com32/lua/src/lundump.c

   1 /*
   2 ** $Id: lundump.c,v 2.7.1.4 2008/04/04 19:51:41 roberto Exp $
   3 ** load precompiled Lua chunks
   4 ** See Copyright Notice in lua.h
   5 */
   6
   7 #include <string.h>
   8
   9 #define lundump_c
  10 #define LUA_CORE
  11
  12 #include "lua.h"
  13
  14 #include "ldebug.h"
  15 #include "ldo.h"
  16 #include "lfunc.h"
  17 #include "lmem.h"
  18 #include "lobject.h"
  19 #include "lstring.h"
  20 #include "lundump.h"
  21 #include "lzio.h"
  22
  23 typedef struct {
  24  lua_State* L;
  25  ZIO* Z;
  26  Mbuffer* b;
  27  const char* name;
  28 } LoadState;
  29
  30 #ifdef LUAC_TRUST_BINARIES
  31 #define IF(c,s)
  32 #define error(S,s)
  33 #else
  34 #define IF(c,s)         if (c) error(S,s)
  35
  36 static void error(LoadState* S, const char* why)
  37 {
  38  luaO_pushfstring(S->L,"%s: %s in precompiled chunk",S->name,why);
  39  luaD_throw(S->L,LUA_ERRSYNTAX);
  40 }
  41 #endif
  42
  43 #define LoadMem(S,b,n,size)     LoadBlock(S,b,(n)*(size))
  44 #define LoadByte(S)             (lu_byte)LoadChar(S)
  45 #define LoadVar(S,x)            LoadMem(S,&x,1,sizeof(x))
  46 #define LoadVector(S,b,n,size)  LoadMem(S,b,n,size)
  47
  48 static void LoadBlock(LoadState* S, void* b, size_t size)
  49 {
  50  size_t r=luaZ_read(S->Z,b,size);
  51  IF (r!=0, "unexpected end");
  52 }
  53
  54 static int LoadChar(LoadState* S)
  55 {
  56  char x;
  57  LoadVar(S,x);
  58  return x;
  59 }
  60
  61 static int LoadInt(LoadState* S)
  62 {
  63  int x;
  64  LoadVar(S,x);
  65  IF (x<0, "bad integer");
  66  return x;
  67 }
  68
  69 static lua_Number LoadNumber(LoadState* S)
  70 {
  71  lua_Number x;
  72  LoadVar(S,x);
  73  return x;
  74 }
  75
  76 static TString* LoadString(LoadState* S)
  77 {
  78  size_t size;
  79  LoadVar(S,size);
  80  if (size==0)
  81   return NULL;
  82  else
  83  {
  84   char* s=luaZ_openspace(S->L,S->b,size);
  85   LoadBlock(S,s,size);
  86   return luaS_newlstr(S->L,s,size-1);           /* remove trailing '\0' */
  87  }
  88 }
  89
  90 static void LoadCode(LoadState* S, Proto* f)
  91 {
  92  int n=LoadInt(S);
  93  f->code=luaM_newvector(S->L,n,Instruction);
  94  f->sizecode=n;
  95  LoadVector(S,f->code,n,sizeof(Instruction));
  96 }
  97
  98 static Proto* LoadFunction(LoadState* S, TString* p);
  99
 100 static void LoadConstants(LoadState* S, Proto* f)
 101 {
 102  int i,n;
 103  n=LoadInt(S);
 104  f->k=luaM_newvector(S->L,n,TValue);
 105  f->sizek=n;
 106  for (i=0; i<n; i++) setnilvalue(&f->k[i]);
 107  for (i=0; i<n; i++)
 108  {
 109   TValue* o=&f->k[i];
 110   int t=LoadChar(S);
 111   switch (t)
 112   {
 113    case LUA_TNIL:
 114         setnilvalue(o);
 115         break;
 116    case LUA_TBOOLEAN:
 117         setbvalue(o,LoadChar(S)!=0);
 118         break;
 119    case LUA_TNUMBER:
 120         setnvalue(o,LoadNumber(S));
 121         break;
 122    case LUA_TSTRING:
