xref: /netbsd-src/external/mit/lua/dist/src/lobject.h (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: lobject.h,v 1.10 2018/08/04 17:30:01 alnsn Exp $	*/
2 
3 /*
4 ** Id: lobject.h,v 2.117.1.1 2017/04/19 17:39:34 roberto Exp
5 ** Type definitions for Lua objects
6 ** See Copyright Notice in lua.h
7 */
8 
9 
10 #ifndef lobject_h
11 #define lobject_h
12 
13 
14 #include <stdarg.h>
15 
16 
17 #include "llimits.h"
18 #include "lua.h"
19 
20 
21 /*
22 ** Extra tags for non-values
23 */
24 #define LUA_TPROTO	LUA_NUMTAGS		/* function prototypes */
25 #define LUA_TDEADKEY	(LUA_NUMTAGS+1)		/* removed keys in tables */
26 
27 /*
28 ** number of all possible tags (including LUA_TNONE but excluding DEADKEY)
29 */
30 #define LUA_TOTALTAGS	(LUA_TPROTO + 2)
31 
32 
33 /*
34 ** tags for Tagged Values have the following use of bits:
35 ** bits 0-3: actual tag (a LUA_T* value)
36 ** bits 4-5: variant bits
37 ** bit 6: whether value is collectable
38 */
39 
40 
41 /*
42 ** LUA_TFUNCTION variants:
43 ** 0 - Lua function
44 ** 1 - light C function
45 ** 2 - regular C function (closure)
46 */
47 
48 /* Variant tags for functions */
49 #define LUA_TLCL	(LUA_TFUNCTION | (0 << 4))  /* Lua closure */
50 #define LUA_TLCF	(LUA_TFUNCTION | (1 << 4))  /* light C function */
51 #define LUA_TCCL	(LUA_TFUNCTION | (2 << 4))  /* C closure */
52 
53 
54 /* Variant tags for strings */
55 #define LUA_TSHRSTR	(LUA_TSTRING | (0 << 4))  /* short strings */
56 #define LUA_TLNGSTR	(LUA_TSTRING | (1 << 4))  /* long strings */
57 
58 
59 /* Variant tags for numbers */
60 #ifndef _KERNEL
61 #define LUA_TNUMFLT	(LUA_TNUMBER | (0 << 4))  /* float numbers */
62 #endif /* _KERNEL */
63 #define LUA_TNUMINT	(LUA_TNUMBER | (1 << 4))  /* integer numbers */
64 
65 
66 /* Bit mark for collectable types */
67 #define BIT_ISCOLLECTABLE	(1 << 6)
68 
69 /* mark a tag as collectable */
70 #define ctb(t)			((t) | BIT_ISCOLLECTABLE)
71 
72 
73 /*
74 ** Common type for all collectable objects
75 */
76 typedef struct GCObject GCObject;
77 
78 
79 /*
80 ** Common Header for all collectable objects (in macro form, to be
81 ** included in other objects)
82 */
83 #define CommonHeader	GCObject *next; lu_byte tt; lu_byte marked
84 
85 
86 /*
87 ** Common type has only the common header
88 */
89 struct GCObject {
90   CommonHeader;
91 };
92 
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 /*
102 ** Union of all Lua values
103 */
104 typedef union Value {
105   GCObject *gc;    /* collectable objects */
106   void *p;         /* light userdata */
107   int b;           /* booleans */
108   lua_CFunction f; /* light C functions */
109   lua_Integer i;   /* integer numbers */
110 #ifndef _KERNEL
111   lua_Number n;    /* float numbers */
112 #endif /* _KERNEL */
113 } Value;
114 
115 
116 #define TValuefields	Value value_; int tt_
117 
118 
119 typedef struct lua_TValue {
120   TValuefields;
121 } TValue;
122 
123 
124 
125 /* macro defining a nil value */
126 #define NILCONSTANT	{NULL}, LUA_TNIL
127 
128 
129 #define val_(o)		((o)->value_)
130 
131 
132 /* raw type tag of a TValue */
133 #define rttype(o)	((o)->tt_)
134 
135 /* tag with no variants (bits 0-3) */
136 #define novariant(x)	((x) & 0x0F)
137 
138 /* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */
