1/* BEGIN CSTYLED */
2/*
3** $Id: lauxlib.c,v 1.248.1.1 2013/04/12 18:48:47 roberto Exp $
4** Auxiliary functions for building Lua libraries
5** See Copyright Notice in lua.h
6*/
7
8
9/* This file uses only the official API of Lua.
10** Any function declared here could be written as an application function.
11*/
12
13#define lauxlib_c
14#define LUA_LIB
15
16#include <sys/lua/lua.h>
17
18#include <sys/lua/lauxlib.h>
19
20
21/*
22** {======================================================
23** Traceback
24** =======================================================
25*/
26
27
28#define LEVELS1	12	/* size of the first part of the stack */
29#define LEVELS2	10	/* size of the second part of the stack */
30
31
32
33/*
34** search for 'objidx' in table at index -1.
35** return 1 + string at top if find a good name.
36*/
37static int findfield (lua_State *L, int objidx, int level) {
38  if (level == 0 || !lua_istable(L, -1))
39    return 0;  /* not found */
40  lua_pushnil(L);  /* start 'next' loop */
41  while (lua_next(L, -2)) {  /* for each pair in table */
42    if (lua_type(L, -2) == LUA_TSTRING) {  /* ignore non-string keys */
43      if (lua_rawequal(L, objidx, -1)) {  /* found object? */
44        lua_pop(L, 1);  /* remove value (but keep name) */
45        return 1;
46      }
47      else if (findfield(L, objidx, level - 1)) {  /* try recursively */
48        lua_remove(L, -2);  /* remove table (but keep name) */
49        lua_pushliteral(L, ".");
50        lua_insert(L, -2);  /* place '.' between the two names */
51        lua_concat(L, 3);
52        return 1;
53      }
54    }
55    lua_pop(L, 1);  /* remove value */
56  }
57  return 0;  /* not found */
58}
59
60
61static int pushglobalfuncname (lua_State *L, lua_Debug *ar) {
62  int top = lua_gettop(L);
63  lua_getinfo(L, "f", ar);  /* push function */
64  lua_pushglobaltable(L);
65  if (findfield(L, top + 1, 2)) {
66    lua_copy(L, -1, top + 1);  /* move name to proper place */
67    lua_pop(L, 2);  /* remove pushed values */
68    return 1;
69  }
70  else {
71    lua_settop(L, top);  /* remove function and global table */
72    return 0;
73  }
74}
75
76
77static void pushfuncname (lua_State *L, lua_Debug *ar) {
78  if (*ar->namewhat != '\0')  /* is there a name? */
79    lua_pushfstring(L, "function " LUA_QS, ar->name);
80  else if (*ar->what == 'm')  /* main? */
81      lua_pushliteral(L, "main chunk");
82  else if (*ar->what == 'C') {
83    if (pushglobalfuncname(L, ar)) {
84      lua_pushfstring(L, "function " LUA_QS, lua_tostring(L, -1));
85      lua_remove(L, -2);  /* remove name */
86    }
87    else
88      lua_pushliteral(L, "?");
89  }
90  else
91    lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);
92}
93
94
95static int countlevels (lua_State *L) {
96  lua_Debug ar;
97  int li = 1, le = 1;
98  /* find an upper bound */
99  while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }
100  /* do a binary search */
101  while (li < le) {
102    int m = (li + le)/2;
103    if (lua_getstack(L, m, &ar)) li = m + 1;
104    else le = m;
105  }
106  return le - 1;
107}
108
109
110LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1,
111                                const char *msg, int level) {
112  lua_Debug ar;
113  int top = lua_gettop(L);
114  int numlevels = countlevels(L1);
115  int mark = (numlevels > LEVELS1 + LEVELS2) ? LEVELS1 : 0;
116  if (msg) lua_pushfstring(L, "%s\n", msg);
117  lua_pushliteral(L, "stack traceback:");
118  while (lua_getstack(L1, level++, &ar)) {
119    if (level == mark) {  /* too many levels? */
120      lua_pushliteral(L, "\n\t...");  /* add a '...' */
121      level = numlevels - LEVELS2;  /* and skip to last ones */
122    }
123    else {
124      lua_getinfo(L1, "Slnt", &ar);
125      lua_pushfstring(L, "\n\t%s:", ar.short_src);
126      if (ar.currentline > 0)
127        lua_pushfstring(L, "%d:", ar.currentline);
128      lua_pushliteral(L, " in ");
129      pushfuncname(L, &ar);
130      if (ar.istailcall)
131        lua_pushliteral(L, "\n\t(...tail calls...)");
132      lua_concat(L, lua_gettop(L) - top);
133    }
134  }
135  lua_concat(L, lua_gettop(L) - top);
136}
137
