1 /* 2 ** $Id: lobject.h,v 2.71.1.2 2014/05/07 14:14:58 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 "llimits.h" 13 #include <sys/lua/lua.h> 14 15 16 /* 17 ** Extra tags for non-values 18 */ 19 #define LUA_TPROTO LUA_NUMTAGS 20 #define LUA_TUPVAL (LUA_NUMTAGS+1) 21 #define LUA_TDEADKEY (LUA_NUMTAGS+2) 22 23 /* 24 ** number of all possible tags (including LUA_TNONE but excluding DEADKEY) 25 */ 26 #define LUA_TOTALTAGS (LUA_TUPVAL+2) 27 28 29 /* 30 ** tags for Tagged Values have the following use of bits: 31 ** bits 0-3: actual tag (a LUA_T* value) 32 ** bits 4-5: variant bits 33 ** bit 6: whether value is collectable 34 */ 35 36 #define VARBITS (3 << 4) 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 /* Bit mark for collectable types */ 58 #define BIT_ISCOLLECTABLE (1 << 6) 59 60 /* mark a tag as collectable */ 61 #define ctb(t) ((t) | BIT_ISCOLLECTABLE) 62 63 64 /* 65 ** Union of all collectable objects 66 */ 67 typedef union GCObject GCObject; 68 69 70 /* 71 ** Common Header for all collectable objects (in macro form, to be 72 ** included in other objects) 73 */ 74 #define CommonHeader GCObject *next; lu_byte tt; lu_byte marked 75 76 77 /* 78 ** Common header in struct form 79 */ 80 typedef struct GCheader { 81 CommonHeader; 82 } GCheader; 83 84 85 86 /* 87 ** Union of all Lua values 88 */ 89 typedef union Value Value; 90 91 92 #define numfield lua_Number n; /* numbers */ 93 94 95 96 /* 97 ** Tagged Values. This is the basic representation of values in Lua, 98 ** an actual value plus a tag with its type. 99 */ 100 101 #define TValuefields Value value_; int tt_ 102 103 typedef struct lua_TValue TValue; 104 105 106 /* macro defining a nil value */ 107 #define NILCONSTANT {NULL}, LUA_TNIL 108 109 110 #define val_(o) ((o)->value_) 111 #define num_(o) (val_(o).n) 112 113 114 /* raw type tag of a TValue */ 115 #define rttype(o) ((o)->tt_) 116 117 /* tag with no variants (bits 0-3) */ 118 #define novariant(x) ((x) & 0x0F) 119 120 /* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */ 121 #define ttype(o) (rttype(o) & 0x3F) 122 123 /* type tag of a TValue with no variants (bits 0-3) */ 124 #define ttypenv(o) (novariant(rttype(o))) 125 126 127 /* Macros to test type */ 128 #define checktag(o,t) (rttype(o) == (t)) 129 #define checktype(o,t) (ttypenv(o) == (t)) 130 #define ttisnumber(o) checktag((o), LUA_TNUMBER) 131 #define ttisnil(o) checktag((o), LUA_TNIL) 132 #define ttisboolean(o) checktag((o), LUA_TBOOLEAN) 133 #define ttislightuserdata(o) checktag((o), LUA_TLIGHTUSERDATA) 134 #define ttisstring(o) checktype((o), LUA_TSTRING) 135 #define ttisshrstring(o) checktag((o), ctb(LUA_TSHRSTR)) 136 #define ttislngstring(o) checktag((o), ctb(LUA_TLNGSTR)) 137 #define ttistable(o) checktag((o), ctb(LUA_TTABLE)) 138 #define ttisfunction(o) checktype(o, LUA_TFUNCTION) 139 #define ttisclosure(o) ((rttype(o) & 0x1F) == LUA_TFUNCTION) 140 #define ttisCclosure(o) checktag((o), ctb(LUA_TCCL)) 141 #define ttisLclosure(o) checktag((o), ctb(LUA_TLCL)) 142 #define ttislcf(o) checktag((o), LUA_TLCF) 143 #define ttisuserdata(o) checktag((o), ctb(LUA_TUSERDATA)) 144 #define ttisthread(o) checktag((o), ctb(LUA_TTHREAD)) 145 #define