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| 1 /* |
| 2 ** $Id: lauxlib.c,v 1.248 2013/03/21 13:54:57 roberto Exp $ |
| 3 ** Auxiliary functions for building Lua libraries |
| 4 ** See Copyright Notice in lua.h |
| 5 */ |
| 6 |
| 7 |
| 8 #include <errno.h> |
| 9 #include <stdarg.h> |
| 10 #include <stdio.h> |
| 11 #include <stdlib.h> |
| 12 #include <string.h> |
| 13 |
| 14 |
| 15 /* This file uses only the official API of Lua. |
| 16 ** Any function declared here could be written as an application function. |
| 17 */ |
| 18 |
| 19 #define lauxlib_c |
| 20 #define LUA_LIB |
| 21 |
| 22 #include "lua.h" |
| 23 |
| 24 #include "lauxlib.h" |
| 25 |
| 26 |
| 27 /* |
| 28 ** {====================================================== |
| 29 ** Traceback |
| 30 ** ======================================================= |
| 31 */ |
| 32 |
| 33 |
| 34 #define LEVELS1 12 /* size of the first part of the stack */ |
| 35 #define LEVELS2 10 /* size of the second part of the stack */ |
| 36 |
| 37 |
| 38 |
| 39 /* |
| 40 ** search for 'objidx' in table at index -1. |
| 41 ** return 1 + string at top if find a good name. |
| 42 */ |
| 43 static int findfield (lua_State *L, int objidx, int level) { |
| 44 if (level == 0 || !lua_istable(L, -1)) |
| 45 return 0; /* not found */ |
| 46 lua_pushnil(L); /* start 'next' loop */ |
| 47 while (lua_next(L, -2)) { /* for each pair in table */ |
| 48 if (lua_type(L, -2) == LUA_TSTRING) { /* ignore non-string keys */ |
| 49 if (lua_rawequal(L, objidx, -1)) { /* found object? */ |
| 50 lua_pop(L, 1); /* remove value (but keep name) */ |
| 51 return 1; |
| 52 } |
| 53 else if (findfield(L, objidx, level - 1)) { /* try recursively */ |
| 54 lua_remove(L, -2); /* remove table (but keep name) */ |
| 55 lua_pushliteral(L, "."); |
| 56 lua_insert(L, -2); /* place '.' between the two names */ |
| 57 lua_concat(L, 3); |
| 58 return 1; |
| 59 } |
| 60 } |
| 61 lua_pop(L, 1); /* remove value */ |
| 62 } |
| 63 return 0; /* not found */ |
| 64 } |
| 65 |
| 66 |
| 67 static int pushglobalfuncname (lua_State *L, lua_Debug *ar) { |
| 68 int top = lua_gettop(L); |
| 69 lua_getinfo(L, "f", ar); /* push function */ |
| 70 lua_pushglobaltable(L); |
| 71 if (findfield(L, top + 1, 2)) { |
| 72 lua_copy(L, -1, top + 1); /* move name to proper place */ |
| 73 lua_pop(L, 2); /* remove pushed values */ |
| 74 return 1; |
| 75 } |
| 76 else { |
| 77 lua_settop(L, top); /* remove function and global table */ |
| 78 return 0; |
| 79 } |
| 80 } |
| 81 |
| 82 |
| 83 static void pushfuncname (lua_State *L, lua_Debug *ar) { |
| 84 if (*ar->namewhat != '\0') /* is there a name? */ |
| 85 lua_pushfstring(L, "function " LUA_QS, ar->name); |
| 86 else if (*ar->what == 'm') /* main? */ |
| 87 lua_pushliteral(L, "main chunk"); |
| 88 else if (*ar->what == 'C') { |
| 89 if (pushglobalfuncname(L, ar)) { |
| 90 lua_pushfstring(L, "function " LUA_QS, lua_tostring(L, -1)); |
| 91 lua_remove(L, -2); /* remove name */ |
| 92 } |
| 93 else |
| 94 lua_pushliteral(L, "?"); |
| 95 } |
| 96 else |
| 97 lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined); |
| 98 } |
| 99 |
| 100 |
| 101 static int countlevels (lua_State *L) { |
