1 | /* |
2 | ** $Id: lauxlib.c $ |
3 | ** Auxiliary functions for building Lua libraries |
4 | ** See Copyright Notice in lua.h |
5 | */ |
6 | |
7 | #define lauxlib_c |
8 | #define LUA_LIB |
9 | |
10 | #include "lprefix.h" |
11 | |
12 | |
13 | #include <errno.h> |
14 | #include <stdarg.h> |
15 | #include <stdio.h> |
16 | #include <stdlib.h> |
17 | #include <string.h> |
18 | |
19 | |
20 | /* |
21 | ** This file uses only the official API of Lua. |
22 | ** Any function declared here could be written as an application function. |
23 | */ |
24 | |
25 | #include "lua.h" |
26 | |
27 | #include "lauxlib.h" |
28 | |
29 | |
30 | #if !defined(MAX_SIZET) |
31 | /* maximum value for size_t */ |
32 | #define MAX_SIZET ((size_t)(~(size_t)0)) |
33 | #endif |
34 | |
35 | |
36 | /* |
37 | ** {====================================================== |
38 | ** Traceback |
39 | ** ======================================================= |
40 | */ |
41 | |
42 | |
43 | #define LEVELS1 10 /* size of the first part of the stack */ |
44 | #define LEVELS2 11 /* size of the second part of the stack */ |
45 | |
46 | |
47 | |
48 | /* |
49 | ** Search for 'objidx' in table at index -1. ('objidx' must be an |
50 | ** absolute index.) Return 1 + string at top if it found a good name. |
51 | */ |
52 | static int findfield (lua_State *L, int objidx, int level) { |
53 | if (level == 0 || !lua_istable(L, -1)) |
54 | return 0; /* not found */ |
55 | lua_pushnil(L); /* start 'next' loop */ |
56 | while (lua_next(L, -2)) { /* for each pair in table */ |
57 | if (lua_type(L, -2) == LUA_TSTRING) { /* ignore non-string keys */ |
58 | if (lua_rawequal(L, objidx, -1)) { /* found object? */ |
59 | lua_pop(L, 1); /* remove value (but keep name) */ |
60 | return 1; |
61 | } |
62 | else if (findfield(L, objidx, level - 1)) { /* try recursively */ |
63 | /* stack: lib_name, lib_table, field_name (top) */ |
64 | lua_pushliteral(L, "." ); /* place '.' between the two names */ |
65 | lua_replace(L, -3); /* (in the slot occupied by table) */ |
66 | lua_concat(L, 3); /* lib_name.field_name */ |
67 | return 1; |
68 | } |
69 | } |
70 | lua_pop(L, 1); /* remove value */ |
71 | } |
72 | return 0; /* not found */ |
73 | } |
74 | |
75 | |
76 | /* |
77 | ** Search for a name for a function in all loaded modules |
78 | */ |
79 | static int pushglobalfuncname (lua_State *L, lua_Debug *ar) { |
80 | int top = lua_gettop(L); |
81 | lua_getinfo(L, "f" , ar); /* push function */ |
82 | lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE); |
83 | if (findfield(L, top + 1, 2)) { |
84 | const char *name = lua_tostring(L, -1); |
85 | if (strncmp(name, LUA_GNAME "." , 3) == 0) { /* name start with '_G.'? */ |
86 | lua_pushstring(L, name + 3); /* push name without prefix */ |
87 | lua_remove(L, -2); /* remove original name */ |
88 | } |
89 | lua_copy(L, -1, top + 1); /* copy name to proper place */ |
90 | lua_settop(L, top + 1); /* remove table "loaded" and name copy */ |
91 | return 1; |
92 | } |
93 | else { |
94 | lua_settop(L, top); /* remove function and global table */ |
95 | return 0; |
96 | } |
97 | } |
98 | |
99 | |
100 | static void pushfuncname (lua_State *L, lua_Debug *ar) { |
101 | if (pushglobalfuncname(L, ar)) { /* try first a global name */ |
102 | lua_pushfstring(L, "function '%s'" , lua_tostring(L, -1)); |
103 | lua_remove(L, -2); /* remove name */ |
104 | } |
105 | else if (*ar->namewhat != '\0') /* is there a name from code? */ |
106 | lua_pushfstring(L, "%s '%s'" , ar->namewhat, ar->name); /* use it */ |
107 | else if (*ar->what == 'm') /* main? */ |
108 | lua_pushliteral(L, "main chunk" ); |
109 | else if (*ar->what != 'C') /* for Lua functions, use <file:line> */ |
110 | lua_pushfstring(L, "function <%s:%d>" , ar->short_src, ar->linedefined); |
111 | else /* nothing left... */ |
112 | lua_pushliteral(L, "?" ); |
113 | } |
114 | |
115 | |
116 | static int lastlevel (lua_State *L) { |
117 | lua_Debug ar; |
118 | int li = 1, le = 1; |
119 | /* find an upper bound */ |
120 | while (lua_getstack(L, le, &ar)) { li = le; le *= 2; } |
121 | /* do a binary search */ |
122 | while (li < le) { |
123 | int m = (li + le)/2; |
124 | if (lua_getstack(L, m, &ar)) li = m + 1; |
125 | else le = m; |
126 | } |
127 | return le - 1; |
128 | } |
129 | |
130 | |
131 | LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1, |
132 | const char *msg, int level) { |
133 | luaL_Buffer b; |
134 | lua_Debug ar; |
135 | int last = lastlevel(L1); |
136 | int limit2show = (last - level > LEVELS1 + LEVELS2) ? LEVELS1 : -1; |
