1 files changed, 272 insertions, 0 deletions

diff --git a/lundump.c b/lundump.c
new file mode 100644
index 00000000..32d7359a
--- /dev/null
+++ b/lundump.c
@@ -0,0 +1,272 @@
+/*
+** $Id: lundump.c,v 1.4 1998/01/13 20:05:24 lhf Exp $
+** load bytecodes from files
+** See Copyright Notice in lua.h
+*/
+
+#include <stdio.h>
+#include "lauxlib.h"
+#include "lfunc.h"
+#include "lmem.h"
+#include "lstring.h"
+#include "lundump.h"
+
+typedef struct {
+ ZIO* Z;
+ int SwapNumber;
+ int LoadFloat;
+} Sundump;
+
+static void unexpectedEOZ(ZIO* Z)
+{
+ luaL_verror("unexpected end of binary file %s",Z->name);
+}
+
+static int ezgetc(ZIO* Z)
+{
+ int c=zgetc(Z);
+ if (c==EOZ) unexpectedEOZ(Z);
+ return c;
+}
+
+static int ezread(ZIO* Z, void* b, int n)
+{
+ int r=zread(Z,b,n);
+ if (r!=0) unexpectedEOZ(Z);
+ return r;
+}
+
+static int LoadWord(ZIO* Z)
+{
+ int hi=ezgetc(Z);
+ int lo=ezgetc(Z);
+ return (hi<<8)|lo;
+}
+
+static void* LoadBlock(int size, ZIO* Z)
+{
+ void* b=luaM_malloc(size);
+ ezread(Z,b,size);
+ return b;
+}
+
+static int LoadSize(ZIO* Z)
+{
+ int hi=LoadWord(Z);
+ int lo=LoadWord(Z);
+ int s=(hi<<16)|lo;
+ if (hi!=0 && s==lo)
+  luaL_verror("code too long (%ld bytes)",(hi<<16)|(long)lo);
+ return s;
+}
+
+static char* LoadString(ZIO* Z)
+{
+ int size=LoadWord(Z);
+ if (size==0)
+  return NULL;
+ else
+ {
+  char* b=luaL_openspace(size);
+  ezread(Z,b,size);
+  return b;
+ }
+}
+
+static TaggedString* LoadTString(ZIO* Z)
+{
+ char* s=LoadString(Z);
+ return (s==NULL) ? NULL : luaS_new(s);
+}
+
+static void SwapFloat(float* f)
+{
+ Byte* p=(Byte*)f;
+ Byte* q=p+sizeof(float)-1;
+ Byte t;
+ t=*p; *p++=*q; *q--=t;
+ t=*p; *p++=*q; *q--=t;
+}
+
+static void SwapDouble(double* f)
+{
+ Byte* p=(Byte*)f;
+ Byte* q=p+sizeof(double)-1;
+ Byte t;
+ t=*p; *p++=*q; *q--=t;
+ t=*p; *p++=*q; *q--=t;
+ t=*p; *p++=*q; *q--=t;
+ t=*p; *p++=*q; *q--=t;
+}
+
+static real LoadNumber(Sundump* S)
+{
+ if (S->LoadFloat)
+ {
+  float f;
+  ezread(S->Z,&f,sizeof(f));
+  if (S->SwapNumber) SwapFloat(&f);
+  return f;
+ }
+ else
+ {
+  double f;
+  ezread(S->Z,&f,sizeof(f));
+  if (S->SwapNumber) SwapDouble(&f);
+  return f;
+ }
+}
+
+static void LoadLocals(TProtoFunc* tf, ZIO* Z)
+{
+ int i,n=LoadWord(Z);
+ if (n==0) return;
+ tf->locvars=luaM_newvector(n+1,LocVar);
+ for (i=0; i<n; i++)
+ {
+  tf->locvars[i].line=LoadWord(Z);
+  tf->locvars[i].varname=LoadTString(Z);
+ }
+ tf->locvars[i].line=-1;                /* flag end of vector */
+ tf->locvars[i].varname=NULL;
+}
+
+static void LoadConstants(TProtoFunc* tf, Sundump* S)
+{
+ int i,n=LoadWord(S->Z);
+ tf->nconsts=n;
+ if (n==0) return;
+ tf->consts=luaM_newvector(n,TObject);
+ for (i=0; i<n; i++)
+ {
+  TObject* o=tf->consts+i;
+  int c=ezgetc(S->Z);
+  switch (c)
+  {
+   case ID_NUM:
+        ttype(o)=LUA_T_NUMBER;
+        nvalue(o)=LoadNumber(S);
