src/lua/lobject.h

   1 /*
   2 ** $Id: lobject.h,v 2.20.1.2 2008/08/06 13:29:48 roberto Exp $
   3 ** Type definitions for Lua objects
   4 ** See Copyright Notice in lua.h
   5 */
   6
   7
   8 #ifndef lobject_h
   9 #define lobject_h
  10
  11
  12 #include <stdarg.h>
  13
  14
  15 #include "llimits.h"
  16 #include "lua.h"
  17
  18
  19 /* tags for values visible from Lua */
  20 #define LAST_TAG        LUA_TTHREAD
  21
  22 #define NUM_TAGS        (LAST_TAG+1)
  23
  24
  25 /*
  26 ** Extra tags for non-values
  27 */
  28 #define LUA_TPROTO      (LAST_TAG+1)
  29 #define LUA_TUPVAL      (LAST_TAG+2)
  30 #define LUA_TDEADKEY    (LAST_TAG+3)
  31
  32
  33 /*
  34 ** Union of all collectable objects
  35 */
  36 typedef union GCObject GCObject;
  37
  38
  39 /*
  40 ** Common Header for all collectable objects (in macro form, to be
  41 ** included in other objects)
  42 */
  43 #define CommonHeader    GCObject *next; lu_byte tt; lu_byte marked
  44
  45
  46 /*
  47 ** Common header in struct form
  48 */
  49 typedef struct GCheader {
  50   CommonHeader;
  51 } GCheader;
  52
  53
  54
  55
  56 /*
  57 ** Union of all Lua values
  58 */
  59 typedef union {
  60   GCObject *gc;
  61   void *p;
  62   lua_Number n;
  63   int b;
  64 } Value;
  65
  66
  67 /*
  68 ** Tagged Values
  69 */
  70
  71 #define TValuefields    Value value; int tt
  72
  73 typedef struct lua_TValue {
  74   TValuefields;
  75 } TValue;
  76
  77
  78 /* Macros to test type */
  79 #define ttisnil(o)      (ttype(o) == LUA_TNIL)
  80 #define ttisnumber(o)   (ttype(o) == LUA_TNUMBER)
  81 #define ttisstring(o)   (ttype(o) == LUA_TSTRING)
  82 #define ttistable(o)    (ttype(o) == LUA_TTABLE)
  83 #define ttisfunction(o) (ttype(o) == LUA_TFUNCTION)
  84 #define ttisboolean(o)  (ttype(o) == LUA_TBOOLEAN)
  85 #define ttisuserdata(o) (ttype(o) == LUA_TUSERDATA)
  86 #define ttisthread(o)   (ttype(o) == LUA_TTHREAD)
  87 #define ttislightuserdata(o)    (ttype(o) == LUA_TLIGHTUSERDATA)
  88
  89 /* Macros to access values */
  90 #define ttype(o)        ((o)->tt)
  91 #define gcvalue(o)      check_exp(iscollectable(o), (o)->value.gc)
  92 #define pvalue(o)       check_exp(ttislightuserdata(o), (o)->value.p)
  93 #define nvalue(o)       check_exp(ttisnumber(o), (o)->value.n)
  94 #define rawtsvalue(o)   check_exp(ttisstring(o), &(o)->value.gc->ts)
  95 #define tsvalue(o)      (&rawtsvalue(o)->tsv)
  96 #define rawuvalue(o)    check_exp(ttisuserdata(o), &(o)->value.gc->u)
  97 #define uvalue(o)       (&rawuvalue(o)->uv)
  98 #define clvalue(o)      check_exp(ttisfunction(o), &(o)->value.gc->cl)
  99 #define hvalue(o)       check_exp(ttistable(o), &(o)->value.gc->h)
 100 #define bvalue(o)       check_exp(ttisboolean(o), (o)->value.b)
 101 #define thvalue(o)      check_exp(ttisthread(o), &(o)->value.gc->th)
 102
 103 #define l_isfalse(o)    (ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))
 104
 105 /*
 106 ** for internal debug only
 107 */
 108 #define checkconsistency(obj) \
 109   lua_assert(!iscollectable(obj) || (ttype(obj) == (obj)->value.gc->gch.tt))
 110
 111 #define checkliveness(g,obj) \
 112   lua_assert(!iscollectable(obj) || \
 113   ((ttype(obj) == (obj)->value.gc->gch.tt) && !isdead(g, (obj)->value.gc)))
 114
 115
 116 /* Macros to set values */
 117 #define setnilvalue(obj) ((obj)->tt=LUA_TNIL)
 118
 119 #define setnvalue(obj,x) \
 120   { TValue *i_o=(obj); i_o->value.n=(x); i_o->tt=LUA_TNUMBER; }
 121
 122 #define setpvalue(obj,x) \
