* no precision and string is too long to be formatted;
+               keep original string */
+            lua_pushvalue(L, arg);
+            luaL_addvalue(&b);
+            continue;  /* skip the `addsize' at the end */
+          }
+          else {
+            sprintf(buff, form, s);
+            break;
+          }
+        }
+        default: {  /* also treat cases `pnLlh' */
+          return luaL_error(L, "invalid option " LUA_QL("%%%c") " to "
+                               LUA_QL("format"), *(strfrmt - 1));
+        }
+      }
+      luaL_addlstring(&b, buff, strlen(buff));
+    }
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static const luaL_Reg strlib[] = {
+  {"byte", str_byte},
+  {"char", str_char},
+  {"dump", str_dump},
+  {"find", str_find},
+  {"format", str_format},
+  {"gfind", gfind_nodef},
+  {"gmatch", gmatch},
+  {"gsub", str_gsub},
+  {"len", str_len},
+  {"lower", str_lower},
+  {"match", str_match},
+  {"rep", str_rep},
+  {"reverse", str_reverse},
+  {"sub", str_sub},
+  {"upper", str_upper},
+  {NULL, NULL}
+};
+
+
+static void createmetatable (lua_State *L) {
+  lua_createtable(L, 0, 1);  /* create metatable for strings */
+  lua_pushliteral(L, "");  /* dummy string */
+  lua_pushvalue(L, -2);
+  lua_setmetatable(L, -2);  /* set string metatable */
+  lua_pop(L, 1);  /* pop dummy string */
+  lua_pushvalue(L, -2);  /* string library... */
+  lua_setfield(L, -2, "__index");  /* ...is the __index metamethod */
+  lua_pop(L, 1);  /* pop metatable */
+}
+
+
+/*
+** Open string library
+*/
+LUALIB_API int luaopen_string (lua_State *L) {
+  luaL_register(L, LUA_STRLIBNAME, strlib);
+#if defined(LUA_COMPAT_GFIND)
+  lua_getfield(L, -1, "gmatch");
+  lua_setfield(L, -2, "gfind");
+#endif
+  createmetatable(L);
+  return 1;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/ltable.c b/third_party/lua-src/lua-5.1.5/ltable.c
new file mode 100644
index 00000000..ec84f4fa
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ltable.c
@@ -0,0 +1,588 @@
+/*
+** $Id: ltable.c,v 2.32.1.2 2007/12/28 15:32:23 roberto Exp $
+** Lua tables (hash)
+** See Copyright Notice in lua.h
+*/
+
+
+/*
+** Implementation of tables (aka arrays, objects, or hash tables).
+** Tables keep its elements in two parts: an array part and a hash part.
+** Non-negative integer keys are all candidates to be kept in the array
+** part. The actual size of the array is the largest `n' such that at
+** least half the slots between 0 and n are in use.
+** Hash uses a mix of chained scatter table with Brent's variation.
+** A main invariant of these tables is that, if an element is not
+** in its main position (i.e. the `original' position that its hash gives
+** to it), then the colliding element is in its own main position.
+** Hence even when the load factor reaches 100%, performance remains good.
+*/
+
+#include <math.h>
+#include <string.h>
+
+#define ltable_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "ltable.h"
+
+
+/*
+** max size of array part is 2^MAXBITS
+*/
+#if LUAI_BITSINT > 26
+#define MAXBITS		26
+#else
+#define MAXBITS		(LUAI_BITSINT-2)
+#endif
+
+#define MAXASIZE	(1 << MAXBITS)
+
+
+#define hashpow2(t,n)      (gnode(t, lmod((n), sizenode(t))))
+  
+#define hashstr(t,str)  hashpow2(t, (str)->tsv.hash)
+#define hashboolean(t,p)        hashpow2(t, p)
+
+
+/*
+** for some types, it is better to avoid modulus by power of 2, as
+** they tend to have many 2 factors.
+*/
+#define hashmod(t,n)	(gnode(t, ((n) % ((sizenode(t)-1)|1))))
+
+
+#define hashpointer(t,p)	hashmod(t, IntPoint(p))
+
+
+/*
+** number of ints inside a lua_Number
+*/
+#define numints		cast_int(sizeof(lua_Number)/sizeof(int))
+
+
+
+#define dummynode		(&dummynode_)
+
+static const Node dummynode_ = {
+  {{NULL}, LUA_TNIL},  /* value */
+  {{{NULL}, LUA_TNIL, NULL}}  /* key */
+};
+
+
+/*
+** hash for lua_Numbers
+*/
+static Node *hashnum (const Table *t, lua_Number n) {
+  unsigned int a[numints];
+  int i;
+  if (luai_numeq(n, 0))  /* avoid problems with -0 */
+    return gnode(t, 0);
+  memcpy(a, &n, sizeof(a));
+  for (i = 1; i < numints; i++) a[0] += a[i];
+  return hashmod(t, a[0]);
+}
+
+
+
+/*
+** returns the `main' position of an element in a table (that is, the index
+** of its hash value)
+*/
+static Node *mainposition (const Table *t, const TValue *key) {
+  switch (ttype(key)) {
+    case LUA_TNUMBER:
+      return hashnum(t, nvalue(key));
+    case LUA_TSTRING:
+      return hashstr(t, rawtsvalue(key));
+    case LUA_TBOOLEAN:
+      return hashboolean(t, bvalue(key));
+    case LUA_TLIGHTUSERDATA:
+      return hashpointer(t, pvalue(key));
+    default:
+      return hashpointer(t, gcvalue(key));
+  }
+}
+
+
+/*
+** returns the index for `key' if `key' is an appropriate key to live in
+** the array part of the table, -1 otherwise.
+*/
+static int arrayindex (const TValue *key) {
+  if (ttisnumber(key)) {
+    lua_Number n = nvalue(key);
+    int k;
+    lua_number2int(k, n);
+    if (luai_numeq(cast_num(k), n))
+      return k;
+  }
+  return -1;  /* `key' did not match some condition */
+}
+
+
+/*
+** returns the index of a `key' for table traversals. First goes all
+** elements in the array part, then elements in the hash part. The
+** beginning of a traversal is signalled by -1.
+*/
+static int findindex (lua_State *L, Table *t, StkId key) {
+  int i;
+  if (ttisnil(key)) return -1;  /* first iteration */
+  i = arrayindex(key);
+  if (0 < i && i <= t->sizearray)  /* is `key' inside array part? */
+    return i-1;  /* yes; that's the index (corrected to C) */
+  else {
+    Node *n = mainposition(t, key);
+    do {  /* check whether `key' is somewhere in the chain */
+      /* key may be dead already, but it is ok to use it in `next' */
+      if (luaO_rawequalObj(key2tval(n), key) ||
+            (ttype(gkey(n)) == LUA_TDEADKEY && iscollectable(key) &&
+             gcvalue(gkey(n)) == gcvalue(key))) {
+        i = cast_int(n - gnode(t, 0));  /* key index in hash table */
+        /* hash elements are numbered after array ones */
+        return i + t->sizearray;
+      }
+      else n = gnext(n);
+    } while (n);
+    luaG_runerror(L, "invalid key to " LUA_QL("next"));  /* key not found */
+    return 0;  /* to avoid warnings */
+  }
+}
+
+
+int luaH_next (lua_State *L, Table *t, StkId key) {
+  int i = findindex(L, t, key);  /* find original element */
+  for (i++; i < t->sizearray; i++) {  /* try first array part */
+    if (!ttisnil(&t->array[i])) {  /* a non-nil value? */
+      setnvalue(key, cast_num(i+1));
+      setobj2s(L, key+1, &t->array[i]);
+      return 1;
+    }
+  }
+  for (i -= t->sizearray; i < sizenode(t); i++) {  /* then hash part */
+    if (!ttisnil(gval(gnode(t, i)))) {  /* a non-nil value? */
+      setobj2s(L, key, key2tval(gnode(t, i)));
+      setobj2s(L, key+1, gval(gnode(t, i)));
+      return 1;
+    }
+  }
+  return 0;  /* no more elements */
+}
+
+
+/*
+** {=============================================================
+** Rehash
+** ==============================================================
+*/
+
+
+static int computesizes (int nums[], int *narray) {
+  int i;
+  int twotoi;  /* 2^i */
+  int a = 0;  /* number of elements smaller than 2^i */
+  int na = 0;  /* number of elements to go to array part */
+  int n = 0;  /* optimal size for array part */
+  for (i = 0, twotoi = 1; twotoi/2 < *narray; i++, twotoi *= 2) {
+    if (nums[i] > 0) {
+      a += nums[i];
+      if (a > twotoi/2) {  /* more than half elements present? */
+        n = twotoi;  /* optimal size (till now) */
+        na = a;  /* all elements smaller than n will go to array part */
+      }
+    }
+    if (a == *narray) break;  /* all elements already counted */
+  }
+  *narray = n;
+  lua_assert(*narray/2 <= na && na <= *narray);
+  return na;
+}
+
+
+static int countint (const TValue *key, int *nums) {
+  int k = arrayindex(key);
+  if (0 < k && k <= MAXASIZE) {  /* is `key' an appropriate array index? */
+    nums[ceillog2(k)]++;  /* count as such */
+    return 1;
+  }
+  else
+    return 0;
+}
+
+
+static int numusearray (const Table *t, int *nums) {
+  int lg;
+  int ttlg;  /* 2^lg */
+  int ause = 0;  /* summation of `nums' */
+  int i = 1;  /* count to traverse all array keys */
+  for (lg=0, ttlg=1; lg<=MAXBITS; lg++, ttlg*=2) {  /* for each slice */
+    int lc = 0;  /* counter */
+    int lim = ttlg;
+    if (lim > t->sizearray) {
+      lim = t->sizearray;  /* adjust upper limit */
+      if (i > lim)
+        break;  /* no more elements to count */
+    }
+    /* count elements in range (2^(lg-1), 2^lg] */
+    for (; i <= lim; i++) {
+      if (!ttisnil(&t->array[i-1]))
+        lc++;
+    }
+    nums[lg] += lc;
+    ause += lc;
+  }
+  return ause;
+}
+
+
+static int numusehash (const Table *t, int *nums, int *pnasize) {
+  int totaluse = 0;  /* total number of elements */
+  int ause = 0;  /* summation of `nums' */
+  int i = sizenode(t);
+  while (i--) {
+    Node *n = &t->node[i];
+    if (!ttisnil(gval(n))) {
+      ause += countint(key2tval(n), nums);
+      totaluse++;
+    }
+  }
+  *pnasize += ause;
+  return totaluse;
+}
+
+
+static void setarrayvector (lua_State *L, Table *t, int size) {
+  int i;
+  luaM_reallocvector(L, t->array, t->sizearray, size, TValue);
+  for (i=t->sizearray; i<size; i++)
+     setnilvalue(&t->array[i]);
+  t->sizearray = size;
+}
+
+
+static void setnodevector (lua_State *L, Table *t, int size) {
+  int lsize;
+  if (size == 0) {  /* no elements to hash part? */
+    t->node = cast(Node *, dummynode);  /* use common `dummynode' */
+    lsize = 0;
+  }
+  else {
+    int i;
+    lsize = ceillog2(size);
+    if (lsize > MAXBITS)
+      luaG_runerror(L, "table overflow");
+    size = twoto(lsize);
+    t->node = luaM_newvector(L, size, Node);
+    for (i=0; i<size; i++) {
+      Node *n = gnode(t, i);
+      gnext(n) = NULL;
+      setnilvalue(gkey(n));
+      setnilvalue(gval(n));
+    }
+  }
+  t->lsizenode = cast_byte(lsize);
+  t->lastfree = gnode(t, size);  /* all positions are free */
+}
+
+
+static void resize (lua_State *L, Table *t, int nasize, int nhsize) {
+  int i;
+  int oldasize = t->sizearray;
+  int oldhsize = t->lsizenode;
+  Node *nold = t->node;  /* save old hash ... */
+  if (nasize > oldasize)  /* array part must grow? */
+    setarrayvector(L, t, nasize);
+  /* create new hash part with appropriate size */
+  setnodevector(L, t, nhsize);  
+  if (nasize < oldasize) {  /* array part must shrink? */
+    t->sizearray = nasize;
+    /* re-insert elements from vanishing slice */
+    for (i=nasize; i<oldasize; i++) {
+      if (!ttisnil(&t->array[i]))
+        setobjt2t(L, luaH_setnum(L, t, i+1), &t->array[i]);
+    }
+    /* shrink array */
+    luaM_reallocvector(L, t->array, oldasize, nasize, TValue);
+  }
+  /* re-insert elements from hash part */
+  for (i = twoto(oldhsize) - 1; i >= 0; i--) {
+    Node *old = nold+i;
+    if (!ttisnil(gval(old)))
+      setobjt2t(L, luaH_set(L, t, key2tval(old)), gval(old));
+  }
+  if (nold != dummynode)
+    luaM_freearray(L, nold, twoto(oldhsize), Node);  /* free old array */
+}
+
+
+void luaH_resizearray (lua_State *L, Table *t, int nasize) {
+  int nsize = (t->node == dummynode) ? 0 : sizenode(t);
+  resize(L, t, nasize, nsize);
+}
+
+
+static void rehash (lua_State *L, Table *t, const TValue *ek) {
+  int nasize, na;
+  int nums[MAXBITS+1];  /* nums[i] = number of keys between 2^(i-1) and 2^i */
+  int i;
+  int totaluse;
+  for (i=0; i<=MAXBITS; i++) nums[i] = 0;  /* reset counts */
+  nasize = numusearray(t, nums);  /* count keys in array part */
+  totaluse = nasize;  /* all those keys are integer keys */
+  totaluse += numusehash(t, nums, &nasize);  /* count keys in hash part */
+  /* count extra key */
+  nasize += countint(ek, nums);
+  totaluse++;
+  /* compute new size for array part */
+  na = computesizes(nums, &nasize);
+  /* resize the table to new computed sizes */
+  resize(L, t, nasize, totaluse - na);
+}
+
+
+
+/*
+** }=============================================================
+*/
+
+
+Table *luaH_new (lua_State *L, int narray, int nhash) {
+  Table *t = luaM_new(L, Table);
+  luaC_link(L, obj2gco(t), LUA_TTABLE);
+  t->metatable = NULL;
+  t->flags = cast_byte(~0);
+  /* temporary values (kept only if some malloc fails) */
+  t->array = NULL;
+  t->sizearray = 0;
+  t->lsizenode = 0;
+  t->node = cast(Node *, dummynode);
+  setarrayvector(L, t, narray);
+  setnodevector(L, t, nhash);
+  return t;
+}
+
+
+void luaH_free (lua_State *L, Table *t) {
+  if (t->node != dummynode)
+    luaM_freearray(L, t->node, sizenode(t), Node);
+  luaM_freearray(L, t->array, t->sizearray, TValue);
+  luaM_free(L, t);
+}
+
+
+static Node *getfreepos (Table *t) {
+  while (t->lastfree-- > t->node) {
+    if (ttisnil(gkey(t->lastfree)))
+      return t->lastfree;
+  }
+  return NULL;  /* could not find a free place */
+}
+
+
+
+/*
+** inserts a new key into a hash table; first, check whether key's main 
+** position is free. If not, check whether colliding node is in its main 
+** position or not: if it is not, move colliding node to an empty place and 
+** put new key in its main position; otherwise (colliding node is in its main 
+** position), new key goes to an empty position. 