137 | luaL_buffinit(L, &b); |
138 | if (msg) { |
139 | luaL_addstring(&b, msg); |
140 | luaL_addchar(&b, '\n'); |
141 | } |
142 | luaL_addstring(&b, "stack traceback:" ); |
143 | while (lua_getstack(L1, level++, &ar)) { |
144 | if (limit2show-- == 0) { /* too many levels? */ |
145 | int n = last - level - LEVELS2 + 1; /* number of levels to skip */ |
146 | lua_pushfstring(L, "\n\t...\t(skipping %d levels)" , n); |
147 | luaL_addvalue(&b); /* add warning about skip */ |
148 | level += n; /* and skip to last levels */ |
149 | } |
150 | else { |
151 | lua_getinfo(L1, "Slnt" , &ar); |
152 | if (ar.currentline <= 0) |
153 | lua_pushfstring(L, "\n\t%s: in " , ar.short_src); |
154 | else |
155 | lua_pushfstring(L, "\n\t%s:%d: in " , ar.short_src, ar.currentline); |
156 | luaL_addvalue(&b); |
157 | pushfuncname(L, &ar); |
158 | luaL_addvalue(&b); |
159 | if (ar.istailcall) |
160 | luaL_addstring(&b, "\n\t(...tail calls...)" ); |
161 | } |
162 | } |
163 | luaL_pushresult(&b); |
164 | } |
165 | |
166 | /* }====================================================== */ |
167 | |
168 | |
169 | /* |
170 | ** {====================================================== |
171 | ** Error-report functions |
172 | ** ======================================================= |
173 | */ |
174 | |
175 | LUALIB_API int luaL_argerror (lua_State *L, int arg, const char *) { |
176 | lua_Debug ar; |
177 | if (!lua_getstack(L, 0, &ar)) /* no stack frame? */ |
178 | return luaL_error(L, "bad argument #%d (%s)" , arg, extramsg); |
179 | lua_getinfo(L, "n" , &ar); |
180 | if (strcmp(ar.namewhat, "method" ) == 0) { |
181 | arg--; /* do not count 'self' */ |
182 | if (arg == 0) /* error is in the self argument itself? */ |
183 | return luaL_error(L, "calling '%s' on bad self (%s)" , |
184 | ar.name, extramsg); |
185 | } |
186 | if (ar.name == NULL) |
187 | ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?" ; |
188 | return luaL_error(L, "bad argument #%d to '%s' (%s)" , |
189 | arg, ar.name, extramsg); |
190 | } |
191 | |
192 | |
193 | int luaL_typeerror (lua_State *L, int arg, const char *tname) { |
194 | const char *msg; |
195 | const char *typearg; /* name for the type of the actual argument */ |
196 | if (luaL_getmetafield(L, arg, "__name" ) == LUA_TSTRING) |
197 | typearg = lua_tostring(L, -1); /* use the given type name */ |
198 | else if (lua_type(L, arg) == LUA_TLIGHTUSERDATA) |
199 | typearg = "light userdata" ; /* special name for messages */ |
200 | else |
201 | typearg = luaL_typename(L, arg); /* standard name */ |
202 | msg = lua_pushfstring(L, "%s expected, got %s" , tname, typearg); |
203 | return luaL_argerror(L, arg, msg); |
204 | } |
205 | |
206 | |
207 | static void tag_error (lua_State *L, int arg, int tag) { |
208 | luaL_typeerror(L, arg, lua_typename(L, tag)); |
209 | } |
210 | |
211 | |
212 | /* |
213 | ** The use of 'lua_pushfstring' ensures this function does not |
214 | ** need reserved stack space when called. |
215 | */ |
216 | LUALIB_API void luaL_where (lua_State *L, int level) { |
217 | lua_Debug ar; |
218 | if (lua_getstack(L, level, &ar)) { /* check function at level */ |
219 | lua_getinfo(L, "Sl" , &ar); /* get info about it */ |
220 | if (ar.currentline > 0) { /* is there info? */ |
221 | lua_pushfstring(L, "%s:%d: " , ar.short_src, ar.currentline); |
222 | return; |
223 | } |
224 | } |
225 | lua_pushfstring(L, "" ); /* else, no information available... */ |
226 | } |
227 | |
228 | |
229 | /* |
230 | ** Again, the use of 'lua_pushvfstring' ensures this function does |
231 | ** not need reserved stack space when called. (At worst, it generates |
232 | ** an error with "stack overflow" instead of the given message.) |
233 | */ |
234 | LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) { |
235 | va_list argp; |
236 | va_start(argp, fmt); |
237 | luaL_where(L, 1); |
238 | lua_pushvfstring(L, fmt, argp); |
239 | va_end(argp); |
240 | lua_concat(L, 2); |
241 | return lua_error(L); |
242 | } |
243 | |
244 | |
245 | LUALIB_API int luaL_fileresult (lua_State *L, int stat, const char *fname) { |
246 | int en = errno; /* calls to Lua API may change this value */ |
247 | if (stat) { |
248 | lua_pushboolean(L, 1); |
249 | return 1; |
250 | } |
251 | else { |
252 | luaL_pushfail(L); |
253 | if (fname) |
254 | lua_pushfstring(L, "%s: %s" , fname, strerror(en)); |
255 | else |
256 | lua_pushstring(L, strerror(en)); |
257 | lua_pushinteger(L, en); |
258 | return 3; |
259 | } |
260 | } |
261 | |
262 | |
263 | #if !defined(l_inspectstat) /* { */ |
264 | |
265 | #if defined(LUA_USE_POSIX) |
