1/*
2** $Id: lauxlib.c,v 1.248.1.1 2013/04/12 18:48:47 roberto Exp $
3** Auxiliary functions for building Lua libraries
4** See Copyright Notice in lua.h
5*/
6
7
8/* This file uses only the official API of Lua.
9** Any function declared here could be written as an application function.
10*/
11
12#define lauxlib_c
13#define LUA_LIB
14
15#include <sys/lua/lua.h>
16
17#include <sys/lua/lauxlib.h>
18
19
20/*
21** {======================================================
22** Traceback
23** =======================================================
24*/
25
26
27#define LEVELS1	12	/* size of the first part of the stack */
28#define LEVELS2	10	/* size of the second part of the stack */
29
30
31
32/*
33** search for 'objidx' in table at index -1.
34** return 1 + string at top if find a good name.
35*/
36static int findfield (lua_State *L, int objidx, int level) {
37  if (level == 0 || !lua_istable(L, -1))
38    return 0;  /* not found */
39  lua_pushnil(L);  /* start 'next' loop */
40  while (lua_next(L, -2)) {  /* for each pair in table */
41    if (lua_type(L, -2) == LUA_TSTRING) {  /* ignore non-string keys */
42      if (lua_rawequal(L, objidx, -1)) {  /* found object? */
43        lua_pop(L, 1);  /* remove value (but keep name) */
44        return 1;
45      }
46      else if (findfield(L, objidx, level - 1)) {  /* try recursively */
47        lua_remove(L, -2);  /* remove table (but keep name) */
48        lua_pushliteral(L, ".");
49        lua_insert(L, -2);  /* place '.' between the two names */
50        lua_concat(L, 3);
51        return 1;
52      }
53    }
54    lua_pop(L, 1);  /* remove value */
55  }
56  return 0;  /* not found */
57}
58
59
60static int pushglobalfuncname (lua_State *L, lua_Debug *ar) {
61  int top = lua_gettop(L);
62  lua_getinfo(L, "f", ar);  /* push function */
63  lua_pushglobaltable(L);
64  if (findfield(L, top + 1, 2)) {
65    lua_copy(L, -1, top + 1);  /* move name to proper place */
66    lua_pop(L, 2);  /* remove pushed values */
67    return 1;
68  }
69  else {
70    lua_settop(L, top);  /* remove function and global table */
71    return 0;
72  }
73}
74
75
76static void pushfuncname (lua_State *L, lua_Debug *ar) {
77  if (*ar->namewhat != '\0')  /* is there a name? */
78    lua_pushfstring(L, "function " LUA_QS, ar->name);
79  else if (*ar->what == 'm')  /* main? */
80      lua_pushliteral(L, "main chunk");
81  else if (*ar->what == 'C') {
82    if (pushglobalfuncname(L, ar)) {
83      lua_pushfstring(L, "function " LUA_QS, lua_tostring(L, -1));
84      lua_remove(L, -2);  /* remove name */
85    }
86    else
87      lua_pushliteral(L, "?");
88  }
89  else
90    lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);
91}
92
93
94static int countlevels (lua_State *L) {
95  lua_Debug ar;
96  int li = 1, le = 1;
97  /* find an upper bound */
98  while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }
99  /* do a binary search */
100  while (li < le) {
101    int m = (li + le)/2;
102    if (lua_getstack(L, m, &ar)) li = m + 1;
103    else le = m;
104  }
105  return le - 1;
106}
107
108
109LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1,
110                                const char *msg, int level) {
111  lua_Debug ar;
112  int top = lua_gettop(L);
113  int numlevels = countlevels(L1);
114  int mark = (numlevels > LEVELS1 + LEVELS2) ? LEVELS1 : 0;
115  if (msg) lua_pushfstring(L, "%s\n", msg);
116  lua_pushliteral(L, "stack traceback:");
117  while (lua_getstack(L1, level++, &ar)) {
118    if (level == mark) {  /* too many levels? */
119      lua_pushliteral(L, "\n\t...");  /* add a '...' */
120      level = numlevels - LEVELS2;  /* and skip to last ones */
121    }
122    else {
123      lua_getinfo(L1, "Slnt", &ar);
124      lua_pushfstring(L, "\n\t%s:", ar.short_src);
125      if (ar.currentline > 0)
126        lua_pushfstring(L, "%d:", ar.currentline);
127      lua_pushliteral(L, " in ");
128      pushfuncname(L, &ar);
129      if (ar.istailcall)
130        lua_pushliteral(L, "\n\t(...tail calls...)");
131      lua_concat(L, lua_gettop(L) - top);
132    }
133  }
134  lua_concat(L, lua_gettop(L) - top);
135}
136
137/* }====================================================== */