+*/
+static TValue *newkey (lua_State *L, Table *t, const TValue *key) {
+  Node *mp = mainposition(t, key);
+  if (!ttisnil(gval(mp)) || mp == dummynode) {
+    Node *othern;
+    Node *n = getfreepos(t);  /* get a free place */
+    if (n == NULL) {  /* cannot find a free place? */
+      rehash(L, t, key);  /* grow table */
+      return luaH_set(L, t, key);  /* re-insert key into grown table */
+    }
+    lua_assert(n != dummynode);
+    othern = mainposition(t, key2tval(mp));
+    if (othern != mp) {  /* is colliding node out of its main position? */
+      /* yes; move colliding node into free position */
+      while (gnext(othern) != mp) othern = gnext(othern);  /* find previous */
+      gnext(othern) = n;  /* redo the chain with `n' in place of `mp' */
+      *n = *mp;  /* copy colliding node into free pos. (mp->next also goes) */
+      gnext(mp) = NULL;  /* now `mp' is free */
+      setnilvalue(gval(mp));
+    }
+    else {  /* colliding node is in its own main position */
+      /* new node will go into free position */
+      gnext(n) = gnext(mp);  /* chain new position */
+      gnext(mp) = n;
+      mp = n;
+    }
+  }
+  gkey(mp)->value = key->value; gkey(mp)->tt = key->tt;
+  luaC_barriert(L, t, key);
+  lua_assert(ttisnil(gval(mp)));
+  return gval(mp);
+}
+
+
+/*
+** search function for integers
+*/
+const TValue *luaH_getnum (Table *t, int key) {
+  /* (1 <= key && key <= t->sizearray) */
+  if (cast(unsigned int, key-1) < cast(unsigned int, t->sizearray))
+    return &t->array[key-1];
+  else {
+    lua_Number nk = cast_num(key);
+    Node *n = hashnum(t, nk);
+    do {  /* check whether `key' is somewhere in the chain */
+      if (ttisnumber(gkey(n)) && luai_numeq(nvalue(gkey(n)), nk))
+        return gval(n);  /* that's it */
+      else n = gnext(n);
+    } while (n);
+    return luaO_nilobject;
+  }
+}
+
+
+/*
+** search function for strings
+*/
+const TValue *luaH_getstr (Table *t, TString *key) {
+  Node *n = hashstr(t, key);
+  do {  /* check whether `key' is somewhere in the chain */
+    if (ttisstring(gkey(n)) && rawtsvalue(gkey(n)) == key)
+      return gval(n);  /* that's it */
+    else n = gnext(n);
+  } while (n);
+  return luaO_nilobject;
+}
+
+
+/*
+** main search function
+*/
+const TValue *luaH_get (Table *t, const TValue *key) {
+  switch (ttype(key)) {
+    case LUA_TNIL: return luaO_nilobject;
+    case LUA_TSTRING: return luaH_getstr(t, rawtsvalue(key));
+    case LUA_TNUMBER: {
+      int k;
+      lua_Number n = nvalue(key);
+      lua_number2int(k, n);
+      if (luai_numeq(cast_num(k), nvalue(key))) /* index is int? */
+        return luaH_getnum(t, k);  /* use specialized version */
+      /* else go through */
+    }
+    default: {
+      Node *n = mainposition(t, key);
+      do {  /* check whether `key' is somewhere in the chain */
+        if (luaO_rawequalObj(key2tval(n), key))
+          return gval(n);  /* that's it */
+        else n = gnext(n);
+      } while (n);
+      return luaO_nilobject;
+    }
+  }
+}
+
+
+TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
+  const TValue *p = luaH_get(t, key);
+  t->flags = 0;
+  if (p != luaO_nilobject)
+    return cast(TValue *, p);
+  else {
+    if (ttisnil(key)) luaG_runerror(L, "table index is nil");
+    else if (ttisnumber(key) && luai_numisnan(nvalue(key)))
+      luaG_runerror(L, "table index is NaN");
+    return newkey(L, t, key);
+  }
+}
+
+
+TValue *luaH_setnum (lua_State *L, Table *t, int key) {
+  const TValue *p = luaH_getnum(t, key);
+  if (p != luaO_nilobject)
+    return cast(TValue *, p);
+  else {
+    TValue k;
+    setnvalue(&k, cast_num(key));
+    return newkey(L, t, &k);
+  }
+}
+
+
+TValue *luaH_setstr (lua_State *L, Table *t, TString *key) {
+  const TValue *p = luaH_getstr(t, key);
+  if (p != luaO_nilobject)
+    return cast(TValue *, p);
+  else {
+    TValue k;
+    setsvalue(L, &k, key);
+    return newkey(L, t, &k);
+  }
+}
+
+
+static int unbound_search (Table *t, unsigned int j) {
+  unsigned int i = j;  /* i is zero or a present index */
+  j++;
+  /* find `i' and `j' such that i is present and j is not */
+  while (!ttisnil(luaH_getnum(t, j))) {
+    i = j;
+    j *= 2;
+    if (j > cast(unsigned int, MAX_INT)) {  /* overflow? */
+      /* table was built with bad purposes: resort to linear search */
+      i = 1;
+      while (!ttisnil(luaH_getnum(t, i))) i++;
+      return i - 1;
+    }
+  }
+  /* now do a binary search between them */
+  while (j - i > 1) {
+    unsigned int m = (i+j)/2;
+    if (ttisnil(luaH_getnum(t, m))) j = m;
+    else i = m;
+  }
+  return i;
+}
+
+
+/*
+** Try to find a boundary in table `t'. A `boundary' is an integer index
+** such that t[i] is non-nil and t[i+1] is nil (and 0 if t[1] is nil).
+*/
+int luaH_getn (Table *t) {
+  unsigned int j = t->sizearray;
+  if (j > 0 && ttisnil(&t->array[j - 1])) {
+    /* there is a boundary in the array part: (binary) search for it */
+    unsigned int i = 0;
+    while (j - i > 1) {
+      unsigned int m = (i+j)/2;
+      if (ttisnil(&t->array[m - 1])) j = m;
+      else i = m;
+    }
+    return i;
+  }
+  /* else must find a boundary in hash part */
+  else if (t->node == dummynode)  /* hash part is empty? */
+    return j;  /* that is easy... */
+  else return unbound_search(t, j);
+}
+
+
+
+#if defined(LUA_DEBUG)
+
+Node *luaH_mainposition (const Table *t, const TValue *key) {
+  return mainposition(t, key);
+}
+
+int luaH_isdummy (Node *n) { return n == dummynode; }
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/ltable.h b/third_party/lua-src/lua-5.1.5/ltable.h
new file mode 100644
index 00000000..f5b9d5ea
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ltable.h
@@ -0,0 +1,40 @@
+/*
+** $Id: ltable.h,v 2.10.1.1 2007/12/27 13:02:25 roberto Exp $
+** Lua tables (hash)
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ltable_h
+#define ltable_h
+
+#include "lobject.h"
+
+
+#define gnode(t,i)	(&(t)->node[i])
+#define gkey(n)		(&(n)->i_key.nk)
+#define gval(n)		(&(n)->i_val)
+#define gnext(n)	((n)->i_key.nk.next)
+
+#define key2tval(n)	(&(n)->i_key.tvk)
+
+
+LUAI_FUNC const TValue *luaH_getnum (Table *t, int key);
+LUAI_FUNC TValue *luaH_setnum (lua_State *L, Table *t, int key);
+LUAI_FUNC const TValue *luaH_getstr (Table *t, TString *key);
+LUAI_FUNC TValue *luaH_setstr (lua_State *L, Table *t, TString *key);
+LUAI_FUNC const TValue *luaH_get (Table *t, const TValue *key);
+LUAI_FUNC TValue *luaH_set (lua_State *L, Table *t, const TValue *key);
+LUAI_FUNC Table *luaH_new (lua_State *L, int narray, int lnhash);
+LUAI_FUNC void luaH_resizearray (lua_State *L, Table *t, int nasize);
+LUAI_FUNC void luaH_free (lua_State *L, Table *t);
+LUAI_FUNC int luaH_next (lua_State *L, Table *t, StkId key);
+LUAI_FUNC int luaH_getn (Table *t);
+
+
+#if defined(LUA_DEBUG)
+LUAI_FUNC Node *luaH_mainposition (const Table *t, const TValue *key);
+LUAI_FUNC int luaH_isdummy (Node *n);
+#endif
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/ltablib.c b/third_party/lua-src/lua-5.1.5/ltablib.c
new file mode 100644
index 00000000..b6d9cb4a
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ltablib.c
@@ -0,0 +1,287 @@
+/*
+** $Id: ltablib.c,v 1.38.1.3 2008/02/14 16:46:58 roberto Exp $
+** Library for Table Manipulation
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define ltablib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#define aux_getn(L,n)	(luaL_checktype(L, n, LUA_TTABLE), luaL_getn(L, n))
+
+
+static int foreachi (lua_State *L) {
+  int i;
+  int n = aux_getn(L, 1);
+  luaL_checktype(L, 2, LUA_TFUNCTION);
+  for (i=1; i <= n; i++) {
+    lua_pushvalue(L, 2);  /* function */
+    lua_pushinteger(L, i);  /* 1st argument */
+    lua_rawgeti(L, 1, i);  /* 2nd argument */
+    lua_call(L, 2, 1);
+    if (!lua_isnil(L, -1))
+      return 1;
+    lua_pop(L, 1);  /* remove nil result */
+  }
+  return 0;
+}
+
+
+static int foreach (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checktype(L, 2, LUA_TFUNCTION);
+  lua_pushnil(L);  /* first key */
+  while (lua_next(L, 1)) {
+    lua_pushvalue(L, 2);  /* function */
+    lua_pushvalue(L, -3);  /* key */
+    lua_pushvalue(L, -3);  /* value */
+    lua_call(L, 2, 1);
+    if (!lua_isnil(L, -1))
+      return 1;
+    lua_pop(L, 2);  /* remove value and result */
+  }
+  return 0;
+}
+
+
+static int maxn (lua_State *L) {
+  lua_Number max = 0;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushnil(L);  /* first key */
+  while (lua_next(L, 1)) {
+    lua_pop(L, 1);  /* remove value */
+    if (lua_type(L, -1) == LUA_TNUMBER) {
+      lua_Number v = lua_tonumber(L, -1);
+      if (v > max) max = v;
+    }
+  }
+  lua_pushnumber(L, max);
+  return 1;
+}
+
+
+static int getn (lua_State *L) {
+  lua_pushinteger(L, aux_getn(L, 1));
+  return 1;
+}
+
+
+static int setn (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+#ifndef luaL_setn
+  luaL_setn(L, 1, luaL_checkint(L, 2));
+#else
+  luaL_error(L, LUA_QL("setn") " is obsolete");
+#endif
+  lua_pushvalue(L, 1);
+  return 1;
+}
+
+
+static int tinsert (lua_State *L) {
+  int e = aux_getn(L, 1) + 1;  /* first empty element */
+  int pos;  /* where to insert new element */
+  switch (lua_gettop(L)) {
+    case 2: {  /* called with only 2 arguments */
+      pos = e;  /* insert new element at the end */
+      break;
+    }
+    case 3: {
+      int i;
+      pos = luaL_checkint(L, 2);  /* 2nd argument is the position */
+      if (pos > e) e = pos;  /* `grow' array if necessary */
+      for (i = e; i > pos; i--) {  /* move up elements */
+        lua_rawgeti(L, 1, i-1);
+        lua_rawseti(L, 1, i);  /* t[i] = t[i-1] */
+      }
+      break;
+    }
+    default: {
+      return luaL_error(L, "wrong number of arguments to " LUA_QL("insert"));
+    }
+  }
+  luaL_setn(L, 1, e);  /* new size */
+  lua_rawseti(L, 1, pos);  /* t[pos] = v */
+  return 0;
+}
+
+
+static int tremove (lua_State *L) {
+  int e = aux_getn(L, 1);
+  int pos = luaL_optint(L, 2, e);
+  if (!(1 <= pos && pos <= e))  /* position is outside bounds? */
+   return 0;  /* nothing to remove */
+  luaL_setn(L, 1, e - 1);  /* t.n = n-1 */
+  lua_rawgeti(L, 1, pos);  /* result = t[pos] */
+  for ( ;pos<e; pos++) {
+    lua_rawgeti(L, 1, pos+1);
+    lua_rawseti(L, 1, pos);  /* t[pos] = t[pos+1] */
+  }
+  lua_pushnil(L);
+  lua_rawseti(L, 1, e);  /* t[e] = nil */
+  return 1;
+}
+
+
+static void addfield (lua_State *L, luaL_Buffer *b, int i) {
+  lua_rawgeti(L, 1, i);
+  if (!lua_isstring(L, -1))
+    luaL_error(L, "invalid value (%s) at index %d in table for "
+                  LUA_QL("concat"), luaL_typename(L, -1), i);
+    luaL_addvalue(b);
+}
+
+
+static int tconcat (lua_State *L) {
+  luaL_Buffer b;
+  size_t lsep;
+  int i, last;
+  const char *sep = luaL_optlstring(L, 2, "", &lsep);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i = luaL_optint(L, 3, 1);
+  last = luaL_opt(L, luaL_checkint, 4, luaL_getn(L, 1));
+  luaL_buffinit(L, &b);
+  for (; i < last; i++) {
+    addfield(L, &b, i);
+    luaL_addlstring(&b, sep, lsep);
+  }
+  if (i == last)  /* add last value (if interval was not empty) */
+    addfield(L, &b, i);
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+
+/*
+** {======================================================
+** Quicksort
+** (based on `Algorithms in MODULA-3', Robert Sedgewick;
+**  Addison-Wesley, 1993.)
