ba8b5c17 |
1 | /* |
2 | ** $Id: lobject.h,v 2.71 2012/09/11 18:21:44 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 |
23 | #define LUA_TUPVAL (LUA_NUMTAGS+1) |
24 | #define LUA_TDEADKEY (LUA_NUMTAGS+2) |
25 | |
26 | /* |
27 | ** number of all possible tags (including LUA_TNONE but excluding DEADKEY) |
28 | */ |
29 | #define LUA_TOTALTAGS (LUA_TUPVAL+2) |
30 | |
31 | |
32 | /* |
33 | ** tags for Tagged Values have the following use of bits: |
34 | ** bits 0-3: actual tag (a LUA_T* value) |
35 | ** bits 4-5: variant bits |
36 | ** bit 6: whether value is collectable |
37 | */ |
38 | |
39 | #define VARBITS (3 << 4) |
40 | |
41 | |
42 | /* |
43 | ** LUA_TFUNCTION variants: |
44 | ** 0 - Lua function |
45 | ** 1 - light C function |
46 | ** 2 - regular C function (closure) |
47 | */ |
48 | |
49 | /* Variant tags for functions */ |
50 | #define LUA_TLCL (LUA_TFUNCTION | (0 << 4)) /* Lua closure */ |
51 | #define LUA_TLCF (LUA_TFUNCTION | (1 << 4)) /* light C function */ |
52 | #define LUA_TCCL (LUA_TFUNCTION | (2 << 4)) /* C closure */ |
53 | |
54 | |
55 | /* Variant tags for strings */ |
56 | #define LUA_TSHRSTR (LUA_TSTRING | (0 << 4)) /* short strings */ |
57 | #define LUA_TLNGSTR (LUA_TSTRING | (1 << 4)) /* long strings */ |
58 | |
59 | |
60 | /* Bit mark for collectable types */ |
61 | #define BIT_ISCOLLECTABLE (1 << 6) |
62 | |
63 | /* mark a tag as collectable */ |
64 | #define ctb(t) ((t) | BIT_ISCOLLECTABLE) |
65 | |
66 | |
67 | /* |
68 | ** Union of all collectable objects |
69 | */ |
70 | typedef union GCObject GCObject; |
71 | |
72 | |
73 | /* |
74 | ** Common Header for all collectable objects (in macro form, to be |
75 | ** included in other objects) |
76 | */ |
77 | #define CommonHeader GCObject *next; lu_byte tt; lu_byte marked |
78 | |
79 | |
80 | /* |
81 | ** Common header in struct form |
82 | */ |
83 | typedef struct GCheader { |
84 | CommonHeader; |
85 | } GCheader; |
86 | |
87 | |
88 | |
89 | /* |
90 | ** Union of all Lua values |
91 | */ |
92 | typedef union Value Value; |
93 | |
94 | |
95 | #define numfield lua_Number n; /* numbers */ |
96 | |
97 | |
98 | |
99 | /* |
100 | ** Tagged Values. This is the basic representation of values in Lua, |
101 | ** an actual value plus a tag with its type. |
102 | */ |
103 | |
104 | #define TValuefields Value value_; int tt_ |
105 | |
106 | typedef struct lua_TValue TValue; |
107 | |
108 | |
109 | /* macro defining a nil value */ |
110 | #define NILCONSTANT {NULL}, LUA_TNIL |
111 | |
112 | |
113 | #define val_(o) ((o)->value_) |
114 | #define num_(o) (val_(o).n) |
115 | |
116 | |
117 | /* raw type tag of a TValue */ |
118 | #define rttype(o) ((o)->tt_) |
119 | |
120 | /* tag with no variants (bits 0-3) */ |
121 | #define novariant(x) ((x) & 0x0F) |
122 | |
123 | /* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */ |
124 | #define ttype(o) (rttype(o) & 0x3F) |
125 | |
126 | /* type tag of a TValue with no variants (bits 0-3) */ |
127 | #define ttypenv(o) (novariant(rttype(o))) |
128 | |
129 | |
130 | /* Macros to test type */ |
131 | #define checktag(o,t) (rttype(o) == (t)) |
132 | #define checktype(o,t) (ttypenv(o) == (t)) |
133 | #define ttisnumber(o) checktag((o), LUA_TNUMBER) |
134 | #define ttisnil(o) checktag((o), LUA_TNIL) |
135 | #define ttisboolean(o) checktag((o), LUA_TBOOLEAN) |
136 | #define ttislightuserdata(o) checktag((o), LUA_TLIGHTUSERDATA) |
137 | #define ttisstring(o) checktype((o), LUA_TSTRING) |