| 102 lua_Debug ar; |
| 103 int li = 1, le = 1; |
| 104 /* find an upper bound */ |
| 105 while (lua_getstack(L, le, &ar)) { li = le; le *= 2; } |
| 106 /* do a binary search */ |
| 107 while (li < le) { |
| 108 int m = (li + le)/2; |
| 109 if (lua_getstack(L, m, &ar)) li = m + 1; |
| 110 else le = m; |
| 111 } |
| 112 return le - 1; |
| 113 } |
| 114 |
| 115 |
| 116 LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1, |
| 117 const char *msg, int level) { |
| 118 lua_Debug ar; |
| 119 int top = lua_gettop(L); |
| 120 int numlevels = countlevels(L1); |
| 121 int mark = (numlevels > LEVELS1 + LEVELS2) ? LEVELS1 : 0; |
| 122 if (msg) lua_pushfstring(L, "%s\n", msg); |
| 123 lua_pushliteral(L, "stack traceback:"); |
| 124 while (lua_getstack(L1, level++, &ar)) { |
| 125 if (level == mark) { /* too many levels? */ |
| 126 lua_pushliteral(L, "\n\t..."); /* add a '...' */ |
| 127 level = numlevels - LEVELS2; /* and skip to last ones */ |
| 128 } |
| 129 else { |
| 130 lua_getinfo(L1, "Slnt", &ar); |
| 131 lua_pushfstring(L, "\n\t%s:", ar.short_src); |
| 132 if (ar.currentline > 0) |
| 133 lua_pushfstring(L, "%d:", ar.currentline); |
| 134 lua_pushliteral(L, " in "); |
| 135 pushfuncname(L, &ar); |
| 136 if (ar.istailcall) |
| 137 lua_pushliteral(L, "\n\t(...tail calls...)"); |
| 138 lua_concat(L, lua_gettop(L) - top); |
| 139 } |
| 140 } |
| 141 lua_concat(L, lua_gettop(L) - top); |
| 142 } |
| 143 |
| 144 /* }====================================================== */ |
| 145 |
| 146 |
| 147 /* |
| 148 ** {====================================================== |
| 149 ** Error-report functions |
| 150 ** ======================================================= |
| 151 */ |
| 152 |
| 153 LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) { |
| 154 lua_Debug ar; |
| 155 if (!lua_getstack(L, 0, &ar)) /* no stack frame? */ |
| 156 return luaL_error(L, "bad argument #%d (%s)", narg, extramsg); |
| 157 lua_getinfo(L, "n", &ar); |
| 158 if (strcmp(ar.namewhat, "method") == 0) { |
| 159 narg--; /* do not count `self' */ |
| 160 if (narg == 0) /* error is in the self argument itself? */ |
| 161 return luaL_error(L, "calling " LUA_QS " on bad self (%s)", |
| 162 ar.name, extramsg); |
| 163 } |
| 164 if (ar.name == NULL) |
| 165 ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?"; |
| 166 return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)", |
| 167 narg, ar.name, extramsg); |
| 168 } |
| 169 |
| 170 |
| 171 static int typeerror (lua_State *L, int narg, const char *tname) { |
| 172 const char *msg = lua_pushfstring(L, "%s expected, got %s", |
| 173 tname, luaL_typename(L, narg)); |
| 174 return luaL_argerror(L, narg, msg); |
| 175 } |
| 176 |
| 177 |
| 178 static void tag_error (lua_State *L, int narg, int tag) { |
| 179 typeerror(L, narg, lua_typename(L, tag)); |
| 180 } |
| 181 |
| 182 |
| 183 LUALIB_API void luaL_where (lua_State *L, int level) { |
| 184 lua_Debug ar; |
| 185 if (lua_getstack(L, level, &ar)) { /* check function at level */ |
| 186 lua_getinfo(L, "Sl", &ar); /* get info about it */ |
| 187 if (ar.currentline > 0) { /* is there info? */ |
| 188 lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline); |