+*/
+
+
+static void set2 (lua_State *L, int i, int j) {
+  lua_rawseti(L, 1, i);
+  lua_rawseti(L, 1, j);
+}
+
+static int sort_comp (lua_State *L, int a, int b) {
+  if (!lua_isnil(L, 2)) {  /* function? */
+    int res;
+    lua_pushvalue(L, 2);
+    lua_pushvalue(L, a-1);  /* -1 to compensate function */
+    lua_pushvalue(L, b-2);  /* -2 to compensate function and `a' */
+    lua_call(L, 2, 1);
+    res = lua_toboolean(L, -1);
+    lua_pop(L, 1);
+    return res;
+  }
+  else  /* a < b? */
+    return lua_lessthan(L, a, b);
+}
+
+static void auxsort (lua_State *L, int l, int u) {
+  while (l < u) {  /* for tail recursion */
+    int i, j;
+    /* sort elements a[l], a[(l+u)/2] and a[u] */
+    lua_rawgeti(L, 1, l);
+    lua_rawgeti(L, 1, u);
+    if (sort_comp(L, -1, -2))  /* a[u] < a[l]? */
+      set2(L, l, u);  /* swap a[l] - a[u] */
+    else
+      lua_pop(L, 2);
+    if (u-l == 1) break;  /* only 2 elements */
+    i = (l+u)/2;
+    lua_rawgeti(L, 1, i);
+    lua_rawgeti(L, 1, l);
+    if (sort_comp(L, -2, -1))  /* a[i]<a[l]? */
+      set2(L, i, l);
+    else {
+      lua_pop(L, 1);  /* remove a[l] */
+      lua_rawgeti(L, 1, u);
+      if (sort_comp(L, -1, -2))  /* a[u]<a[i]? */
+        set2(L, i, u);
+      else
+        lua_pop(L, 2);
+    }
+    if (u-l == 2) break;  /* only 3 elements */
+    lua_rawgeti(L, 1, i);  /* Pivot */
+    lua_pushvalue(L, -1);
+    lua_rawgeti(L, 1, u-1);
+    set2(L, i, u-1);
+    /* a[l] <= P == a[u-1] <= a[u], only need to sort from l+1 to u-2 */
+    i = l; j = u-1;
+    for (;;) {  /* invariant: a[l..i] <= P <= a[j..u] */
+      /* repeat ++i until a[i] >= P */
+      while (lua_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) {
+        if (i>u) luaL_error(L, "invalid order function for sorting");
+        lua_pop(L, 1);  /* remove a[i] */
+      }
+      /* repeat --j until a[j] <= P */
+      while (lua_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) {
+        if (j<l) luaL_error(L, "invalid order function for sorting");
+        lua_pop(L, 1);  /* remove a[j] */
+      }
+      if (j<i) {
+        lua_pop(L, 3);  /* pop pivot, a[i], a[j] */
+        break;
+      }
+      set2(L, i, j);
+    }
+    lua_rawgeti(L, 1, u-1);
+    lua_rawgeti(L, 1, i);
+    set2(L, u-1, i);  /* swap pivot (a[u-1]) with a[i] */
+    /* a[l..i-1] <= a[i] == P <= a[i+1..u] */
+    /* adjust so that smaller half is in [j..i] and larger one in [l..u] */
+    if (i-l < u-i) {
+      j=l; i=i-1; l=i+2;
+    }
+    else {
+      j=i+1; i=u; u=j-2;
+    }
+    auxsort(L, j, i);  /* call recursively the smaller one */
+  }  /* repeat the routine for the larger one */
+}
+
+static int sort (lua_State *L) {
+  int n = aux_getn(L, 1);
+  luaL_checkstack(L, 40, "");  /* assume array is smaller than 2^40 */
+  if (!lua_isnoneornil(L, 2))  /* is there a 2nd argument? */
+    luaL_checktype(L, 2, LUA_TFUNCTION);
+  lua_settop(L, 2);  /* make sure there is two arguments */
+  auxsort(L, 1, n);
+  return 0;
+}
+
+/* }====================================================== */
+
+
+static const luaL_Reg tab_funcs[] = {
+  {"concat", tconcat},
+  {"foreach", foreach},
+  {"foreachi", foreachi},
+  {"getn", getn},
+  {"maxn", maxn},
+  {"insert", tinsert},
+  {"remove", tremove},
+  {"setn", setn},
+  {"sort", sort},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_table (lua_State *L) {
+  luaL_register(L, LUA_TABLIBNAME, tab_funcs);
+  return 1;
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/ltm.c b/third_party/lua-src/lua-5.1.5/ltm.c
new file mode 100644
index 00000000..c27f0f6f
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ltm.c
@@ -0,0 +1,75 @@
+/*
+** $Id: ltm.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** Tag methods
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#define ltm_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+
+const char *const luaT_typenames[] = {
+  "nil", "boolean", "userdata", "number",
+  "string", "table", "function", "userdata", "thread",
+  "proto", "upval"
+};
+
+
+void luaT_init (lua_State *L) {
+  static const char *const luaT_eventname[] = {  /* ORDER TM */
+    "__index", "__newindex",
+    "__gc", "__mode", "__eq",
+    "__add", "__sub", "__mul", "__div", "__mod",
+    "__pow", "__unm", "__len", "__lt", "__le",
+    "__concat", "__call"
+  };
+  int i;
+  for (i=0; i<TM_N; i++) {
+    G(L)->tmname[i] = luaS_new(L, luaT_eventname[i]);
+    luaS_fix(G(L)->tmname[i]);  /* never collect these names */
+  }
+}
+
+
+/*
+** function to be used with macro "fasttm": optimized for absence of
+** tag methods
+*/
+const TValue *luaT_gettm (Table *events, TMS event, TString *ename) {
+  const TValue *tm = luaH_getstr(events, ename);
+  lua_assert(event <= TM_EQ);
+  if (ttisnil(tm)) {  /* no tag method? */
+    events->flags |= cast_byte(1u<<event);  /* cache this fact */
+    return NULL;
+  }
+  else return tm;
+}
+
+
+const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) {
+  Table *mt;
+  switch (ttype(o)) {
+    case LUA_TTABLE:
+      mt = hvalue(o)->metatable;
+      break;
+    case LUA_TUSERDATA:
+      mt = uvalue(o)->metatable;
+      break;
+    default:
+      mt = G(L)->mt[ttype(o)];
+  }
+  return (mt ? luaH_getstr(mt, G(L)->tmname[event]) : luaO_nilobject);
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/ltm.h b/third_party/lua-src/lua-5.1.5/ltm.h
new file mode 100644
index 00000000..64343b78
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/ltm.h
@@ -0,0 +1,54 @@
+/*
+** $Id: ltm.h,v 2.6.1.1 2007/12/27 13:02:25 roberto Exp $
+** Tag methods
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ltm_h
+#define ltm_h
+
+
+#include "lobject.h"
+
+
+/*
+* WARNING: if you change the order of this enumeration,
+* grep "ORDER TM"
+*/
+typedef enum {
+  TM_INDEX,
+  TM_NEWINDEX,
+  TM_GC,
+  TM_MODE,
+  TM_EQ,  /* last tag method with `fast' access */
+  TM_ADD,
+  TM_SUB,
+  TM_MUL,
+  TM_DIV,
+  TM_MOD,
+  TM_POW,
+  TM_UNM,
+  TM_LEN,
+  TM_LT,
+  TM_LE,
+  TM_CONCAT,
+  TM_CALL,
+  TM_N		/* number of elements in the enum */
+} TMS;
+
+
+
+#define gfasttm(g,et,e) ((et) == NULL ? NULL : \
+  ((et)->flags & (1u<<(e))) ? NULL : luaT_gettm(et, e, (g)->tmname[e]))
+
+#define fasttm(l,et,e)	gfasttm(G(l), et, e)
+
+LUAI_DATA const char *const luaT_typenames[];
+
+
+LUAI_FUNC const TValue *luaT_gettm (Table *events, TMS event, TString *ename);
+LUAI_FUNC const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o,
+                                                       TMS event);
+LUAI_FUNC void luaT_init (lua_State *L);
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lua.h b/third_party/lua-src/lua-5.1.5/lua.h
new file mode 100644
index 00000000..a4b73e74
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lua.h
@@ -0,0 +1,388 @@
+/*
+** $Id: lua.h,v 1.218.1.7 2012/01/13 20:36:20 roberto Exp $
+** Lua - An Extensible Extension Language
+** Lua.org, PUC-Rio, Brazil (http://www.lua.org)
+** See Copyright Notice at the end of this file
+*/
+
+
+#ifndef lua_h
+#define lua_h
+
+#include <stdarg.h>
+#include <stddef.h>
+
+
+#include "luaconf.h"
+
+
+#define LUA_VERSION	"Lua 5.1"
+#define LUA_RELEASE	"Lua 5.1.5"
+#define LUA_VERSION_NUM	501
+#define LUA_COPYRIGHT	"Copyright (C) 1994-2012 Lua.org, PUC-Rio"
+#define LUA_AUTHORS 	"R. Ierusalimschy, L. H. de Figueiredo & W. Celes"
+
+
+/* mark for precompiled code (`<esc>Lua') */
+#define	LUA_SIGNATURE	"\033Lua"
+
+/* option for multiple returns in `lua_pcall' and `lua_call' */
+#define LUA_MULTRET	(-1)
+
+
+/*
+** pseudo-indices
+*/
+#define LUA_REGISTRYINDEX	(-10000)
+#define LUA_ENVIRONINDEX	(-10001)
+#define LUA_GLOBALSINDEX	(-10002)
+#define lua_upvalueindex(i)	(LUA_GLOBALSINDEX-(i))
+
+
+/* thread status; 0 is OK */
+#define LUA_YIELD	1
+#define LUA_ERRRUN	2
+#define LUA_ERRSYNTAX	3
+#define LUA_ERRMEM	4
+#define LUA_ERRERR	5
+
+
+typedef struct lua_State lua_State;
+
+typedef int (*lua_CFunction) (lua_State *L);
+
+
+/*
+** functions that read/write blocks when loading/dumping Lua chunks
+*/
+typedef const char * (*lua_Reader) (lua_State *L, void *ud, size_t *sz);
+
+typedef int (*lua_Writer) (lua_State *L, const void* p, size_t sz, void* ud);
+
+
+/*
+** prototype for memory-allocation functions
+*/
+typedef void * (*lua_Alloc) (void *ud, void *ptr, size_t osize, size_t nsize);
+
+
+/*
+** basic types
+*/
+#define LUA_TNONE		(-1)
+
+#define LUA_TNIL		0
+#define LUA_TBOOLEAN		1
+#define LUA_TLIGHTUSERDATA	2
+#define LUA_TNUMBER		3
+#define LUA_TSTRING		4
+#define LUA_TTABLE		5
+#define LUA_TFUNCTION		6
+#define LUA_TUSERDATA		7
+#define LUA_TTHREAD		8
+
+
+
+/* minimum Lua stack available to a C function */
+#define LUA_MINSTACK	20
+
+
+/*
+** generic extra include file
+*/
+#if defined(LUA_USER_H)
+#include LUA_USER_H
+#endif
+
+
+/* type of numbers in Lua */
+typedef LUA_NUMBER lua_Number;
+
+
+/* type for integer functions */
+typedef LUA_INTEGER lua_Integer;
+
+
+
+/*
+** state manipulation
+*/
+LUA_API lua_State *(lua_newstate) (lua_Alloc f, void *ud);
+LUA_API void       (lua_close) (lua_State *L);
+LUA_API lua_State *(lua_newthread) (lua_State *L);
+
+LUA_API lua_CFunction (lua_atpanic) (lua_State *L, lua_CFunction panicf);
+
+
+/*
+** basic stack manipulation
+*/
+LUA_API int   (lua_gettop) (lua_State *L);
+LUA_API void  (lua_settop) (lua_State *L, int idx);
+LUA_API void  (lua_pushvalue) (lua_State *L, int idx);
+LUA_API void  (lua_remove) (lua_State *L, int idx);
+LUA_API void  (lua_insert) (lua_State *L, int idx);
+LUA_API void  (lua_replace) (lua_State *L, int idx);
+LUA_API int   (lua_checkstack) (lua_State *L, int sz);
+
+LUA_API void  (lua_xmove) (lua_State *from, lua_State *to, int n);
+
+
+/*
+** access functions (stack -> C)
+*/
+
+LUA_API int             (lua_isnumber) (lua_State *L, int idx);
+LUA_API int             (lua_isstring) (lua_State *L, int idx);
+LUA_API int             (lua_iscfunction) (lua_State *L, int idx);
+LUA_API int             (lua_isuserdata) (lua_State *L, int idx);
+LUA_API int             (lua_type) (lua_State *L, int idx);
+LUA_API const char     *(lua_typename) (lua_State *L, int tp);
+
+LUA_API int            (lua_equal) (lua_State *L, int idx1, int idx2);
+LUA_API int            (lua_rawequal) (lua_State *L, int idx1, int idx2);
+LUA_API int            (lua_lessthan) (lua_State *L, int idx1, int idx2);
+
+LUA_API lua_Number      (lua_tonumber) (lua_State *L, int idx);
+LUA_API lua_Integer     (lua_tointeger) (lua_State *L, int idx);
+LUA_API int             (lua_toboolean) (lua_State *L, int idx);
+LUA_API const char     *(lua_tolstring) (lua_State *L, int idx, size_t *len);
+LUA_API size_t          (lua_objlen) (lua_State *L, int idx);
+LUA_API lua_CFunction   (lua_tocfunction) (lua_State *L, int idx);
+LUA_API void	       *(lua_touserdata) (lua_State *L, int idx);
+LUA_API lua_State      *(lua_tothread) (lua_State *L, int idx);
+LUA_API const void     *(lua_topointer) (lua_State *L, int idx);
+
+
+/*
+** push functions (C -> stack)
+*/
+LUA_API void  (lua_pushnil) (lua_State *L);
+LUA_API void  (lua_pushnumber) (lua_State *L, lua_Number n);
+LUA_API void  (lua_pushinteger) (lua_State *L, lua_Integer n);
+LUA_API void  (lua_pushlstring) (lua_State *L, const char *s, size_t l);
+LUA_API void  (lua_pushstring) (lua_State *L, const char *s);
+LUA_API const char *(lua_pushvfstring) (lua_State *L, const char *fmt,
+                                                      va_list argp);
+LUA_API const char *(lua_pushfstring) (lua_State *L, const char *fmt, ...);
+LUA_API void  (lua_pushcclosure) (lua_State *L, lua_CFunction fn, int n);
+LUA_API void  (lua_pushboolean) (lua_State *L, int b);
+LUA_API void  (lua_pushlightuserdata) (lua_State *L, void *p);
+LUA_API int   (lua_pushthread) (lua_State *L);
+
+
+/*
+** get functions (Lua -> stack)
+*/
+LUA_API void  (lua_gettable) (lua_State *L, int idx);
+LUA_API void  (lua_getfield) (lua_State *L, int idx, const char *k);
+LUA_API void  (lua_rawget) (lua_State *L, int idx);
+LUA_API void  (lua_rawgeti) (lua_State *L, int idx, int n);
+LUA_API void  (lua_createtable) (lua_State *L, int narr, int nrec);
+LUA_API void *(lua_newuserdata) (lua_State *L, size_t sz);
+LUA_API int   (lua_getmetatable) (lua_State *L, int objindex);
+LUA_API void  (lua_getfenv) (lua_State *L, int idx);
+
+
+/*
+** set functions (stack -> Lua)
+*/
+LUA_API void  (lua_settable) (lua_State *L, int idx);
+LUA_API void  (lua_setfield) (lua_State *L, int idx, const char *k);
+LUA_API void  (lua_rawset) (lua_State *L, int idx);
+LUA_API void  (lua_rawseti) (lua_State *L, int idx, int n);
+LUA_API int   (lua_setmetatable) (lua_State *L, int objindex);
+LUA_API int   (lua_setfenv) (lua_State *L, int idx);
+
+
+/*
+** `load' and `call' functions (load and run Lua code)
+*/
+LUA_API void  (lua_call) (lua_State *L, int nargs, int nresults);
+LUA_API int   (lua_pcall) (lua_State *L, int nargs, int nresults, int errfunc);
+LUA_API int   (lua_cpcall) (lua_State *L, lua_CFunction func, void *ud);
+LUA_API int   (lua_load) (lua_State *L, lua_Reader reader, void *dt,
+                                        const char *chunkname);
+
+LUA_API int (lua_dump) (lua_State *L, lua_Writer writer, void *data);
+
+
+/*
+** coroutine functions
+*/
+LUA_API int  (lua_yield) (lua_State *L, int nresults);
+LUA_API int  (lua_resume) (lua_State *L, int narg);
+LUA_API int  (lua_status) (lua_State *L);
+
+/*
+** garbage-collection function and options
+*/
+
+#define LUA_GCSTOP		0
+#define LUA_GCRESTART		1
+#define LUA_GCCOLLECT		2
+#define LUA_GCCOUNT		3
+#define LUA_GCCOUNTB		4
+#define LUA_GCSTEP		5
+#define LUA_GCSETPAUSE		6
+#define LUA_GCSETSTEPMUL	7
+
+LUA_API int (lua_gc) (lua_State *L, int what, int data);
+
+
+/*
+** miscellaneous functions
+*/
+
+LUA_API int   (lua_error) (lua_State *L);
+
+LUA_API int   (lua_next) (lua_State *L, int idx);
+
+LUA_API void  (lua_concat) (lua_State *L, int n);
+
+LUA_API lua_Alloc (lua_getallocf) (lua_State *L, void **ud);
+LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud);
+
+
+
+/* 
+** ===============================================================
+** some useful macros
+** ===============================================================
+*/
+
+#define lua_pop(L,n)		lua_settop(L, -(n)-1)
+
+#define lua_newtable(L)		lua_createtable(L, 0, 0)
+
+#define lua_register(L,n,f) (lua_pushcfunction(L, (f)), lua_setglobal(L, (n)))
+
+#define lua_pushcfunction(L,f)	lua_pushcclosure(L, (f), 0)
+
+#define lua_strlen(L,i)		lua_objlen(L, (i))
+
+#define lua_isfunction(L,n)	(lua_type(L, (n)) == LUA_TFUNCTION)
+#define lua_istable(L,n)	(lua_type(L, (n)) == LUA_TTABLE)
+#define lua_islightuserdata(L,n)	(lua_type(L, (n)) == LUA_TLIGHTUSERDATA)
+#define lua_isnil(L,n)		(lua_type(L, (n)) == LUA_TNIL)
+#define lua_isboolean(L,n)	(lua_type(L, (n)) == LUA_TBOOLEAN)
+#define lua_isthread(L,n)	(lua_type(L, (n)) == LUA_TTHREAD)
+#define lua_isnone(L,n)		(lua_type(L, (n)) == LUA_TNONE)
+#define lua_isnoneornil(L, n)	(lua_type(L, (n)) <= 0)
+
+#define lua_pushliteral(L, s)	\
+	lua_pushlstring(L, "" s, (sizeof(s)/sizeof(char))-1)
+
+#define lua_setglobal(L,s)	lua_setfield(L, LUA_GLOBALSINDEX, (s))
+#define lua_getglobal(L,s)	lua_getfield(L, LUA_GLOBALSINDEX, (s))
+
+#define lua_tostring(L,i)	lua_tolstring(L, (i), NULL)
+
+
+
+/*
+** compatibility macros and functions
+*/
+
+#define lua_open()	luaL_newstate()
+
+#define lua_getregistry(L)	lua_pushvalue(L, LUA_REGISTRYINDEX)
+
+#define lua_getgccount(L)	lua_gc(L, LUA_GCCOUNT, 0)
+
+#define lua_Chunkreader		lua_Reader
+#define lua_Chunkwriter		lua_Writer
+
+
+/* hack */
+LUA_API void lua_setlevel	(lua_State *from, lua_State *to);
+
+
+/*
+** {======================================================================
+** Debug API
+** =======================================================================
+*/
+
+
+/*
+** Event codes
+*/
+#define LUA_HOOKCALL	0
+#define LUA_HOOKRET	1
+#define LUA_HOOKLINE	2
+#define LUA_HOOKCOUNT	3
+#define LUA_HOOKTAILRET 4
+
+
+/*
+** Event masks
+*/
+#define LUA_MASKCALL	(1 << LUA_HOOKCALL)
+#define LUA_MASKRET	(1 << LUA_HOOKRET)
+#define LUA_MASKLINE	(1 << LUA_HOOKLINE)
+#define LUA_MASKCOUNT	(1 << LUA_HOOKCOUNT)
+
+typedef struct lua_Debug lua_Debug;  /* activation record */
+
+
+/* Functions to be called by the debuger in specific events */
+typedef void (*lua_Hook) (lua_State *L, lua_Debug *ar);
+
+
+LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar);
+LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar);
+LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n);
+LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n);
+LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n);
+LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n);
+
+LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count);
+LUA_API lua_Hook lua_gethook (lua_State *L);
+LUA_API int lua_gethookmask (lua_State *L);
+LUA_API int lua_gethookcount (lua_State *L);
+
+
+struct lua_Debug {
+  int event;
+  const char *name;	/* (n) */
+  const char *namewhat;	/* (n) `global', `local', `field', `method' */
+  const char *what;	/* (S) `Lua', `C', `main', `tail' */
+  const char *source;	/* (S) */
+  int currentline;	/* (l) */
+  int nups;		/* (u) number of upvalues */
+  int linedefined;	/* (S) */
+  int lastlinedefined;	/* (S) */
+  char short_src[LUA_IDSIZE]; /* (S) */
+  /* private part */
+  int i_ci;  /* active function */
+};
+
+/* }====================================================================== */
+
+
+/******************************************************************************
+* Copyright (C) 1994-2012 Lua.org, PUC-Rio.  All rights reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+******************************************************************************/
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/luaconf.h b/third_party/lua-src/lua-5.1.5/luaconf.h
new file mode 100644
index 00000000..457ad041
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/luaconf.h
@@ -0,0 +1,770 @@
+/*
+** $Id: luaconf.h,v 1.82.1.7 2008/02/11 16:25:08 roberto Exp $
+** Configuration file for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lconfig_h
+#define lconfig_h
+
+#include <limits.h>
+#include <stddef.h>
+
+
+/*
+** ==================================================================
+** Search for "@@" to find all configurable definitions.