138
139
140/*
141** {======================================================
142** Error-report functions
143** =======================================================
144*/
145
146LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
147  lua_Debug ar;
148  if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
149    return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
150  lua_getinfo(L, "n", &ar);
151  if (strcmp(ar.namewhat, "method") == 0) {
152    narg--;  /* do not count `self' */
153    if (narg == 0)  /* error is in the self argument itself? */
154      return luaL_error(L, "calling " LUA_QS " on bad self (%s)",
155                           ar.name, extramsg);
156  }
157  if (ar.name == NULL)
158    ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?";
159  return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
160                        narg, ar.name, extramsg);
161}
162
163
164static int typeerror (lua_State *L, int narg, const char *tname) {
165  const char *msg = lua_pushfstring(L, "%s expected, got %s",
166                                    tname, luaL_typename(L, narg));
167  return luaL_argerror(L, narg, msg);
168}
169
170
171static void tag_error (lua_State *L, int narg, int tag) {
172  typeerror(L, narg, lua_typename(L, tag));
173}
174
175
176LUALIB_API void luaL_where (lua_State *L, int level) {
177  lua_Debug ar;
178  if (lua_getstack(L, level, &ar)) {  /* check function at level */
179    lua_getinfo(L, "Sl", &ar);  /* get info about it */
180    if (ar.currentline > 0) {  /* is there info? */
181      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
182      return;
183    }
184  }
185  lua_pushliteral(L, "");  /* else, no information available... */
186}
187
188
189LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
190  va_list argp;
191  va_start(argp, fmt);
192  luaL_where(L, 1);
193  lua_pushvfstring(L, fmt, argp);
194  va_end(argp);
195  lua_concat(L, 2);
196  return lua_error(L);
197}
198
199
200#if !defined(inspectstat)	/* { */
201
202#if defined(LUA_USE_POSIX)
203
204#include <sys/wait.h>
205
206/*
207** use appropriate macros to interpret 'pclose' return status
208*/
209#define inspectstat(stat,what)  \
210   if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
211   else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
212
213#else
214
215#define inspectstat(stat,what)  /* no op */
216
217#endif
218
219#endif				/* } */
220
221
222/* }====================================================== */
223
224
225/*
226** {======================================================
227** Userdata's metatable manipulation
228** =======================================================
229*/
230
231LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
232  luaL_getmetatable(L, tname);  /* try to get metatable */
233  if (!lua_isnil(L, -1))  /* name already in use? */
234    return 0;  /* leave previous value on top, but return 0 */
235  lua_pop(L, 1);
236  lua_newtable(L);  /* create metatable */
237  lua_pushvalue(L, -1);
238  lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
239  return 1;
240}
241
242
243LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) {
244  luaL_getmetatable(L, tname);
245  lua_setmetatable(L, -2);
246}
247
248
249LUALIB_API void *luaL_testudata (lua_State *L, int ud, const char *tname) {
250  void *p = lua_touserdata(L, ud);
251  if (p != NULL) {  /* value is a userdata? */
252    if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
253      luaL_getmetatable(L, tname);  /* get correct metatable */
254      if (!lua_rawequal(L, -1, -2))  /* not the same? */
255        p = NULL;  /* value is a userdata with wrong metatable */
256      lua_pop(L, 2);  /* remove both metatables */
257      return p;
258    }
259  }
260  return NULL;  /* value is not a userdata with a metatable */
261}
262
263
264LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
265  void *p = luaL_testudata(L, ud, tname);
266  if (p == NULL) typeerror(L, ud, tname);
267  return p;
268}
269
270/* }====================================================== */
271
272
273/*
274** {======================================================