| 189 return; |
| 190 } |
| 191 } |
| 192 lua_pushliteral(L, ""); /* else, no information available... */ |
| 193 } |
| 194 |
| 195 |
| 196 LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) { |
| 197 va_list argp; |
| 198 va_start(argp, fmt); |
| 199 luaL_where(L, 1); |
| 200 lua_pushvfstring(L, fmt, argp); |
| 201 va_end(argp); |
| 202 lua_concat(L, 2); |
| 203 return lua_error(L); |
| 204 } |
| 205 |
| 206 |
| 207 LUALIB_API int luaL_fileresult (lua_State *L, int stat, const char *fname) { |
| 208 int en = errno; /* calls to Lua API may change this value */ |
| 209 if (stat) { |
| 210 lua_pushboolean(L, 1); |
| 211 return 1; |
| 212 } |
| 213 else { |
| 214 lua_pushnil(L); |
| 215 if (fname) |
| 216 lua_pushfstring(L, "%s: %s", fname, strerror(en)); |
| 217 else |
| 218 lua_pushstring(L, strerror(en)); |
| 219 lua_pushinteger(L, en); |
| 220 return 3; |
| 221 } |
| 222 } |
| 223 |
| 224 |
| 225 #if !defined(inspectstat) /* { */ |
| 226 |
| 227 #if defined(LUA_USE_POSIX) |
| 228 |
| 229 #include <sys/wait.h> |
| 230 |
| 231 /* |
| 232 ** use appropriate macros to interpret 'pclose' return status |
| 233 */ |
| 234 #define inspectstat(stat,what) \ |
| 235 if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \ |
| 236 else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; } |
| 237 |
| 238 #else |
| 239 |
| 240 #define inspectstat(stat,what) /* no op */ |
| 241 |
| 242 #endif |
| 243 |
| 244 #endif /* } */ |
| 245 |
| 246 |
| 247 LUALIB_API int luaL_execresult (lua_State *L, int stat) { |
| 248 const char *what = "exit"; /* type of termination */ |
| 249 if (stat == -1) /* error? */ |
| 250 return luaL_fileresult(L, 0, NULL); |
| 251 else { |
| 252 inspectstat(stat, what); /* interpret result */ |
| 253 if (*what == 'e' && stat == 0) /* successful termination? */ |
| 254 lua_pushboolean(L, 1); |
| 255 else |
| 256 lua_pushnil(L); |
| 257 lua_pushstring(L, what); |
| 258 lua_pushinteger(L, stat); |
| 259 return 3; /* return true/nil,what,code */ |
| 260 } |
| 261 } |
| 262 |
| 263 /* }====================================================== */ |
| 264 |
| 265 |
| 266 /* |
| 267 ** {====================================================== |
| 268 ** Userdata's metatable manipulation |
| 269 ** ======================================================= |
| 270 */ |
| 271 |
| 272 LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) { |
| 273 luaL_getmetatable(L, tname); /* try to get metatable */ |
| 274 if (!lua_isnil(L, -1)) /* name already in use? */ |
| 275 return 0; /* leave previous value on top, but return 0 */ |
| 276 lua_pop(L, 1); |
| 277 lua_newtable(L); /* create metatable */ |
| 278 lua_pushvalue(L, -1); |
| 279 lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */ |
| 280 return 1; |
| 281 } |
| 282 |
| 283 |
| 284 LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) { |
| 285 luaL_getmetatable(L, tname); |
| 286 lua_setmetatable(L, -2); |
| 287 } |
| 288 |
| 289 |
| 290 LUALIB_API void *luaL_testudata (lua_State *L, int ud, const char *tname) { |
| 291 void *p = lua_touserdata(L, ud); |
| 292 if (p != NULL) { /* value is a userdata? */ |
| 293 if (lua_getmetatable(L, ud)) { /* does it have a metatable? */ |