+** ===================================================================
+*/
+
+
+/*
+@@ LUA_ANSI controls the use of non-ansi features.
+** CHANGE it (define it) if you want Lua to avoid the use of any
+** non-ansi feature or library.
+*/
+#if defined(__STRICT_ANSI__)
+#define LUA_ANSI
+#endif
+
+
+#if !defined(LUA_ANSI) && defined(_WIN32)
+#define LUA_WIN
+#endif
+
+#if defined(LUA_USE_LINUX)
+#define LUA_USE_POSIX
+#define LUA_USE_DLOPEN		/* needs an extra library: -ldl */
+#define LUA_USE_READLINE	/* needs some extra libraries */
+#endif
+
+#if defined(LUA_USE_MACOSX)
+#define LUA_USE_POSIX
+#define LUA_DL_DYLD		/* does not need extra library */
+#endif
+
+
+
+/*
+@@ LUA_USE_POSIX includes all functionallity listed as X/Open System
+@* Interfaces Extension (XSI).
+** CHANGE it (define it) if your system is XSI compatible.
+*/
+#if defined(LUA_USE_POSIX)
+#define LUA_USE_MKSTEMP
+#define LUA_USE_ISATTY
+#if !defined(__wasi__)
+#define LUA_USE_POPEN
+#endif
+#define LUA_USE_ULONGJMP
+#endif
+
+
+/*
+@@ LUA_PATH and LUA_CPATH are the names of the environment variables that
+@* Lua check to set its paths.
+@@ LUA_INIT is the name of the environment variable that Lua
+@* checks for initialization code.
+** CHANGE them if you want different names.
+*/
+#define LUA_PATH        "LUA_PATH"
+#define LUA_CPATH       "LUA_CPATH"
+#define LUA_INIT	"LUA_INIT"
+
+
+/*
+@@ LUA_PATH_DEFAULT is the default path that Lua uses to look for
+@* Lua libraries.
+@@ LUA_CPATH_DEFAULT is the default path that Lua uses to look for
+@* C libraries.
+** CHANGE them if your machine has a non-conventional directory
+** hierarchy or if you want to install your libraries in
+** non-conventional directories.
+*/
+#if defined(_WIN32)
+/*
+** In Windows, any exclamation mark ('!') in the path is replaced by the
+** path of the directory of the executable file of the current process.
+*/
+#define LUA_LDIR	"!\\lua\\"
+#define LUA_CDIR	"!\\"
+#define LUA_PATH_DEFAULT  \
+		".\\?.lua;"  LUA_LDIR"?.lua;"  LUA_LDIR"?\\init.lua;" \
+		             LUA_CDIR"?.lua;"  LUA_CDIR"?\\init.lua"
+#define LUA_CPATH_DEFAULT \
+	".\\?.dll;"  LUA_CDIR"?.dll;" LUA_CDIR"loadall.dll"
+
+#else
+#define LUA_ROOT	"/usr/local/"
+#define LUA_LDIR	LUA_ROOT "share/lua/5.1/"
+#define LUA_CDIR	LUA_ROOT "lib/lua/5.1/"
+#define LUA_PATH_DEFAULT  \
+		"./?.lua;"  LUA_LDIR"?.lua;"  LUA_LDIR"?/init.lua;" \
+		            LUA_CDIR"?.lua;"  LUA_CDIR"?/init.lua"
+#define LUA_CPATH_DEFAULT \
+	"./?.so;"  LUA_CDIR"?.so;" LUA_CDIR"loadall.so"
+#endif
+
+
+/*
+@@ LUA_DIRSEP is the directory separator (for submodules).
+** CHANGE it if your machine does not use "/" as the directory separator
+** and is not Windows. (On Windows Lua automatically uses "\".)
+*/
+#if defined(_WIN32)
+#define LUA_DIRSEP	"\\"
+#else
+#define LUA_DIRSEP	"/"
+#endif
+
+
+/*
+@@ LUA_PATHSEP is the character that separates templates in a path.
+@@ LUA_PATH_MARK is the string that marks the substitution points in a
+@* template.
+@@ LUA_EXECDIR in a Windows path is replaced by the executable's
+@* directory.
+@@ LUA_IGMARK is a mark to ignore all before it when bulding the
+@* luaopen_ function name.
+** CHANGE them if for some reason your system cannot use those
+** characters. (E.g., if one of those characters is a common character
+** in file/directory names.) Probably you do not need to change them.
+*/
+#define LUA_PATHSEP	";"
+#define LUA_PATH_MARK	"?"
+#define LUA_EXECDIR	"!"
+#define LUA_IGMARK	"-"
+
+
+/*
+@@ LUA_INTEGER is the integral type used by lua_pushinteger/lua_tointeger.
+** CHANGE that if ptrdiff_t is not adequate on your machine. (On most
+** machines, ptrdiff_t gives a good choice between int or long.)
+*/
+#define LUA_INTEGER	ptrdiff_t
+
+
+/*
+@@ LUA_API is a mark for all core API functions.
+@@ LUALIB_API is a mark for all standard library functions.
+** CHANGE them if you need to define those functions in some special way.
+** For instance, if you want to create one Windows DLL with the core and
+** the libraries, you may want to use the following definition (define
+** LUA_BUILD_AS_DLL to get it).
+*/
+#if defined(LUA_BUILD_AS_DLL)
+
+#if defined(LUA_CORE) || defined(LUA_LIB)
+#define LUA_API __declspec(dllexport)
+#else
+#define LUA_API __declspec(dllimport)
+#endif
+
+#else
+
+#define LUA_API		extern
+
+#endif
+
+/* more often than not the libs go together with the core */
+#define LUALIB_API	LUA_API
+
+
+/*
+@@ LUAI_FUNC is a mark for all extern functions that are not to be
+@* exported to outside modules.
+@@ LUAI_DATA is a mark for all extern (const) variables that are not to
+@* be exported to outside modules.
+** CHANGE them if you need to mark them in some special way. Elf/gcc
+** (versions 3.2 and later) mark them as "hidden" to optimize access
+** when Lua is compiled as a shared library.
+*/
+#if defined(luaall_c)
+#define LUAI_FUNC	static
+#define LUAI_DATA	/* empty */
+
+#elif defined(__GNUC__) && ((__GNUC__*100 + __GNUC_MINOR__) >= 302) && \
+      defined(__ELF__)
+#define LUAI_FUNC	__attribute__((visibility("hidden"))) extern
+#define LUAI_DATA	LUAI_FUNC
+
+#else
+#define LUAI_FUNC	extern
+#define LUAI_DATA	extern
+#endif
+
+
+
+/*
+@@ LUA_QL describes how error messages quote program elements.
+** CHANGE it if you want a different appearance.
+*/
+#define LUA_QL(x)	"'" x "'"
+#define LUA_QS		LUA_QL("%s")
+
+
+/*
+@@ LUA_IDSIZE gives the maximum size for the description of the source
+@* of a function in debug information.
+** CHANGE it if you want a different size.
+*/
+#define LUA_IDSIZE	60
+
+
+/*
+** {==================================================================
+** Stand-alone configuration
+** ===================================================================
+*/
+
+#if defined(lua_c) || defined(luaall_c)
+
+/*
+@@ lua_stdin_is_tty detects whether the standard input is a 'tty' (that
+@* is, whether we're running lua interactively).
+** CHANGE it if you have a better definition for non-POSIX/non-Windows
+** systems.
+*/
+#if defined(LUA_USE_ISATTY)
+#include <unistd.h>
+#define lua_stdin_is_tty()	isatty(0)
+#elif defined(LUA_WIN)
+#include <io.h>
+#include <stdio.h>
+#define lua_stdin_is_tty()	_isatty(_fileno(stdin))
+#else
+#define lua_stdin_is_tty()	1  /* assume stdin is a tty */
+#endif
+
+
+/*
+@@ LUA_PROMPT is the default prompt used by stand-alone Lua.
+@@ LUA_PROMPT2 is the default continuation prompt used by stand-alone Lua.
+** CHANGE them if you want different prompts. (You can also change the
+** prompts dynamically, assigning to globals _PROMPT/_PROMPT2.)
+*/
+#define LUA_PROMPT		"> "
+#define LUA_PROMPT2		">> "
+
+
+/*
+@@ LUA_PROGNAME is the default name for the stand-alone Lua program.
+** CHANGE it if your stand-alone interpreter has a different name and
+** your system is not able to detect that name automatically.
+*/
+#define LUA_PROGNAME		"lua"
+
+
+/*
+@@ LUA_MAXINPUT is the maximum length for an input line in the
+@* stand-alone interpreter.
+** CHANGE it if you need longer lines.
+*/
+#define LUA_MAXINPUT	512
+
+
+/*
+@@ lua_readline defines how to show a prompt and then read a line from
+@* the standard input.
+@@ lua_saveline defines how to "save" a read line in a "history".
+@@ lua_freeline defines how to free a line read by lua_readline.
+** CHANGE them if you want to improve this functionality (e.g., by using
+** GNU readline and history facilities).
+*/
+#if defined(LUA_USE_READLINE)
+#include <stdio.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+#define lua_readline(L,b,p)	((void)L, ((b)=readline(p)) != NULL)
+#define lua_saveline(L,idx) \
+	if (lua_strlen(L,idx) > 0)  /* non-empty line? */ \
+	  add_history(lua_tostring(L, idx));  /* add it to history */
+#define lua_freeline(L,b)	((void)L, free(b))
+#else
+#define lua_readline(L,b,p)	\
+	((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
+	fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
+#define lua_saveline(L,idx)	{ (void)L; (void)idx; }
+#define lua_freeline(L,b)	{ (void)L; (void)b; }
+#endif
+
+#endif
+
+/* }================================================================== */
+
+
+/*
+@@ LUAI_GCPAUSE defines the default pause between garbage-collector cycles
+@* as a percentage.
+** CHANGE it if you want the GC to run faster or slower (higher values
+** mean larger pauses which mean slower collection.) You can also change
+** this value dynamically.
+*/
+#define LUAI_GCPAUSE	200  /* 200% (wait memory to double before next GC) */
+
+
+/*
+@@ LUAI_GCMUL defines the default speed of garbage collection relative to
+@* memory allocation as a percentage.
+** CHANGE it if you want to change the granularity of the garbage
+** collection. (Higher values mean coarser collections. 0 represents
+** infinity, where each step performs a full collection.) You can also
+** change this value dynamically.
+*/
+#define LUAI_GCMUL	200 /* GC runs 'twice the speed' of memory allocation */
+
+
+
+/*
+@@ LUA_COMPAT_GETN controls compatibility with old getn behavior.
+** CHANGE it (define it) if you want exact compatibility with the
+** behavior of setn/getn in Lua 5.0.
+*/
+#undef LUA_COMPAT_GETN
+
+/*
+@@ LUA_COMPAT_LOADLIB controls compatibility about global loadlib.
+** CHANGE it to undefined as soon as you do not need a global 'loadlib'
+** function (the function is still available as 'package.loadlib').
+*/
+#undef LUA_COMPAT_LOADLIB
+
+/*
+@@ LUA_COMPAT_VARARG controls compatibility with old vararg feature.
+** CHANGE it to undefined as soon as your programs use only '...' to
+** access vararg parameters (instead of the old 'arg' table).
+*/
+#define LUA_COMPAT_VARARG
+
+/*
+@@ LUA_COMPAT_MOD controls compatibility with old math.mod function.
+** CHANGE it to undefined as soon as your programs use 'math.fmod' or
+** the new '%' operator instead of 'math.mod'.
+*/
+#define LUA_COMPAT_MOD
+
+/*
+@@ LUA_COMPAT_LSTR controls compatibility with old long string nesting
+@* facility.
+** CHANGE it to 2 if you want the old behaviour, or undefine it to turn
+** off the advisory error when nesting [[...]].
+*/
+/* BENILLA: 2, the 5.0 behaviour. 1.12.1 ships Lua 5.0, where `[[ ... [[ ... ]] ... ]]`
+** nests; 5.1 kept the machinery and put an advisory error in front of it. Two corpus
+** addons stop loading on "nesting of [[...]] is deprecated" — a 5.1 opinion about a
+** dialect we are not targeting. Same family as the OP_TFORPREP restoration (1215).
+*/
+#define LUA_COMPAT_LSTR		2
+
+/*
+@@ LUA_COMPAT_GFIND controls compatibility with old 'string.gfind' name.
+** CHANGE it to undefined as soon as you rename 'string.gfind' to
+** 'string.gmatch'.
+*/
+#define LUA_COMPAT_GFIND
+
+/*
+@@ LUA_COMPAT_OPENLIB controls compatibility with old 'luaL_openlib'
+@* behavior.
+** CHANGE it to undefined as soon as you replace to 'luaL_register'
+** your uses of 'luaL_openlib'
+*/
+#define LUA_COMPAT_OPENLIB
+
+
+
+/*
+@@ luai_apicheck is the assert macro used by the Lua-C API.
+** CHANGE luai_apicheck if you want Lua to perform some checks in the
+** parameters it gets from API calls. This may slow down the interpreter
+** a bit, but may be quite useful when debugging C code that interfaces
+** with Lua. A useful redefinition is to use assert.h.
+*/
+#if defined(LUA_USE_APICHECK)
+#include <assert.h>
+#define luai_apicheck(L,o)	{ (void)L; assert(o); }
+#else
+#define luai_apicheck(L,o)	{ (void)L; }
+#endif
+
+
+/*
+@@ LUAI_BITSINT defines the number of bits in an int.
+** CHANGE here if Lua cannot automatically detect the number of bits of
+** your machine. Probably you do not need to change this.
+*/
+/* avoid overflows in comparison */
+#if INT_MAX-20 < 32760
+#define LUAI_BITSINT	16
+#elif INT_MAX > 2147483640L
+/* int has at least 32 bits */
+#define LUAI_BITSINT	32
+#else
+#error "you must define LUA_BITSINT with number of bits in an integer"
+#endif
+
+
+/*
+@@ LUAI_UINT32 is an unsigned integer with at least 32 bits.
+@@ LUAI_INT32 is an signed integer with at least 32 bits.
+@@ LUAI_UMEM is an unsigned integer big enough to count the total
+@* memory used by Lua.
+@@ LUAI_MEM is a signed integer big enough to count the total memory
+@* used by Lua.
+** CHANGE here if for some weird reason the default definitions are not
+** good enough for your machine. (The definitions in the 'else'
+** part always works, but may waste space on machines with 64-bit
+** longs.) Probably you do not need to change this.
+*/
+#if LUAI_BITSINT >= 32
+#define LUAI_UINT32	unsigned int
+#define LUAI_INT32	int
+#define LUAI_MAXINT32	INT_MAX
+#define LUAI_UMEM	size_t
+#define LUAI_MEM	ptrdiff_t
+#else
+/* 16-bit ints */
+#define LUAI_UINT32	unsigned long
+#define LUAI_INT32	long
+#define LUAI_MAXINT32	LONG_MAX
+#define LUAI_UMEM	unsigned long
+#define LUAI_MEM	long
+#endif
+
+
+/*
+@@ LUAI_MAXCALLS limits the number of nested calls.
+** CHANGE it if you need really deep recursive calls. This limit is
+** arbitrary; its only purpose is to stop infinite recursion before
+** exhausting memory.
+*/
+#define LUAI_MAXCALLS	20000
+
+
+/*
+@@ LUAI_MAXCSTACK limits the number of Lua stack slots that a C function
+@* can use.
+** CHANGE it if you need lots of (Lua) stack space for your C
+** functions. This limit is arbitrary; its only purpose is to stop C
+** functions to consume unlimited stack space. (must be smaller than
+** -LUA_REGISTRYINDEX)
+*/
+#define LUAI_MAXCSTACK	8000
+
+
+
+/*
+** {==================================================================
+** CHANGE (to smaller values) the following definitions if your system
+** has a small C stack. (Or you may want to change them to larger
+** values if your system has a large C stack and these limits are
+** too rigid for you.) Some of these constants control the size of
+** stack-allocated arrays used by the compiler or the interpreter, while
+** others limit the maximum number of recursive calls that the compiler
+** or the interpreter can perform. Values too large may cause a C stack
+** overflow for some forms of deep constructs.
+** ===================================================================
+*/
+
+
+/*
+@@ LUAI_MAXCCALLS is the maximum depth for nested C calls (short) and
+@* syntactical nested non-terminals in a program.
+*/
+#define LUAI_MAXCCALLS		200
+
+
+/*
+@@ LUAI_MAXVARS is the maximum number of local variables per function
+@* (must be smaller than 250).
+*/
+#define LUAI_MAXVARS		200
+
+
+/*
+@@ LUAI_MAXUPVALUES is the maximum number of upvalues per function
+@* (must be smaller than 250).