275** Argument check functions
276** =======================================================
277*/
278
279LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def,
280                                 const char *const lst[]) {
281  const char *name = (def) ? luaL_optstring(L, narg, def) :
282                             luaL_checkstring(L, narg);
283  int i;
284  for (i=0; lst[i]; i++)
285    if (strcmp(lst[i], name) == 0)
286      return i;
287  return luaL_argerror(L, narg,
288                       lua_pushfstring(L, "invalid option " LUA_QS, name));
289}
290
291
292LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) {
293  /* keep some extra space to run error routines, if needed */
294  const int extra = LUA_MINSTACK;
295  if (!lua_checkstack(L, space + extra)) {
296    if (msg)
297      luaL_error(L, "stack overflow (%s)", msg);
298    else
299      luaL_error(L, "stack overflow");
300  }
301}
302
303
304LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
305  if (lua_type(L, narg) != t)
306    tag_error(L, narg, t);
307}
308
309
310LUALIB_API void luaL_checkany (lua_State *L, int narg) {
311  if (lua_type(L, narg) == LUA_TNONE)
312    luaL_argerror(L, narg, "value expected");
313}
314
315
316LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
317  const char *s = lua_tolstring(L, narg, len);
318  if (!s) tag_error(L, narg, LUA_TSTRING);
319  return s;
320}
321
322
323LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
324                                        const char *def, size_t *len) {
325  if (lua_isnoneornil(L, narg)) {
326    if (len)
327      *len = (def ? strlen(def) : 0);
328    return def;
329  }
330  else return luaL_checklstring(L, narg, len);
331}
332
333
334LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
335  int isnum;
336  lua_Number d = lua_tonumberx(L, narg, &isnum);
337  if (!isnum)
338    tag_error(L, narg, LUA_TNUMBER);
339  return d;
340}
341
342
343LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
344  return luaL_opt(L, luaL_checknumber, narg, def);
345}
346
347
348LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
349  int isnum;
350  lua_Integer d = lua_tointegerx(L, narg, &isnum);
351  if (!isnum)
352    tag_error(L, narg, LUA_TNUMBER);
353  return d;
354}
355
356
357LUALIB_API lua_Unsigned luaL_checkunsigned (lua_State *L, int narg) {
358  int isnum;
359  lua_Unsigned d = lua_tounsignedx(L, narg, &isnum);
360  if (!isnum)
361    tag_error(L, narg, LUA_TNUMBER);
362  return d;
363}
364
365
366LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
367                                                      lua_Integer def) {
368  return luaL_opt(L, luaL_checkinteger, narg, def);
369}
370
371
372LUALIB_API lua_Unsigned luaL_optunsigned (lua_State *L, int narg,
373                                                        lua_Unsigned def) {
374  return luaL_opt(L, luaL_checkunsigned, narg, def);
375}
376
377/* }====================================================== */
378
379
380/*
381** {======================================================
382** Generic Buffer manipulation
383** =======================================================
384*/
385
386/*
387** check whether buffer is using a userdata on the stack as a temporary
388** buffer
389*/
390#define buffonstack(B)	((B)->b != (B)->initb)
391
392
393/*
394** returns a pointer to a free area with at least 'sz' bytes
395*/
396LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) {
397  lua_State *L = B->L;
398  if (B->size - B->n < sz) {  /* not enough space? */
399    char *newbuff;
400    size_t newsize = B->size * 2;  /* double buffer size */
401    if (newsize - B->n < sz)  /* not big enough? */
402      newsize = B->n + sz;
403    if (newsize < B->n || newsize - B->n < sz)
404      luaL_error(L, "buffer too large");
405    /* create larger buffer */
406    newbuff = (char *)lua_newuserdata(L, newsize * sizeof(char));
407    /* move content to new buffer */
408    memcpy(newbuff, B->b, B->n * sizeof(char));
409    if (buffonstack(B))
410      lua_remove(L, -2);  /* remove old buffer */
411    B->b = newbuff;
412    B->size = newsize;
413  }
414  return &B->b[B->n];
415}
416
417
418LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
419  char *b = luaL_prepbuffsize(B, l);
420  memcpy(b, s, l * sizeof(char));
421  luaL_addsize(B, l);
422}
423
424
425LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
426  luaL_addlstring(B, s, strlen(s));
427}
428
429
430LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
431  lua_State *L = B->L;
432  lua_pushlstring(L, B->b, B->n);
433  if (buffonstack(B))
434    lua_remove(L, -2);  /* remove old buffer */
435}
436
437
438LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) {
439  luaL_addsize(B, sz);
440  luaL_pushresult(B);
441}
442
443
444LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
445  lua_State *L = B->L;
446  size_t l;
447  const char *s = lua_tolstring(L, -1, &l);
448  if (buffonstack(B))
449    lua_insert(L, -2);  /* put value below buffer */
450  luaL_addlstring(B, s, l);
451  lua_remove(L, (buffonstack(B)) ? -2 : -1);  /* remove value */
452}
453
454
455LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
456  B->L = L;
457  B->b = B->initb;
458  B->n = 0;
459  B->size = LUAL_BUFFERSIZE;
460}
461
462
463LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) {
464  luaL_buffinit(L, B);
465  return luaL_prepbuffsize(B, sz);
466}
467
468/* }====================================================== */
469
470
471/*
472** {======================================================
473** Reference system
474** =======================================================
475*/
476
477/* index of free-list header */
478#define freelist	0
479
480
481LUALIB_API int luaL_ref (lua_State *L, int t) {
482  int ref;
483  if (lua_isnil(L, -1)) {
484    lua_pop(L, 1);  /* remove from stack */
485    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
486  }
487  t = lua_absindex(L, t);
488  lua_rawgeti(L, t, freelist);  /* get first free element */
489  ref = (int)lua_tointeger(L, -1);  /* ref = t[freelist] */
490  lua_pop(L, 1);  /* remove it from stack */
491  if (ref != 0) {  /* any free element? */
492    lua_rawgeti(L, t, ref);  /* remove it from list */
493    lua_rawseti(L, t, freelist);  /* (t[freelist] = t[ref]) */
494  }
495  else  /* no free elements */
496    ref = (int)lua_rawlen(L, t) + 1;  /* get a new reference */
497  lua_rawseti(L, t, ref);
498  return ref;
499}
500
501
502LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
503  if (ref >= 0) {
504    t = lua_absindex(L, t);
505    lua_rawgeti(L, t, freelist);
506    lua_rawseti(L, t, ref);  /* t[ref] = t[freelist] */
507    lua_pushinteger(L, ref);
508    lua_rawseti(L, t, freelist);  /* t[freelist] = ref */
509  }
510}
511
512/* }====================================================== */
513
514
515/*
516** {======================================================
517** Load functions
518** =======================================================
519*/
520
521typedef struct LoadS {
522  const char *s;
523  size_t size;
524} LoadS;
525
526
527static const char *getS (lua_State *L, void *ud, size_t *size) {
528  LoadS *ls = (LoadS *)ud;
529  (void)L;  /* not used */
530  if (ls->size == 0) return NULL;
531  *size = ls->size;
532  ls->size = 0;
533  return ls->s;
534}
535
536
537LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size,
538                                 const char *name, const char *mode) {
539  LoadS ls;
540  ls.s = buff;
541  ls.size = size;
542  return lua_load(L, getS, &ls, name, mode);
543}
544
545
546LUALIB_API int luaL_loadstring (lua_State *L, const char *s) {
547  return luaL_loadbuffer(L, s, strlen(s), s);
548}
549
550/* }====================================================== */
551
552
553
554LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
555  if (!lua_getmetatable(L, obj))  /* no metatable? */
556    return 0;
557  lua_pushstring(L, event);
558  lua_rawget(L, -2);
559  if (lua_isnil(L, -1)) {
560    lua_pop(L, 2);  /* remove metatable and metafield */
561    return 0;
562  }
563  else {
564    lua_remove(L, -2);  /* remove only metatable */
565    return 1;
566  }
567}
568
569
570LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
571  obj = lua_absindex(L, obj);
572  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
573    return 0;