| 294 luaL_getmetatable(L, tname); /* get correct metatable */ |
| 295 if (!lua_rawequal(L, -1, -2)) /* not the same? */ |
| 296 p = NULL; /* value is a userdata with wrong metatable */ |
| 297 lua_pop(L, 2); /* remove both metatables */ |
| 298 return p; |
| 299 } |
| 300 } |
| 301 return NULL; /* value is not a userdata with a metatable */ |
| 302 } |
| 303 |
| 304 |
| 305 LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) { |
| 306 void *p = luaL_testudata(L, ud, tname); |
| 307 if (p == NULL) typeerror(L, ud, tname); |
| 308 return p; |
| 309 } |
| 310 |
| 311 /* }====================================================== */ |
| 312 |
| 313 |
| 314 /* |
| 315 ** {====================================================== |
| 316 ** Argument check functions |
| 317 ** ======================================================= |
| 318 */ |
| 319 |
| 320 LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def, |
| 321 const char *const lst[]) { |
| 322 const char *name = (def) ? luaL_optstring(L, narg, def) : |
| 323 luaL_checkstring(L, narg); |
| 324 int i; |
| 325 for (i=0; lst[i]; i++) |
| 326 if (strcmp(lst[i], name) == 0) |
| 327 return i; |
| 328 return luaL_argerror(L, narg, |
| 329 lua_pushfstring(L, "invalid option " LUA_QS, name)); |
| 330 } |
| 331 |
| 332 |
| 333 LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) { |
| 334 /* keep some extra space to run error routines, if needed */ |
| 335 const int extra = LUA_MINSTACK; |
| 336 if (!lua_checkstack(L, space + extra)) { |
| 337 if (msg) |
| 338 luaL_error(L, "stack overflow (%s)", msg); |
| 339 else |
| 340 luaL_error(L, "stack overflow"); |
| 341 } |
| 342 } |
| 343 |
| 344 |
| 345 LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) { |
| 346 if (lua_type(L, narg) != t) |
| 347 tag_error(L, narg, t); |
| 348 } |
| 349 |
| 350 |
| 351 LUALIB_API void luaL_checkany (lua_State *L, int narg) { |
| 352 if (lua_type(L, narg) == LUA_TNONE) |
| 353 luaL_argerror(L, narg, "value expected"); |
| 354 } |
| 355 |
| 356 |
| 357 LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) { |
| 358 const char *s = lua_tolstring(L, narg, len); |
| 359 if (!s) tag_error(L, narg, LUA_TSTRING); |
| 360 return s; |
| 361 } |
| 362 |
| 363 |
| 364 LUALIB_API const char *luaL_optlstring (lua_State *L, int narg, |
| 365 const char *def, size_t *len) { |
| 366 if (lua_isnoneornil(L, narg)) { |
| 367 if (len) |
| 368 *len = (def ? strlen(def) : 0); |
| 369 return def; |
| 370 } |
| 371 else return luaL_checklstring(L, narg, len); |
| 372 } |
| 373 |
| 374 |
| 375 LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) { |
| 376 int isnum; |
| 377 lua_Number d = lua_tonumberx(L, narg, &isnum); |
| 378 if (!isnum) |
| 379 tag_error(L, narg, LUA_TNUMBER); |
| 380 return d; |
| 381 } |
| 382 |
| 383 |
| 384 LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) { |
| 385 return luaL_opt(L, luaL_checknumber, narg, def); |
| 386 } |
| 387 |
| 388 |
| 389 LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) { |
| 390 int isnum; |
| 391 lua_Integer d = lua_tointegerx(L, narg, &isnum); |
| 392 if (!isnum) |
| 393 tag_error(L, narg, LUA_TNUMBER); |
| 394 return d; |
| 395 } |
| 396 |