266 | |
267 | #include <sys/wait.h> |
268 | |
269 | /* |
270 | ** use appropriate macros to interpret 'pclose' return status |
271 | */ |
272 | #define l_inspectstat(stat,what) \ |
273 | if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \ |
274 | else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; } |
275 | |
276 | #else |
277 | |
278 | #define l_inspectstat(stat,what) /* no op */ |
279 | |
280 | #endif |
281 | |
282 | #endif /* } */ |
283 | |
284 | |
285 | LUALIB_API int luaL_execresult (lua_State *L, int stat) { |
286 | const char *what = "exit" ; /* type of termination */ |
287 | if (stat != 0 && errno != 0) /* error with an 'errno'? */ |
288 | return luaL_fileresult(L, 0, NULL); |
289 | else { |
290 | l_inspectstat(stat, what); /* interpret result */ |
291 | if (*what == 'e' && stat == 0) /* successful termination? */ |
292 | lua_pushboolean(L, 1); |
293 | else |
294 | luaL_pushfail(L); |
295 | lua_pushstring(L, what); |
296 | lua_pushinteger(L, stat); |
297 | return 3; /* return true/fail,what,code */ |
298 | } |
299 | } |
300 | |
301 | /* }====================================================== */ |
302 | |
303 | |
304 | |
305 | /* |
306 | ** {====================================================== |
307 | ** Userdata's metatable manipulation |
308 | ** ======================================================= |
309 | */ |
310 | |
311 | LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) { |
312 | if (luaL_getmetatable(L, tname) != LUA_TNIL) /* name already in use? */ |
313 | return 0; /* leave previous value on top, but return 0 */ |
314 | lua_pop(L, 1); |
315 | lua_createtable(L, 0, 2); /* create metatable */ |
316 | lua_pushstring(L, tname); |
317 | lua_setfield(L, -2, "__name" ); /* metatable.__name = tname */ |
318 | lua_pushvalue(L, -1); |
319 | lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */ |
320 | return 1; |
321 | } |
322 | |
323 | |
324 | LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) { |
325 | luaL_getmetatable(L, tname); |
326 | lua_setmetatable(L, -2); |
327 | } |
328 | |
329 | |
330 | LUALIB_API void *luaL_testudata (lua_State *L, int ud, const char *tname) { |
331 | void *p = lua_touserdata(L, ud); |
332 | if (p != NULL) { /* value is a userdata? */ |
333 | if (lua_getmetatable(L, ud)) { /* does it have a metatable? */ |
334 | luaL_getmetatable(L, tname); /* get correct metatable */ |
335 | if (!lua_rawequal(L, -1, -2)) /* not the same? */ |
336 | p = NULL; /* value is a userdata with wrong metatable */ |
337 | lua_pop(L, 2); /* remove both metatables */ |
338 | return p; |
339 | } |
340 | } |
341 | return NULL; /* value is not a userdata with a metatable */ |
342 | } |
343 | |
344 | |
345 | LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) { |
346 | void *p = luaL_testudata(L, ud, tname); |
347 | luaL_argexpected(L, p != NULL, ud, tname); |
348 | return p; |
349 | } |
350 | |
351 | /* }====================================================== */ |
352 | |
353 | |
354 | /* |
355 | ** {====================================================== |
356 | ** Argument check functions |
357 | ** ======================================================= |
358 | */ |
359 | |
360 | LUALIB_API int luaL_checkoption (lua_State *L, int arg, const char *def, |
361 | const char *const lst[]) { |
362 | const char *name = (def) ? luaL_optstring(L, arg, def) : |
363 | luaL_checkstring(L, arg); |
364 | int i; |
365 | for (i=0; lst[i]; i++) |
366 | if (strcmp(lst[i], name) == 0) |
367 | return i; |
368 | return luaL_argerror(L, arg, |
369 | lua_pushfstring(L, "invalid option '%s'" , name)); |
370 | } |
371 | |
372 | |
373 | /* |
374 | ** Ensures the stack has at least 'space' extra slots, raising an error |
375 | ** if it cannot fulfill the request. (The error handling needs a few |
376 | ** extra slots to format the error message. In case of an error without |
377 | ** this extra space, Lua will generate the same 'stack overflow' error, |
378 | ** but without 'msg'.) |
379 | */ |
380 | LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) { |
381 | if (!lua_checkstack(L, space)) { |
382 | if (msg) |
383 | luaL_error(L, "stack overflow (%s)" , msg); |
384 | else |
385 | luaL_error(L, "stack overflow" ); |
386 | } |
387 | } |
388 | |
389 | |
390 | LUALIB_API void luaL_checktype (lua_State *L, int arg, int t) { |
391 | if (lua_type(L, arg) != t) |
392 | tag_error(L, arg, t); |
393 | } |
394 | |
395 | |
396 | LUALIB_API void luaL_checkany (lua_State *L, int arg) { |
397 | if (lua_type(L, arg) == LUA_TNONE) |