139 #define ttype(o)	(rttype(o) & 0x3F)
140 
141 /* type tag of a TValue with no variants (bits 0-3) */
142 #define ttnov(o)	(novariant(rttype(o)))
143 
144 
145 /* Macros to test type */
146 #define checktag(o,t)		(rttype(o) == (t))
147 #define checktype(o,t)		(ttnov(o) == (t))
148 #define ttisnumber(o)		checktype((o), LUA_TNUMBER)
149 #ifndef _KERNEL
150 #define ttisfloat(o)		checktag((o), LUA_TNUMFLT)
151 #endif /* _KERNEL */
152 #define ttisinteger(o)		checktag((o), LUA_TNUMINT)
153 #define ttisnil(o)		checktag((o), LUA_TNIL)
154 #define ttisboolean(o)		checktag((o), LUA_TBOOLEAN)
155 #define ttislightuserdata(o)	checktag((o), LUA_TLIGHTUSERDATA)
156 #define ttisstring(o)		checktype((o), LUA_TSTRING)
157 #define ttisshrstring(o)	checktag((o), ctb(LUA_TSHRSTR))
158 #define ttislngstring(o)	checktag((o), ctb(LUA_TLNGSTR))
159 #define ttistable(o)		checktag((o), ctb(LUA_TTABLE))
160 #define ttisfunction(o)		checktype(o, LUA_TFUNCTION)
161 #define ttisclosure(o)		((rttype(o) & 0x1F) == LUA_TFUNCTION)
162 #define ttisCclosure(o)		checktag((o), ctb(LUA_TCCL))
163 #define ttisLclosure(o)		checktag((o), ctb(LUA_TLCL))
164 #define ttislcf(o)		checktag((o), LUA_TLCF)
165 #define ttisfulluserdata(o)	checktag((o), ctb(LUA_TUSERDATA))
166 #define ttisthread(o)		checktag((o), ctb(LUA_TTHREAD))
167 #define ttisdeadkey(o)		checktag((o), LUA_TDEADKEY)
168 
169 
170 /* Macros to access values */
171 #define ivalue(o)	check_exp(ttisinteger(o), val_(o).i)
172 #ifndef _KERNEL
173 #define fltvalue(o)	check_exp(ttisfloat(o), val_(o).n)
174 #define nvalue(o)	check_exp(ttisnumber(o), \
175 	(ttisinteger(o) ? cast_num(ivalue(o)) : fltvalue(o)))
176 #else /* _KERNEL */
177 #define nvalue(o)	check_exp(ttisnumber(o), cast_num(ivalue(o)))
178 #endif /* _KERNEL */
179 #define gcvalue(o)	check_exp(iscollectable(o), val_(o).gc)
180 #define pvalue(o)	check_exp(ttislightuserdata(o), val_(o).p)
181 #define tsvalue(o)	check_exp(ttisstring(o), gco2ts(val_(o).gc))
182 #define uvalue(o)	check_exp(ttisfulluserdata(o), gco2u(val_(o).gc))
183 #define clvalue(o)	check_exp(ttisclosure(o), gco2cl(val_(o).gc))
184 #define clLvalue(o)	check_exp(ttisLclosure(o), gco2lcl(val_(o).gc))
185 #define clCvalue(o)	check_exp(ttisCclosure(o), gco2ccl(val_(o).gc))
186 #define fvalue(o)	check_exp(ttislcf(o), val_(o).f)
187 #define hvalue(o)	check_exp(ttistable(o), gco2t(val_(o).gc))
188 #define bvalue(o)	check_exp(ttisboolean(o), val_(o).b)
189 #define thvalue(o)	check_exp(ttisthread(o), gco2th(val_(o).gc))
190 /* a dead value may get the 'gc' field, but cannot access its contents */
191 #define deadvalue(o)	check_exp(ttisdeadkey(o), cast(void *, val_(o).gc))
192 
193 #define l_isfalse(o)	(ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))
194 
195 
196 #define iscollectable(o)	(rttype(o) & BIT_ISCOLLECTABLE)
197 
198 
199 /* Macros for internal tests */
200 #define righttt(obj)		(ttype(obj) == gcvalue(obj)->tt)
201 
202 #define checkliveness(L,obj) \
203 	lua_longassert(!iscollectable(obj) || \
204 		(righttt(obj) && (L == NULL || !isdead(G(L),gcvalue(obj)))))
205 
206 
207 /* Macros to set values */
208 #define settt_(o,t)	((o)->tt_=(t))
209 
210 #ifndef _KERNEL
211 #define setfltvalue(obj,x) \
212   { TValue *io=(obj); val_(io).n=(x); settt_(io, LUA_TNUMFLT); }