574  lua_pushvalue(L, obj);
575  lua_call(L, 1, 1);
576  return 1;
577}
578
579
580LUALIB_API int luaL_len (lua_State *L, int idx) {
581  int l;
582  int isnum;
583  lua_len(L, idx);
584  l = (int)lua_tointegerx(L, -1, &isnum);
585  if (!isnum)
586    luaL_error(L, "object length is not a number");
587  lua_pop(L, 1);  /* remove object */
588  return l;
589}
590
591
592LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
593  if (!luaL_callmeta(L, idx, "__tostring")) {  /* no metafield? */
594    switch (lua_type(L, idx)) {
595      case LUA_TNUMBER:
596      case LUA_TSTRING:
597        lua_pushvalue(L, idx);
598        break;
599      case LUA_TBOOLEAN:
600        lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false"));
601        break;
602      case LUA_TNIL:
603        lua_pushliteral(L, "nil");
604        break;
605      default:
606        lua_pushfstring(L, "%s: %p", luaL_typename(L, idx),
607                                            lua_topointer(L, idx));
608        break;
609    }
610  }
611  return lua_tolstring(L, -1, len);
612}
613
614
615/*
616** {======================================================
617** Compatibility with 5.1 module functions
618** =======================================================
619*/
620#if defined(LUA_COMPAT_MODULE)
621
622static const char *luaL_findtable (lua_State *L, int idx,
623                                   const char *fname, int szhint) {
624  const char *e;
625  if (idx) lua_pushvalue(L, idx);
626  do {
627    e = strchr(fname, '.');
628    if (e == NULL) e = fname + strlen(fname);
629    lua_pushlstring(L, fname, e - fname);
630    lua_rawget(L, -2);
631    if (lua_isnil(L, -1)) {  /* no such field? */
632      lua_pop(L, 1);  /* remove this nil */
633      lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
634      lua_pushlstring(L, fname, e - fname);
635      lua_pushvalue(L, -2);
636      lua_settable(L, -4);  /* set new table into field */
637    }
638    else if (!lua_istable(L, -1)) {  /* field has a non-table value? */
639      lua_pop(L, 2);  /* remove table and value */
640      return fname;  /* return problematic part of the name */
641    }
642    lua_remove(L, -2);  /* remove previous table */
643    fname = e + 1;
644  } while (*e == '.');
645  return NULL;
646}
647
648
649/*
650** Count number of elements in a luaL_Reg list.
651*/
652static int libsize (const luaL_Reg *l) {
653  int size = 0;
654  for (; l && l->name; l++) size++;
655  return size;
656}
657
658
659/*
660** Find or create a module table with a given name. The function
661** first looks at the _LOADED table and, if that fails, try a
662** global variable with that name. In any case, leaves on the stack
663** the module table.
664*/
665LUALIB_API void luaL_pushmodule (lua_State *L, const char *modname,
666                                 int sizehint) {
667  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);  /* get _LOADED table */
668  lua_getfield(L, -1, modname);  /* get _LOADED[modname] */
669  if (!lua_istable(L, -1)) {  /* not found? */
670    lua_pop(L, 1);  /* remove previous result */
671    /* try global variable (and create one if it does not exist) */
672    lua_pushglobaltable(L);
673    if (luaL_findtable(L, 0, modname, sizehint) != NULL)
674      luaL_error(L, "name conflict for module " LUA_QS, modname);
675    lua_pushvalue(L, -1);
676    lua_setfield(L, -3, modname);  /* _LOADED[modname] = new table */
677  }
678  lua_remove(L, -2);  /* remove _LOADED table */
679}
680
681
682LUALIB_API void luaL_openlib (lua_State *L, const char *libname,
683                               const luaL_Reg *l, int nup) {
684  luaL_checkversion(L);
685  if (libname) {
686    luaL_pushmodule(L, libname, libsize(l));  /* get/create library table */
687    lua_insert(L, -(nup + 1));  /* move library table to below upvalues */
688  }
689  if (l)
690    luaL_setfuncs(L, l, nup);
691  else
692    lua_pop(L, nup);  /* remove upvalues */
693}
694
695#endif
696/* }====================================================== */
697
698/*
699** set functions from list 'l' into table at top - 'nup'; each
700** function gets the 'nup' elements at the top as upvalues.