| 397 |
| 398 LUALIB_API lua_Unsigned luaL_checkunsigned (lua_State *L, int narg) { |
| 399 int isnum; |
| 400 lua_Unsigned d = lua_tounsignedx(L, narg, &isnum); |
| 401 if (!isnum) |
| 402 tag_error(L, narg, LUA_TNUMBER); |
| 403 return d; |
| 404 } |
| 405 |
| 406 |
| 407 LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg, |
| 408 lua_Integer def) { |
| 409 return luaL_opt(L, luaL_checkinteger, narg, def); |
| 410 } |
| 411 |
| 412 |
| 413 LUALIB_API lua_Unsigned luaL_optunsigned (lua_State *L, int narg, |
| 414 lua_Unsigned def) { |
| 415 return luaL_opt(L, luaL_checkunsigned, narg, def); |
| 416 } |
| 417 |
| 418 /* }====================================================== */ |
| 419 |
| 420 |
| 421 /* |
| 422 ** {====================================================== |
| 423 ** Generic Buffer manipulation |
| 424 ** ======================================================= |
| 425 */ |
| 426 |
| 427 /* |
| 428 ** check whether buffer is using a userdata on the stack as a temporary |
| 429 ** buffer |
| 430 */ |
| 431 #define buffonstack(B) ((B)->b != (B)->initb) |
| 432 |
| 433 |
| 434 /* |
| 435 ** returns a pointer to a free area with at least 'sz' bytes |
| 436 */ |
| 437 LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) { |
| 438 lua_State *L = B->L; |
| 439 if (B->size - B->n < sz) { /* not enough space? */ |
| 440 char *newbuff; |
| 441 size_t newsize = B->size * 2; /* double buffer size */ |
| 442 if (newsize - B->n < sz) /* not big enough? */ |
| 443 newsize = B->n + sz; |
| 444 if (newsize < B->n || newsize - B->n < sz) |
| 445 luaL_error(L, "buffer too large"); |
| 446 /* create larger buffer */ |
| 447 newbuff = (char *)lua_newuserdata(L, newsize * sizeof(char)); |
| 448 /* move content to new buffer */ |
| 449 memcpy(newbuff, B->b, B->n * sizeof(char)); |
| 450 if (buffonstack(B)) |
| 451 lua_remove(L, -2); /* remove old buffer */ |
| 452 B->b = newbuff; |
| 453 B->size = newsize; |
| 454 } |
| 455 return &B->b[B->n]; |
| 456 } |
| 457 |
| 458 |
| 459 LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) { |
| 460 char *b = luaL_prepbuffsize(B, l); |
| 461 memcpy(b, s, l * sizeof(char)); |
| 462 luaL_addsize(B, l); |
| 463 } |
| 464 |
| 465 |
| 466 LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) { |
| 467 luaL_addlstring(B, s, strlen(s)); |
| 468 } |
| 469 |
| 470 |
| 471 LUALIB_API void luaL_pushresult (luaL_Buffer *B) { |
| 472 lua_State *L = B->L; |
| 473 lua_pushlstring(L, B->b, B->n); |
| 474 if (buffonstack(B)) |
| 475 lua_remove(L, -2); /* remove old buffer */ |
| 476 } |
| 477 |
| 478 |
| 479 LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) { |
| 480 luaL_addsize(B, sz); |
| 481 luaL_pushresult(B); |
| 482 } |
| 483 |
| 484 |
| 485 LUALIB_API void luaL_addvalue (luaL_Buffer *B) { |
| 486 lua_State *L = B->L; |
| 487 size_t l; |
| 488 const char *s = lua_tolstring(L, -1, &l); |
| 489 if (buffonstack(B)) |
| 490 lua_insert(L, -2); /* put value below buffer */ |
| 491 luaL_addlstring(B, s, l); |
| 492 lua_remove(L, (buffonstack(B)) ? -2 : -1); /* remove value */ |
| 493 } |
| 494 |
| 495 |
| 496 LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { |
| 497 B->L = L; |