+*/
+#define LUAI_MAXUPVALUES	60
+
+
+/*
+@@ LUAL_BUFFERSIZE is the buffer size used by the lauxlib buffer system.
+*/
+#define LUAL_BUFFERSIZE		BUFSIZ
+
+/* }================================================================== */
+
+
+
+
+/*
+** {==================================================================
+@@ LUA_NUMBER is the type of numbers in Lua.
+** CHANGE the following definitions only if you want to build Lua
+** with a number type different from double. You may also need to
+** change lua_number2int & lua_number2integer.
+** ===================================================================
+*/
+
+#define LUA_NUMBER_DOUBLE
+#define LUA_NUMBER	double
+
+/*
+@@ LUAI_UACNUMBER is the result of an 'usual argument conversion'
+@* over a number.
+*/
+#define LUAI_UACNUMBER	double
+
+
+/*
+@@ LUA_NUMBER_SCAN is the format for reading numbers.
+@@ LUA_NUMBER_FMT is the format for writing numbers.
+@@ lua_number2str converts a number to a string.
+@@ LUAI_MAXNUMBER2STR is maximum size of previous conversion.
+@@ lua_str2number converts a string to a number.
+*/
+#define LUA_NUMBER_SCAN		"%lf"
+#define LUA_NUMBER_FMT		"%.14g"
+#define lua_number2str(s,n)	sprintf((s), LUA_NUMBER_FMT, (n))
+#define LUAI_MAXNUMBER2STR	32 /* 16 digits, sign, point, and \0 */
+#define lua_str2number(s,p)	strtod((s), (p))
+
+
+/*
+@@ The luai_num* macros define the primitive operations over numbers.
+*/
+#if defined(LUA_CORE)
+#include <math.h>
+#define luai_numadd(a,b)	((a)+(b))
+#define luai_numsub(a,b)	((a)-(b))
+#define luai_nummul(a,b)	((a)*(b))
+#define luai_numdiv(a,b)	((a)/(b))
+#define luai_nummod(a,b)	((a) - floor((a)/(b))*(b))
+#define luai_numpow(a,b)	(pow(a,b))
+#define luai_numunm(a)		(-(a))
+#define luai_numeq(a,b)		((a)==(b))
+#define luai_numlt(a,b)		((a)<(b))
+#define luai_numle(a,b)		((a)<=(b))
+#define luai_numisnan(a)	(!luai_numeq((a), (a)))
+#endif
+
+
+/*
+@@ lua_number2int is a macro to convert lua_Number to int.
+@@ lua_number2integer is a macro to convert lua_Number to lua_Integer.
+** CHANGE them if you know a faster way to convert a lua_Number to
+** int (with any rounding method and without throwing errors) in your
+** system. In Pentium machines, a naive typecast from double to int
+** in C is extremely slow, so any alternative is worth trying.
+*/
+
+/* On a Pentium, resort to a trick */
+#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI) && !defined(__SSE2__) && \
+    (defined(__i386) || defined (_M_IX86) || defined(__i386__))
+
+/* On a Microsoft compiler, use assembler */
+#if defined(_MSC_VER)
+
+#define lua_number2int(i,d)   __asm fld d   __asm fistp i
+#define lua_number2integer(i,n)		lua_number2int(i, n)
+
+/* the next trick should work on any Pentium, but sometimes clashes
+   with a DirectX idiosyncrasy */
+#else
+
+union luai_Cast { double l_d; long l_l; };
+#define lua_number2int(i,d) \
+  { volatile union luai_Cast u; u.l_d = (d) + 6755399441055744.0; (i) = u.l_l; }
+#define lua_number2integer(i,n)		lua_number2int(i, n)
+
+#endif
+
+
+/* this option always works, but may be slow */
+#else
+#define lua_number2int(i,d)	((i)=(int)(d))
+#define lua_number2integer(i,d)	((i)=(lua_Integer)(d))
+
+#endif
+
+/* }================================================================== */
+
+
+/*
+@@ LUAI_USER_ALIGNMENT_T is a type that requires maximum alignment.
+** CHANGE it if your system requires alignments larger than double. (For
+** instance, if your system supports long doubles and they must be
+** aligned in 16-byte boundaries, then you should add long double in the
+** union.) Probably you do not need to change this.
+*/
+#define LUAI_USER_ALIGNMENT_T	union { double u; void *s; long l; }
+
+
+/*
+@@ LUAI_THROW/LUAI_TRY define how Lua does exception handling.
+** CHANGE them if you prefer to use longjmp/setjmp even with C++
+** or if want/don't to use _longjmp/_setjmp instead of regular
+** longjmp/setjmp. By default, Lua handles errors with exceptions when
+** compiling as C++ code, with _longjmp/_setjmp when asked to use them,
+** and with longjmp/setjmp otherwise.
+*/
+#if defined(__cplusplus)
+/* C++ exceptions */
+#define LUAI_THROW(L,c)	throw(c)
+#define LUAI_TRY(L,c,a)	try { a } catch(...) \
+	{ if ((c)->status == 0) (c)->status = -1; }
+#define luai_jmpbuf	int  /* dummy variable */
+
+#elif defined(LUA_USE_ULONGJMP)
+/* in Unix, try _longjmp/_setjmp (more efficient) */
+#define LUAI_THROW(L,c)	_longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)	if (_setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf	jmp_buf
+
+#else
+/* default handling with long jumps */
+#define LUAI_THROW(L,c)	longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)	if (setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf	jmp_buf
+
+#endif
+
+
+/*
+@@ LUA_MAXCAPTURES is the maximum number of captures that a pattern
+@* can do during pattern-matching.
+** CHANGE it if you need more captures. This limit is arbitrary.
+*/
+#define LUA_MAXCAPTURES		32
+
+
+/*
+@@ lua_tmpnam is the function that the OS library uses to create a
+@* temporary name.
+@@ LUA_TMPNAMBUFSIZE is the maximum size of a name created by lua_tmpnam.
+** CHANGE them if you have an alternative to tmpnam (which is considered
+** insecure) or if you want the original tmpnam anyway.  By default, Lua
+** uses tmpnam except when POSIX is available, where it uses mkstemp.
+*/
+#if defined(loslib_c) || defined(luaall_c)
+
+#if defined(LUA_USE_MKSTEMP)
+#include <unistd.h>
+#define LUA_TMPNAMBUFSIZE	32
+#define lua_tmpnam(b,e)	{ \
+	strcpy(b, "/tmp/lua_XXXXXX"); \
+	e = mkstemp(b); \
+	if (e != -1) close(e); \
+	e = (e == -1); }
+
+#else
+#define LUA_TMPNAMBUFSIZE	L_tmpnam
+#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
+#endif
+
+#endif
+
+
+/*
+@@ lua_popen spawns a new process connected to the current one through
+@* the file streams.
+** CHANGE it if you have a way to implement it in your system.
+*/
+#if defined(LUA_USE_POPEN)
+
+#define lua_popen(L,c,m)	((void)L, fflush(NULL), popen(c,m))
+#define lua_pclose(L,file)	((void)L, (pclose(file) != -1))
+
+#elif defined(LUA_WIN)
+
+#define lua_popen(L,c,m)	((void)L, _popen(c,m))
+#define lua_pclose(L,file)	((void)L, (_pclose(file) != -1))
+
+#else
+
+#define lua_popen(L,c,m)	((void)((void)c, m),  \
+		luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0)
+#define lua_pclose(L,file)		((void)((void)L, file), 0)
+
+#endif
+
+/*
+@@ LUA_DL_* define which dynamic-library system Lua should use.
+** CHANGE here if Lua has problems choosing the appropriate
+** dynamic-library system for your platform (either Windows' DLL, Mac's
+** dyld, or Unix's dlopen). If your system is some kind of Unix, there
+** is a good chance that it has dlopen, so LUA_DL_DLOPEN will work for
+** it.  To use dlopen you also need to adapt the src/Makefile (probably
+** adding -ldl to the linker options), so Lua does not select it
+** automatically.  (When you change the makefile to add -ldl, you must
+** also add -DLUA_USE_DLOPEN.)
+** If you do not want any kind of dynamic library, undefine all these
+** options.
+** By default, _WIN32 gets LUA_DL_DLL and MAC OS X gets LUA_DL_DYLD.
+*/
+#if defined(LUA_USE_DLOPEN)
+#define LUA_DL_DLOPEN
+#endif
+
+#if defined(LUA_WIN)
+#define LUA_DL_DLL
+#endif
+
+
+/*
+@@ LUAI_EXTRASPACE allows you to add user-specific data in a lua_State
+@* (the data goes just *before* the lua_State pointer).
+** CHANGE (define) this if you really need that. This value must be
+** a multiple of the maximum alignment required for your machine.
+*/
+#define LUAI_EXTRASPACE		0
+
+
+/*
+@@ luai_userstate* allow user-specific actions on threads.
+** CHANGE them if you defined LUAI_EXTRASPACE and need to do something
+** extra when a thread is created/deleted/resumed/yielded.
+*/
+#define luai_userstateopen(L)		((void)L)
+#define luai_userstateclose(L)		((void)L)
+#define luai_userstatethread(L,L1)	((void)L)
+#define luai_userstatefree(L)		((void)L)
+#define luai_userstateresume(L,n)	((void)L)
+#define luai_userstateyield(L,n)	((void)L)
+
+
+/*
+@@ LUA_INTFRMLEN is the length modifier for integer conversions
+@* in 'string.format'.
+@@ LUA_INTFRM_T is the integer type correspoding to the previous length
+@* modifier.
+** CHANGE them if your system supports long long or does not support long.
+*/
+
+#if defined(LUA_USELONGLONG)
+
+#define LUA_INTFRMLEN		"ll"
+#define LUA_INTFRM_T		long long
+
+#else
+
+#define LUA_INTFRMLEN		"l"
+#define LUA_INTFRM_T		long
+
+#endif
+
+
+
+/* =================================================================== */
+
+/*
+** Local configuration. You can use this space to add your redefinitions
+** without modifying the main part of the file.
+*/
+
+
+
+#endif
+
diff --git a/third_party/lua-src/lua-5.1.5/lualib.h b/third_party/lua-src/lua-5.1.5/lualib.h
new file mode 100644
index 00000000..469417f6
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lualib.h
@@ -0,0 +1,53 @@
+/*
+** $Id: lualib.h,v 1.36.1.1 2007/12/27 13:02:25 roberto Exp $
+** Lua standard libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lualib_h
+#define lualib_h
+
+#include "lua.h"
+
+
+/* Key to file-handle type */
+#define LUA_FILEHANDLE		"FILE*"
+
+
+#define LUA_COLIBNAME	"coroutine"
+LUALIB_API int (luaopen_base) (lua_State *L);
+
+#define LUA_TABLIBNAME	"table"
+LUALIB_API int (luaopen_table) (lua_State *L);
+
+#define LUA_IOLIBNAME	"io"
+LUALIB_API int (luaopen_io) (lua_State *L);
+
+#define LUA_OSLIBNAME	"os"
+LUALIB_API int (luaopen_os) (lua_State *L);
+
+#define LUA_STRLIBNAME	"string"
+LUALIB_API int (luaopen_string) (lua_State *L);
+
+#define LUA_MATHLIBNAME	"math"
+LUALIB_API int (luaopen_math) (lua_State *L);
+
+#define LUA_DBLIBNAME	"debug"
+LUALIB_API int (luaopen_debug) (lua_State *L);
+
+#define LUA_LOADLIBNAME	"package"
+LUALIB_API int (luaopen_package) (lua_State *L);
+
+
+/* open all previous libraries */
+LUALIB_API void (luaL_openlibs) (lua_State *L); 
+
+
+
+#ifndef lua_assert
+#define lua_assert(x)	((void)0)
+#endif
+
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lundump.c b/third_party/lua-src/lua-5.1.5/lundump.c
new file mode 100644
index 00000000..8010a457
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lundump.c
@@ -0,0 +1,227 @@
+/*
+** $Id: lundump.c,v 2.7.1.4 2008/04/04 19:51:41 roberto Exp $
+** load precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#include <string.h>
+
+#define lundump_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstring.h"
+#include "lundump.h"
+#include "lzio.h"
+
+typedef struct {
+ lua_State* L;
+ ZIO* Z;
+ Mbuffer* b;
+ const char* name;
+} LoadState;
+
+#ifdef LUAC_TRUST_BINARIES
+#define IF(c,s)
+#define error(S,s)
+#else
+#define IF(c,s)		if (c) error(S,s)
+
+static void error(LoadState* S, const char* why)
+{
+ luaO_pushfstring(S->L,"%s: %s in precompiled chunk",S->name,why);
+ luaD_throw(S->L,LUA_ERRSYNTAX);
+}
+#endif
+
+#define LoadMem(S,b,n,size)	LoadBlock(S,b,(n)*(size))
+#define	LoadByte(S)		(lu_byte)LoadChar(S)
+#define LoadVar(S,x)		LoadMem(S,&x,1,sizeof(x))
+#define LoadVector(S,b,n,size)	LoadMem(S,b,n,size)
+
+static void LoadBlock(LoadState* S, void* b, size_t size)
+{
+ size_t r=luaZ_read(S->Z,b,size);
+ IF (r!=0, "unexpected end");
+}
+
+static int LoadChar(LoadState* S)
+{
+ char x;
+ LoadVar(S,x);
+ return x;
+}
+
+static int LoadInt(LoadState* S)
+{
+ int x;
+ LoadVar(S,x);
+ IF (x<0, "bad integer");
+ return x;
+}
+
+static lua_Number LoadNumber(LoadState* S)
+{
+ lua_Number x;
+ LoadVar(S,x);
+ return x;
+}
+
+static TString* LoadString(LoadState* S)
+{
+ size_t size;
+ LoadVar(S,size);
+ if (size==0)
+  return NULL;
+ else
+ {
+  char* s=luaZ_openspace(S->L,S->b,size);
+  LoadBlock(S,s,size);
+  return luaS_newlstr(S->L,s,size-1);		/* remove trailing '\0' */
+ }
+}
+
+static void LoadCode(LoadState* S, Proto* f)
+{
+ int n=LoadInt(S);
+ f->code=luaM_newvector(S->L,n,Instruction);
+ f->sizecode=n;
+ LoadVector(S,f->code,n,sizeof(Instruction));
+}
+
+static Proto* LoadFunction(LoadState* S, TString* p);
+
+static void LoadConstants(LoadState* S, Proto* f)
+{
+ int i,n;
+ n=LoadInt(S);
+ f->k=luaM_newvector(S->L,n,TValue);
+ f->sizek=n;
+ for (i=0; i<n; i++) setnilvalue(&f->k[i]);
+ for (i=0; i<n; i++)
+ {
+  TValue* o=&f->k[i];
+  int t=LoadChar(S);
+  switch (t)
+  {
+   case LUA_TNIL:
+   	setnilvalue(o);
+	break;
+   case LUA_TBOOLEAN:
+   	setbvalue(o,LoadChar(S)!=0);
+	break;
+   case LUA_TNUMBER:
+	setnvalue(o,LoadNumber(S));
+	break;
+   case LUA_TSTRING:
+	setsvalue2n(S->L,o,LoadString(S));
+	break;
+   default:
+	error(S,"bad constant");
+	break;
+  }
+ }
+ n=LoadInt(S);
+ f->p=luaM_newvector(S->L,n,Proto*);
+ f->sizep=n;
+ for (i=0; i<n; i++) f->p[i]=NULL;
+ for (i=0; i<n; i++) f->p[i]=LoadFunction(S,f->source);
+}
+
+static void LoadDebug(LoadState* S, Proto* f)
+{
+ int i,n;
+ n=LoadInt(S);
+ f->lineinfo=luaM_newvector(S->L,n,int);
+ f->sizelineinfo=n;
+ LoadVector(S,f->lineinfo,n,sizeof(int));
+ n=LoadInt(S);
+ f->locvars=luaM_newvector(S->L,n,LocVar);
+ f->sizelocvars=n;
+ for (i=0; i<n; i++) f->locvars[i].varname=NULL;
+ for (i=0; i<n; i++)
+ {
+  f->locvars[i].varname=LoadString(S);
+  f->locvars[i].startpc=LoadInt(S);
+  f->locvars[i].endpc=LoadInt(S);
+ }
+ n=LoadInt(S);
+ f->upvalues=luaM_newvector(S->L,n,TString*);
+ f->sizeupvalues=n;
+ for (i=0; i<n; i++) f->upvalues[i]=NULL;
+ for (i=0; i<n; i++) f->upvalues[i]=LoadString(S);
+}
+
+static Proto* LoadFunction(LoadState* S, TString* p)
+{