138/* }====================================================== */
139
140
141/*
142** {======================================================
143** Error-report functions
144** =======================================================
145*/
146
147LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
148  lua_Debug ar;
149  if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
150    return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
151  lua_getinfo(L, "n", &ar);
152  if (strcmp(ar.namewhat, "method") == 0) {
153    narg--;  /* do not count `self' */
154    if (narg == 0)  /* error is in the self argument itself? */
155      return luaL_error(L, "calling " LUA_QS " on bad self (%s)",
156                           ar.name, extramsg);
157  }
158  if (ar.name == NULL)
159    ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?";
160  return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
161                        narg, ar.name, extramsg);
162}
163
164
165static int typeerror (lua_State *L, int narg, const char *tname) {
166  const char *msg = lua_pushfstring(L, "%s expected, got %s",
167                                    tname, luaL_typename(L, narg));
168  return luaL_argerror(L, narg, msg);
169}
170
171
172static void tag_error (lua_State *L, int narg, int tag) {
173  typeerror(L, narg, lua_typename(L, tag));
174}
175
176
177LUALIB_API void luaL_where (lua_State *L, int level) {
178  lua_Debug ar;
179  if (lua_getstack(L, level, &ar)) {  /* check function at level */
180    lua_getinfo(L, "Sl", &ar);  /* get info about it */
181    if (ar.currentline > 0) {  /* is there info? */
182      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
183      return;
184    }
185  }
186  lua_pushliteral(L, "");  /* else, no information available... */
187}
188
189
190LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
191  va_list argp;
192  va_start(argp, fmt);
193  luaL_where(L, 1);
194  lua_pushvfstring(L, fmt, argp);
195  va_end(argp);
196  lua_concat(L, 2);
197  return lua_error(L);
198}
199
200
201#if !defined(inspectstat)	/* { */
202
203#if defined(LUA_USE_POSIX)
204
205#include <sys/wait.h>
206
207/*
208** use appropriate macros to interpret 'pclose' return status
209*/
210#define inspectstat(stat,what)  \
211   if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
212   else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
213
214#else
215
216#define inspectstat(stat,what)  /* no op */
217
218#endif
219
220#endif				/* } */
221
222
223/* }====================================================== */
224
225
226/*
227** {======================================================
228** Userdata's metatable manipulation
229** =======================================================
230*/
231
232LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
233  luaL_getmetatable(L, tname);  /* try to get metatable */
234  if (!lua_isnil(L, -1))  /* name already in use? */
235    return 0;  /* leave previous value on top, but return 0 */
236  lua_pop(L, 1);
237  lua_newtable(L);  /* create metatable */
238  lua_pushvalue(L, -1);
239  lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
240  return 1;
241}
242
243
244LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) {
245  luaL_getmetatable(L, tname);
246  lua_setmetatable(L, -2);
247}
248
249
250LUALIB_API void *luaL_testudata (lua_State *L, int ud, const char *tname) {
251  void *p = lua_touserdata(L, ud);
252  if (p != NULL) {  /* value is a userdata? */
253    if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
254      luaL_getmetatable(L, tname);  /* get correct metatable */
255      if (!lua_rawequal(L, -1, -2))  /* not the same? */
256        p = NULL;  /* value is a userdata with wrong metatable */
257      lua_pop(L, 2);  /* remove both metatables */
258      return p;
259    }
260  }
261  return NULL;  /* value is not a userdata with a metatable */
262}
263
264
265LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
266  void *p = luaL_testudata(L, ud, tname);
267  if (p == NULL) typeerror(L, ud, tname);
268  return p;
269}
270
271/* }====================================================== */
272
273
274/*
275** {======================================================