+        break;
+   case ID_STR:
+        ttype(o)=LUA_T_STRING;  
+        tsvalue(o)=LoadTString(S->Z);
+        break;
+   case ID_FUN:
+        ttype(o)=LUA_T_PROTO;
+        tfvalue(o)=NULL;
+        break;
+#ifdef DEBUG
+   default:                             /* cannot happen */
+        luaL_verror("internal error in LoadConstants: "
+                "bad constant #%d type=%d ('%c')\n",i,c,c);
+        break;
+#endif
+  }
+ }
+}
+
+static TProtoFunc* LoadFunction(Sundump* S);
+
+static void LoadFunctions(TProtoFunc* tf, Sundump* S)
+{
+ while (zgetc(S->Z)==ID_FUNCTION)
+ {
+  int i=LoadWord(S->Z); 
+  TProtoFunc* t=LoadFunction(S);
+  TObject* o=tf->consts+i;
+  tfvalue(o)=t;
+ }
+}
+
+static TProtoFunc* LoadFunction(Sundump* S)
+{
+ ZIO* Z=S->Z;
+ TProtoFunc* tf=luaF_newproto();
+ tf->lineDefined=LoadWord(Z);
+ tf->fileName=LoadTString(Z);
+ tf->code=LoadBlock(LoadSize(Z),Z);
+ LoadConstants(tf,S);
+ LoadLocals(tf,Z);
+ LoadFunctions(tf,S);
+ return tf;
+}
+
+static void LoadSignature(ZIO* Z)
+{
+ char* s=SIGNATURE;
+ while (*s!=0 && ezgetc(Z)==*s)
+  ++s;
+ if (*s!=0) luaL_verror("bad signature in binary file %s",Z->name);
+}
+
+static void LoadHeader(Sundump* S)
+{
+ ZIO* Z=S->Z;
+ int version,sizeofR;
+ LoadSignature(Z);
+ version=ezgetc(Z);
+ if (version>VERSION)
+  luaL_verror(
+        "binary file %s too new: version=0x%02x; expected at most 0x%02x",
+        Z->name,version,VERSION);
+ if (version<0x31)                      /* major change in 3.1 */
+  luaL_verror(
+        "binary file %s too old: version=0x%02x; expected at least 0x%02x",
+        Z->name,version,0x31);
+ sizeofR=ezgetc(Z);                     /* test float representation */
+ if (sizeofR==sizeof(float))
+ {
+  float f,tf=TEST_FLOAT;
+  ezread(Z,&f,sizeof(f));
+  if (f!=tf)
+  {
+   SwapFloat(&f);
+   if (f!=tf)
+    luaL_verror("unknown float representation in binary file %s",Z->name);
+   S->SwapNumber=1;
+  }
+  S->LoadFloat=1;
+ }
+ else if (sizeofR==sizeof(double))
+ {
+  double f,tf=TEST_FLOAT;
+  ezread(Z,&f,sizeof(f));
+  if (f!=tf)
+  {
+   SwapDouble(&f);
+   if (f!=tf)
+    luaL_verror("unknown float representation in binary file %s",Z->name);
+   S->SwapNumber=1;
+  }
+  S->LoadFloat=0;
+ }
+ else
+  luaL_verror(
+       "floats in binary file %s have %d bytes; "
+       "expected %d (float) or %d (double)",
+       Z->name,sizeofR,sizeof(float),sizeof(double));
+}
+
+static TProtoFunc* LoadChunk(Sundump* S)
+{
+ LoadHeader(S);
+ return LoadFunction(S);
+}
+
+/*
+** load one chunk from a file or buffer
+** return main if ok and NULL at EOF
+*/
+TProtoFunc* luaU_undump1(ZIO* Z)
+{
+ int c=zgetc(Z);
+ Sundump S;
+ S.Z=Z;
+ S.SwapNumber=0;
+ S.LoadFloat=1;
+ if (c==ID_CHUNK)
+  return LoadChunk(&S);
+ else if (c!=EOZ)
+  luaL_verror("%s is not a lua binary file",Z->name);
+ return NULL;
+}