ttisdeadkey(o) checktag((o), LUA_TDEADKEY) 146 147 #define ttisequal(o1,o2) (rttype(o1) == rttype(o2)) 148 149 /* Macros to access values */ 150 #define nvalue(o) check_exp(ttisnumber(o), num_(o)) 151 #define gcvalue(o) check_exp(iscollectable(o), val_(o).gc) 152 #define pvalue(o) check_exp(ttislightuserdata(o), val_(o).p) 153 #define rawtsvalue(o) check_exp(ttisstring(o), &val_(o).gc->ts) 154 #define tsvalue(o) (&rawtsvalue(o)->tsv) 155 #define rawuvalue(o) check_exp(ttisuserdata(o), &val_(o).gc->u) 156 #define uvalue(o) (&rawuvalue(o)->uv) 157 #define clvalue(o) check_exp(ttisclosure(o), &val_(o).gc->cl) 158 #define clLvalue(o) check_exp(ttisLclosure(o), &val_(o).gc->cl.l) 159 #define clCvalue(o) check_exp(ttisCclosure(o), &val_(o).gc->cl.c) 160 #define fvalue(o) check_exp(ttislcf(o), val_(o).f) 161 #define hvalue(o) check_exp(ttistable(o), &val_(o).gc->h) 162 #define bvalue(o) check_exp(ttisboolean(o), val_(o).b) 163 #define thvalue(o) check_exp(ttisthread(o), &val_(o).gc->th) 164 /* a dead value may get the 'gc' field, but cannot access its contents */ 165 #define deadvalue(o) check_exp(ttisdeadkey(o), cast(void *, val_(o).gc)) 166 167 #define l_isfalse(o) (ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0)) 168 169 170 #define iscollectable(o) (rttype(o) & BIT_ISCOLLECTABLE) 171 172 173 /* Macros for internal tests */ 174 #define righttt(obj) (ttype(obj) == gcvalue(obj)->gch.tt) 175 176 #define checkliveness(g,obj) \ 177 lua_longassert(!iscollectable(obj) || \ 178 (righttt(obj) && !isdead(g,gcvalue(obj)))) 179 180 181 /* Macros to set values */ 182 #define settt_(o,t) ((o)->tt_=(t)) 183 184 #define setnvalue(obj,x) \ 185 { TValue *io=(obj); num_(io)=(x); settt_(io, LUA_TNUMBER); } 186 187 #define setnilvalue(obj) settt_(obj, LUA_TNIL) 188 189 #define setfvalue(obj,x) \ 190 { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); } 191 192 #define setpvalue(obj,x) \ 193 { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); } 194 195 #define setbvalue(obj,x) \ 196 { TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); } 197 198 #define setgcovalue(L,obj,x) \ 199 { TValue *io=(obj); GCObject *i_g=(x); \ 200 val_(io).gc=i_g; settt_(io, ctb(gch(i_g)->tt)); } 201 202 #define setsvalue(L,obj,x) \ 203 { TValue *io=(obj); \ 204 TString *x_ = (x); \ 205 val_(io).gc=cast(GCObject *, x_); settt_(io, ctb(x_->tsv.tt)); \ 206 checkliveness(G(L),io); } 207 208 #define setuvalue(L,obj,x) \ 209 { TValue *io=(obj); \ 210 val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TUSERDATA)); \ 211 checkliveness(G(L),io); } 212 213 #define setthvalue(L,obj,x) \ 214 { TValue *io=(obj); \ 215 val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTHREAD)); \ 216 checkliveness(G(L),io); } 217 218 #define setclLvalue(L,obj,x) \ 219 { TValue *io=(obj); \ 220 val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TLCL)); \ 221 checkliveness(G(L),io); } 222 223 #define setclCvalue(L,obj,x) \ 224 { TValue *io=(obj); \ 225 val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TCCL)); \ 226 checkliveness(G(L),io); } 227 228 #define sethvalue(L,obj,x) \ 229 { TValue *io=(obj); \ 230 val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTABLE)); \ 231 