276** Argument check functions
277** =======================================================
278*/
279
280LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def,
281                                 const char *const lst[]) {
282  const char *name = (def) ? luaL_optstring(L, narg, def) :
283                             luaL_checkstring(L, narg);
284  int i;
285  for (i=0; lst[i]; i++)
286    if (strcmp(lst[i], name) == 0)
287      return i;
288  return luaL_argerror(L, narg,
289                       lua_pushfstring(L, "invalid option " LUA_QS, name));
290}
291
292
293LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) {
294  /* keep some extra space to run error routines, if needed */
295  const int extra = LUA_MINSTACK;
296  if (!lua_checkstack(L, space + extra)) {
297    if (msg)
298      luaL_error(L, "stack overflow (%s)", msg);
299    else
300      luaL_error(L, "stack overflow");
301  }
302}
303
304
305LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
306  if (lua_type(L, narg) != t)
307    tag_error(L, narg, t);
308}
309
310
311LUALIB_API void luaL_checkany (lua_State *L, int narg) {
312  if (lua_type(L, narg) == LUA_TNONE)
313    luaL_argerror(L, narg, "value expected");
314}
315
316
317LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
318  const char *s = lua_tolstring(L, narg, len);
319  if (!s) tag_error(L, narg, LUA_TSTRING);
320  return s;
321}
322
323
324LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
325                                        const char *def, size_t *len) {
326  if (lua_isnoneornil(L, narg)) {
327    if (len)
328      *len = (def ? strlen(def) : 0);
329    return def;
330  }
331  else return luaL_checklstring(L, narg, len);
332}
333
334
335LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
336  int isnum;
337  lua_Number d = lua_tonumberx(L, narg, &isnum);
338  if (!isnum)
339    tag_error(L, narg, LUA_TNUMBER);
340  return d;
341}
342
343
344LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
345  return luaL_opt(L, luaL_checknumber, narg, def);
346}
347
348
349LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
350  int isnum;
351  lua_Integer d = lua_tointegerx(L, narg, &isnum);
352  if (!isnum)
353    tag_error(L, narg, LUA_TNUMBER);
354  return d;
355}
356
357
358LUALIB_API lua_Unsigned luaL_checkunsigned (lua_State *L, int narg) {
359  int isnum;
360  lua_Unsigned d = lua_tounsignedx(L, narg, &isnum);
361  if (!isnum)
362    tag_error(L, narg, LUA_TNUMBER);
363  return d;
364}
365
366
367LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
368                                                      lua_Integer def) {
369  return luaL_opt(L, luaL_checkinteger, narg, def);
370}
371
372
373LUALIB_API lua_Unsigned luaL_optunsigned (lua_State *L, int narg,
374                                                        lua_Unsigned def) {
375  return luaL_opt(L, luaL_checkunsigned, narg, def);
376}
377
378/* }====================================================== */
379
380
381/*
382** {======================================================
383** Generic Buffer manipulation
384** =======================================================
385*/
386
387/*
388** check whether buffer is using a userdata on the stack as a temporary
389** buffer
390*/
391#define buffonstack(B)	((B)->b != (B)->initb)
392
393
394/*
395** returns a pointer to a free area with at least 'sz' bytes
396*/
397LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) {
398  lua_State *L = B->L;
399  if (B->size - B->n < sz) {  /* not enough space? */
400    char *newbuff;
401    size_t newsize = B->size * 2;  /* double buffer size */
402    if (newsize - B->n < sz)  /* not big enough? */
403      newsize = B->n + sz;
404    if (newsize < B->n || newsize - B->n < sz)
405      luaL_error(L, "buffer too large");
406    /* create larger buffer */
407    newbuff = (char *)lua_newuserdata(L, newsize * sizeof(char));
408    /* move content to new buffer */
409    memcpy(newbuff, B->b, B->n * sizeof(char));
410    if (buffonstack(B))
411      lua_remove(L, -2);  /* remove old buffer */
412    B->b = newbuff;
413    B->size = newsize;
414  }
415  return &B->b[B->n];
416}
417
418
419LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
420  char *b = luaL_prepbuffsize(B, l);
421  memcpy(b, s, l * sizeof(char));
422  luaL_addsize(B, l);
423}
424
425
426LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
427  luaL_addlstring(B, s, strlen(s));
428}
429
430
431LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
432  lua_State *L = B->L;
433  lua_pushlstring(L, B->b, B->n);
434  if (buffonstack(B))
435    lua_remove(L, -2);  /* remove old buffer */
436}
437
438
439LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) {
440  luaL_addsize(B, sz);
441  luaL_pushresult(B);
442}
443
444
445LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
446  lua_State *L = B->L;
447  size_t l;
448  const char *s = lua_tolstring(L, -1, &l);
449  if (buffonstack(B))
450    lua_insert(L, -2);  /* put value below buffer */
451  luaL_addlstring(B, s, l);
452  lua_remove(L, (buffonstack(B)) ? -2 : -1);  /* remove value */
453}
454
455
456LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
457  B->L = L;
458  B->b = B->initb;
459  B->n = 0;
460  B->size = LUAL_BUFFERSIZE;
461}
462
463
464LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) {
465  luaL_buffinit(L, B);
466  return luaL_prepbuffsize(B, sz);
467}
468
469/* }====================================================== */
470
471
472/*
473** {======================================================
474** Reference system
475** =======================================================
476*/
477
478/* index of free-list header */
479#define freelist	0
480
481
482LUALIB_API int luaL_ref (lua_State *L, int t) {
483  int ref;
484  if (lua_isnil(L, -1)) {
485    lua_pop(L, 1);  /* remove from stack */
486    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
487  }
488  t = lua_absindex(L, t);
489  lua_rawgeti(L, t, freelist);  /* get first free element */
490  ref = (int)lua_tointeger(L, -1);  /* ref = t[freelist] */
491  lua_pop(L, 1);  /* remove it from stack */
492  if (ref != 0) {  /* any free element? */
493    lua_rawgeti(L, t, ref);  /* remove it from list */
494    lua_rawseti(L, t, freelist);  /* (t[freelist] = t[ref]) */
495  }
496  else  /* no free elements */
497    ref = (int)lua_rawlen(L, t) + 1;  /* get a new reference */
498  lua_rawseti(L, t, ref);
499  return ref;
500}
501
502
503LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
504  if (ref >= 0) {
505    t = lua_absindex(L, t);
506    lua_rawgeti(L, t, freelist);
507    lua_rawseti(L, t, ref);  /* t[ref] = t[freelist] */
508    lua_pushinteger(L, ref);
509    lua_rawseti(L, t, freelist);  /* t[freelist] = ref */
510  }
511}
512
513/* }====================================================== */
514
515
516/*
517** {======================================================
518** Load functions
519** =======================================================
520*/
521
522typedef struct LoadS {
523  const char *s;
524  size_t size;
525} LoadS;
526
527
528static const char *getS (lua_State *L, void *ud, size_t *size) {
529  LoadS *ls = (LoadS *)ud;
530  (void)L;  /* not used */
531  if (ls->size == 0) return NULL;
532  *size = ls->size;
533  ls->size = 0;
534  return ls->s;
535}
536
537
538LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size,
539                                 const char *name, const char *mode) {
540  LoadS ls;
541  ls.s = buff;
542  ls.size = size;
543  return lua_load(L, getS, &ls, name, mode);
544}
545
546
547LUALIB_API int luaL_loadstring (lua_State *L, const char *s) {
548  return luaL_loadbuffer(L, s, strlen(s), s);
549}
550
551/* }====================================================== */
552
553
554
555LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
556  if (!lua_getmetatable(L, obj))  /* no metatable? */
557    return 0;
558  lua_pushstring(L, event);
559  lua_rawget(L, -2);
560  if (lua_isnil(L, -1)) {
561    lua_pop(L, 2);  /* remove metatable and metafield */
562    return 0;
563  }
564  else {
565    lua_remove(L, -2);  /* remove only metatable */
566    return 1;
567  }
568}
569
570
571LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
572  obj = lua_absindex(L, obj);
573  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
574    return 0;