398 | luaL_argerror(L, arg, "value expected" ); |
399 | } |
400 | |
401 | |
402 | LUALIB_API const char *luaL_checklstring (lua_State *L, int arg, size_t *len) { |
403 | const char *s = lua_tolstring(L, arg, len); |
404 | if (!s) tag_error(L, arg, LUA_TSTRING); |
405 | return s; |
406 | } |
407 | |
408 | |
409 | LUALIB_API const char *luaL_optlstring (lua_State *L, int arg, |
410 | const char *def, size_t *len) { |
411 | if (lua_isnoneornil(L, arg)) { |
412 | if (len) |
413 | *len = (def ? strlen(def) : 0); |
414 | return def; |
415 | } |
416 | else return luaL_checklstring(L, arg, len); |
417 | } |
418 | |
419 | |
420 | LUALIB_API lua_Number luaL_checknumber (lua_State *L, int arg) { |
421 | int isnum; |
422 | lua_Number d = lua_tonumberx(L, arg, &isnum); |
423 | if (!isnum) |
424 | tag_error(L, arg, LUA_TNUMBER); |
425 | return d; |
426 | } |
427 | |
428 | |
429 | LUALIB_API lua_Number luaL_optnumber (lua_State *L, int arg, lua_Number def) { |
430 | return luaL_opt(L, luaL_checknumber, arg, def); |
431 | } |
432 | |
433 | |
434 | static void interror (lua_State *L, int arg) { |
435 | if (lua_isnumber(L, arg)) |
436 | luaL_argerror(L, arg, "number has no integer representation" ); |
437 | else |
438 | tag_error(L, arg, LUA_TNUMBER); |
439 | } |
440 | |
441 | |
442 | LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int arg) { |
443 | int isnum; |
444 | lua_Integer d = lua_tointegerx(L, arg, &isnum); |
445 | if (!isnum) { |
446 | interror(L, arg); |
447 | } |
448 | return d; |
449 | } |
450 | |
451 | |
452 | LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int arg, |
453 | lua_Integer def) { |
454 | return luaL_opt(L, luaL_checkinteger, arg, def); |
455 | } |
456 | |
457 | /* }====================================================== */ |
458 | |
459 | |
460 | /* |
461 | ** {====================================================== |
462 | ** Generic Buffer manipulation |
463 | ** ======================================================= |
464 | */ |
465 | |
466 | /* userdata to box arbitrary data */ |
467 | typedef struct UBox { |
468 | void *box; |
469 | size_t bsize; |
470 | } UBox; |
471 | |
472 | |
473 | static void *resizebox (lua_State *L, int idx, size_t newsize) { |
474 | void *ud; |
475 | lua_Alloc allocf = lua_getallocf(L, &ud); |
476 | UBox *box = (UBox *)lua_touserdata(L, idx); |
477 | void *temp = allocf(ud, box->box, box->bsize, newsize); |
478 | if (temp == NULL && newsize > 0) { /* allocation error? */ |
479 | lua_pushliteral(L, "not enough memory" ); |
480 | lua_error(L); /* raise a memory error */ |
481 | } |
482 | box->box = temp; |
483 | box->bsize = newsize; |
484 | return temp; |
485 | } |
486 | |
487 | |
488 | static int boxgc (lua_State *L) { |
489 | resizebox(L, 1, 0); |
490 | return 0; |
491 | } |
492 | |
493 | |
494 | static const luaL_Reg boxmt[] = { /* box metamethods */ |
495 | {"__gc" , boxgc}, |
496 | {"__close" , boxgc}, |
497 | {NULL, NULL} |
498 | }; |
499 | |
500 | |
501 | static void newbox (lua_State *L) { |
502 | UBox *box = (UBox *)lua_newuserdatauv(L, sizeof(UBox), 0); |
503 | box->box = NULL; |
504 | box->bsize = 0; |
505 | if (luaL_newmetatable(L, "_UBOX*" )) /* creating metatable? */ |
506 | luaL_setfuncs(L, boxmt, 0); /* set its metamethods */ |
507 | lua_setmetatable(L, -2); |
508 | } |
509 | |
510 | |
511 | /* |
512 | ** check whether buffer is using a userdata on the stack as a temporary |
513 | ** buffer |
514 | */ |
515 | #define buffonstack(B) ((B)->b != (B)->init.b) |
516 | |
517 | |
518 | /* |
519 | ** Compute new size for buffer 'B', enough to accommodate extra 'sz' |
520 | ** bytes. |
521 | */ |
522 | static size_t newbuffsize (luaL_Buffer *B, size_t sz) { |
523 | size_t newsize = B->size * 2; /* double buffer size */ |
524 | if (MAX_SIZET - sz < B->n) /* overflow in (B->n + sz)? */ |
525 | return luaL_error(B->L, "buffer too large" ); |
526 | if (newsize < B->n + sz) /* double is not big enough? */ |
527 | newsize = B->n + sz; |
528 | return newsize; |
529 | } |
530 | |
531 | |
532 | /* |
533 | ** Returns a pointer to a free area with at least 'sz' bytes in buffer |
534 | ** 'B'. 'boxidx' is the relative position in the stack where the |
535 | ** buffer's box is or should be. |
536 | */ |
537 | static char *prepbuffsize (luaL_Buffer *B, size_t sz, int boxidx) { |
538 | if (B->size - B->n >= sz) /* enough space? */ |
539 | return B->b + B->n; |
540 | else { |
541 | lua_State *L = B->L; |
542 | char *newbuff; |
543 | size_t newsize = newbuffsize(B, sz); |
544 | /* create larger buffer */ |
545 | if (buffonstack(B)) /* buffer already has a box? */ |