+ Proto* f;
+ if (++S->L->nCcalls > LUAI_MAXCCALLS) error(S,"code too deep");
+ f=luaF_newproto(S->L);
+ setptvalue2s(S->L,S->L->top,f); incr_top(S->L);
+ f->source=LoadString(S); if (f->source==NULL) f->source=p;
+ f->linedefined=LoadInt(S);
+ f->lastlinedefined=LoadInt(S);
+ f->nups=LoadByte(S);
+ f->numparams=LoadByte(S);
+ f->is_vararg=LoadByte(S);
+ f->maxstacksize=LoadByte(S);
+ LoadCode(S,f);
+ LoadConstants(S,f);
+ LoadDebug(S,f);
+ IF (!luaG_checkcode(f), "bad code");
+ S->L->top--;
+ S->L->nCcalls--;
+ return f;
+}
+
+static void LoadHeader(LoadState* S)
+{
+ char h[LUAC_HEADERSIZE];
+ char s[LUAC_HEADERSIZE];
+ luaU_header(h);
+ LoadBlock(S,s,LUAC_HEADERSIZE);
+ IF (memcmp(h,s,LUAC_HEADERSIZE)!=0, "bad header");
+}
+
+/*
+** load precompiled chunk
+*/
+Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name)
+{
+ LoadState S;
+ if (*name=='@' || *name=='=')
+  S.name=name+1;
+ else if (*name==LUA_SIGNATURE[0])
+  S.name="binary string";
+ else
+  S.name=name;
+ S.L=L;
+ S.Z=Z;
+ S.b=buff;
+ LoadHeader(&S);
+ return LoadFunction(&S,luaS_newliteral(L,"=?"));
+}
+
+/*
+* make header
+*/
+void luaU_header (char* h)
+{
+ int x=1;
+ memcpy(h,LUA_SIGNATURE,sizeof(LUA_SIGNATURE)-1);
+ h+=sizeof(LUA_SIGNATURE)-1;
+ *h++=(char)LUAC_VERSION;
+ *h++=(char)LUAC_FORMAT;
+ *h++=(char)*(char*)&x;				/* endianness */
+ *h++=(char)sizeof(int);
+ *h++=(char)sizeof(size_t);
+ *h++=(char)sizeof(Instruction);
+ *h++=(char)sizeof(lua_Number);
+ *h++=(char)(((lua_Number)0.5)==0);		/* is lua_Number integral? */
+}
diff --git a/third_party/lua-src/lua-5.1.5/lundump.h b/third_party/lua-src/lua-5.1.5/lundump.h
new file mode 100644
index 00000000..c80189db
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lundump.h
@@ -0,0 +1,36 @@
+/*
+** $Id: lundump.h,v 1.37.1.1 2007/12/27 13:02:25 roberto Exp $
+** load precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lundump_h
+#define lundump_h
+
+#include "lobject.h"
+#include "lzio.h"
+
+/* load one chunk; from lundump.c */
+LUAI_FUNC Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name);
+
+/* make header; from lundump.c */
+LUAI_FUNC void luaU_header (char* h);
+
+/* dump one chunk; from ldump.c */
+LUAI_FUNC int luaU_dump (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip);
+
+#ifdef luac_c
+/* print one chunk; from print.c */
+LUAI_FUNC void luaU_print (const Proto* f, int full);
+#endif
+
+/* for header of binary files -- this is Lua 5.1 */
+#define LUAC_VERSION		0x51
+
+/* for header of binary files -- this is the official format */
+#define LUAC_FORMAT		0
+
+/* size of header of binary files */
+#define LUAC_HEADERSIZE		12
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lvm.c b/third_party/lua-src/lua-5.1.5/lvm.c
new file mode 100644
index 00000000..50c89e75
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lvm.c
@@ -0,0 +1,808 @@
+/*
+** $Id: lvm.c,v 2.63.1.5 2011/08/17 20:43:11 roberto Exp $
+** Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lvm_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+
+/* limit for table tag-method chains (to avoid loops) */
+#define MAXTAGLOOP	100
+
+
+const TValue *luaV_tonumber (const TValue *obj, TValue *n) {
+  lua_Number num;
+  if (ttisnumber(obj)) return obj;
+  if (ttisstring(obj) && luaO_str2d(svalue(obj), &num)) {
+    setnvalue(n, num);
+    return n;
+  }
+  else
+    return NULL;
+}
+
+
+int luaV_tostring (lua_State *L, StkId obj) {
+  if (!ttisnumber(obj))
+    return 0;
+  else {
+    char s[LUAI_MAXNUMBER2STR];
+    lua_Number n = nvalue(obj);
+    lua_number2str(s, n);
+    setsvalue2s(L, obj, luaS_new(L, s));
+    return 1;
+  }
+}
+
+
+static void traceexec (lua_State *L, const Instruction *pc) {
+  lu_byte mask = L->hookmask;
+  const Instruction *oldpc = L->savedpc;
+  L->savedpc = pc;
+  if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) {
+    resethookcount(L);
+    luaD_callhook(L, LUA_HOOKCOUNT, -1);
+  }
+  if (mask & LUA_MASKLINE) {
+    Proto *p = ci_func(L->ci)->l.p;
+    int npc = pcRel(pc, p);
+    int newline = getline(p, npc);
+    /* call linehook when enter a new function, when jump back (loop),
+       or when enter a new line */
+    if (npc == 0 || pc <= oldpc || newline != getline(p, pcRel(oldpc, p)))
+      luaD_callhook(L, LUA_HOOKLINE, newline);
+  }
+}
+
+
+static void callTMres (lua_State *L, StkId res, const TValue *f,
+                        const TValue *p1, const TValue *p2) {
+  ptrdiff_t result = savestack(L, res);
+  setobj2s(L, L->top, f);  /* push function */
+  setobj2s(L, L->top+1, p1);  /* 1st argument */
+  setobj2s(L, L->top+2, p2);  /* 2nd argument */
+  luaD_checkstack(L, 3);
+  L->top += 3;
+  luaD_call(L, L->top - 3, 1);
+  res = restorestack(L, result);
+  L->top--;
+  setobjs2s(L, res, L->top);
+}
+
+
+
+static void callTM (lua_State *L, const TValue *f, const TValue *p1,
+                    const TValue *p2, const TValue *p3) {
+  setobj2s(L, L->top, f);  /* push function */
+  setobj2s(L, L->top+1, p1);  /* 1st argument */
+  setobj2s(L, L->top+2, p2);  /* 2nd argument */
+  setobj2s(L, L->top+3, p3);  /* 3th argument */
+  luaD_checkstack(L, 4);
+  L->top += 4;
+  luaD_call(L, L->top - 4, 0);
+}
+
+
+void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) {
+  int loop;
+  for (loop = 0; loop < MAXTAGLOOP; loop++) {
+    const TValue *tm;
+    if (ttistable(t)) {  /* `t' is a table? */
+      Table *h = hvalue(t);
+      const TValue *res = luaH_get(h, key); /* do a primitive get */
+      if (!ttisnil(res) ||  /* result is no nil? */
+          (tm = fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */
+        setobj2s(L, val, res);
+        return;
+      }
+      /* else will try the tag method */
+    }
+    else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX)))
+      luaG_typeerror(L, t, "index");
+    if (ttisfunction(tm)) {
+      callTMres(L, val, tm, t, key);
+      return;
+    }
+    t = tm;  /* else repeat with `tm' */ 
+  }
+  luaG_runerror(L, "loop in gettable");
+}
+
+
+void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
+  int loop;
+  TValue temp;
+  for (loop = 0; loop < MAXTAGLOOP; loop++) {
+    const TValue *tm;
+    if (ttistable(t)) {  /* `t' is a table? */
+      Table *h = hvalue(t);
+      TValue *oldval = luaH_set(L, h, key); /* do a primitive set */
+      if (!ttisnil(oldval) ||  /* result is no nil? */
+          (tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
+        setobj2t(L, oldval, val);
+        h->flags = 0;
+        luaC_barriert(L, h, val);
+        return;
+      }
+      /* else will try the tag method */
+    }
+    else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
+      luaG_typeerror(L, t, "index");
+    if (ttisfunction(tm)) {
+      callTM(L, tm, t, key, val);
+      return;
+    }
+    /* else repeat with `tm' */
+    setobj(L, &temp, tm);  /* avoid pointing inside table (may rehash) */
+    t = &temp;
+  }
+  luaG_runerror(L, "loop in settable");
+}
+
+
+static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2,
+                       StkId res, TMS event) {
+  const TValue *tm = luaT_gettmbyobj(L, p1, event);  /* try first operand */
+  if (ttisnil(tm))
+    tm = luaT_gettmbyobj(L, p2, event);  /* try second operand */
+  if (ttisnil(tm)) return 0;
+  callTMres(L, res, tm, p1, p2);
+  return 1;
+}
+
+
+static const TValue *get_compTM (lua_State *L, Table *mt1, Table *mt2,
+                                  TMS event) {
+  const TValue *tm1 = fasttm(L, mt1, event);
+  const TValue *tm2;
+  if (tm1 == NULL) return NULL;  /* no metamethod */
+  if (mt1 == mt2) return tm1;  /* same metatables => same metamethods */
+  tm2 = fasttm(L, mt2, event);
+  if (tm2 == NULL) return NULL;  /* no metamethod */
+  if (luaO_rawequalObj(tm1, tm2))  /* same metamethods? */
+    return tm1;
+  return NULL;
+}
+
+
+static int call_orderTM (lua_State *L, const TValue *p1, const TValue *p2,
+                         TMS event) {
+  const TValue *tm1 = luaT_gettmbyobj(L, p1, event);
+  const TValue *tm2;
+  if (ttisnil(tm1)) return -1;  /* no metamethod? */
+  tm2 = luaT_gettmbyobj(L, p2, event);
+  if (!luaO_rawequalObj(tm1, tm2))  /* different metamethods? */
+    return -1;
+  callTMres(L, L->top, tm1, p1, p2);
+  return !l_isfalse(L->top);
+}
+
+
+static int l_strcmp (const TString *ls, const TString *rs) {
+  const char *l = getstr(ls);
+  size_t ll = ls->tsv.len;
+  const char *r = getstr(rs);
+  size_t lr = rs->tsv.len;
+  for (;;) {
+    int temp = strcoll(l, r);
+    if (temp != 0) return temp;
+    else {  /* strings are equal up to a `\0' */
+      size_t len = strlen(l);  /* index of first `\0' in both strings */
+      if (len == lr)  /* r is finished? */
+        return (len == ll) ? 0 : 1;
+      else if (len == ll)  /* l is finished? */
+        return -1;  /* l is smaller than r (because r is not finished) */
+      /* both strings longer than `len'; go on comparing (after the `\0') */
+      len++;
+      l += len; ll -= len; r += len; lr -= len;
+    }
+  }
+}
+
+
+int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
+  int res;
+  if (ttype(l) != ttype(r))
+    return luaG_ordererror(L, l, r);
+  else if (ttisnumber(l))
+    return luai_numlt(nvalue(l), nvalue(r));
+  else if (ttisstring(l))
+    return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0;
+  else if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
+    return res;
+  return luaG_ordererror(L, l, r);
+}
+
+
+static int lessequal (lua_State *L, const TValue *l, const TValue *r) {
+  int res;
+  if (ttype(l) != ttype(r))
+    return luaG_ordererror(L, l, r);
+  else if (ttisnumber(l))
+    return luai_numle(nvalue(l), nvalue(r));
+  else if (ttisstring(l))
+    return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0;
+  else if ((res = call_orderTM(L, l, r, TM_LE)) != -1)  /* first try `le' */
+    return res;
+  else if ((res = call_orderTM(L, r, l, TM_LT)) != -1)  /* else try `lt' */
+    return !res;
+  return luaG_ordererror(L, l, r);
+}
+
+
+int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2) {
+  const TValue *tm;
+  lua_assert(ttype(t1) == ttype(t2));
+  switch (ttype(t1)) {
+    case LUA_TNIL: return 1;
+    case LUA_TNUMBER: return luai_numeq(nvalue(t1), nvalue(t2));
+    case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2);  /* true must be 1 !! */
+    case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
+    case LUA_TUSERDATA: {
+      if (uvalue(t1) == uvalue(t2)) return 1;
+      tm = get_compTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable,
+                         TM_EQ);
+      break;  /* will try TM */
+    }
+    case LUA_TTABLE: {
+      if (hvalue(t1) == hvalue(t2)) return 1;
+      tm = get_compTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ);
+      break;  /* will try TM */
+    }
+    default: return gcvalue(t1) == gcvalue(t2);
+  }
+  if (tm == NULL) return 0;  /* no TM? */
+  callTMres(L, L->top, tm, t1, t2);  /* call TM */
+  return !l_isfalse(L->top);
+}
+
+
+void luaV_concat (lua_State *L, int total, int last) {
+  do {
+    StkId top = L->base + last + 1;
+    int n = 2;  /* number of elements handled in this pass (at least 2) */
+    if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) {
+      if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT))
+        luaG_concaterror(L, top-2, top-1);
+    } else if (tsvalue(top-1)->len == 0)  /* second op is empty? */
+      (void)tostring(L, top - 2);  /* result is first op (as string) */
+    else {
+      /* at least two string values; get as many as possible */
+      size_t tl = tsvalue(top-1)->len;
+      char *buffer;
+      int i;
+      /* collect total length */
+      for (n = 1; n < total && tostring(L, top-n-1); n++) {
+        size_t l = tsvalue(top-n-1)->len;
+        if (l >= MAX_SIZET - tl) luaG_runerror(L, "string length overflow");
+        tl += l;
+      }
+      buffer = luaZ_openspace(L, &G(L)->buff, tl);
+      tl = 0;
+      for (i=n; i>0; i--) {  /* concat all strings */
+        size_t l = tsvalue(top-i)->len;
+        memcpy(buffer+tl, svalue(top-i), l);
+        tl += l;
+      }
+      setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
+    }
+    total -= n-1;  /* got `n' strings to create 1 new */
+    last -= n-1;
+  } while (total > 1);  /* repeat until only 1 result left */
+}
+
+
+static void Arith (lua_State *L, StkId ra, const TValue *rb,
+                   const TValue *rc, TMS op) {
+  TValue tempb, tempc;
+  const TValue *b, *c;
+  if ((b = luaV_tonumber(rb, &tempb)) != NULL &&
+      (c = luaV_tonumber(rc, &tempc)) != NULL) {
+    lua_Number nb = nvalue(b), nc = nvalue(c);
+    switch (op) {
+      case TM_ADD: setnvalue(ra, luai_numadd(nb, nc)); break;
+      case TM_SUB: setnvalue(ra, luai_numsub(nb, nc)); break;
+      case TM_MUL: setnvalue(ra, luai_nummul(nb, nc)); break;
+      case TM_DIV: setnvalue(ra, luai_numdiv(nb, nc)); break;
+      case TM_MOD: setnvalue(ra, luai_nummod(nb, nc)); break;
+      case TM_POW: setnvalue(ra, luai_numpow(nb, nc)); break;
+      case TM_UNM: setnvalue(ra, luai_numunm(nb)); break;
+      default: lua_assert(0); break;
+    }
+  }
+  else if (!call_binTM(L, rb, rc, ra, op))
+    luaG_aritherror(L, rb, rc);
+}
+
+
+
+/*
+** some macros for common tasks in `luaV_execute'
+*/
+
+#define runtime_check(L, c)	{ if (!(c)) break; }
+
+#define RA(i)	(base+GETARG_A(i))
+/* to be used after possible stack reallocation */
