readHeader

5 files changed, 128 insertions, 40 deletions

diff --git a/src/lfunc.js b/src/lfunc.js
new file mode 100644
index 0000000..faa0887
--- /dev/null
+++ b/src/lfunc.js
@@ -0,0 +1,27 @@
+/*jshint esversion: 6 */
+"use strict";
+
+class Proto {
+
+    constructor(L) {
+        this.k = [];              // constants used by the function
+        this.p = [];              // functions defined inside the function
+        this.code = [];           // opcodes
+        this.cache = null;        // last-created closure with this prototype
+        this.lineinfo = [];       // map from opcodes to source lines (debug information)
+        this.upvalues = [];       // upvalue information
+        this.numparams = 0;       // number of fixed parameters
+        this.is_vararg = 0;
+        this.maxstacksize = 0;    // number of registers needed by this function
+        this.locvars = [];        // information about local variables (debug information)
+        this.linedefined = 0;     // debug information
+        this.lastlinedefined = 0; // debug information
+        this.source = null;       // used for debug information
+    }
+
+}
+
+
+module.exports = {
+    Proto: Proto
+};
\ No newline at end of file
diff --git a/src/lobject.js b/src/lobject.js
index 2e21f16..1858fd3 100644
--- a/src/lobject.js
+++ b/src/lobject.js
@@ -4,7 +4,7 @@
 class LClosure {
 
     constructor(L, n) {
-        this.p = [];
+        this.p = null;
         this.nupvalues = n;
     }
 
diff --git a/src/lstate.js b/src/lstate.js
index b0002c3..979b89c 100644
--- a/src/lstate.js
+++ b/src/lstate.js
@@ -1,32 +1,24 @@
 /*jshint esversion: 6 */
 "use strict";
 
+const thread_status = require('./lua.js').thread_status;
+
 class lua_State {
 
     constructor() {
-        // CommonHeader;
-        // unsigned short nci;  /* number of items in 'ci' list */
-        // lu_byte status;
-        // StkId top;  /* first free slot in the stack */
-        // global_State *l_G;
-        // CallInfo *ci;  /* call info for current function */
-        // const Instruction *oldpc;  /* last pc traced */
-        // StkId stack_last;  /* last free slot in the stack */
-        // StkId stack;  /* stack base */
-        // UpVal *openupval;  /* list of open upvalues in this stack */
-        // GCObject *gclist;
-        // struct lua_State *twups;   list of threads with open upvalues 
-        // struct lua_longjmp *errorJmp;  /* current error recover point */
-        // CallInfo base_ci;  /* CallInfo for first level (C calling Lua) */
-        // volatile lua_Hook hook;
-        // ptrdiff_t errfunc;  /* current error handling function (stack index) */
-        // int stacksize;
-        // int basehookcount;
-        // int hookcount;
-        // unsigned short nny;  /* number of non-yieldable calls in stack */
-        // unsigned short nCcalls;  /* number of nested C calls */
-        // l_signalT hookmask;
-        // lu_byte allowhook;
+        this.next = null;
+        this.stack = null;
+        this.ci = null;
+        this.nci = 0;
+        this.stacksize = 0;
+        this.twups = [this];
+        this.errorJmp = null;
+        this.hook = null;
+        this.allowhook = true;
+        this.openupval = null;
+        this.nny = 1;
+        this.status = thread_status.LUA_OK;
+        this.errfunc = 0;
     }
 