| 498 B->b = B->initb; |
| 499 B->n = 0; |
| 500 B->size = LUAL_BUFFERSIZE; |
| 501 } |
| 502 |
| 503 |
| 504 LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) { |
| 505 luaL_buffinit(L, B); |
| 506 return luaL_prepbuffsize(B, sz); |
| 507 } |
| 508 |
| 509 /* }====================================================== */ |
| 510 |
| 511 |
| 512 /* |
| 513 ** {====================================================== |
| 514 ** Reference system |
| 515 ** ======================================================= |
| 516 */ |
| 517 |
| 518 /* index of free-list header */ |
| 519 #define freelist 0 |
| 520 |
| 521 |
| 522 LUALIB_API int luaL_ref (lua_State *L, int t) { |
| 523 int ref; |
| 524 if (lua_isnil(L, -1)) { |
| 525 lua_pop(L, 1); /* remove from stack */ |
| 526 return LUA_REFNIL; /* `nil' has a unique fixed reference */ |
| 527 } |
| 528 t = lua_absindex(L, t); |
| 529 lua_rawgeti(L, t, freelist); /* get first free element */ |
| 530 ref = (int)lua_tointeger(L, -1); /* ref = t[freelist] */ |
| 531 lua_pop(L, 1); /* remove it from stack */ |
| 532 if (ref != 0) { /* any free element? */ |
| 533 lua_rawgeti(L, t, ref); /* remove it from list */ |
| 534 lua_rawseti(L, t, freelist); /* (t[freelist] = t[ref]) */ |
| 535 } |
| 536 else /* no free elements */ |
| 537 ref = (int)lua_rawlen(L, t) + 1; /* get a new reference */ |
| 538 lua_rawseti(L, t, ref); |
| 539 return ref; |
| 540 } |
| 541 |
| 542 |
| 543 LUALIB_API void luaL_unref (lua_State *L, int t, int ref) { |
| 544 if (ref >= 0) { |
| 545 t = lua_absindex(L, t); |
| 546 lua_rawgeti(L, t, freelist); |
| 547 lua_rawseti(L, t, ref); /* t[ref] = t[freelist] */ |
| 548 lua_pushinteger(L, ref); |
| 549 lua_rawseti(L, t, freelist); /* t[freelist] = ref */ |
| 550 } |
| 551 } |
| 552 |
| 553 /* }====================================================== */ |
| 554 |
| 555 |
| 556 /* |
| 557 ** {====================================================== |
| 558 ** Load functions |
| 559 ** ======================================================= |
| 560 */ |
| 561 |
| 562 typedef struct LoadF { |
| 563 int n; /* number of pre-read characters */ |
| 564 FILE *f; /* file being read */ |
| 565 char buff[LUAL_BUFFERSIZE]; /* area for reading file */ |
| 566 } LoadF; |
| 567 |
| 568 |
| 569 static const char *getF (lua_State *L, void *ud, size_t *size) { |
| 570 LoadF *lf = (LoadF *)ud; |
| 571 (void)L; /* not used */ |
| 572 if (lf->n > 0) { /* are there pre-read characters to be read? */ |
| 573 *size = lf->n; /* return them (chars already in buffer) */ |
| 574 lf->n = 0; /* no more pre-read characters */ |
| 575 } |
| 576 else { /* read a block from file */ |
| 577 /* 'fread' can return > 0 *and* set the EOF flag. If next call to |
| 578 'getF' called 'fread', it might still wait for user input. |
| 579 The next check avoids this problem. */ |
| 580 if (feof(lf->f)) return NULL; |
| 581 *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f); /* read block */ |
| 582 } |
| 583 return lf->buff; |
| 584 } |
| 585 |
| 586 |
| 587 static int errfile (lua_State *L, const char *what, int fnameindex) { |
| 588 const char *serr = strerror(errno); |
| 589 const char *filename = lua_tostring(L, fnameindex) + 1; |