 123   { TValue *i_o=(obj); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
 124
 125 #define setbvalue(obj,x) \
 126   { TValue *i_o=(obj); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
 127
 128 #define setsvalue(L,obj,x) \
 129   { TValue *i_o=(obj); \
 130     i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TSTRING; \
 131     checkliveness(G(L),i_o); }
 132
 133 #define setuvalue(L,obj,x) \
 134   { TValue *i_o=(obj); \
 135     i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TUSERDATA; \
 136     checkliveness(G(L),i_o); }
 137
 138 #define setthvalue(L,obj,x) \
 139   { TValue *i_o=(obj); \
 140     i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTHREAD; \
 141     checkliveness(G(L),i_o); }
 142
 143 #define setclvalue(L,obj,x) \
 144   { TValue *i_o=(obj); \
 145     i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TFUNCTION; \
 146     checkliveness(G(L),i_o); }
 147
 148 #define sethvalue(L,obj,x) \
 149   { TValue *i_o=(obj); \
 150     i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTABLE; \
 151     checkliveness(G(L),i_o); }
 152
 153 #define setptvalue(L,obj,x) \
 154   { TValue *i_o=(obj); \
 155     i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TPROTO; \
 156     checkliveness(G(L),i_o); }
 157
 158
 159
 160
 161 #define setobj(L,obj1,obj2) \
 162   { const TValue *o2=(obj2); TValue *o1=(obj1); \
 163     o1->value = o2->value; o1->tt=o2->tt; \
 164     checkliveness(G(L),o1); }
 165
 166
 167 /*
 168 ** different types of sets, according to destination
 169 */
 170
 171 /* from stack to (same) stack */
 172 #define setobjs2s       setobj
 173 /* to stack (not from same stack) */
 174 #define setobj2s        setobj
 175 #define setsvalue2s     setsvalue
 176 #define sethvalue2s     sethvalue
 177 #define setptvalue2s    setptvalue
 178 /* from table to same table */
 179 #define setobjt2t       setobj
 180 /* to table */
 181 #define setobj2t        setobj
 182 /* to new object */
 183 #define setobj2n        setobj
 184 #define setsvalue2n     setsvalue
 185
 186 #define setttype(obj, tt) (ttype(obj) = (tt))
 187
 188
 189 #define iscollectable(o)        (ttype(o) >= LUA_TSTRING)
 190
 191
 192
 193 typedef TValue *StkId;  /* index to stack elements */
 194
 195
 196 /*
 197 ** String headers for string table
 198 */
 199 typedef union TString {
 200   L_Umaxalign dummy;  /* ensures maximum alignment for strings */
 201   struct {
 202     CommonHeader;
 203     lu_byte reserved;
 204     unsigned int hash;
 205     size_t len;
 206   } tsv;
 207 } TString;
 208
 209
 210 #define getstr(ts)      cast(const char *, (ts) + 1)
 211 #define svalue(o)       getstr(rawtsvalue(o))
 212
 213
 214
 215 typedef union Udata {
 216   L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */
 217   struct {
 218     CommonHeader;
 219     struct Table *metatable;
 220     struct Table *env;
 221     size_t len;
 222   } uv;
 223 } Udata;
 224
 225
 226
 227
 228 /*
 229 ** Function Prototypes
 230 */
 231 typedef struct Proto {
 232   CommonHeader;
 233   TValue *k;  /* constants used by the function */
 234   Instruction *code;
 235   struct Proto **p;  /* functions defined inside the function */
 236   int *lineinfo;  /* map from opcodes to source lines */
 237   struct LocVar *locvars;  /* information about local variables */
 238   TString **upvalues;  /* upvalue names */
 239   TString  *source;
 240   int sizeupvalues;
 241   int sizek;  /* size of `k' */
 242   int sizecode;
 243   int sizelineinfo;
