1 /* 2 ** $Id: lobject.h,v 2.117 2016/08/01 19:51:24 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 /* 20 ** Extra tags for non-values 21 */ 22 #define LUA_TPROTO LUA_NUMTAGS /* function prototypes */ 23 #define LUA_TDEADKEY (LUA_NUMTAGS+1) /* removed keys in tables */ 24 25 /* 26 ** number of all possible tags (including LUA_TNONE but excluding DEADKEY) 27 */ 28 #define LUA_TOTALTAGS (LUA_TPROTO + 2) 29 30 31 /* 32 ** tags for Tagged Values have the following use of bits: 33 ** bits 0-3: actual tag (a LUA_T* value) 34 ** bits 4-5: variant bits 35 ** bit 6: whether value is collectable 36 */ 37 38 39 /* 40 ** LUA_TFUNCTION variants: 41 ** 0 - Lua function 42 ** 1 - light C function 43 ** 2 - regular C function (closure) 44 */ 45 46 /* Variant tags for functions */ 47 #define LUA_TLCL (LUA_TFUNCTION | (0 << 4)) /* Lua closure */ 48 #define LUA_TLCF (LUA_TFUNCTION | (1 << 4)) /* light C function */ 49 #define LUA_TCCL (LUA_TFUNCTION | (2 << 4)) /* C closure */ 50 51 52 /* Variant tags for strings */ 53 #define LUA_TSHRSTR (LUA_TSTRING | (0 << 4)) /* short strings */ 54 #define LUA_TLNGSTR (LUA_TSTRING | (1 << 4)) /* long strings */ 55 56 57 /* Variant tags for numbers */ 58 #define LUA_TNUMFLT (LUA_TNUMBER | (0 << 4)) /* float numbers */ 59 #define LUA_TNUMINT (LUA_TNUMBER | (1 << 4)) /* integer numbers */ 60 61 62 /* Bit mark for collectable types */ 63 #define BIT_ISCOLLECTABLE (1 << 6) 64 65 /* mark a tag as collectable */ 66 #define ctb(t) ((t) | BIT_ISCOLLECTABLE) 67 68 69 /* 70 ** Common type for all collectable objects 71 */ 72 typedef struct GCObject GCObject; 73 74 75 /* 76 ** Common Header for all collectable objects (in macro form, to be 77 ** included in other objects) 78 */ 79 #define CommonHeader GCObject *next; lu_byte tt; lu_byte marked 80 81 82 /* 83 ** Common type has only the common header 84 */ 85 struct GCObject { 86 CommonHeader; 87 }; 88 89 90 91 92 /* 93 ** Tagged Values. This is the basic representation of values in Lua, 94 ** an actual value plus a tag with its type. 95 */ 96 97 /* 98 ** Union of all Lua values 99 */ 100 typedef union Value { 101 GCObject *gc; /* collectable objects */ 102 void *p; /* light userdata */ 103 int b; /* booleans */ 104 lua_CFunction f; /* light C functions */ 105 lua_Integer i; /* integer numbers */ 106 lua_Number n; /* float numbers */ 107 } Value; 108 109 110 #define TValuefields Value value_; int tt_ 111 112 113 typedef struct lua_TValue { 114 TValuefields; 115 } TValue; 116 117 118 119 /* macro defining a nil value */ 120 #define NILCONSTANT {NULL}, LUA_TNIL 121 122 123 #define val_(o) ((o)->value_) 124 125 126 /* raw type tag of a TValue */ 127 #define rttype(o) ((o)->tt_) 128 129 /* tag with no variants (bits 0-3) */ 130 #define novariant(x) ((x) & 0x0F) 131 132 /* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */ 133 #define ttype(o) (rttype(o) & 0x3F) 134 135 /* type tag of a TValue with no variants (bits 0-3) */ 136 #define ttnov(o) (novariant(rttype(o))) 137 138 139 /* Macros to test type */ 140 #define checktag(o,t) (rttype(o) == (t)) 141 #define checktype(o,t) (ttnov(o) == (t)) 142 #define ttisnumber(o) checktype((o), LUA_TNUMBER) 