 }
diff --git a/src/lua.js b/src/lua.js
new file mode 100644
index 0000000..f41991e
--- /dev/null
+++ b/src/lua.js
@@ -0,0 +1,16 @@
+/*jshint esversion: 6 */
+"use strict";
+
+const thread_status = {
+    LUA_OK:        0,
+    LUA_YIELD:     1,
+    LUA_ERRRUN:    2,
+    LUA_ERRSYNTAX: 3,
+    LUA_ERRMEM:    4,
+    LUA_ERRGCMM:   5,
+    LUA_ERRERR:    6
+};
+
+module.exports = {
+    thread_status: thread_status
+};
\ No newline at end of file
diff --git a/src/lundump.js b/src/lundump.js
index 69445d4..1d1a959 100644
--- a/src/lundump.js
+++ b/src/lundump.js
@@ -3,8 +3,11 @@
 
 const DataView  = require('buffer-dataview');
 const fs        = require('fs');
+const assert    = require('assert');
+
 const lua_State = require('./lstate.js').lua_State;
 const LClosure  = require('./lobject.js').LClosure;
+const Proto     = require('./lfunc.js').Proto;
 
 /**
  * Parse Lua 5.3 bytecode
@@ -15,9 +18,17 @@ class BytecodeParser {
     /**
      * Initilialize bytecode parser
      * @constructor
+     * @param {lua_State} Lua state object
      * @param {DataView} dataView Contains the binary data
      */
-    constructor(dataView) {
+    constructor(L, dataView) {
+        this.intSize = 4;
+        this.size_tSize = 8;
+        this.instructionSize = 4;
+        this.integerSize = 8;
+        this.numberSize = 8;
+
+        this.L = L;
         this.dataView = dataView;
         this.offset = 0;
     }
@@ -32,36 +43,78 @@ class BytecodeParser {
         return byte;
     }
 
-    peekWord() {
-        return this.dataView.getUint32(this.offset, true);
+    peekInteger() {
+        return this.dataView.getInt32(this.offset, true);
+    }
+
+    readInteger() {
+        let integer = this.peekInteger();
+        this.offset += this.integerSize;
+
+        return integer;
+    }
+
+    peekNumber() {
+        return this.dataView.getFloat64(this.offset, true);
+    }
+
+    readNumber() {
+        let number = this.peekNumber();
+        this.offset += this.numberSize;
+
+        return number;
     }
 
-    readWord() {
-        let word = this.peekWord();
-        this.offset += 4;
+    readString(n) {
+        let string = "";
 
-        return word;
+        for (let i = 0; i < n; i++)
+            string += String.fromCharCode(this.readByte());
+
+        return string;
     }
 
     checkHeader() {
-        if (this.readByte() !== 0x1b
-            || this.readByte() !== 0x4c
-            || this.readByte() !== 0x75
-            || this.readByte() !== 0x61)
-            throw new Error("Bad LUA_SIGNATURE, expected [1b 4c 75 61]");
+        if (this.readString(4) !== "\x1bLua")
+            throw new Error("bad LUA_SIGNATURE, expected '<esc>Lua'");
 
         if (this.readByte() !== 0x53)
-            throw new Error("Bad Lua version, expected 5.3");
+            throw new Error("bad Lua version, expected 5.3");
 
         if (this.readByte() !== 0)
-            throw new Error("Supports only official PUC-Rio implementation")
+            throw new Error("supports only official PUC-Rio implementation");
+
+        if (this.readString(6) !== "\x19\x93\r\n\x1a\n")
+            throw new Error("bytecode corrupted");
+
+        this.intSize         = this.readByte();
+        this.size_tSize      = this.readByte();
+        this.instructionSize = this.readByte();
+        this.integerSize     = this.readByte();
+        this.numberSize      = this.readByte();
+
+        if (this.readInteger() !== 0x5678)
+            throw new Error("endianness mismatch");
+
+        if (this.readNumber() !== 370.5)
+            throw new Error("float format mismatch in");
+
     }
 
     luaU_undump() {
         checkHeader();
-        let cl = new LClosure(L, this.readByte());
+
+        let cl = new LClosure(this.L, this.readByte());
+        L.top++;
+        cl.p = new Proto(this.L);
+
+        loadFunction(cl.p);
+
+        assert(cl.nupvalues === cl.p.upvalues.length);
 
         return cl;
     }
 
-}
\ No newline at end of file
+}
+
+module.exports = BytecodeParser;
\ No newline at end of file