 244   int sizep;  /* size of `p' */
 245   int sizelocvars;
 246   int linedefined;
 247   int lastlinedefined;
 248   GCObject *gclist;
 249   lu_byte nups;  /* number of upvalues */
 250   lu_byte numparams;
 251   lu_byte is_vararg;
 252   lu_byte maxstacksize;
 253 } Proto;
 254
 255
 256 /* masks for new-style vararg */
 257 #define VARARG_HASARG           1
 258 #define VARARG_ISVARARG         2
 259 #define VARARG_NEEDSARG         4
 260
 261
 262 typedef struct LocVar {
 263   TString *varname;
 264   int startpc;  /* first point where variable is active */
 265   int endpc;    /* first point where variable is dead */
 266 } LocVar;
 267
 268
 269
 270 /*
 271 ** Upvalues
 272 */
 273
 274 typedef struct UpVal {
 275   CommonHeader;
 276   TValue *v;  /* points to stack or to its own value */
 277   union {
 278     TValue value;  /* the value (when closed) */
 279     struct {  /* double linked list (when open) */
 280       struct UpVal *prev;
 281       struct UpVal *next;
 282     } l;
 283   } u;
 284 } UpVal;
 285
 286
 287 /*
 288 ** Closures
 289 */
 290
 291 #define ClosureHeader \
 292         CommonHeader; lu_byte isC; lu_byte nupvalues; GCObject *gclist; \
 293         struct Table *env
 294
 295 typedef struct CClosure {
 296   ClosureHeader;
 297   lua_CFunction f;
 298   TValue upvalue[1];
 299 } CClosure;
 300
 301
 302 typedef struct LClosure {
 303   ClosureHeader;
 304   struct Proto *p;
 305   UpVal *upvals[1];
 306 } LClosure;
 307
 308
 309 typedef union Closure {
 310   CClosure c;
 311   LClosure l;
 312 } Closure;
 313
 314
 315 #define iscfunction(o)  (ttype(o) == LUA_TFUNCTION && clvalue(o)->c.isC)
 316 #define isLfunction(o)  (ttype(o) == LUA_TFUNCTION && !clvalue(o)->c.isC)
 317
 318
 319 /*
 320 ** Tables
 321 */
 322
 323 typedef union TKey {
 324   struct {
 325     TValuefields;
 326     struct Node *next;  /* for chaining */
 327   } nk;
 328   TValue tvk;
 329 } TKey;
 330
 331
 332 typedef struct Node {
 333   TValue i_val;
 334   TKey i_key;
 335 } Node;
 336
 337
 338 typedef struct Table {
 339   CommonHeader;
 340   lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
 341   lu_byte lsizenode;  /* log2 of size of `node' array */
 342   struct Table *metatable;
 343   TValue *array;  /* array part */
 344   Node *node;
 345   Node *lastfree;  /* any free position is before this position */
 346   GCObject *gclist;
 347   int sizearray;  /* size of `array' array */
 348 } Table;
 349
 350
 351
 352 /*
 353 ** `module' operation for hashing (size is always a power of 2)
 354 */
 355 #define lmod(s,size) \
 356         (check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1)))))
 357
 358
 359 #define twoto(x)        (1<<(x))
 360 #define sizenode(t)     (twoto((t)->lsizenode))
 361
 362
 363 #define luaO_nilobject          (&luaO_nilobject_)
 364
 365 LUAI_DATA const TValue luaO_nilobject_;
 366
 367 #define ceillog2(x)     (luaO_log2((x)-1) + 1)
 368
 369 LUAI_FUNC int luaO_log2 (unsigned int x);
 370 LUAI_FUNC int luaO_int2fb (unsigned int x);
 371 LUAI_FUNC int luaO_fb2int (int x);
 372 LUAI_FUNC int luaO_rawequalObj (const TValue *t1, const TValue *t2);
 373 LUAI_FUNC int luaO_str2d (const char *s, lua_Number *result);
 374 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
 375                                                        va_list argp);
 376 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
 377 LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);
 378
 379
 380 #endif
 381