checkliveness(G(L),io); } 232 233 #define setdeadvalue(obj) settt_(obj, LUA_TDEADKEY) 234 235 236 237 #define setobj(L,obj1,obj2) \ 238 { const TValue *io2=(obj2); TValue *io1=(obj1); \ 239 io1->value_ = io2->value_; io1->tt_ = io2->tt_; \ 240 checkliveness(G(L),io1); } 241 242 243 /* 244 ** different types of assignments, according to destination 245 */ 246 247 /* from stack to (same) stack */ 248 #define setobjs2s setobj 249 /* to stack (not from same stack) */ 250 #define setobj2s setobj 251 #define setsvalue2s setsvalue 252 #define sethvalue2s sethvalue 253 #define setptvalue2s setptvalue 254 /* from table to same table */ 255 #define setobjt2t setobj 256 /* to table */ 257 #define setobj2t setobj 258 /* to new object */ 259 #define setobj2n setobj 260 #define setsvalue2n setsvalue 261 262 263 /* check whether a number is valid (useful only for NaN trick) */ 264 #define luai_checknum(L,o,c) { /* empty */ } 265 266 267 /* 268 ** {====================================================== 269 ** NaN Trick 270 ** ======================================================= 271 */ 272 #if defined(LUA_NANTRICK) 273 274 /* 275 ** numbers are represented in the 'd_' field. All other values have the 276 ** value (NNMARK | tag) in 'tt__'. A number with such pattern would be 277 ** a "signaled NaN", which is never generated by regular operations by 278 ** the CPU (nor by 'strtod') 279 */ 280 281 /* allows for external implementation for part of the trick */ 282 #if !defined(NNMARK) /* { */ 283 284 285 #if !defined(LUA_IEEEENDIAN) 286 #error option 'LUA_NANTRICK' needs 'LUA_IEEEENDIAN' 287 #endif 288 289 290 #define NNMARK 0x7FF7A500 291 #define NNMASK 0x7FFFFF00 292 293 #undef TValuefields 294 #undef NILCONSTANT 295 296 #if (LUA_IEEEENDIAN == 0) /* { */ 297 298 /* little endian */ 299 #define TValuefields \ 300 union { struct { Value v__; int tt__; } i; double d__; } u 301 #define NILCONSTANT {{{NULL}, tag2tt(LUA_TNIL)}} 302 /* field-access macros */ 303 #define v_(o) ((o)->u.i.v__) 304 #define d_(o) ((o)->u.d__) 305 #define tt_(o) ((o)->u.i.tt__) 306 307 #else /* }{ */ 308 309 /* big endian */ 310 #define TValuefields \ 311 union { struct { int tt__; Value v__; } i; double d__; } u 312 #define NILCONSTANT {{tag2tt(LUA_TNIL), {NULL}}} 313 /* field-access macros */ 314 #define v_(o) ((o)->u.i.v__) 315 #define d_(o) ((o)->u.d__) 316 #define tt_(o) ((o)->u.i.tt__) 317 318 #endif /* } */ 319 320 #endif /* } */ 321 322 323 /* correspondence with standard representation */ 324 #undef val_ 325 #define val_(o) v_(o) 326 #undef num_ 327 #define num_(o) d_(o) 328 329 330 #undef numfield 331 #define numfield /* no such field; numbers are the entire struct */ 332 333 /* basic check to distinguish numbers from non-numbers */ 334 #undef ttisnumber 335 #define ttisnumber(o) ((tt_(o) & NNMASK) != NNMARK) 336 337 #define tag2tt(t) (NNMARK | (t)) 338 339 #undef rttype 340 #define rttype(o) (ttisnumber(o) ? LUA_TNUMBER : tt_(o) & 0xff) 341 342 #undef settt_ 343 #define settt_(o,t) (tt_(o) = tag2tt(t)) 344 345 #undef setnvalue 346 #define setnvalue(obj,x) \ 347 { TValue *io_=(obj); num_(io_)=(x); lua_assert(ttisnumber(io_)); } 348 349 #undef setobj 350 #define setobj(L,obj1,obj2) \ 