143 #define ttisfloat(o) checktag((o), LUA_TNUMFLT) 144 #define ttisinteger(o) checktag((o), LUA_TNUMINT) 145 #define ttisnil(o) checktag((o), LUA_TNIL) 146 #define ttisboolean(o) checktag((o), LUA_TBOOLEAN) 147 #define ttislightuserdata(o) checktag((o), LUA_TLIGHTUSERDATA) 148 #define ttisstring(o) checktype((o), LUA_TSTRING) 149 #define ttisshrstring(o) checktag((o), ctb(LUA_TSHRSTR)) 150 #define ttislngstring(o) checktag((o), ctb(LUA_TLNGSTR)) 151 #define ttistable(o) checktag((o), ctb(LUA_TTABLE)) 152 #define ttisfunction(o) checktype(o, LUA_TFUNCTION) 153 #define ttisclosure(o) ((rttype(o) & 0x1F) == LUA_TFUNCTION) 154 #define ttisCclosure(o) checktag((o), ctb(LUA_TCCL)) 155 #define ttisLclosure(o) checktag((o), ctb(LUA_TLCL)) 156 #define ttislcf(o) checktag((o), LUA_TLCF) 157 #define ttisfulluserdata(o) checktag((o), ctb(LUA_TUSERDATA)) 158 #define ttisthread(o) checktag((o), ctb(LUA_TTHREAD)) 159 #define ttisdeadkey(o) checktag((o), LUA_TDEADKEY) 160 161 162 /* Macros to access values */ 163 #define ivalue(o) check_exp(ttisinteger(o), val_(o).i) 164 #define fltvalue(o) check_exp(ttisfloat(o), val_(o).n) 165 #define nvalue(o) check_exp(ttisnumber(o), \ 166 (ttisinteger(o) ? cast_num(ivalue(o)) : fltvalue(o))) 167 #define gcvalue(o) check_exp(iscollectable(o), val_(o).gc) 168 #define pvalue(o) check_exp(ttislightuserdata(o), val_(o).p) 169 #define tsvalue(o) check_exp(ttisstring(o), gco2ts(val_(o).gc)) 170 #define uvalue(o) check_exp(ttisfulluserdata(o), gco2u(val_(o).gc)) 171 #define clvalue(o) check_exp(ttisclosure(o), gco2cl(val_(o).gc)) 172 #define clLvalue(o) check_exp(ttisLclosure(o), gco2lcl(val_(o).gc)) 173 #define clCvalue(o) check_exp(ttisCclosure(o), gco2ccl(val_(o).gc)) 174 #define fvalue(o) check_exp(ttislcf(o), val_(o).f) 175 #define hvalue(o) check_exp(ttistable(o), gco2t(val_(o).gc)) 176 #define bvalue(o) check_exp(ttisboolean(o), val_(o).b) 177 #define thvalue(o) check_exp(ttisthread(o), gco2th(val_(o).gc)) 178 /* a dead value may get the 'gc' field, but cannot access its contents */ 179 #define deadvalue(o) check_exp(ttisdeadkey(o), cast(void *, val_(o).gc)) 180 181 #define l_isfalse(o) (ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0)) 182 183 184 #define iscollectable(o) (rttype(o) & BIT_ISCOLLECTABLE) 185 186 187 /* Macros for internal tests */ 188 #define righttt(obj) (ttype(obj) == gcvalue(obj)->tt) 189 190 #define checkliveness(L,obj) \ 191 lua_longassert(!iscollectable(obj) || \ 192 (righttt(obj) && (L == NULL || !isdead(G(L),gcvalue(obj))))) 193 194 195 /* Macros to set values */ 196 #define settt_(o,t) ((o)->tt_=(t)) 197 198 #define setfltvalue(obj,x) \ 199 { TValue *io=(obj); val_(io).n=(x); settt_(io, LUA_TNUMFLT); } 200 201 #define chgfltvalue(obj,x) \ 202 { TValue *io=(obj); lua_assert(ttisfloat(io)); val_(io).n=(x); } 203 204 #define setivalue(obj,x) \ 205 { TValue *io=(obj); val_(io).i=(x); settt_(io, LUA_TNUMINT); } 206 207 #define chgivalue(obj,x) \ 208 { TValue *io=(obj); lua_assert(ttisinteger(io)); val_(io).i=(x); } 209 210 #define setnilvalue(obj) settt_(obj, LUA_TNIL) 211 212 #define setfvalue(obj,x) \ 213 { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); } 