213 #endif /* _KERNEL */
214 
215 #define chgfltvalue(obj,x) \
216   { TValue *io=(obj); lua_assert(ttisfloat(io)); val_(io).n=(x); }
217 
218 #define setivalue(obj,x) \
219   { TValue *io=(obj); val_(io).i=(x); settt_(io, LUA_TNUMINT); }
220 
221 #define chgivalue(obj,x) \
222   { TValue *io=(obj); lua_assert(ttisinteger(io)); val_(io).i=(x); }
223 
224 #define setnilvalue(obj) settt_(obj, LUA_TNIL)
225 
226 #define setfvalue(obj,x) \
227   { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); }
228 
229 #define setpvalue(obj,x) \
230   { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); }
231 
232 #define setbvalue(obj,x) \
233   { TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); }
234 
235 #define setgcovalue(L,obj,x) \
236   { TValue *io = (obj); GCObject *i_g=(x); \
237     val_(io).gc = i_g; settt_(io, ctb(i_g->tt)); }
238 
239 #define setsvalue(L,obj,x) \
240   { TValue *io = (obj); TString *x_ = (x); \
241     val_(io).gc = obj2gco(x_); settt_(io, ctb(x_->tt)); \
242     checkliveness(L,io); }
243 
244 #define setuvalue(L,obj,x) \
245   { TValue *io = (obj); Udata *x_ = (x); \
246     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TUSERDATA)); \
247     checkliveness(L,io); }
248 
249 #define setthvalue(L,obj,x) \
250   { TValue *io = (obj); lua_State *x_ = (x); \
251     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TTHREAD)); \
252     checkliveness(L,io); }
253 
254 #define setclLvalue(L,obj,x) \
255   { TValue *io = (obj); LClosure *x_ = (x); \
256     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TLCL)); \
257     checkliveness(L,io); }
258 
259 #define setclCvalue(L,obj,x) \
260   { TValue *io = (obj); CClosure *x_ = (x); \
261     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TCCL)); \
262     checkliveness(L,io); }
263 
264 #define sethvalue(L,obj,x) \
265   { TValue *io = (obj); Table *x_ = (x); \
266     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TTABLE)); \
267     checkliveness(L,io); }
268 
269 #define setdeadvalue(obj)	settt_(obj, LUA_TDEADKEY)
270 
271 
272 
273 #define setobj(L,obj1,obj2) \
274 	{ TValue *io1=(obj1); *io1 = *(obj2); \
275 	  (void)L; checkliveness(L,io1); }
276 
277 
278 /*
279 ** different types of assignments, according to destination
280 */
281 
282 /* from stack to (same) stack */
283 #define setobjs2s	setobj
284 /* to stack (not from same stack) */
285 #define setobj2s	setobj
286 #define setsvalue2s	setsvalue
287 #define sethvalue2s	sethvalue
288 #define setptvalue2s	setptvalue
289 /* from table to same table */
290 #define setobjt2t	setobj
291 /* to new object */
292 #define setobj2n	setobj
293 #define setsvalue2n	setsvalue
294 
295 /* to table (define it as an expression to be used in macros) */
296 #define setobj2t(L,o1,o2)  ((void)L, *(o1)=*(o2), checkliveness(L,(o1)))
297 
298 
299 
300 
301 /*
302 ** {======================================================
303 ** types and prototypes
304 ** =======================================================
305 */
306 
307 
308 typedef TValue *StkId;  /* index to stack elements */
309 
310 
311 
312 
313 /*
314 ** Header for string value; string bytes follow the end of this structure
315 ** (aligned according to 'UTString'; see next).