+#define RB(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgR, base+GETARG_B(i))
+#define RC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i))
+#define RKB(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \
+	ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i))
+#define RKC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \
+	ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i))
+#define KBx(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgK, k+GETARG_Bx(i))
+
+
+#define dojump(L,pc,i)	{(pc) += (i); luai_threadyield(L);}
+
+
+#define Protect(x)	{ L->savedpc = pc; {x;}; base = L->base; }
+
+
+#define arith_op(op,tm) { \
+        TValue *rb = RKB(i); \
+        TValue *rc = RKC(i); \
+        if (ttisnumber(rb) && ttisnumber(rc)) { \
+          lua_Number nb = nvalue(rb), nc = nvalue(rc); \
+          setnvalue(ra, op(nb, nc)); \
+        } \
+        else \
+          Protect(Arith(L, ra, rb, rc, tm)); \
+      }
+
+
+
+void luaV_execute (lua_State *L, int nexeccalls) {
+  LClosure *cl;
+  StkId base;
+  TValue *k;
+  const Instruction *pc;
+ reentry:  /* entry point */
+  lua_assert(isLua(L->ci));
+  pc = L->savedpc;
+  cl = &clvalue(L->ci->func)->l;
+  base = L->base;
+  k = cl->p->k;
+  /* main loop of interpreter */
+  for (;;) {
+    const Instruction i = *pc++;
+    StkId ra;
+    if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) &&
+        (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) {
+      traceexec(L, pc);
+      if (L->status == LUA_YIELD) {  /* did hook yield? */
+        L->savedpc = pc - 1;
+        return;
+      }
+      base = L->base;
+    }
+    /* warning!! several calls may realloc the stack and invalidate `ra' */
+    ra = RA(i);
+    lua_assert(base == L->base && L->base == L->ci->base);
+    lua_assert(base <= L->top && L->top <= L->stack + L->stacksize);
+    lua_assert(L->top == L->ci->top || luaG_checkopenop(i));
+    switch (GET_OPCODE(i)) {
+      case OP_MOVE: {
+        setobjs2s(L, ra, RB(i));
+        continue;
+      }
+      case OP_LOADK: {
+        setobj2s(L, ra, KBx(i));
+        continue;
+      }
+      case OP_LOADBOOL: {
+        setbvalue(ra, GETARG_B(i));
+        if (GETARG_C(i)) pc++;  /* skip next instruction (if C) */
+        continue;
+      }
+      case OP_LOADNIL: {
+        TValue *rb = RB(i);
+        do {
+          setnilvalue(rb--);
+        } while (rb >= ra);
+        continue;
+      }
+      case OP_GETUPVAL: {
+        int b = GETARG_B(i);
+        setobj2s(L, ra, cl->upvals[b]->v);
+        continue;
+      }
+      case OP_GETGLOBAL: {
+        TValue g;
+        TValue *rb = KBx(i);
+        sethvalue(L, &g, cl->env);
+        lua_assert(ttisstring(rb));
+        Protect(luaV_gettable(L, &g, rb, ra));
+        continue;
+      }
+      case OP_GETTABLE: {
+        Protect(luaV_gettable(L, RB(i), RKC(i), ra));
+        continue;
+      }
+      case OP_SETGLOBAL: {
+        TValue g;
+        sethvalue(L, &g, cl->env);
+        lua_assert(ttisstring(KBx(i)));
+        Protect(luaV_settable(L, &g, KBx(i), ra));
+        continue;
+      }
+      case OP_SETUPVAL: {
+        UpVal *uv = cl->upvals[GETARG_B(i)];
+        setobj(L, uv->v, ra);
+        luaC_barrier(L, uv, ra);
+        continue;
+      }
+      case OP_SETTABLE: {
+        Protect(luaV_settable(L, ra, RKB(i), RKC(i)));
+        continue;
+      }
+      case OP_NEWTABLE: {
+        int b = GETARG_B(i);
+        int c = GETARG_C(i);
+        sethvalue(L, ra, luaH_new(L, luaO_fb2int(b), luaO_fb2int(c)));
+        Protect(luaC_checkGC(L));
+        continue;
+      }
+      case OP_SELF: {
+        StkId rb = RB(i);
+        setobjs2s(L, ra+1, rb);
+        Protect(luaV_gettable(L, rb, RKC(i), ra));
+        continue;
+      }
+      case OP_ADD: {
+        arith_op(luai_numadd, TM_ADD);
+        continue;
+      }
+      case OP_SUB: {
+        arith_op(luai_numsub, TM_SUB);
+        continue;
+      }
+      case OP_MUL: {
+        arith_op(luai_nummul, TM_MUL);
+        continue;
+      }
+      case OP_DIV: {
+        arith_op(luai_numdiv, TM_DIV);
+        continue;
+      }
+      case OP_MOD: {
+        arith_op(luai_nummod, TM_MOD);
+        continue;
+      }
+      case OP_POW: {
+        arith_op(luai_numpow, TM_POW);
+        continue;
+      }
+      case OP_UNM: {
+        TValue *rb = RB(i);
+        if (ttisnumber(rb)) {
+          lua_Number nb = nvalue(rb);
+          setnvalue(ra, luai_numunm(nb));
+        }
+        else {
+          Protect(Arith(L, ra, rb, rb, TM_UNM));
+        }
+        continue;
+      }
+      case OP_NOT: {
+        int res = l_isfalse(RB(i));  /* next assignment may change this value */
+        setbvalue(ra, res);
+        continue;
+      }
+      case OP_LEN: {
+        const TValue *rb = RB(i);
+        switch (ttype(rb)) {
+          case LUA_TTABLE: {
+            setnvalue(ra, cast_num(luaH_getn(hvalue(rb))));
+            break;
+          }
+          case LUA_TSTRING: {
+            setnvalue(ra, cast_num(tsvalue(rb)->len));
+            break;
+          }
+          default: {  /* try metamethod */
+            Protect(
+              if (!call_binTM(L, rb, luaO_nilobject, ra, TM_LEN))
+                luaG_typeerror(L, rb, "get length of");
+            )
+          }
+        }
+        continue;
+      }
+      case OP_CONCAT: {
+        int b = GETARG_B(i);
+        int c = GETARG_C(i);
+        Protect(luaV_concat(L, c-b+1, c); luaC_checkGC(L));
+        setobjs2s(L, RA(i), base+b);
+        continue;
+      }
+      case OP_JMP: {
+        dojump(L, pc, GETARG_sBx(i));
+        continue;
+      }
+      case OP_EQ: {
+        TValue *rb = RKB(i);
+        TValue *rc = RKC(i);
+        Protect(
+          if (equalobj(L, rb, rc) == GETARG_A(i))
+            dojump(L, pc, GETARG_sBx(*pc));
+        )
+        pc++;
+        continue;
+      }
+      case OP_LT: {
+        Protect(
+          if (luaV_lessthan(L, RKB(i), RKC(i)) == GETARG_A(i))
+            dojump(L, pc, GETARG_sBx(*pc));
+        )
+        pc++;
+        continue;
+      }
+      case OP_LE: {
+        Protect(
+          if (lessequal(L, RKB(i), RKC(i)) == GETARG_A(i))
+            dojump(L, pc, GETARG_sBx(*pc));
+        )
+        pc++;
+        continue;
+      }
+      case OP_TEST: {
+        if (l_isfalse(ra) != GETARG_C(i))
+          dojump(L, pc, GETARG_sBx(*pc));
+        pc++;
+        continue;
+      }
+      case OP_TESTSET: {
+        TValue *rb = RB(i);
+        if (l_isfalse(rb) != GETARG_C(i)) {
+          setobjs2s(L, ra, rb);
+          dojump(L, pc, GETARG_sBx(*pc));
+        }
+        pc++;
+        continue;
+      }
+      case OP_CALL: {
+        int b = GETARG_B(i);
+        int nresults = GETARG_C(i) - 1;
+        if (b != 0) L->top = ra+b;  /* else previous instruction set top */
+        L->savedpc = pc;
+        switch (luaD_precall(L, ra, nresults)) {
+          case PCRLUA: {
+            nexeccalls++;
+            goto reentry;  /* restart luaV_execute over new Lua function */
+          }
+          case PCRC: {
+            /* it was a C function (`precall' called it); adjust results */
+            if (nresults >= 0) L->top = L->ci->top;
+            base = L->base;
+            continue;
+          }
+          default: {
+            return;  /* yield */
+          }
+        }
+      }
+      case OP_TAILCALL: {
+        int b = GETARG_B(i);
+        if (b != 0) L->top = ra+b;  /* else previous instruction set top */
+        L->savedpc = pc;
+        lua_assert(GETARG_C(i) - 1 == LUA_MULTRET);
+        switch (luaD_precall(L, ra, LUA_MULTRET)) {
+          case PCRLUA: {
+            /* tail call: put new frame in place of previous one */
+            CallInfo *ci = L->ci - 1;  /* previous frame */
+            int aux;
+            StkId func = ci->func;
+            StkId pfunc = (ci+1)->func;  /* previous function index */
+            if (L->openupval) luaF_close(L, ci->base);
+            L->base = ci->base = ci->func + ((ci+1)->base - pfunc);
+            for (aux = 0; pfunc+aux < L->top; aux++)  /* move frame down */
+              setobjs2s(L, func+aux, pfunc+aux);
+            ci->top = L->top = func+aux;  /* correct top */
+            lua_assert(L->top == L->base + clvalue(func)->l.p->maxstacksize);
+            ci->savedpc = L->savedpc;
+            ci->tailcalls++;  /* one more call lost */
+            L->ci--;  /* remove new frame */
+            goto reentry;
+          }
+          case PCRC: {  /* it was a C function (`precall' called it) */
+            base = L->base;
+            continue;
+          }
+          default: {
+            return;  /* yield */
+          }
+        }
+      }
+      case OP_RETURN: {
+        int b = GETARG_B(i);
+        if (b != 0) L->top = ra+b-1;
+        if (L->openupval) luaF_close(L, base);
+        L->savedpc = pc;
+        b = luaD_poscall(L, ra);
+        if (--nexeccalls == 0)  /* was previous function running `here'? */
+          return;  /* no: return */
+        else {  /* yes: continue its execution */
+          if (b) L->top = L->ci->top;
+          lua_assert(isLua(L->ci));
+          lua_assert(GET_OPCODE(*((L->ci)->savedpc - 1)) == OP_CALL);
+          goto reentry;
+        }
+      }
+      case OP_FORLOOP: {
+        lua_Number step = nvalue(ra+2);
+        lua_Number idx = luai_numadd(nvalue(ra), step); /* increment index */
+        lua_Number limit = nvalue(ra+1);
+        if (luai_numlt(0, step) ? luai_numle(idx, limit)
+                                : luai_numle(limit, idx)) {
+          dojump(L, pc, GETARG_sBx(i));  /* jump back */
+          setnvalue(ra, idx);  /* update internal index... */
+          setnvalue(ra+3, idx);  /* ...and external index */
+        }
+        continue;
+      }
+      case OP_FORPREP: {
+        const TValue *init = ra;
+        const TValue *plimit = ra+1;
+        const TValue *pstep = ra+2;
+        L->savedpc = pc;  /* next steps may throw errors */
+        if (!tonumber(init, ra))
+          luaG_runerror(L, LUA_QL("for") " initial value must be a number");
+        else if (!tonumber(plimit, ra+1))
+          luaG_runerror(L, LUA_QL("for") " limit must be a number");
+        else if (!tonumber(pstep, ra+2))
+          luaG_runerror(L, LUA_QL("for") " step must be a number");
+        setnvalue(ra, luai_numsub(nvalue(ra), nvalue(pstep)));
+        dojump(L, pc, GETARG_sBx(i));
+        continue;
+      }
+      case OP_TFORLOOP: {
+        StkId cb = ra + 3;  /* call base */
+        /* BENILLA: Lua 5.0's OP_TFORPREP, folded into the loop opcode.
+        ** See third_party/lua-src/BENILLA.md and benilla decision 1215.
+        **
+        ** 5.0 ran this ONCE at loop entry in its own opcode (index 30, 157 bytes, verified in
+        ** the 1.12.1 client at 0x6f94a2): when a generic-for's generator is a table, the table
+        ** becomes the STATE and the generator becomes the global `next`. 5.1 deleted the opcode,
+        ** so `for k, v in someTable do` -- which 183 of 218 corpus addons are reached by, and
+        ** which is the first session-start error for 60 of them -- raises "attempt to call a
+        ** table value".
+        **
+        ** Placing it here is timing-exact rather than approximate: 5.1's parser emits a JMP
+        ** straight to this instruction, so the top of TFORLOOP IS 5.0's prep point, before the
+        ** first call. It is self-clearing -- after one pass `ra` holds a function, so the test
+        ** fails on every later iteration -- which is what makes an entry-only rule safe to
+        ** express as a per-iteration check.
+        **
+        ** Three details are the client's, not conveniences, each byte-verified in wow-5875-re
+        ** system/ui/scratch/lua-generic-for.md:
+        **   - the test is a BARE TYPE TAG equality. The handler makes no metatable access at
+        **     all, so a table carrying __call still gets `next` and never reaches tryfuncTM.
+        **     "not callable" and "no __call" are different conditions and both diverge here.
+        **   - the callee is the GLOBAL `next`, read RAW (no __index) from the thread's own
+        **     globals table, fetched fresh at every loop entry. An addon that assigns
+        **     `next = myfn` therefore changes every later generic-for in the session. That is
+        **     observable, and it is reproduced rather than improved on.
+        **   - userdata is NOT substituted (tag mismatch), so it still reaches __call, and a
+        **     nil/string/number generator still raises on iteration 1, not at entry.
+        **
+        ** KNOWN, MEASURED DIVERGENCE THIS DOES NOT CLOSE. 5.0's generic-for has two hidden
+        ** locals, not three: ra+2 is the first user variable AND the control, so assigning to it
+        ** inside the body changes what the next iteration is asked for. 5.1 gives the control
+        ** its own slot, and this patch does not move it -- that is a register-layout property
+        ** owned by the code generator, not by this handler. Measured before shipping
+        ** (scripts/generic-for-control-census.py): 95 addons contain the shape, concentrated in
+        ** two files nearly everything embeds -- Dewdrop-2.0.lua (123 sites) and AceEvent-2.0.lua
+        ** (113). Recorded rather than hidden; closing it is a separate change.