214 215 #define setpvalue(obj,x) \ 216 { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); } 217 218 #define setbvalue(obj,x) \ 219 { TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); } 220 221 #define setgcovalue(L,obj,x) \ 222 { TValue *io = (obj); GCObject *i_g=(x); \ 223 val_(io).gc = i_g; settt_(io, ctb(i_g->tt)); } 224 225 #define setsvalue(L,obj,x) \ 226 { TValue *io = (obj); TString *x_ = (x); \ 227 val_(io).gc = obj2gco(x_); settt_(io, ctb(x_->tt)); \ 228 checkliveness(L,io); } 229 230 #define setuvalue(L,obj,x) \ 231 { TValue *io = (obj); Udata *x_ = (x); \ 232 val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TUSERDATA)); \ 233 checkliveness(L,io); } 234 235 #define setthvalue(L,obj,x) \ 236 { TValue *io = (obj); lua_State *x_ = (x); \ 237 val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TTHREAD)); \ 238 checkliveness(L,io); } 239 240 #define setclLvalue(L,obj,x) \ 241 { TValue *io = (obj); LClosure *x_ = (x); \ 242 val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TLCL)); \ 243 checkliveness(L,io); } 244 245 #define setclCvalue(L,obj,x) \ 246 { TValue *io = (obj); CClosure *x_ = (x); \ 247 val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TCCL)); \ 248 checkliveness(L,io); } 249 250 #define sethvalue(L,obj,x) \ 251 { TValue *io = (obj); Table *x_ = (x); \ 252 val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TTABLE)); \ 253 checkliveness(L,io); } 254 255 #define setdeadvalue(obj) settt_(obj, LUA_TDEADKEY) 256 257 258 259 #define setobj(L,obj1,obj2) \ 260 { TValue *io1=(obj1); *io1 = *(obj2); \ 261 (void)L; checkliveness(L,io1); } 262 263 264 /* 265 ** different types of assignments, according to destination 266 */ 267 268 /* from stack to (same) stack */ 269 #define setobjs2s setobj 270 /* to stack (not from same stack) */ 271 #define setobj2s setobj 272 #define setsvalue2s setsvalue 273 #define sethvalue2s sethvalue 274 #define setptvalue2s setptvalue 275 /* from table to same table */ 276 #define setobjt2t setobj 277 /* to new object */ 278 #define setobj2n setobj 279 #define setsvalue2n setsvalue 280 281 /* to table (define it as an expression to be used in macros) */ 282 #define setobj2t(L,o1,o2) ((void)L, *(o1)=*(o2), checkliveness(L,(o1))) 283 284 285 286 287 /* 288 ** {====================================================== 289 ** types and prototypes 290 ** ======================================================= 291 */ 292 293 294 typedef TValue *StkId; /* index to stack elements */ 295 296 297 298 299 /* 300 ** Header for string value; string bytes follow the end of this structure 301 ** (aligned according to 'UTString'; see next). 302 */ 303 typedef struct TString { 304 CommonHeader; 305 lu_byte extra; /* reserved words for short strings; "has hash" for longs */ 306 lu_byte shrlen; /* length for short strings */ 307 unsigned int hash; 308 union { 309 size_t lnglen; /* length for long strings */ 310 struct TString *hnext; /* linked list for hash table */ 311 } u; 312 } TString; 313 314 315 /* 316 ** Ensures that address after this type is always fully aligned. 