316 */
317 typedef struct TString {
318   CommonHeader;
319   lu_byte extra;  /* reserved words for short strings; "has hash" for longs */
320   lu_byte shrlen;  /* length for short strings */
321   unsigned int hash;
322   union {
323     size_t lnglen;  /* length for long strings */
324     struct TString *hnext;  /* linked list for hash table */
325   } u;
326 } TString;
327 
328 
329 /*
330 ** Ensures that address after this type is always fully aligned.
331 */
332 typedef union UTString {
333   L_Umaxalign dummy;  /* ensures maximum alignment for strings */
334   TString tsv;
335 } UTString;
336 
337 
338 /*
339 ** Get the actual string (array of bytes) from a 'TString'.
340 ** (Access to 'extra' ensures that value is really a 'TString'.)
341 */
342 #define getstr(ts)  \
343   check_exp(sizeof((ts)->extra), cast(char *, (ts)) + sizeof(UTString))
344 
345 
346 /* get the actual string (array of bytes) from a Lua value */
347 #define svalue(o)       getstr(tsvalue(o))
348 
349 /* get string length from 'TString *s' */
350 #define tsslen(s)	((s)->tt == LUA_TSHRSTR ? (s)->shrlen : (s)->u.lnglen)
351 
352 /* get string length from 'TValue *o' */
353 #define vslen(o)	tsslen(tsvalue(o))
354 
355 
356 /*
357 ** Header for userdata; memory area follows the end of this structure
358 ** (aligned according to 'UUdata'; see next).
359 */
360 typedef struct Udata {
361   CommonHeader;
362   lu_byte ttuv_;  /* user value's tag */
363   struct Table *metatable;
364   size_t len;  /* number of bytes */
365   union Value user_;  /* user value */
366 } Udata;
367 
368 
369 /*
370 ** Ensures that address after this type is always fully aligned.
371 */
372 typedef union UUdata {
373   L_Umaxalign dummy;  /* ensures maximum alignment for 'local' udata */
374   Udata uv;
375 } UUdata;
376 
377 
378 /*
379 **  Get the address of memory block inside 'Udata'.
380 ** (Access to 'ttuv_' ensures that value is really a 'Udata'.)
381 */
382 #define getudatamem(u)  \
383   check_exp(sizeof((u)->ttuv_), (cast(char*, (u)) + sizeof(UUdata)))
384 
385 #define setuservalue(L,u,o) \
386 	{ const TValue *io=(o); Udata *iu = (u); \
387 	  iu->user_ = io->value_; iu->ttuv_ = rttype(io); \
388 	  checkliveness(L,io); }
389 
390 
391 #define getuservalue(L,u,o) \
392 	{ TValue *io=(o); const Udata *iu = (u); \
393 	  io->value_ = iu->user_; settt_(io, iu->ttuv_); \
394 	  checkliveness(L,io); }
395 
396 
397 /*
398 ** Description of an upvalue for function prototypes
399 */
400 typedef struct Upvaldesc {
401   TString *name;  /* upvalue name (for debug information) */
402   lu_byte instack;  /* whether it is in stack (register) */
403   lu_byte idx;  /* index of upvalue (in stack or in outer function's list) */
404 } Upvaldesc;
405 
406 
407 /*
408 ** Description of a local variable for function prototypes
409 ** (used for debug information)
410 */
411 typedef struct LocVar {
412   TString *varname;
413   int startpc;  /* first point where variable is active */
414   int endpc;    /* first point where variable is dead */
415 } LocVar;
416 
417 
418 /*
419 ** Function Prototypes
420 */
421 typedef struct Proto {
422   CommonHeader;
423   lu_byte numparams;  /* number of fixed parameters */
424   lu_byte is_vararg;
425   lu_byte maxstacksize;  /* number of registers needed by this function */
426   int sizeupvalues;  /* size of 'upvalues' */
427   int sizek;  /* size of 'k' */
428   int sizecode;
429   int sizelineinfo;
430   int sizep;  /* size of 'p' */
431   int sizelocvars;
432   int linedefined;  /* debug information  */