138 | #define ttisshrstring(o) checktag((o), ctb(LUA_TSHRSTR)) |
139 | #define ttislngstring(o) checktag((o), ctb(LUA_TLNGSTR)) |
140 | #define ttistable(o) checktag((o), ctb(LUA_TTABLE)) |
141 | #define ttisfunction(o) checktype(o, LUA_TFUNCTION) |
142 | #define ttisclosure(o) ((rttype(o) & 0x1F) == LUA_TFUNCTION) |
143 | #define ttisCclosure(o) checktag((o), ctb(LUA_TCCL)) |
144 | #define ttisLclosure(o) checktag((o), ctb(LUA_TLCL)) |
145 | #define ttislcf(o) checktag((o), LUA_TLCF) |
146 | #define ttisuserdata(o) checktag((o), ctb(LUA_TUSERDATA)) |
147 | #define ttisthread(o) checktag((o), ctb(LUA_TTHREAD)) |
148 | #define ttisdeadkey(o) checktag((o), LUA_TDEADKEY) |
149 | |
150 | #define ttisequal(o1,o2) (rttype(o1) == rttype(o2)) |
151 | |
152 | /* Macros to access values */ |
153 | #define nvalue(o) check_exp(ttisnumber(o), num_(o)) |
154 | #define gcvalue(o) check_exp(iscollectable(o), val_(o).gc) |
155 | #define pvalue(o) check_exp(ttislightuserdata(o), val_(o).p) |
156 | #define rawtsvalue(o) check_exp(ttisstring(o), &val_(o).gc->ts) |
157 | #define tsvalue(o) (&rawtsvalue(o)->tsv) |
158 | #define rawuvalue(o) check_exp(ttisuserdata(o), &val_(o).gc->u) |
159 | #define uvalue(o) (&rawuvalue(o)->uv) |
160 | #define clvalue(o) check_exp(ttisclosure(o), &val_(o).gc->cl) |
161 | #define clLvalue(o) check_exp(ttisLclosure(o), &val_(o).gc->cl.l) |
162 | #define clCvalue(o) check_exp(ttisCclosure(o), &val_(o).gc->cl.c) |
163 | #define fvalue(o) check_exp(ttislcf(o), val_(o).f) |
164 | #define hvalue(o) check_exp(ttistable(o), &val_(o).gc->h) |
165 | #define bvalue(o) check_exp(ttisboolean(o), val_(o).b) |
166 | #define thvalue(o) check_exp(ttisthread(o), &val_(o).gc->th) |
167 | /* a dead value may get the 'gc' field, but cannot access its contents */ |
168 | #define deadvalue(o) check_exp(ttisdeadkey(o), cast(void *, val_(o).gc)) |
169 | |
170 | #define l_isfalse(o) (ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0)) |
171 | |
172 | |
173 | #define iscollectable(o) (rttype(o) & BIT_ISCOLLECTABLE) |
174 | |
175 | |
176 | /* Macros for internal tests */ |
177 | #define righttt(obj) (ttype(obj) == gcvalue(obj)->gch.tt) |
178 | |
179 | #define checkliveness(g,obj) \ |
180 | lua_longassert(!iscollectable(obj) || \ |
181 | (righttt(obj) && !isdead(g,gcvalue(obj)))) |
182 | |
183 | |
184 | /* Macros to set values */ |
185 | #define settt_(o,t) ((o)->tt_=(t)) |
186 | |
187 | #define setnvalue(obj,x) \ |
188 | { TValue *io=(obj); num_(io)=(x); settt_(io, LUA_TNUMBER); } |
189 | |
190 | #define setnilvalue(obj) settt_(obj, LUA_TNIL) |
191 | |
192 | #define setfvalue(obj,x) \ |
193 | { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); } |
194 | |
195 | #define setpvalue(obj,x) \ |
196 | { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); } |
197 | |
198 | #define setbvalue(obj,x) \ |
199 | { TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); } |
200 | |
201 | #define setgcovalue(L,obj,x) \ |
202 | { TValue *io=(obj); GCObject *i_g=(x); \ |
203 | val_(io).gc=i_g; settt_(io, ctb(gch(i_g)->tt)); } |
204 | |
205 | #define setsvalue(L,obj,x) \ |
206 | { TValue *io=(obj); \ |
207 | TString *x_ = (x); \ |
208 | val_(io).gc=cast(GCObject *, x_); settt_(io, ctb(x_->tsv.tt)); \ |
209 | checkliveness(G(L),io); } |
210 | |
211 | #define setuvalue(L,obj,x) \ |
212 | { TValue *io=(obj); \ |
213 | val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TUSERDATA)); \ |
214 | checkliveness(G(L),io); } |
215 | |
216 | #define setthvalue(L,obj,x) \ |