546 | newbuff = (char *)resizebox(L, boxidx, newsize); /* resize it */ |
547 | else { /* no box yet */ |
548 | lua_pushnil(L); /* reserve slot for final result */ |
549 | newbox(L); /* create a new box */ |
550 | /* move box (and slot) to its intended position */ |
551 | lua_rotate(L, boxidx - 1, 2); |
552 | lua_toclose(L, boxidx); |
553 | newbuff = (char *)resizebox(L, boxidx, newsize); |
554 | memcpy(newbuff, B->b, B->n * sizeof(char)); /* copy original content */ |
555 | } |
556 | B->b = newbuff; |
557 | B->size = newsize; |
558 | return newbuff + B->n; |
559 | } |
560 | } |
561 | |
562 | /* |
563 | ** returns a pointer to a free area with at least 'sz' bytes |
564 | */ |
565 | LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) { |
566 | return prepbuffsize(B, sz, -1); |
567 | } |
568 | |
569 | |
570 | LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) { |
571 | if (l > 0) { /* avoid 'memcpy' when 's' can be NULL */ |
572 | char *b = prepbuffsize(B, l, -1); |
573 | memcpy(b, s, l * sizeof(char)); |
574 | luaL_addsize(B, l); |
575 | } |
576 | } |
577 | |
578 | |
579 | LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) { |
580 | luaL_addlstring(B, s, strlen(s)); |
581 | } |
582 | |
583 | |
584 | LUALIB_API void luaL_pushresult (luaL_Buffer *B) { |
585 | lua_State *L = B->L; |
586 | lua_pushlstring(L, B->b, B->n); |
587 | if (buffonstack(B)) { |
588 | lua_copy(L, -1, -3); /* move string to reserved slot */ |
589 | lua_pop(L, 2); /* pop string and box (closing the box) */ |
590 | } |
591 | } |
592 | |
593 | |
594 | LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) { |
595 | luaL_addsize(B, sz); |
596 | luaL_pushresult(B); |
597 | } |
598 | |
599 | |
600 | /* |
601 | ** 'luaL_addvalue' is the only function in the Buffer system where the |
602 | ** box (if existent) is not on the top of the stack. So, instead of |
603 | ** calling 'luaL_addlstring', it replicates the code using -2 as the |
604 | ** last argument to 'prepbuffsize', signaling that the box is (or will |
605 | ** be) bellow the string being added to the buffer. (Box creation can |
606 | ** trigger an emergency GC, so we should not remove the string from the |
607 | ** stack before we have the space guaranteed.) |
608 | */ |
609 | LUALIB_API void luaL_addvalue (luaL_Buffer *B) { |
610 | lua_State *L = B->L; |
611 | size_t len; |
612 | const char *s = lua_tolstring(L, -1, &len); |
613 | char *b = prepbuffsize(B, len, -2); |
614 | memcpy(b, s, len * sizeof(char)); |
615 | luaL_addsize(B, len); |
616 | lua_pop(L, 1); /* pop string */ |
617 | } |
618 | |
619 | |
620 | LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { |
621 | B->L = L; |
622 | B->b = B->init.b; |
623 | B->n = 0; |
624 | B->size = LUAL_BUFFERSIZE; |
625 | } |
626 | |
627 | |
628 | LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) { |
629 | luaL_buffinit(L, B); |
630 | return prepbuffsize(B, sz, -1); |
631 | } |
632 | |
633 | /* }====================================================== */ |
634 | |
635 | |
636 | /* |
637 | ** {====================================================== |
638 | ** Reference system |
639 | ** ======================================================= |
640 | */ |
641 | |
642 | /* index of free-list header */ |
643 | #define freelist 0 |
644 | |
645 | |
646 | LUALIB_API int luaL_ref (lua_State *L, int t) { |
647 | int ref; |
648 | if (lua_isnil(L, -1)) { |
649 | lua_pop(L, 1); /* remove from stack */ |
650 | return LUA_REFNIL; /* 'nil' has a unique fixed reference */ |
651 | } |
652 | t = lua_absindex(L, t); |
653 | lua_rawgeti(L, t, freelist); /* get first free element */ |
654 | ref = (int)lua_tointeger(L, -1); /* ref = t[freelist] */ |
655 | lua_pop(L, 1); /* remove it from stack */ |
656 | if (ref != 0) { /* any free element? */ |
657 | lua_rawgeti(L, t, ref); /* remove it from list */ |
658 | lua_rawseti(L, t, freelist); /* (t[freelist] = t[ref]) */ |
659 | } |
660 | else /* no free elements */ |
661 | ref = (int)lua_rawlen(L, t) + 1; /* get a new reference */ |
662 | lua_rawseti(L, t, ref); |
663 | return ref; |
664 | } |
665 | |
666 | |
667 | LUALIB_API void luaL_unref (lua_State *L, int t, int ref) { |
668 | if (ref >= 0) { |
669 | t = lua_absindex(L, t); |
670 | lua_rawgeti(L, t, freelist); |
671 | lua_rawseti(L, t, ref); /* t[ref] = t[freelist] */ |
672 | lua_pushinteger(L, ref); |
673 | lua_rawseti(L, t, freelist); /* t[freelist] = ref */ |
674 | } |
675 | } |
676 | |
677 | /* }====================================================== */ |
678 | |