351 { const TValue *o2_=(obj2); TValue *o1_=(obj1); \ 352 o1_->u = o2_->u; \ 353 checkliveness(G(L),o1_); } 354 355 356 /* 357 ** these redefinitions are not mandatory, but these forms are more efficient 358 */ 359 360 #undef checktag 361 #undef checktype 362 #define checktag(o,t) (tt_(o) == tag2tt(t)) 363 #define checktype(o,t) (ctb(tt_(o) | VARBITS) == ctb(tag2tt(t) | VARBITS)) 364 365 #undef ttisequal 366 #define ttisequal(o1,o2) \ 367 (ttisnumber(o1) ? ttisnumber(o2) : (tt_(o1) == tt_(o2))) 368 369 370 #undef luai_checknum 371 #define luai_checknum(L,o,c) { if (!ttisnumber(o)) c; } 372 373 #endif 374 /* }====================================================== */ 375 376 377 378 /* 379 ** {====================================================== 380 ** types and prototypes 381 ** ======================================================= 382 */ 383 384 385 union Value { 386 GCObject *gc; /* collectable objects */ 387 void *p; /* light userdata */ 388 int b; /* booleans */ 389 lua_CFunction f; /* light C functions */ 390 numfield /* numbers */ 391 }; 392 393 394 struct lua_TValue { 395 TValuefields; 396 }; 397 398 399 typedef TValue *StkId; /* index to stack elements */ 400 401 402 403 404 /* 405 ** Header for string value; string bytes follow the end of this structure 406 */ 407 typedef struct TString { 408 union { 409 L_Umaxalign dummy; /* ensures maximum alignment for strings */ 410 struct { 411 CommonHeader; 412 lu_byte extra; /* reserved words for short strings; "has hash" for longs */ 413 unsigned int hash; 414 size_t len; /* number of characters in string */ 415 } tsv; 416 }; 417 char contents[]; 418 } TString; 419 420 421 /* get the actual string (array of bytes) from a TString */ 422 #define getstr(ts) ((ts)->contents) 423 424 /* get the actual string (array of bytes) from a Lua value */ 425 #define svalue(o) getstr(rawtsvalue(o)) 426 427 428 /* 429 ** Header for userdata; memory area follows the end of this structure 430 */ 431 typedef union Udata { 432 L_Umaxalign dummy; /* ensures maximum alignment for `local' udata */ 433 struct { 434 CommonHeader; 435 struct Table *metatable; 436 struct Table *env; 437 size_t len; /* number of bytes */ 438 } uv; 439 } Udata; 440 441 442 443 /* 444 ** Description of an upvalue for function prototypes 445 */ 446 typedef struct Upvaldesc { 447 TString *name; /* upvalue name (for debug information) */ 448 lu_byte instack; /* whether it is in stack */ 449 lu_byte idx; /* index of upvalue (in stack or in outer function's list) */ 450 } Upvaldesc; 451 452 453 /* 454 ** Description of a local variable for function prototypes 455 ** (used for debug information) 456 */ 457 typedef struct LocVar { 458 TString *varname; 459 int startpc; /* first point where variable is active */ 460 int endpc; /* first point where variable is dead */ 461 } LocVar; 462 463 464 /* 465 ** Function Prototypes 466 */ 467 typedef struct Proto { 468 CommonHeader; 469 TValue *k; /* constants used by the function */ 470 Instruction *code; 471 struct Proto **p; /* functions defined inside the function */ 472 int *lineinfo; /* map from opcodes to source lines (debug information) */ 473 LocVar *locvars; /* information about