433   int lastlinedefined;  /* debug information  */
434   TValue *k;  /* constants used by the function */
435   Instruction *code;  /* opcodes */
436   struct Proto **p;  /* functions defined inside the function */
437   int *lineinfo;  /* map from opcodes to source lines (debug information) */
438   LocVar *locvars;  /* information about local variables (debug information) */
439   Upvaldesc *upvalues;  /* upvalue information */
440   struct LClosure *cache;  /* last-created closure with this prototype */
441   TString  *source;  /* used for debug information */
442   GCObject *gclist;
443 } Proto;
444 
445 
446 
447 /*
448 ** Lua Upvalues
449 */
450 typedef struct UpVal UpVal;
451 
452 
453 /*
454 ** Closures
455 */
456 
457 #define ClosureHeader \
458 	CommonHeader; lu_byte nupvalues; GCObject *gclist
459 
460 typedef struct CClosure {
461   ClosureHeader;
462   lua_CFunction f;
463   TValue upvalue[1];  /* list of upvalues */
464 } CClosure;
465 
466 
467 typedef struct LClosure {
468   ClosureHeader;
469   struct Proto *p;
470   UpVal *upvals[1];  /* list of upvalues */
471 } LClosure;
472 
473 
474 typedef union Closure {
475   CClosure c;
476   LClosure l;
477 } Closure;
478 
479 
480 #define isLfunction(o)	ttisLclosure(o)
481 
482 #define getproto(o)	(clLvalue(o)->p)
483 
484 
485 /*
486 ** Tables
487 */
488 
489 typedef union TKey {
490   struct {
491     TValuefields;
492     int next;  /* for chaining (offset for next node) */
493   } nk;
494   TValue tvk;
495 } TKey;
496 
497 
498 /* copy a value into a key without messing up field 'next' */
499 #define setnodekey(L,key,obj) \
500 	{ TKey *k_=(key); const TValue *io_=(obj); \
501 	  k_->nk.value_ = io_->value_; k_->nk.tt_ = io_->tt_; \
502 	  (void)L; checkliveness(L,io_); }
503 
504 
505 typedef struct Node {
506   TValue i_val;
507   TKey i_key;
508 } Node;
509 
510 
511 typedef struct Table {
512   CommonHeader;
513   lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
514   lu_byte lsizenode;  /* log2 of size of 'node' array */
515   unsigned int sizearray;  /* size of 'array' array */
516   TValue *array;  /* array part */
517   Node *node;
518   Node *lastfree;  /* any free position is before this position */
519   struct Table *metatable;
520   GCObject *gclist;
521 } Table;
522 
523 
524 
525 /*
526 ** 'module' operation for hashing (size is always a power of 2)
527 */
528 #define lmod(s,size) \
529 	(check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1)))))
530 
531 
532 #define twoto(x)	(1<<(x))
533 #define sizenode(t)	(twoto((t)->lsizenode))
534 
535 
536 /*
537 ** (address of) a fixed nil value
538 */
539 #define luaO_nilobject		(&luaO_nilobject_)
540 
541 
542 LUAI_DDEC const TValue luaO_nilobject_;
543 
544 /* size of buffer for 'luaO_utf8esc' function */
545 #define UTF8BUFFSZ	8
546 
547 LUAI_FUNC int luaO_int2fb (unsigned int x);
548 LUAI_FUNC int luaO_fb2int (int x);
549 LUAI_FUNC int luaO_utf8esc (char *buff, unsigned long x);
550 LUAI_FUNC int luaO_ceillog2 (unsigned int x);
551 LUAI_FUNC void luaO_arith (lua_State *L, int op, const TValue *p1,
552                            const TValue *p2, TValue *res);
553 LUAI_FUNC size_t luaO_str2num (const char *s, TValue *o);
554 LUAI_FUNC int luaO_hexavalue (int c);
555 LUAI_FUNC void luaO_tostring (lua_State *L, StkId obj);
556 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
557                                                        va_list argp);
558 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
559 LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);
560 
561 
562 #endif
563 
564