217 | { TValue *io=(obj); \ |
218 | val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTHREAD)); \ |
219 | checkliveness(G(L),io); } |
220 | |
221 | #define setclLvalue(L,obj,x) \ |
222 | { TValue *io=(obj); \ |
223 | val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TLCL)); \ |
224 | checkliveness(G(L),io); } |
225 | |
226 | #define setclCvalue(L,obj,x) \ |
227 | { TValue *io=(obj); \ |
228 | val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TCCL)); \ |
229 | checkliveness(G(L),io); } |
230 | |
231 | #define sethvalue(L,obj,x) \ |
232 | { TValue *io=(obj); \ |
233 | val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTABLE)); \ |
234 | checkliveness(G(L),io); } |
235 | |
236 | #define setdeadvalue(obj) settt_(obj, LUA_TDEADKEY) |
237 | |
238 | |
239 | |
240 | #define setobj(L,obj1,obj2) \ |
241 | { const TValue *io2=(obj2); TValue *io1=(obj1); \ |
242 | io1->value_ = io2->value_; io1->tt_ = io2->tt_; \ |
243 | checkliveness(G(L),io1); } |
244 | |
245 | |
246 | /* |
247 | ** different types of assignments, according to destination |
248 | */ |
249 | |
250 | /* from stack to (same) stack */ |
251 | #define setobjs2s setobj |
252 | /* to stack (not from same stack) */ |
253 | #define setobj2s setobj |
254 | #define setsvalue2s setsvalue |
255 | #define sethvalue2s sethvalue |
256 | #define setptvalue2s setptvalue |
257 | /* from table to same table */ |
258 | #define setobjt2t setobj |
259 | /* to table */ |
260 | #define setobj2t setobj |
261 | /* to new object */ |
262 | #define setobj2n setobj |
263 | #define setsvalue2n setsvalue |
264 | |
265 | |
266 | /* check whether a number is valid (useful only for NaN trick) */ |
267 | #define luai_checknum(L,o,c) { /* empty */ } |
268 | |
269 | |
270 | /* |
271 | ** {====================================================== |
272 | ** NaN Trick |
273 | ** ======================================================= |
274 | */ |
275 | #if defined(LUA_NANTRICK) |
276 | |
277 | /* |
278 | ** numbers are represented in the 'd_' field. All other values have the |
279 | ** value (NNMARK | tag) in 'tt__'. A number with such pattern would be |
280 | ** a "signaled NaN", which is never generated by regular operations by |
281 | ** the CPU (nor by 'strtod') |
282 | */ |
283 | |
284 | /* allows for external implementation for part of the trick */ |
285 | #if !defined(NNMARK) /* { */ |
286 | |
287 | |
288 | #if !defined(LUA_IEEEENDIAN) |
289 | #error option 'LUA_NANTRICK' needs 'LUA_IEEEENDIAN' |
290 | #endif |
291 | |
292 | |
293 | #define NNMARK 0x7FF7A500 |
294 | #define NNMASK 0x7FFFFF00 |
295 | |
296 | #undef TValuefields |
297 | #undef NILCONSTANT |
298 | |
299 | #if (LUA_IEEEENDIAN == 0) /* { */ |
300 | |
301 | /* little endian */ |
302 | #define TValuefields \ |
303 | union { struct { Value v__; int tt__; } i; double d__; } u |
304 | #define NILCONSTANT {{{NULL}, tag2tt(LUA_TNIL)}} |
305 | /* field-access macros */ |
306 | #define v_(o) ((o)->u.i.v__) |
307 | #define d_(o) ((o)->u.d__) |
308 | #define tt_(o) ((o)->u.i.tt__) |
309 | |
310 | #else /* }{ */ |
311 | |
312 | /* big endian */ |
313 | #define TValuefields \ |
314 | union { struct { int tt__; Value v__; } i; double d__; } u |
315 | #define NILCONSTANT {{tag2tt(LUA_TNIL), {NULL}}} |
316 | /* field-access macros */ |
317 | #define v_(o) ((o)->u.i.v__) |
318 | #define d_(o) ((o)->u.d__) |
319 | #define tt_(o) ((o)->u.i.tt__) |
320 | |
321 | #endif /* } */ |
322 | |
323 | #endif /* } */ |