local variables (debug information) */ 474 Upvaldesc *upvalues; /* upvalue information */ 475 union Closure *cache; /* last created closure with this prototype */ 476 TString *source; /* used for debug information */ 477 int sizeupvalues; /* size of 'upvalues' */ 478 int sizek; /* size of `k' */ 479 int sizecode; 480 int sizelineinfo; 481 int sizep; /* size of `p' */ 482 int sizelocvars; 483 int linedefined; 484 int lastlinedefined; 485 GCObject *gclist; 486 lu_byte numparams; /* number of fixed parameters */ 487 lu_byte is_vararg; 488 lu_byte maxstacksize; /* maximum stack used by this function */ 489 } Proto; 490 491 492 493 /* 494 ** Lua Upvalues 495 */ 496 typedef struct UpVal { 497 CommonHeader; 498 TValue *v; /* points to stack or to its own value */ 499 union { 500 TValue value; /* the value (when closed) */ 501 struct { /* double linked list (when open) */ 502 struct UpVal *prev; 503 struct UpVal *next; 504 } l; 505 } u; 506 } UpVal; 507 508 509 /* 510 ** Closures 511 */ 512 513 #define ClosureHeader \ 514 CommonHeader; lu_byte nupvalues; GCObject *gclist 515 516 typedef struct CClosure { 517 ClosureHeader; 518 lua_CFunction f; 519 TValue upvalue[]; /* list of upvalues */ 520 } CClosure; 521 522 523 typedef struct LClosure { 524 ClosureHeader; 525 struct Proto *p; 526 UpVal *upvals[]; /* list of upvalues */ 527 } LClosure; 528 529 530 typedef union Closure { 531 CClosure c; 532 LClosure l; 533 } Closure; 534 535 536 #define isLfunction(o) ttisLclosure(o) 537 538 #define getproto(o) (clLvalue(o)->p) 539 540 541 /* 542 ** Tables 543 */ 544 545 typedef union TKey { 546 struct { 547 TValuefields; 548 struct Node *next; /* for chaining */ 549 } nk; 550 TValue tvk; 551 } TKey; 552 553 554 typedef struct Node { 555 TValue i_val; 556 TKey i_key; 557 } Node; 558 559 560 typedef struct Table { 561 CommonHeader; 562 lu_byte flags; /* 1<<p means tagmethod(p) is not present */ 563 lu_byte lsizenode; /* log2 of size of `node' array */ 564 int sizearray; /* size of `array' array */ 565 TValue *array; /* array part */ 566 Node *node; 567 Node *lastfree; /* any free position is before this position */ 568 struct Table *metatable; 569 GCObject *gclist; 570 } Table; 571 572 573 574 /* 575 ** `module' operation for hashing (size is always a power of 2) 576 */ 577 #define lmod(s,size) \ 578 (check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1))))) 579 580 581 #define twoto(x) (1<<(x)) 582 #define sizenode(t) (twoto((t)->lsizenode)) 583 584 585 /* 586 ** (address of) a fixed nil value 587 */ 588 #define luaO_nilobject (&luaO_nilobject_) 589 590 591 LUAI_DDEC const TValue luaO_nilobject_; 592 593 594 LUAI_FUNC int luaO_int2fb (unsigned int x); 595 LUAI_FUNC int luaO_fb2int (int x); 596 LUAI_FUNC int luaO_ceillog2 (unsigned int x); 597 LUAI_FUNC lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2); 598 LUAI_FUNC int luaO_str2d (const char *s, size_t len, lua_Number *result); 599 LUAI_FUNC int luaO_hexavalue (int c); 600 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt, 601 va_list argp); 602 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...); 603 LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len); 604 605 606 #endif 607