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