317 */ 318 typedef union UTString { 319 L_Umaxalign dummy; /* ensures maximum alignment for strings */ 320 TString tsv; 321 } UTString; 322 323 324 /* 325 ** Get the actual string (array of bytes) from a 'TString'. 326 ** (Access to 'extra' ensures that value is really a 'TString'.) 327 */ 328 #define getstr(ts) \ 329 check_exp(sizeof((ts)->extra), cast(char *, (ts)) + sizeof(UTString)) 330 331 332 /* get the actual string (array of bytes) from a Lua value */ 333 #define svalue(o) getstr(tsvalue(o)) 334 335 /* get string length from 'TString *s' */ 336 #define tsslen(s) ((s)->tt == LUA_TSHRSTR ? (s)->shrlen : (s)->u.lnglen) 337 338 /* get string length from 'TValue *o' */ 339 #define vslen(o) tsslen(tsvalue(o)) 340 341 342 /* 343 ** Header for userdata; memory area follows the end of this structure 344 ** (aligned according to 'UUdata'; see next). 345 */ 346 typedef struct Udata { 347 CommonHeader; 348 lu_byte ttuv_; /* user value's tag */ 349 struct Table *metatable; 350 size_t len; /* number of bytes */ 351 union Value user_; /* user value */ 352 } Udata; 353 354 355 /* 356 ** Ensures that address after this type is always fully aligned. 357 */ 358 typedef union UUdata { 359 L_Umaxalign dummy; /* ensures maximum alignment for 'local' udata */ 360 Udata uv; 361 } UUdata; 362 363 364 /* 365 ** Get the address of memory block inside 'Udata'. 366 ** (Access to 'ttuv_' ensures that value is really a 'Udata'.) 367 */ 368 #define getudatamem(u) \ 369 check_exp(sizeof((u)->ttuv_), (cast(char*, (u)) + sizeof(UUdata))) 370 371 #define setuservalue(L,u,o) \ 372 { const TValue *io=(o); Udata *iu = (u); \ 373 iu->user_ = io->value_; iu->ttuv_ = rttype(io); \ 374 checkliveness(L,io); } 375 376 377 #define getuservalue(L,u,o) \ 378 { TValue *io=(o); const Udata *iu = (u); \ 379 io->value_ = iu->user_; settt_(io, iu->ttuv_); \ 380 checkliveness(L,io); } 381 382 383 /* 384 ** Description of an upvalue for function prototypes 385 */ 386 typedef struct Upvaldesc { 387 TString *name; /* upvalue name (for debug information) */ 388 lu_byte instack; /* whether it is in stack (register) */ 389 lu_byte idx; /* index of upvalue (in stack or in outer function's list) */ 390 } Upvaldesc; 391 392 393 /* 394 ** Description of a local variable for function prototypes 395 ** (used for debug information) 396 */ 397 typedef struct LocVar { 398 TString *varname; 399 int startpc; /* first point where variable is active */ 400 int endpc; /* first point where variable is dead */ 401 } LocVar; 402 403 404 /* 405 ** Function Prototypes 406 */ 407 typedef struct Proto { 408 CommonHeader; 409 lu_byte numparams; /* number of fixed parameters */ 410 lu_byte is_vararg; 411 lu_byte maxstacksize; /* number of registers needed by this function */ 412 int sizeupvalues; /* size of 'upvalues' */ 413 int sizek; /* size of 'k' */ 414 int sizecode; 415 int sizelineinfo; 416 int sizep; /* size of 'p' */ 417 int sizelocvars; 418 int linedefined; /* debug information */ 419 int lastlinedefined; /* debug information */ 420 TValue *k; /* constants used by the function */ 421 Instruction *code; /* opcodes */ 422 struct Proto **p; /* functions defined inside the function */ 423 int *lineinfo; /* map from