575  lua_pushvalue(L, obj);
576  lua_call(L, 1, 1);
577  return 1;
578}
579
580
581LUALIB_API int luaL_len (lua_State *L, int idx) {
582  int l;
583  int isnum;
584  lua_len(L, idx);
585  l = (int)lua_tointegerx(L, -1, &isnum);
586  if (!isnum)
587    luaL_error(L, "object length is not a number");
588  lua_pop(L, 1);  /* remove object */
589  return l;
590}
591
592
593LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
594  if (!luaL_callmeta(L, idx, "__tostring")) {  /* no metafield? */
595    switch (lua_type(L, idx)) {
596      case LUA_TNUMBER:
597      case LUA_TSTRING:
598        lua_pushvalue(L, idx);
599        break;
600      case LUA_TBOOLEAN:
601        lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false"));
602        break;
603      case LUA_TNIL:
604        lua_pushliteral(L, "nil");
605        break;
606      default:
607        lua_pushfstring(L, "%s: %p", luaL_typename(L, idx),
608                                            lua_topointer(L, idx));
609        break;
610    }
611  }
612  return lua_tolstring(L, -1, len);
613}
614
615
616/*
617** {======================================================
618** Compatibility with 5.1 module functions
619** =======================================================
620*/
621#if defined(LUA_COMPAT_MODULE)
622
623static const char *luaL_findtable (lua_State *L, int idx,
624                                   const char *fname, int szhint) {
625  const char *e;
626  if (idx) lua_pushvalue(L, idx);
627  do {
628    e = strchr(fname, '.');
629    if (e == NULL) e = fname + strlen(fname);
630    lua_pushlstring(L, fname, e - fname);
631    lua_rawget(L, -2);
632    if (lua_isnil(L, -1)) {  /* no such field? */
633      lua_pop(L, 1);  /* remove this nil */
634      lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
635      lua_pushlstring(L, fname, e - fname);
636      lua_pushvalue(L, -2);
637      lua_settable(L, -4);  /* set new table into field */
638    }
639    else if (!lua_istable(L, -1)) {  /* field has a non-table value? */
640      lua_pop(L, 2);  /* remove table and value */
641      return fname;  /* return problematic part of the name */
642    }
643    lua_remove(L, -2);  /* remove previous table */
644    fname = e + 1;
645  } while (*e == '.');
646  return NULL;
647}
648
649
650/*
651** Count number of elements in a luaL_Reg list.
652*/
653static int libsize (const luaL_Reg *l) {
654  int size = 0;
655  for (; l && l->name; l++) size++;
656  return size;
657}
658
659
660/*
661** Find or create a module table with a given name. The function
662** first looks at the _LOADED table and, if that fails, try a
663** global variable with that name. In any case, leaves on the stack
664** the module table.
665*/
666LUALIB_API void luaL_pushmodule (lua_State *L, const char *modname,
667                                 int sizehint) {
668  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);  /* get _LOADED table */
669  lua_getfield(L, -1, modname);  /* get _LOADED[modname] */
670  if (!lua_istable(L, -1)) {  /* not found? */
671    lua_pop(L, 1);  /* remove previous result */
672    /* try global variable (and create one if it does not exist) */
673    lua_pushglobaltable(L);
674    if (luaL_findtable(L, 0, modname, sizehint) != NULL)
675      luaL_error(L, "name conflict for module " LUA_QS, modname);
676    lua_pushvalue(L, -1);
677    lua_setfield(L, -3, modname);  /* _LOADED[modname] = new table */
678  }
679  lua_remove(L, -2);  /* remove _LOADED table */
680}
681
682
683LUALIB_API void luaL_openlib (lua_State *L, const char *libname,
684                               const luaL_Reg *l, int nup) {
685  luaL_checkversion(L);
686  if (libname) {
687    luaL_pushmodule(L, libname, libsize(l));  /* get/create library table */
688    lua_insert(L, -(nup + 1));  /* move library table to below upvalues */
689  }
690  if (l)
691    luaL_setfuncs(L, l, nup);
692  else
693    lua_pop(L, nup);  /* remove upvalues */
694}
695
696#endif
697/* }====================================================== */
698
699/*
700** set functions from list 'l' into table at top - 'nup'; each
701** function gets the 'nup' elements at the top as upvalues.