+        */
+        if (ttistable(ra)) {
+          setobjs2s(L, ra+1, ra);
+          setobj2s(L, ra, luaH_getstr(hvalue(gt(L)), luaS_new(L, "next")));
+        }
+        setobjs2s(L, cb+2, ra+2);
+        setobjs2s(L, cb+1, ra+1);
+        setobjs2s(L, cb, ra);
+        L->top = cb+3;  /* func. + 2 args (state and index) */
+        Protect(luaD_call(L, cb, GETARG_C(i)));
+        L->top = L->ci->top;
+        cb = RA(i) + 3;  /* previous call may change the stack */
+        if (!ttisnil(cb)) {  /* continue loop? */
+          setobjs2s(L, cb-1, cb);  /* save control variable */
+          dojump(L, pc, GETARG_sBx(*pc));  /* jump back */
+        }
+        pc++;
+        continue;
+      }
+      case OP_SETLIST: {
+        int n = GETARG_B(i);
+        int c = GETARG_C(i);
+        int last;
+        Table *h;
+        if (n == 0) {
+          n = cast_int(L->top - ra) - 1;
+          L->top = L->ci->top;
+        }
+        if (c == 0) c = cast_int(*pc++);
+        runtime_check(L, ttistable(ra));
+        h = hvalue(ra);
+        last = ((c-1)*LFIELDS_PER_FLUSH) + n;
+        if (last > h->sizearray)  /* needs more space? */
+          luaH_resizearray(L, h, last);  /* pre-alloc it at once */
+        for (; n > 0; n--) {
+          TValue *val = ra+n;
+          setobj2t(L, luaH_setnum(L, h, last--), val);
+          luaC_barriert(L, h, val);
+        }
+        continue;
+      }
+      case OP_CLOSE: {
+        luaF_close(L, ra);
+        continue;
+      }
+      case OP_CLOSURE: {
+        Proto *p;
+        Closure *ncl;
+        int nup, j;
+        p = cl->p->p[GETARG_Bx(i)];
+        nup = p->nups;
+        ncl = luaF_newLclosure(L, nup, cl->env);
+        ncl->l.p = p;
+        for (j=0; j<nup; j++, pc++) {
+          if (GET_OPCODE(*pc) == OP_GETUPVAL)
+            ncl->l.upvals[j] = cl->upvals[GETARG_B(*pc)];
+          else {
+            lua_assert(GET_OPCODE(*pc) == OP_MOVE);
+            ncl->l.upvals[j] = luaF_findupval(L, base + GETARG_B(*pc));
+          }
+        }
+        setclvalue(L, ra, ncl);
+        Protect(luaC_checkGC(L));
+        continue;
+      }
+      case OP_VARARG: {
+        int b = GETARG_B(i) - 1;
+        int j;
+        CallInfo *ci = L->ci;
+        int n = cast_int(ci->base - ci->func) - cl->p->numparams - 1;
+        if (b == LUA_MULTRET) {
+          Protect(luaD_checkstack(L, n));
+          ra = RA(i);  /* previous call may change the stack */
+          b = n;
+          L->top = ra + n;
+        }
+        for (j = 0; j < b; j++) {
+          if (j < n) {
+            setobjs2s(L, ra + j, ci->base - n + j);
+          }
+          else {
+            setnilvalue(ra + j);
+          }
+        }
+        continue;
+      }
+    }
+  }
+}
+
diff --git a/third_party/lua-src/lua-5.1.5/lvm.h b/third_party/lua-src/lua-5.1.5/lvm.h
new file mode 100644
index 00000000..bfe4f567
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lvm.h
@@ -0,0 +1,36 @@
+/*
+** $Id: lvm.h,v 2.5.1.1 2007/12/27 13:02:25 roberto Exp $
+** Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lvm_h
+#define lvm_h
+
+
+#include "ldo.h"
+#include "lobject.h"
+#include "ltm.h"
+
+
+#define tostring(L,o) ((ttype(o) == LUA_TSTRING) || (luaV_tostring(L, o)))
+
+#define tonumber(o,n)	(ttype(o) == LUA_TNUMBER || \
+                         (((o) = luaV_tonumber(o,n)) != NULL))
+
+#define equalobj(L,o1,o2) \
+	(ttype(o1) == ttype(o2) && luaV_equalval(L, o1, o2))
+
+
+LUAI_FUNC int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r);
+LUAI_FUNC int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2);
+LUAI_FUNC const TValue *luaV_tonumber (const TValue *obj, TValue *n);
+LUAI_FUNC int luaV_tostring (lua_State *L, StkId obj);
+LUAI_FUNC void luaV_gettable (lua_State *L, const TValue *t, TValue *key,
+                                            StkId val);
+LUAI_FUNC void luaV_settable (lua_State *L, const TValue *t, TValue *key,
+                                            StkId val);
+LUAI_FUNC void luaV_execute (lua_State *L, int nexeccalls);
+LUAI_FUNC void luaV_concat (lua_State *L, int total, int last);
+
+#endif
diff --git a/third_party/lua-src/lua-5.1.5/lzio.c b/third_party/lua-src/lua-5.1.5/lzio.c
new file mode 100644
index 00000000..293edd59
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lzio.c
@@ -0,0 +1,82 @@
+/*
+** $Id: lzio.c,v 1.31.1.1 2007/12/27 13:02:25 roberto Exp $
+** a generic input stream interface
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#define lzio_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "llimits.h"
+#include "lmem.h"
+#include "lstate.h"
+#include "lzio.h"
+
+
+int luaZ_fill (ZIO *z) {
+  size_t size;
+  lua_State *L = z->L;
+  const char *buff;
+  lua_unlock(L);
+  buff = z->reader(L, z->data, &size);
+  lua_lock(L);
+  if (buff == NULL || size == 0) return EOZ;
+  z->n = size - 1;
+  z->p = buff;
+  return char2int(*(z->p++));
+}
+
+
+int luaZ_lookahead (ZIO *z) {
+  if (z->n == 0) {
+    if (luaZ_fill(z) == EOZ)
+      return EOZ;
+    else {
+      z->n++;  /* luaZ_fill removed first byte; put back it */
+      z->p--;
+    }
+  }
+  return char2int(*z->p);
+}
+
+
+void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) {
+  z->L = L;
+  z->reader = reader;
+  z->data = data;
+  z->n = 0;
+  z->p = NULL;
+}
+
+
+/* --------------------------------------------------------------- read --- */
+size_t luaZ_read (ZIO *z, void *b, size_t n) {
+  while (n) {
+    size_t m;
+    if (luaZ_lookahead(z) == EOZ)
+      return n;  /* return number of missing bytes */
+    m = (n <= z->n) ? n : z->n;  /* min. between n and z->n */
+    memcpy(b, z->p, m);
+    z->n -= m;
+    z->p += m;
+    b = (char *)b + m;
+    n -= m;
+  }
+  return 0;
+}
+
+/* ------------------------------------------------------------------------ */
+char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n) {
+  if (n > buff->buffsize) {
+    if (n < LUA_MINBUFFER) n = LUA_MINBUFFER;
+    luaZ_resizebuffer(L, buff, n);
+  }
+  return buff->buffer;
+}
+
+
diff --git a/third_party/lua-src/lua-5.1.5/lzio.h b/third_party/lua-src/lua-5.1.5/lzio.h
new file mode 100644
index 00000000..51d695d8
--- /dev/null
+++ b/third_party/lua-src/lua-5.1.5/lzio.h
@@ -0,0 +1,67 @@
+/*
+** $Id: lzio.h,v 1.21.1.1 2007/12/27 13:02:25 roberto Exp $
+** Buffered streams
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lzio_h
+#define lzio_h
+
+#include "lua.h"
+
+#include "lmem.h"
+
+
+#define EOZ	(-1)			/* end of stream */
+
+typedef struct Zio ZIO;
+
+#define char2int(c)	cast(int, cast(unsigned char, (c)))
+
+#define zgetc(z)  (((z)->n--)>0 ?  char2int(*(z)->p++) : luaZ_fill(z))
+
+typedef struct Mbuffer {
+  char *buffer;
+  size_t n;
+  size_t buffsize;
+} Mbuffer;
+
+#define luaZ_initbuffer(L, buff) ((buff)->buffer = NULL, (buff)->buffsize = 0)
+
+#define luaZ_buffer(buff)	((buff)->buffer)
+#define luaZ_sizebuffer(buff)	((buff)->buffsize)
+#define luaZ_bufflen(buff)	((buff)->n)
+
+#define luaZ_resetbuffer(buff) ((buff)->n = 0)
+
+
+#define luaZ_resizebuffer(L, buff, size) \
+	(luaM_reallocvector(L, (buff)->buffer, (buff)->buffsize, size, char), \
+	(buff)->buffsize = size)
+
+#define luaZ_freebuffer(L, buff)	luaZ_resizebuffer(L, buff, 0)
+
+
+LUAI_FUNC char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n);
+LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
+                                        void *data);
+LUAI_FUNC size_t luaZ_read (ZIO* z, void* b, size_t n);	/* read next n bytes */
+LUAI_FUNC int luaZ_lookahead (ZIO *z);
+
+
+
+/* --------- Private Part ------------------ */
+
+struct Zio {
+  size_t n;			/* bytes still unread */
+  const char *p;		/* current position in buffer */
+  lua_Reader reader;
+  void* data;			/* additional data */
+  lua_State *L;			/* Lua state (for reader) */
+};
+
+
+LUAI_FUNC int luaZ_fill (ZIO *z);
+
+#endif
diff --git a/third_party/lua-src/src/lib.rs b/third_party/lua-src/src/lib.rs
new file mode 100644
index 00000000..9bc54484
--- /dev/null
+++ b/third_party/lua-src/src/lib.rs
@@ -0,0 +1,331 @@
+use std::env;
+use std::error::Error;
+use std::fs;
+use std::path::{Path, PathBuf};
+
+/// Represents the version of Lua to build.
+#[derive(Debug, PartialEq, Eq)]
+pub enum Version {
+    Lua51,
+}
+pub use self::Version::*;
+
+/// Represents the configuration for building Lua artifacts.
+pub struct Build {
+    out_dir: Option<PathBuf>,
+    target: Option<String>,
+    host: Option<String>,
+    opt_level: Option<String>,
+    debug: Option<bool>,
+}
+
+/// Represents the artifacts produced by the build process.
+#[derive(Clone, Debug)]
+pub struct Artifacts {
+    include_dir: PathBuf,
+    lib_dir: PathBuf,
+    libs: Vec<String>,
+}
+
+impl Default for Build {
+    fn default() -> Build {
+        Build {
+            out_dir: env::var_os("OUT_DIR").map(PathBuf::from),
+            target: env::var("TARGET").ok(),
+            host: None,
+            opt_level: None,
+            debug: None,
+        }
+    }
+}
+
+impl Build {
+    /// Creates a new `Build` instance with default settings.
+    pub fn new() -> Build {
+        Build::default()
+    }
+
+    /// Sets the output directory for the build artifacts.
+    ///
+    /// This is required if called outside of a build script.
+    pub fn out_dir<P: AsRef<Path>>(&mut self, path: P) -> &mut Build {
+        self.out_dir = Some(path.as_ref().to_path_buf());
+        self
+    }
+
+    /// Sets the target architecture for the build.
+    ///
+    /// This is required if called outside of a build script.
+    pub fn target(&mut self, target: &str) -> &mut Build {
+        self.target = Some(target.to_string());
+        self
+    }
+
+    /// Sets the host architecture for the build.
+    ///
+    /// This is optional and will default to the environment variable `HOST` if not set.
+    /// If called outside of a build script, it will default to the target architecture.
+    pub fn host(&mut self, host: &str) -> &mut Build {
+        self.host = Some(host.to_string());
+        self
+    }
+
+    /// Sets the optimization level for the build.
+    ///
+    /// This is optional and will default to the environment variable `OPT_LEVEL` if not set.
+    /// If called outside of a build script, it will default to `0` in debug mode and `2` otherwise.
+    pub fn opt_level(&mut self, opt_level: &str) -> &mut Build {
+        self.opt_level = Some(opt_level.to_string());
+        self
+    }
+
+    /// Sets whether to build in debug mode.
+    ///
+    /// This is optional and will default to the value of `cfg!(debug_assertions)`.
+    /// If set to `true`, it also enables Lua API checks.
+    pub fn debug(&mut self, debug: bool) -> &mut Build {
+        self.debug = Some(debug);
+        self
+    }
+
+    /// Builds the Lua artifacts for the specified version.
+    pub fn build(&self, version: Version) -> Artifacts {
+        match self.try_build(version) {
+            Ok(artifacts) => artifacts,
+            Err(err) => panic!("{err}"),
+        }
+    }
+
+    /// Attempts to build the Lua artifacts for the specified version.
+    ///
+    /// Returns an error if the build fails.
+    pub fn try_build(&self, version: Version) -> Result<Artifacts, Box<dyn Error>> {
+        let target = self.target.as_ref().ok_or("TARGET is not set")?;
+        let out_dir = self.out_dir.as_ref().ok_or("OUT_DIR is not set")?;
+        let manifest_dir = Path::new(env!("CARGO_MANIFEST_DIR"));
+        let mut source_dir = manifest_dir.join(version.source_dir());
+        let lib_dir = out_dir.join("lib");
+        let include_dir = out_dir.join("include");
+
+        if !include_dir.exists() {
+            fs::create_dir_all(&include_dir)
+                .context(|| format!("Cannot create '{}'", include_dir.display()))?;
+        }
+
+        let mut config = cc::Build::new();
+        config.warnings(false).cargo_metadata(false).target(target);
+
+        match &self.host {
+            Some(host) => {
+                config.host(host);
+            }
+            // Host will be taken from the environment variable
+            None if env::var("HOST").is_ok() => {}
+            None => {
+                // If called outside of build script, set default host
+                config.host(target);
+            }
+        }
+
+        let mut libs = vec![version.lib_name().to_string()];
+        match target {
+            _ if target.contains("linux") => {
+                config.define("LUA_USE_LINUX", None);
+            }
+            _ if target.ends_with("bsd") => {
+                config.define("LUA_USE_LINUX", None);
+            }
+            _ if target.contains("apple-darwin") => {
+                config.define("LUA_USE_LINUX", None);
+            }
+            _ if target.contains("apple-ios") => {
+                config.define("LUA_USE_POSIX", None);
+            }
+            _ if target.contains("windows") => {
+                // Defined in Lua >= 5.3
+                config.define("LUA_USE_WINDOWS", None);
+            }
+            _ if target.ends_with("emscripten") => {
+                config
+                    .define("LUA_USE_POSIX", None)
+                    .cpp(true)
+                    .flag("-fexceptions"); // Enable exceptions to be caught
+
+                let cpp_source_dir = out_dir.join("cpp_source");
+                if cpp_source_dir.exists() {
+                    fs::remove_dir_all(&cpp_source_dir)
+                        .context(|| format!("Cannot remove '{}'", cpp_source_dir.display()))?;
+                }
+                fs::create_dir_all(&cpp_source_dir)
+                    .context(|| format!("Cannot create '{}'", cpp_source_dir.display()))?;
+
+                for file in fs::read_dir(&source_dir)
+                    .context(|| format!("Cannot read '{}'", source_dir.display()))?
+                {
+                    let file = file?;
+                    let filename = file.file_name();
+                    let filename = &*filename.to_string_lossy();
+                    let src_file = source_dir.join(file.file_name());
+                    let dst_file = cpp_source_dir.join(file.file_name());
+
+                    let mut content = fs::read(&src_file)
+                        .context(|| format!("Cannot read '{}'", src_file.display()))?;
+                    if ["lauxlib.h", "lua.h", "lualib.h"].contains(&filename) {
+                        content.splice(0..0, b"extern \"C\" {\n".to_vec());
+                        content.extend(b"\n}".to_vec())
+                    }
+                    fs::write(&dst_file, content)
+                        .context(|| format!("Cannot write to '{}'", dst_file.display()))?;
+                }
+                source_dir = cpp_source_dir
+            }
+            _ if target.contains("wasi") => {
+                // WASI is posix-like, but further patches are needed to the Lua
+                // source to get it compiling.
+                config.define("LUA_USE_POSIX", None);
+
+                // Bring in just enough signal-handling support to get Lua at
+                // least compiling, but WASI in general does not support
+                // signals.
+                config.define("_WASI_EMULATED_SIGNAL", None);
+                libs.push("wasi-emulated-signal".to_string());
+
+                // https://github.com/WebAssembly/wasi-sdk/blob/main/SetjmpLongjmp.md
+                // for information about getting setjmp/longjmp working.
+                config.flag("-mllvm").flag("-wasm-enable-eh");
+                config.flag("-mllvm").flag("-wasm-use-legacy-eh=false");
+                config.flag("-mllvm").flag("-wasm-enable-sjlj");
+                libs.push("setjmp".to_string());
+            }
+            _ => Err(format!("don't know how to build Lua for {target}"))?,
+        }
+
+        let debug = self.debug.unwrap_or(cfg!(debug_assertions));
+        if debug {
+            config.define("LUA_USE_APICHECK", None);
+            config.debug(true);
+        }
+
+        match &self.opt_level {
+            Some(opt_level) => {
+                config.opt_level_str(opt_level);
+            }
+            // Opt level will be taken from the environment variable
+            None if env::var("OPT_LEVEL").is_ok() => {}
+            None => {
+                // If called outside of build script, set default opt level
+                config.opt_level(if debug { 0 } else { 2 });
+            }
+        }
+
+        config
+            .include(&source_dir)
+            .warnings(false) // Suppress all warnings
+            .flag_if_supported("-fno-common") // Compile common globals like normal definitions
+            .add_files_by_ext(&source_dir, "c")?
+            .out_dir(&lib_dir)
+            .try_compile(version.lib_name())?;
+
+        for f in &["lauxlib.h", "lua.h", "luaconf.h", "lualib.h"] {
+            let from = source_dir.join(f);
+            let to = include_dir.join(f);
+            fs::copy(&from, &to)
+                .context(|| format!("Cannot copy '{}' to '{}'", from.display(), to.display()))?;
+        }
+
+        Ok(Artifacts {
+            include_dir,
+            lib_dir,
+            libs,
+        })
+    }
+}
+
+impl Version {
+    fn source_dir(&self) -> &'static str {
+        match self {
+            Lua51 => "lua-5.1.5",
+        }
+    }
+
+    fn lib_name(&self) -> &'static str {
+        match self {
+            Lua51 => "lua5.1",
+        }
+    }
+}
+
+impl Artifacts {
+    /// Returns the directory containing the Lua headers.
+    pub fn include_dir(&self) -> &Path {
+        &self.include_dir
+    }
+
+    /// Returns the directory containing the Lua libraries.
+    pub fn lib_dir(&self) -> &Path {
+        &self.lib_dir
+    }
+
+    /// Returns the names of the Lua libraries built.
+    pub fn libs(&self) -> &[String] {
+        &self.libs
+    }
+
+    /// Prints the necessary Cargo metadata for linking the Lua libraries.
+    ///
+    /// This method is typically called in a build script to inform Cargo
+    /// about the location of the Lua libraries and how to link them.
+    pub fn print_cargo_metadata(&self) {
+        println!("cargo:rustc-link-search=native={}", self.lib_dir.display());
+        for lib in self.libs.iter() {
+            println!("cargo:rustc-link-lib=static:-bundle={lib}");
+        }
+    }
+}
+
+trait ErrorContext<T> {
+    fn context(self, f: impl FnOnce() -> String) -> Result<T, Box<dyn Error>>;
+}
+
+impl<T, E: Error> ErrorContext<T> for Result<T, E> {
+    fn context(self, f: impl FnOnce() -> String) -> Result<T, Box<dyn Error>> {
+        self.map_err(|e| format!("{}: {e}", f()).into())
+    }
+}
+
+trait AddFilesByExt {
+    fn add_files_by_ext(&mut self, dir: &Path, ext: &str) -> Result<&mut Self, Box<dyn Error>>;
+}
+
+impl AddFilesByExt for cc::Build {
+    fn add_files_by_ext(&mut self, dir: &Path, ext: &str) -> Result<&mut Self, Box<dyn Error>> {
+        for entry in fs::read_dir(dir)
+            .context(|| format!("Cannot read '{}'", dir.display()))?
+            .filter_map(|e| e.ok())
+            .filter(|e| e.path().extension() == Some(ext.as_ref()))
+        {
+            self.file(entry.path());
+        }
+        // BENILLA ADDITION. Upstream emits no `rerun-if-changed` for the Lua sources, which is
+        // harmless when they are an immutable registry copy and a genuine trap once they are a
+        // patched fork: editing `lvm.c` then rebuilds NOTHING, the old object file is relinked, and
+        // the change appears not to work. That cost real time on the very first patch here — six
+        // tests failed against a stale VM and the obvious conclusion was that the patch was wrong.
+        // `Build::build` runs inside mlua-sys's build script, so anything printed here is that
+        // script's output and cargo honours it.
+        //
+        // **Emitted for EVERY file in the directory, not just the ones being compiled.** The first
+        // version of this tracked only the `ext` matches — i.e. `.c` — and the identical trap came
+        // straight back one file-type over: flipping `LUA_COMPAT_LSTR` in `luaconf.h` rebuilt
+        // nothing and the new test failed against a stale object file, exactly as before. A header
+        // is an input to every translation unit here; so is anything else that lands in this
+        // directory, which is why this no longer filters.
+        for entry in fs::read_dir(dir)
+            .context(|| format!("Cannot read '{}'", dir.display()))?
+            .filter_map(|e| e.ok())
+        {
+            println!("cargo:rerun-if-changed={}", entry.path().display());
+        }
+        Ok(self)
+    }
+}