701** Returns with only the table at the stack.
702*/
703LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
704  luaL_checkversion(L);
705  luaL_checkstack(L, nup, "too many upvalues");
706  for (; l->name != NULL; l++) {  /* fill the table with given functions */
707    int i;
708    for (i = 0; i < nup; i++)  /* copy upvalues to the top */
709      lua_pushvalue(L, -nup);
710    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
711    lua_setfield(L, -(nup + 2), l->name);
712  }
713  lua_pop(L, nup);  /* remove upvalues */
714}
715
716
717/*
718** ensure that stack[idx][fname] has a table and push that table
719** into the stack
720*/
721LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) {
722  lua_getfield(L, idx, fname);
723  if (lua_istable(L, -1)) return 1;  /* table already there */
724  else {
725    lua_pop(L, 1);  /* remove previous result */
726    idx = lua_absindex(L, idx);
727    lua_newtable(L);
728    lua_pushvalue(L, -1);  /* copy to be left at top */
729    lua_setfield(L, idx, fname);  /* assign new table to field */
730    return 0;  /* false, because did not find table there */
731  }
732}
733
734
735/*
736** stripped-down 'require'. Calls 'openf' to open a module,
737** registers the result in 'package.loaded' table and, if 'glb'
738** is true, also registers the result in the global table.
739** Leaves resulting module on the top.
740*/
741LUALIB_API void luaL_requiref (lua_State *L, const char *modname,
742                               lua_CFunction openf, int glb) {
743  lua_pushcfunction(L, openf);
744  lua_pushstring(L, modname);  /* argument to open function */
745  lua_call(L, 1, 1);  /* open module */
746  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED");
747  lua_pushvalue(L, -2);  /* make copy of module (call result) */
748  lua_setfield(L, -2, modname);  /* _LOADED[modname] = module */
749  lua_pop(L, 1);  /* remove _LOADED table */
750  if (glb) {
751    lua_pushvalue(L, -1);  /* copy of 'mod' */
752    lua_setglobal(L, modname);  /* _G[modname] = module */
753  }
754}
755
756
757LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
758                                                               const char *r) {
759  const char *wild;
760  size_t l = strlen(p);
761  luaL_Buffer b;
762  luaL_buffinit(L, &b);
763  while ((wild = strstr(s, p)) != NULL) {
764    luaL_addlstring(&b, s, wild - s);  /* push prefix */
765    luaL_addstring(&b, r);  /* push replacement in place of pattern */
766    s = wild + l;  /* continue after `p' */
767  }
768  luaL_addstring(&b, s);  /* push last suffix */
769  luaL_pushresult(&b);
770  return lua_tostring(L, -1);
771}
772
773
774LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver) {
775  const lua_Number *v = lua_version(L);
776  if (v != lua_version(NULL))
777    luaL_error(L, "multiple Lua VMs detected");
778  else if (*v != ver)
779    luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f",
780                  ver, *v);
781  /* check conversions number -> integer types */
782  lua_pushnumber(L, -(lua_Number)0x1234);
783  if (lua_tointeger(L, -1) != -0x1234 ||
784      lua_tounsigned(L, -1) != (lua_Unsigned)-0x1234)
785    luaL_error(L, "bad conversion number->int;"
786                  " must recompile Lua with proper settings");
787  lua_pop(L, 1);
788}
789
790#if defined(_KERNEL)
791
792EXPORT_SYMBOL(luaL_argerror);
793EXPORT_SYMBOL(luaL_error);
794EXPORT_SYMBOL(luaL_loadbufferx);
795EXPORT_SYMBOL(luaL_newmetatable);
796EXPORT_SYMBOL(luaL_traceback);
797
798#endif
799