1/*
2** $Id: lobject.h,v 2.117.1.1 2017/04/19 17:39:34 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*/
72typedef 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*/
85struct 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*/
100typedef 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
113typedef 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
294typedef 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*/
303typedef 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*/
318typedef 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*/
346typedef 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*/
358typedef 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*/
386typedef 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*/
397typedef 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*/
407typedef 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*/
436typedef struct UpVal UpVal;
437
438
439/*
440** Closures
441*/
442
443#define ClosureHeader \
444 CommonHeader; lu_byte nupvalues; GCObject *gclist
445
446typedef struct CClosure {
447 ClosureHeader;
448 lua_CFunction f;
449 TValue upvalue[1]; /* list of upvalues */
450} CClosure;
451
452
453typedef struct LClosure {
454 ClosureHeader;
455 struct Proto *p;
456 UpVal *upvals[1]; /* list of upvalues */
457} LClosure;
458
459
460typedef 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
475typedef 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
491typedef struct Node {
492 TValue i_val;
493 TKey i_key;
494} Node;
495
496
497typedef 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
528LUAI_DDEC const TValue luaO_nilobject_;
529
530/* size of buffer for 'luaO_utf8esc' function */
531#define UTF8BUFFSZ 8
532
533LUAI_FUNC int luaO_int2fb (unsigned int x);
534LUAI_FUNC int luaO_fb2int (int x);
535LUAI_FUNC int luaO_utf8esc (char *buff, unsigned long x);
536LUAI_FUNC int luaO_ceillog2 (unsigned int x);
537LUAI_FUNC void luaO_arith (lua_State *L, int op, const TValue *p1,
538 const TValue *p2, TValue *res);
539LUAI_FUNC size_t luaO_str2num (const char *s, TValue *o);
540LUAI_FUNC int luaO_hexavalue (int c);
541LUAI_FUNC void luaO_tostring (lua_State *L, StkId obj);
542LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
543 va_list argp);
544LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
545LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);
546
547
548#endif
549
550