702** Returns with only the table at the stack.
703*/
704LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
705  luaL_checkversion(L);
706  luaL_checkstack(L, nup, "too many upvalues");
707  for (; l->name != NULL; l++) {  /* fill the table with given functions */
708    int i;
709    for (i = 0; i < nup; i++)  /* copy upvalues to the top */
710      lua_pushvalue(L, -nup);
711    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
712    lua_setfield(L, -(nup + 2), l->name);
713  }
714  lua_pop(L, nup);  /* remove upvalues */
715}
716
717
718/*
719** ensure that stack[idx][fname] has a table and push that table
720** into the stack
721*/
722LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) {
723  lua_getfield(L, idx, fname);
724  if (lua_istable(L, -1)) return 1;  /* table already there */
725  else {
726    lua_pop(L, 1);  /* remove previous result */
727    idx = lua_absindex(L, idx);
728    lua_newtable(L);
729    lua_pushvalue(L, -1);  /* copy to be left at top */
730    lua_setfield(L, idx, fname);  /* assign new table to field */
731    return 0;  /* false, because did not find table there */
732  }
733}
734
735
736/*
737** stripped-down 'require'. Calls 'openf' to open a module,
738** registers the result in 'package.loaded' table and, if 'glb'
739** is true, also registers the result in the global table.
740** Leaves resulting module on the top.
741*/
742LUALIB_API void luaL_requiref (lua_State *L, const char *modname,
743                               lua_CFunction openf, int glb) {
744  lua_pushcfunction(L, openf);
745  lua_pushstring(L, modname);  /* argument to open function */
746  lua_call(L, 1, 1);  /* open module */
747  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED");
748  lua_pushvalue(L, -2);  /* make copy of module (call result) */
749  lua_setfield(L, -2, modname);  /* _LOADED[modname] = module */
750  lua_pop(L, 1);  /* remove _LOADED table */
751  if (glb) {
752    lua_pushvalue(L, -1);  /* copy of 'mod' */
753    lua_setglobal(L, modname);  /* _G[modname] = module */
754  }
755}
756
757
758LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
759                                                               const char *r) {
760  const char *wild;
761  size_t l = strlen(p);
762  luaL_Buffer b;
763  luaL_buffinit(L, &b);
764  while ((wild = strstr(s, p)) != NULL) {
765    luaL_addlstring(&b, s, wild - s);  /* push prefix */
766    luaL_addstring(&b, r);  /* push replacement in place of pattern */
767    s = wild + l;  /* continue after `p' */
768  }
769  luaL_addstring(&b, s);  /* push last suffix */
770  luaL_pushresult(&b);
771  return lua_tostring(L, -1);
772}
773
774
775LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver) {
776  const lua_Number *v = lua_version(L);
777  if (v != lua_version(NULL))
778    luaL_error(L, "multiple Lua VMs detected");
779  else if (*v != ver)
780    luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f",
781                  ver, *v);
782  /* check conversions number -> integer types */
783  lua_pushnumber(L, -(lua_Number)0x1234);
784  if (lua_tointeger(L, -1) != -0x1234 ||
785      lua_tounsigned(L, -1) != (lua_Unsigned)-0x1234)
786    luaL_error(L, "bad conversion number->int;"
787                  " must recompile Lua with proper settings");
788  lua_pop(L, 1);
789}
790
791#if defined(_KERNEL)
792
793EXPORT_SYMBOL(luaL_argerror);
794EXPORT_SYMBOL(luaL_error);
795EXPORT_SYMBOL(luaL_loadbufferx);
796EXPORT_SYMBOL(luaL_newmetatable);
797EXPORT_SYMBOL(luaL_traceback);
798
799#endif
800/* END CSTYLED */
801