changes by lhf (better control of chars x bytes)

1 files changed, 41 insertions, 21 deletions

diff --git a/lundump.c b/lundump.c
index 170c9ece..ba1a3dc3 100644
--- a/lundump.c
+++ b/lundump.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lundump.c,v 2.15 2011/02/07 19:15:24 roberto Exp roberto $
+** $Id: lundump.c,v 1.69 2011/05/06 13:35:17 lhf Exp $
 ** load precompiled Lua chunks
 ** See Copyright Notice in lua.h
 */
@@ -38,6 +38,10 @@ static void error(LoadState* S, const char* why)
 #define LoadVar(S,x)            LoadMem(S,&x,1,sizeof(x))
 #define LoadVector(S,b,n,size)  LoadMem(S,b,n,size)
 
+#if !defined(luai_verifycode)
+#define luai_verifycode(L,b,f)  (f)
+#endif
+
 static void LoadBlock(LoadState* S, void* b, size_t size)
 {
  if (luaZ_read(S->Z,b,size)!=0) error(S,"corrupted");
@@ -54,6 +58,7 @@ static int LoadInt(LoadState* S)
 {
  int x;
  LoadVar(S,x);
+ if (x<0) error(S,"corrupted");
  return x;
 }
 
@@ -73,7 +78,7 @@ static TString* LoadString(LoadState* S)
  else
  {
   char* s=luaZ_openspace(S->L,S->b,size);
-  LoadBlock(S,s,size);
+  LoadBlock(S,s,size*sizeof(char));
   return luaS_newlstr(S->L,s,size-1);           /* remove trailing '\0' */
  }
 }
@@ -175,13 +180,23 @@ static Proto* LoadFunction(LoadState* S)
  return f;
 }
 
+/* the code below must be consistent with the code in luaU_header */
+#define N0      LUAC_HEADERSIZE
+#define N1      (sizeof(LUA_SIGNATURE)-sizeof(char))
+#define N2      N1+2
+#define N3      N2+6
+
 static void LoadHeader(LoadState* S)
 {
- char h[LUAC_HEADERSIZE];
- char s[LUAC_HEADERSIZE];
+ lu_byte h[LUAC_HEADERSIZE];
+ lu_byte s[LUAC_HEADERSIZE];
  luaU_header(h);
- LoadBlock(S,s,LUAC_HEADERSIZE-1);  /* 1st char already read */
- if (memcmp(h+1,s,LUAC_HEADERSIZE-1)!=0) error(S,"incompatible");
+ memcpy(s,h,sizeof(char));                      /* first char already read */
+ LoadBlock(S,s+sizeof(char),LUAC_HEADERSIZE-sizeof(char));
+ if (memcmp(h,s,N0)==0) return;
+ if (memcmp(h,s,N1)!=0) error(S,"not a");
+ if (memcmp(h,s,N2)!=0) error(S,"version mismatch in");
+ if (memcmp(h,s,N3)!=0) error(S,"incompatible"); else error(S,"corrupted");
 }
 
 /*
@@ -200,25 +215,30 @@ Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name)
  S.Z=Z;
  S.b=buff;
  LoadHeader(&S);
- return LoadFunction(&S);
+ return luai_verifycode(L,buff,LoadFunction(&S));
 }
 
+#define MYINT(s)        (s[0]-'0')
+#define VERSION         MYINT(LUA_VERSION_MAJOR)*16+MYINT(LUA_VERSION_MINOR)
+#define FORMAT          0               /* this is the official format */
+
 /*
-* make header
-* if you make any changes in the header or in LUA_SIGNATURE,
-* be sure to update LUAC_HEADERSIZE accordingly in lundump.h.
+* make header for precompiled chunks
+* if you change the code below be sure to update LoadHeader and FORMAT above
+* and LUAC_HEADERSIZE in lundump.h
 */
-void luaU_header (char* h)
+void luaU_header (lu_byte* h)
 {
  int x=1;
- memcpy(h,LUA_SIGNATURE,(sizeof(LUA_SIGNATURE)-1)*sizeof(char));
- h+=(sizeof(LUA_SIGNATURE)-1)*sizeof(char);
- *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? */
+ memcpy(h,LUA_SIGNATURE,sizeof(LUA_SIGNATURE)-sizeof(char));
+ h+=sizeof(LUA_SIGNATURE)-sizeof(char);
+ *h++=cast_byte(VERSION);
+ *h++=cast_byte(FORMAT);
+ *h++=cast_byte(*(char*)&x);                    /* endianness */
+ *h++=cast_byte(sizeof(int));
+ *h++=cast_byte(sizeof(size_t));
+ *h++=cast_byte(sizeof(Instruction));
+ *h++=cast_byte(sizeof(lua_Number));
+ *h++=cast_byte(((lua_Number)0.5)==0);          /* is lua_Number integral? */
+ memcpy(h,LUAC_TAIL,sizeof(LUAC_TAIL)-sizeof(char));
 }