324 | |
325 | |
326 | /* correspondence with standard representation */ |
327 | #undef val_ |
328 | #define val_(o) v_(o) |
329 | #undef num_ |
330 | #define num_(o) d_(o) |
331 | |
332 | |
333 | #undef numfield |
334 | #define numfield /* no such field; numbers are the entire struct */ |
335 | |
336 | /* basic check to distinguish numbers from non-numbers */ |
337 | #undef ttisnumber |
338 | #define ttisnumber(o) ((tt_(o) & NNMASK) != NNMARK) |
339 | |
340 | #define tag2tt(t) (NNMARK | (t)) |
341 | |
342 | #undef rttype |
343 | #define rttype(o) (ttisnumber(o) ? LUA_TNUMBER : tt_(o) & 0xff) |
344 | |
345 | #undef settt_ |
346 | #define settt_(o,t) (tt_(o) = tag2tt(t)) |
347 | |
348 | #undef setnvalue |
349 | #define setnvalue(obj,x) \ |
350 | { TValue *io_=(obj); num_(io_)=(x); lua_assert(ttisnumber(io_)); } |
351 | |
352 | #undef setobj |
353 | #define setobj(L,obj1,obj2) \ |
354 | { const TValue *o2_=(obj2); TValue *o1_=(obj1); \ |
355 | o1_->u = o2_->u; \ |
356 | checkliveness(G(L),o1_); } |
357 | |
358 | |
359 | /* |
360 | ** these redefinitions are not mandatory, but these forms are more efficient |
361 | */ |
362 | |
363 | #undef checktag |
364 | #undef checktype |
365 | #define checktag(o,t) (tt_(o) == tag2tt(t)) |
366 | #define checktype(o,t) (ctb(tt_(o) | VARBITS) == ctb(tag2tt(t) | VARBITS)) |
367 | |
368 | #undef ttisequal |
369 | #define ttisequal(o1,o2) \ |
370 | (ttisnumber(o1) ? ttisnumber(o2) : (tt_(o1) == tt_(o2))) |
371 | |
372 | |
373 | #undef luai_checknum |
374 | #define luai_checknum(L,o,c) { if (!ttisnumber(o)) c; } |
375 | |
376 | #endif |
377 | /* }====================================================== */ |
378 | |
379 | |
380 | |
381 | /* |
382 | ** {====================================================== |
383 | ** types and prototypes |
384 | ** ======================================================= |
385 | */ |
386 | |
387 | |
388 | union Value { |
389 | GCObject *gc; /* collectable objects */ |
390 | void *p; /* light userdata */ |
391 | int b; /* booleans */ |
392 | lua_CFunction f; /* light C functions */ |
393 | numfield /* numbers */ |
394 | }; |
395 | |
396 | |
397 | struct lua_TValue { |
398 | TValuefields; |
399 | }; |
400 | |
401 | |
402 | typedef TValue *StkId; /* index to stack elements */ |
403 | |
404 | |
405 | |
406 | |
407 | /* |
408 | ** Header for string value; string bytes follow the end of this structure |
409 | */ |
410 | typedef union TString { |
411 | L_Umaxalign dummy; /* ensures maximum alignment for strings */ |
412 | struct { |
413 | CommonHeader; |
414 | lu_byte extra; /* reserved words for short strings; "has hash" for longs */ |
415 | unsigned int hash; |
416 | size_t len; /* number of characters in string */ |
417 | } tsv; |
418 | } TString; |
419 | |
420 | |
421 | /* get the actual string (array of bytes) from a TString */ |
422 | #define getstr(ts) cast(const char *, (ts) + 1) |
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[1]; /* list of upvalues */ |
520 | } CClosure; |
521 | |
522 | |
523 | typedef struct LClosure { |
524 | ClosureHeader; |
525 | struct Proto *p; |
526 | UpVal *upvals[1]; /* 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 | struct Table *metatable; |
565 | TValue *array; /* array part */ |
566 | Node *node; |
567 | Node *lastfree; /* any free position is before this position */ |
568 | GCObject *gclist; |
569 | int sizearray; /* size of `array' array */ |
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 | |