679 | |
680 | /* |
681 | ** {====================================================== |
682 | ** Load functions |
683 | ** ======================================================= |
684 | */ |
685 | |
686 | typedef struct LoadF { |
687 | int n; /* number of pre-read characters */ |
688 | FILE *f; /* file being read */ |
689 | char buff[BUFSIZ]; /* area for reading file */ |
690 | } LoadF; |
691 | |
692 | |
693 | static const char *getF (lua_State *L, void *ud, size_t *size) { |
694 | LoadF *lf = (LoadF *)ud; |
695 | (void)L; /* not used */ |
696 | if (lf->n > 0) { /* are there pre-read characters to be read? */ |
697 | *size = lf->n; /* return them (chars already in buffer) */ |
698 | lf->n = 0; /* no more pre-read characters */ |
699 | } |
700 | else { /* read a block from file */ |
701 | /* 'fread' can return > 0 *and* set the EOF flag. If next call to |
702 | 'getF' called 'fread', it might still wait for user input. |
703 | The next check avoids this problem. */ |
704 | if (feof(lf->f)) return NULL; |
705 | *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f); /* read block */ |
706 | } |
707 | return lf->buff; |
708 | } |
709 | |
710 | |
711 | static int errfile (lua_State *L, const char *what, int fnameindex) { |
712 | const char *serr = strerror(errno); |
713 | const char *filename = lua_tostring(L, fnameindex) + 1; |
714 | lua_pushfstring(L, "cannot %s %s: %s" , what, filename, serr); |
715 | lua_remove(L, fnameindex); |
716 | return LUA_ERRFILE; |
717 | } |
718 | |
719 | |
720 | static int skipBOM (LoadF *lf) { |
721 | const char *p = "\xEF\xBB\xBF" ; /* UTF-8 BOM mark */ |
722 | int c; |
723 | lf->n = 0; |
724 | do { |
725 | c = getc(lf->f); |
726 | if (c == EOF || c != *(const unsigned char *)p++) return c; |
727 | lf->buff[lf->n++] = c; /* to be read by the parser */ |
728 | } while (*p != '\0'); |
729 | lf->n = 0; /* prefix matched; discard it */ |
730 | return getc(lf->f); /* return next character */ |
731 | } |
732 | |
733 | |
734 | /* |
735 | ** reads the first character of file 'f' and skips an optional BOM mark |
736 | ** in its beginning plus its first line if it starts with '#'. Returns |
737 | ** true if it skipped the first line. In any case, '*cp' has the |
738 | ** first "valid" character of the file (after the optional BOM and |
739 | ** a first-line comment). |
740 | */ |
741 | static int (LoadF *lf, int *cp) { |
742 | int c = *cp = skipBOM(lf); |
743 | if (c == '#') { /* first line is a comment (Unix exec. file)? */ |
744 | do { /* skip first line */ |
745 | c = getc(lf->f); |
746 | } while (c != EOF && c != '\n'); |
747 | *cp = getc(lf->f); /* skip end-of-line, if present */ |
748 | return 1; /* there was a comment */ |
749 | } |
750 | else return 0; /* no comment */ |
751 | } |
752 | |
753 | |
754 | LUALIB_API int luaL_loadfilex (lua_State *L, const char *filename, |
755 | const char *mode) { |
756 | LoadF lf; |
757 | int status, readstatus; |
758 | int c; |
759 | int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */ |
760 | if (filename == NULL) { |
761 | lua_pushliteral(L, "=stdin" ); |
762 | lf.f = stdin; |
763 | } |
764 | else { |
765 | lua_pushfstring(L, "@%s" , filename); |
766 | lf.f = fopen(filename, "r" ); |
767 | if (lf.f == NULL) return errfile(L, "open" , fnameindex); |
768 | } |
769 | if (skipcomment(&lf, &c)) /* read initial portion */ |
770 | lf.buff[lf.n++] = '\n'; /* add line to correct line numbers */ |
771 | if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */ |
772 | lf.f = freopen(filename, "rb" , lf.f); /* reopen in binary mode */ |
773 | if (lf.f == NULL) return errfile(L, "reopen" , fnameindex); |
774 | skipcomment(&lf, &c); /* re-read initial portion */ |
775 | } |
776 | if (c != EOF) |
777 | lf.buff[lf.n++] = c; /* 'c' is the first character of the stream */ |
778 | status = lua_load(L, getF, &lf, lua_tostring(L, -1), mode); |
779 | readstatus = ferror(lf.f); |
780 | if (filename) fclose(lf.f); /* close file (even in case of errors) */ |
781 | if (readstatus) { |
782 | lua_settop(L, fnameindex); /* ignore results from 'lua_load' */ |
783 | return errfile(L, "read" , fnameindex); |
784 | } |
785 | lua_remove(L, fnameindex); |
786 | return status; |
787 | } |
788 | |
789 | |
790 | typedef struct LoadS { |
791 | const char *s; |
792 | size_t size; |
793 | } LoadS; |
794 | |
795 | |
796 | static const char *getS (lua_State *L, void *ud, size_t *size) { |
797 | LoadS *ls = (LoadS *)ud; |
798 | (void)L; /* not used */ |
799 | if (ls->size == 0) return NULL; |
800 | *size = ls->size; |
801 | ls->size = 0; |
