xref: /freebsd/sys/contrib/openzfs/module/lua/lobject.h (revision 924226fba12cc9a228c73b956e1b7fa24c60b055)
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 union TString {
408   L_Umaxalign dummy;  /* ensures maximum alignment for strings */
409   struct {
410     CommonHeader;
411     lu_byte extra;  /* reserved words for short strings; "has hash" for longs */
412     unsigned int hash;
413     size_t len;  /* number of characters in string */
414   } tsv;
415 } TString;
416 
417 
418 /* get the actual string (array of bytes) from a TString */
419 #define getstr(ts)	cast(const char *, (ts) + 1)
420 
421 /* get the actual string (array of bytes) from a Lua value */
422 #define svalue(o)       getstr(rawtsvalue(o))
423 
424 
425 /*
426 ** Header for userdata; memory area follows the end of this structure
427 */
428 typedef union Udata {
429   L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */
430   struct {
431     CommonHeader;
432     struct Table *metatable;
433     struct Table *env;
434     size_t len;  /* number of bytes */
435   } uv;
436 } Udata;
437 
438 
439 
440 /*
441 ** Description of an upvalue for function prototypes
442 */
443 typedef struct Upvaldesc {
444   TString *name;  /* upvalue name (for debug information) */
445   lu_byte instack;  /* whether it is in stack */
446   lu_byte idx;  /* index of upvalue (in stack or in outer function's list) */
447 } Upvaldesc;
448 
449 
450 /*
451 ** Description of a local variable for function prototypes
452 ** (used for debug information)
453 */
454 typedef struct LocVar {
455   TString *varname;
456   int startpc;  /* first point where variable is active */
457   int endpc;    /* first point where variable is dead */
458 } LocVar;
459 
460 
461 /*
462 ** Function Prototypes
463 */
464 typedef struct Proto {
465   CommonHeader;
466   TValue *k;  /* constants used by the function */
467   Instruction *code;
468   struct Proto **p;  /* functions defined inside the function */
469   int *lineinfo;  /* map from opcodes to source lines (debug information) */
470   LocVar *locvars;  /* information about local variables (debug information) */
471   Upvaldesc *upvalues;  /* upvalue information */
472   union Closure *cache;  /* last created closure with this prototype */
473   TString  *source;  /* used for debug information */
474   int sizeupvalues;  /* size of 'upvalues' */
475   int sizek;  /* size of `k' */
476   int sizecode;
477   int sizelineinfo;
478   int sizep;  /* size of `p' */
479   int sizelocvars;
480   int linedefined;
481   int lastlinedefined;
482   GCObject *gclist;
483   lu_byte numparams;  /* number of fixed parameters */
484   lu_byte is_vararg;
485   lu_byte maxstacksize;  /* maximum stack used by this function */
486 } Proto;
487 
488 
489 
490 /*
491 ** Lua Upvalues
492 */
493 typedef struct UpVal {
494   CommonHeader;
495   TValue *v;  /* points to stack or to its own value */
496   union {
497     TValue value;  /* the value (when closed) */
498     struct {  /* double linked list (when open) */
499       struct UpVal *prev;
500       struct UpVal *next;
501     } l;
502   } u;
503 } UpVal;
504 
505 
506 /*
507 ** Closures
508 */
509 
510 #define ClosureHeader \
511 	CommonHeader; lu_byte nupvalues; GCObject *gclist
512 
513 typedef struct CClosure {
514   ClosureHeader;
515   lua_CFunction f;
516   TValue upvalue[1];  /* list of upvalues */
517 } CClosure;
518 
519 
520 typedef struct LClosure {
521   ClosureHeader;
522   struct Proto *p;
523   UpVal *upvals[1];  /* list of upvalues */
524 } LClosure;
525 
526 
527 typedef union Closure {
528   CClosure c;
529   LClosure l;
530 } Closure;
531 
532 
533 #define isLfunction(o)	ttisLclosure(o)
534 
535 #define getproto(o)	(clLvalue(o)->p)
536 
537 
538 /*
539 ** Tables
540 */
541 
542 typedef union TKey {
543   struct {
544     TValuefields;
545     struct Node *next;  /* for chaining */
546   } nk;
547   TValue tvk;
548 } TKey;
549 
550 
551 typedef struct Node {
552   TValue i_val;
553   TKey i_key;
554 } Node;
555 
556 
557 typedef struct Table {
558   CommonHeader;
559   lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
560   lu_byte lsizenode;  /* log2 of size of `node' array */
561   int sizearray;  /* size of `array' array */
562   TValue *array;  /* array part */
563   Node *node;
564   Node *lastfree;  /* any free position is before this position */
565   struct Table *metatable;
566   GCObject *gclist;
567 } Table;
568 
569 
570 
571 /*
572 ** `module' operation for hashing (size is always a power of 2)
573 */
574 #define lmod(s,size) \
575 	(check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1)))))
576 
577 
578 #define twoto(x)	(1<<(x))
579 #define sizenode(t)	(twoto((t)->lsizenode))
580 
581 
582 /*
583 ** (address of) a fixed nil value
584 */
585 #define luaO_nilobject		(&luaO_nilobject_)
586 
587 
588 LUAI_DDEC const TValue luaO_nilobject_;
589 
590 
591 LUAI_FUNC int luaO_int2fb (unsigned int x);
592 LUAI_FUNC int luaO_fb2int (int x);
593 LUAI_FUNC int luaO_ceillog2 (unsigned int x);
594 LUAI_FUNC lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2);
595 LUAI_FUNC int luaO_str2d (const char *s, size_t len, lua_Number *result);
596 LUAI_FUNC int luaO_hexavalue (int c);
597 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
598                                                        va_list argp);
599 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
600 LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);
601 
602 
603 #endif
604