opcodes to source lines (debug information) */ 424 LocVar *locvars; /* information about local variables (debug information) */ 425 Upvaldesc *upvalues; /* upvalue information */ 426 struct LClosure *cache; /* last-created closure with this prototype */ 427 TString *source; /* used for debug information */ 428 GCObject *gclist; 429 } Proto; 430 431 432 433 /* 434 ** Lua Upvalues 435 */ 436 typedef struct UpVal UpVal; 437 438 439 /* 440 ** Closures 441 */ 442 443 #define ClosureHeader \ 444 CommonHeader; lu_byte nupvalues; GCObject *gclist 445 446 typedef struct CClosure { 447 ClosureHeader; 448 lua_CFunction f; 449 TValue upvalue[1]; /* list of upvalues */ 450 } CClosure; 451 452 453 typedef struct LClosure { 454 ClosureHeader; 455 struct Proto *p; 456 UpVal *upvals[1]; /* list of upvalues */ 457 } LClosure; 458 459 460 typedef union Closure { 461 CClosure c; 462 LClosure l; 463 } Closure; 464 465 466 #define isLfunction(o) ttisLclosure(o) 467 468 #define getproto(o) (clLvalue(o)->p) 469 470 471 /* 472 ** Tables 473 */ 474 475 typedef union TKey { 476 struct { 477 TValuefields; 478 int next; /* for chaining (offset for next node) */ 479 } nk; 480 TValue tvk; 481 } TKey; 482 483 484 /* copy a value into a key without messing up field 'next' */ 485 #define setnodekey(L,key,obj) \ 486 { TKey *k_=(key); const TValue *io_=(obj); \ 487 k_->nk.value_ = io_->value_; k_->nk.tt_ = io_->tt_; \ 488 (void)L; checkliveness(L,io_); } 489 490 491 typedef struct Node { 492 TValue i_val; 493 TKey i_key; 494 } Node; 495 496 497 typedef struct Table { 498 CommonHeader; 499 lu_byte flags; /* 1<<p means tagmethod(p) is not present */ 500 lu_byte lsizenode; /* log2 of size of 'node' array */ 501 unsigned int sizearray; /* size of 'array' array */ 502 TValue *array; /* array part */ 503 Node *node; 504 Node *lastfree; /* any free position is before this position */ 505 struct Table *metatable; 506 GCObject *gclist; 507 } Table; 508 509 510 511 /* 512 ** 'module' operation for hashing (size is always a power of 2) 513 */ 514 #define lmod(s,size) \ 515 (check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1))))) 516 517 518 #define twoto(x) (1<<(x)) 519 #define sizenode(t) (twoto((t)->lsizenode)) 520 521 522 /* 523 ** (address of) a fixed nil value 524 */ 525 #define luaO_nilobject (&luaO_nilobject_) 526 527 528 LUAI_DDEC const TValue luaO_nilobject_; 529 530 /* size of buffer for 'luaO_utf8esc' function */ 531 #define UTF8BUFFSZ 8 532 533 LUAI_FUNC int luaO_int2fb (unsigned int x); 534 LUAI_FUNC int luaO_fb2int (int x); 535 LUAI_FUNC int luaO_utf8esc (char *buff, unsigned long x); 536 LUAI_FUNC int luaO_ceillog2 (unsigned int x); 537 LUAI_FUNC void luaO_arith (lua_State *L, int op, const TValue *p1, 538 const TValue *p2, TValue *res); 539 LUAI_FUNC size_t luaO_str2num (const char *s, TValue *o); 540 LUAI_FUNC int luaO_hexavalue (int c); 541 LUAI_FUNC void luaO_tostring (lua_State *L, StkId obj); 542 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt, 543 va_list argp); 544 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...); 545 LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len); 546 547 548 #endif 549