802 | return ls->s; |
803 | } |
804 | |
805 | |
806 | LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size, |
807 | const char *name, const char *mode) { |
808 | LoadS ls; |
809 | ls.s = buff; |
810 | ls.size = size; |
811 | return lua_load(L, getS, &ls, name, mode); |
812 | } |
813 | |
814 | |
815 | LUALIB_API int luaL_loadstring (lua_State *L, const char *s) { |
816 | return luaL_loadbuffer(L, s, strlen(s), s); |
817 | } |
818 | |
819 | /* }====================================================== */ |
820 | |
821 | |
822 | |
823 | LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) { |
824 | if (!lua_getmetatable(L, obj)) /* no metatable? */ |
825 | return LUA_TNIL; |
826 | else { |
827 | int tt; |
828 | lua_pushstring(L, event); |
829 | tt = lua_rawget(L, -2); |
830 | if (tt == LUA_TNIL) /* is metafield nil? */ |
831 | lua_pop(L, 2); /* remove metatable and metafield */ |
832 | else |
833 | lua_remove(L, -2); /* remove only metatable */ |
834 | return tt; /* return metafield type */ |
835 | } |
836 | } |
837 | |
838 | |
839 | LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) { |
840 | obj = lua_absindex(L, obj); |
841 | if (luaL_getmetafield(L, obj, event) == LUA_TNIL) /* no metafield? */ |
842 | return 0; |
843 | lua_pushvalue(L, obj); |
844 | lua_call(L, 1, 1); |
845 | return 1; |
846 | } |
847 | |
848 | |
849 | LUALIB_API lua_Integer luaL_len (lua_State *L, int idx) { |
850 | lua_Integer l; |
851 | int isnum; |
852 | lua_len(L, idx); |
853 | l = lua_tointegerx(L, -1, &isnum); |
854 | if (!isnum) |
855 | luaL_error(L, "object length is not an integer" ); |
856 | lua_pop(L, 1); /* remove object */ |
857 | return l; |
858 | } |
859 | |
860 | |
861 | LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) { |
862 | if (luaL_callmeta(L, idx, "__tostring" )) { /* metafield? */ |
863 | if (!lua_isstring(L, -1)) |
864 | luaL_error(L, "'__tostring' must return a string" ); |
865 | } |
866 | else { |
867 | switch (lua_type(L, idx)) { |
868 | case LUA_TNUMBER: { |
869 | if (lua_isinteger(L, idx)) |
870 | lua_pushfstring(L, "%I" , (LUAI_UACINT)lua_tointeger(L, idx)); |
871 | else |
872 | lua_pushfstring(L, "%f" , (LUAI_UACNUMBER)lua_tonumber(L, idx)); |
873 | break; |
874 | } |
875 | case LUA_TSTRING: |
876 | lua_pushvalue(L, idx); |
877 | break; |
878 | case LUA_TBOOLEAN: |
879 | lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false" )); |
880 | break; |
881 | case LUA_TNIL: |
882 | lua_pushliteral(L, "nil" ); |
883 | break; |
884 | default: { |
885 | int tt = luaL_getmetafield(L, idx, "__name" ); /* try name */ |
886 | const char *kind = (tt == LUA_TSTRING) ? lua_tostring(L, -1) : |
887 | luaL_typename(L, idx); |
888 | lua_pushfstring(L, "%s: %p" , kind, lua_topointer(L, idx)); |
889 | if (tt != LUA_TNIL) |
890 | lua_remove(L, -2); /* remove '__name' */ |
891 | break; |
892 | } |
893 | } |
894 | } |
895 | return lua_tolstring(L, -1, len); |
896 | } |
897 | |
898 | |
899 | /* |
900 | ** set functions from list 'l' into table at top - 'nup'; each |
901 | ** function gets the 'nup' elements at the top as upvalues. |
902 | ** Returns with only the table at the stack. |
903 | */ |
904 | LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) { |
905 | luaL_checkstack(L, nup, "too many upvalues" ); |
906 | for (; l->name != NULL; l++) { /* fill the table with given functions */ |
907 | if (l->func == NULL) /* place holder? */ |
908 | lua_pushboolean(L, 0); |
909 | else { |
910 | int i; |
911 | for (i = 0; i < nup; i++) /* copy upvalues to the top */ |
912 | lua_pushvalue(L, -nup); |
913 | lua_pushcclosure(L, l->func, nup); /* closure with those upvalues */ |
914 | } |
915 | lua_setfield(L, -(nup + 2), l->name); |
916 | } |
917 | lua_pop(L, nup); /* remove upvalues */ |
918 | } |
919 | |
920 | |
921 | /* |
922 | ** ensure that stack[idx][fname] has a table and push that table |
923 | ** into the stack |
924 | */ |
925 | LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) { |
926 | if (lua_getfield(L, idx, fname) == LUA_TTABLE) |
927 | return 1; /* table already there */ |
928 | else { |
929 | lua_pop(L, 1); /* remove previous result */ |
930 | idx = lua_absindex(L, idx); |
931 | lua_newtable(L); |
932 | lua_pushvalue(L, -1); /* copy to be left at top */ |
933 | lua_setfield(L, idx, fname); /* assign new table to field */ |
934 | return 0; /* false, because did not find table there */ |
935 | } |
936 | } |
937 | |
938 | |
939 | /* |
940 | ** Stripped-down 'require': After checking "loaded" table, calls 'openf' |