 123         setsvalue2n(S->L,o,LoadString(S));
 124         break;
 125    default:
 126         error(S,"bad constant");
 127         break;
 128   }
 129  }
 130  n=LoadInt(S);
 131  f->p=luaM_newvector(S->L,n,Proto*);
 132  f->sizep=n;
 133  for (i=0; i<n; i++) f->p[i]=NULL;
 134  for (i=0; i<n; i++) f->p[i]=LoadFunction(S,f->source);
 135 }
 136
 137 static void LoadDebug(LoadState* S, Proto* f)
 138 {
 139  int i,n;
 140  n=LoadInt(S);
 141  f->lineinfo=luaM_newvector(S->L,n,int);
 142  f->sizelineinfo=n;
 143  LoadVector(S,f->lineinfo,n,sizeof(int));
 144  n=LoadInt(S);
 145  f->locvars=luaM_newvector(S->L,n,LocVar);
 146  f->sizelocvars=n;
 147  for (i=0; i<n; i++) f->locvars[i].varname=NULL;
 148  for (i=0; i<n; i++)
 149  {
 150   f->locvars[i].varname=LoadString(S);
 151   f->locvars[i].startpc=LoadInt(S);
 152   f->locvars[i].endpc=LoadInt(S);
 153  }
 154  n=LoadInt(S);
 155  f->upvalues=luaM_newvector(S->L,n,TString*);
 156  f->sizeupvalues=n;
 157  for (i=0; i<n; i++) f->upvalues[i]=NULL;
 158  for (i=0; i<n; i++) f->upvalues[i]=LoadString(S);
 159 }
 160
 161 static Proto* LoadFunction(LoadState* S, TString* p)
 162 {
 163  Proto* f;
 164  if (++S->L->nCcalls > LUAI_MAXCCALLS) error(S,"code too deep");
 165  f=luaF_newproto(S->L);
 166  setptvalue2s(S->L,S->L->top,f); incr_top(S->L);
 167  f->source=LoadString(S); if (f->source==NULL) f->source=p;
 168  f->linedefined=LoadInt(S);
 169  f->lastlinedefined=LoadInt(S);
 170  f->nups=LoadByte(S);
 171  f->numparams=LoadByte(S);
 172  f->is_vararg=LoadByte(S);
 173  f->maxstacksize=LoadByte(S);
 174  LoadCode(S,f);
 175  LoadConstants(S,f);
 176  LoadDebug(S,f);
 177  IF (!luaG_checkcode(f), "bad code");
 178  S->L->top--;
 179  S->L->nCcalls--;
 180  return f;
 181 }
 182
 183 static void LoadHeader(LoadState* S)
 184 {
 185  char h[LUAC_HEADERSIZE];
 186  char s[LUAC_HEADERSIZE];
 187  luaU_header(h);
 188  LoadBlock(S,s,LUAC_HEADERSIZE);
 189  IF (memcmp(h,s,LUAC_HEADERSIZE)!=0, "bad header");
 190 }
 191
 192 /*
 193 ** load precompiled chunk
 194 */
 195 Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name)
 196 {
 197  LoadState S;
 198  if (*name=='@' || *name=='=')
 199   S.name=name+1;
 200  else if (*name==LUA_SIGNATURE[0])
 201   S.name="binary string";
 202  else
 203   S.name=name;
 204  S.L=L;
 205  S.Z=Z;
 206  S.b=buff;
 207  LoadHeader(&S);
 208  return LoadFunction(&S,luaS_newliteral(L,"=?"));
 209 }
 210
 211 /*
 212 * make header
 213 */
 214 void luaU_header (char* h)
 215 {
 216  int x=1;
 217  memcpy(h,LUA_SIGNATURE,sizeof(LUA_SIGNATURE)-1);
 218  h+=sizeof(LUA_SIGNATURE)-1;
 219  *h++=(char)LUAC_VERSION;
 220  *h++=(char)LUAC_FORMAT;
 221  *h++=(char)*(char*)&x;                         /* endianness */
 222  *h++=(char)sizeof(int);
 223  *h++=(char)sizeof(size_t);
 224  *h++=(char)sizeof(Instruction);
 225  *h++=(char)sizeof(lua_Number);
 226  *h++=(char)(((lua_Number)0.5)==0);             /* is lua_Number integral? */
 227 }