941 | ** to open a module, registers the result in 'package.loaded' table and, |
942 | ** if 'glb' is true, also registers the result in the global table. |
943 | ** Leaves resulting module on the top. |
944 | */ |
945 | LUALIB_API void luaL_requiref (lua_State *L, const char *modname, |
946 | lua_CFunction openf, int glb) { |
947 | luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE); |
948 | lua_getfield(L, -1, modname); /* LOADED[modname] */ |
949 | if (!lua_toboolean(L, -1)) { /* package not already loaded? */ |
950 | lua_pop(L, 1); /* remove field */ |
951 | lua_pushcfunction(L, openf); |
952 | lua_pushstring(L, modname); /* argument to open function */ |
953 | lua_call(L, 1, 1); /* call 'openf' to open module */ |
954 | lua_pushvalue(L, -1); /* make copy of module (call result) */ |
955 | lua_setfield(L, -3, modname); /* LOADED[modname] = module */ |
956 | } |
957 | lua_remove(L, -2); /* remove LOADED table */ |
958 | if (glb) { |
959 | lua_pushvalue(L, -1); /* copy of module */ |
960 | lua_setglobal(L, modname); /* _G[modname] = module */ |
961 | } |
962 | } |
963 | |
964 | |
965 | LUALIB_API void luaL_addgsub (luaL_Buffer *b, const char *s, |
966 | const char *p, const char *r) { |
967 | const char *wild; |
968 | size_t l = strlen(p); |
969 | while ((wild = strstr(s, p)) != NULL) { |
970 | luaL_addlstring(b, s, wild - s); /* push prefix */ |
971 | luaL_addstring(b, r); /* push replacement in place of pattern */ |
972 | s = wild + l; /* continue after 'p' */ |
973 | } |
974 | luaL_addstring(b, s); /* push last suffix */ |
975 | } |
976 | |
977 | |
978 | LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, |
979 | const char *p, const char *r) { |
980 | luaL_Buffer b; |
981 | luaL_buffinit(L, &b); |
982 | luaL_addgsub(&b, s, p, r); |
983 | luaL_pushresult(&b); |
984 | return lua_tostring(L, -1); |
985 | } |
986 | |
987 | |
988 | static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { |
989 | (void)ud; (void)osize; /* not used */ |
990 | if (nsize == 0) { |
991 | free(ptr); |
992 | return NULL; |
993 | } |
994 | else |
995 | return realloc(ptr, nsize); |
996 | } |
997 | |
998 | |
999 | static int panic (lua_State *L) { |
1000 | const char *msg = lua_tostring(L, -1); |
1001 | if (msg == NULL) msg = "error object is not a string" ; |
1002 | lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n" , |
1003 | msg); |
1004 | return 0; /* return to Lua to abort */ |
1005 | } |
1006 | |
1007 | |
1008 | /* |
1009 | ** Emit a warning. '*warnstate' means: |
1010 | ** 0 - warning system is off; |
1011 | ** 1 - ready to start a new message; |
1012 | ** 2 - previous message is to be continued. |
1013 | */ |
1014 | static void warnf (void *ud, const char *message, int tocont) { |
1015 | int *warnstate = (int *)ud; |
1016 | if (*warnstate != 2 && !tocont && *message == '@') { /* control message? */ |
1017 | if (strcmp(message, "@off" ) == 0) |
1018 | *warnstate = 0; |
1019 | else if (strcmp(message, "@on" ) == 0) |
1020 | *warnstate = 1; |
1021 | return; |
1022 | } |
1023 | else if (*warnstate == 0) /* warnings off? */ |
1024 | return; |
1025 | if (*warnstate == 1) /* previous message was the last? */ |
1026 | lua_writestringerror("%s" , "Lua warning: " ); /* start a new warning */ |
1027 | lua_writestringerror("%s" , message); /* write message */ |
1028 | if (tocont) /* not the last part? */ |
1029 | *warnstate = 2; /* to be continued */ |
1030 | else { /* last part */ |
1031 | lua_writestringerror("%s" , "\n" ); /* finish message with end-of-line */ |
1032 | *warnstate = 1; /* ready to start a new message */ |
1033 | } |
1034 | } |
1035 | |
1036 | |
1037 | LUALIB_API lua_State *luaL_newstate (void) { |
1038 | lua_State *L = lua_newstate(l_alloc, NULL); |
1039 | if (L) { |
1040 | int *warnstate; /* space for warning state */ |
1041 | lua_atpanic(L, &panic); |
1042 | warnstate = (int *)lua_newuserdatauv(L, sizeof(int), 0); |
1043 | luaL_ref(L, LUA_REGISTRYINDEX); /* make sure it won't be collected */ |
1044 | *warnstate = 0; /* default is warnings off */ |
1045 | lua_setwarnf(L, warnf, warnstate); |
1046 | } |
1047 | return L; |
1048 | } |
1049 | |
1050 | |
1051 | LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver, size_t sz) { |
1052 | lua_Number v = lua_version(L); |
1053 | if (sz != LUAL_NUMSIZES) /* check numeric types */ |
1054 | luaL_error(L, "core and library have incompatible numeric types" ); |
1055 | else if (v != ver) |
1056 | luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f" , |
1057 | (LUAI_UACNUMBER)ver, (LUAI_UACNUMBER)v); |
1058 | } |
1059 | |
1060 | |