| 590 lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr); |
| 591 lua_remove(L, fnameindex); |
| 592 return LUA_ERRFILE; |
| 593 } |
| 594 |
| 595 |
| 596 static int skipBOM (LoadF *lf) { |
| 597 const char *p = "\xEF\xBB\xBF"; /* Utf8 BOM mark */ |
| 598 int c; |
| 599 lf->n = 0; |
| 600 do { |
| 601 c = getc(lf->f); |
| 602 if (c == EOF || c != *(const unsigned char *)p++) return c; |
| 603 lf->buff[lf->n++] = c; /* to be read by the parser */ |
| 604 } while (*p != '\0'); |
| 605 lf->n = 0; /* prefix matched; discard it */ |
| 606 return getc(lf->f); /* return next character */ |
| 607 } |
| 608 |
| 609 |
| 610 /* |
| 611 ** reads the first character of file 'f' and skips an optional BOM mark |
| 612 ** in its beginning plus its first line if it starts with '#'. Returns |
| 613 ** true if it skipped the first line. In any case, '*cp' has the |
| 614 ** first "valid" character of the file (after the optional BOM and |
| 615 ** a first-line comment). |
| 616 */ |
| 617 static int skipcomment (LoadF *lf, int *cp) { |
| 618 int c = *cp = skipBOM(lf); |
| 619 if (c == '#') { /* first line is a comment (Unix exec. file)? */ |
| 620 do { /* skip first line */ |
| 621 c = getc(lf->f); |
| 622 } while (c != EOF && c != '\n') ; |
| 623 *cp = getc(lf->f); /* skip end-of-line, if present */ |
| 624 return 1; /* there was a comment */ |
| 625 } |
| 626 else return 0; /* no comment */ |
| 627 } |
| 628 |
| 629 |
| 630 LUALIB_API int luaL_loadfilex (lua_State *L, const char *filename, |
| 631 const char *mode) { |
| 632 LoadF lf; |
| 633 int status, readstatus; |
| 634 int c; |
| 635 int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */ |
| 636 if (filename == NULL) { |
| 637 lua_pushliteral(L, "=stdin"); |
| 638 lf.f = stdin; |
| 639 } |
| 640 else { |
| 641 lua_pushfstring(L, "@%s", filename); |
| 642 lf.f = fopen(filename, "r"); |
| 643 if (lf.f == NULL) return errfile(L, "open", fnameindex); |
| 644 } |
| 645 if (skipcomment(&lf, &c)) /* read initial portion */ |
| 646 lf.buff[lf.n++] = '\n'; /* add line to correct line numbers */ |
| 647 if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */ |
| 648 lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */ |
| 649 if (lf.f == NULL) return errfile(L, "reopen", fnameindex); |
| 650 skipcomment(&lf, &c); /* re-read initial portion */ |
| 651 } |
| 652 if (c != EOF) |
| 653 lf.buff[lf.n++] = c; /* 'c' is the first character of the stream */ |
| 654 status = lua_load(L, getF, &lf, lua_tostring(L, -1), mode); |
| 655 readstatus = ferror(lf.f); |
| 656 if (filename) fclose(lf.f); /* close file (even in case of errors) */ |
| 657 if (readstatus) { |
| 658 lua_settop(L, fnameindex); /* ignore results from `lua_load' */ |
| 659 return errfile(L, "read", fnameindex); |
| 660 } |
| 661 lua_remove(L, fnameindex); |
| 662 return status; |
| 663 } |
| 664 |
| 665 |
| 666 typedef struct LoadS { |
| 667 const char *s; |
| 668 size_t size; |
| 669 } LoadS; |
| 670 |
| 671 |
| 672 static const char *getS (lua_State *L, void *ud, size_t *size) { |
| 673 LoadS *ls = (LoadS *)ud; |
| 674 (void)L; /* not used */ |
| 675 if (ls->size == 0) return NULL; |
| 676 *size = ls->size; |
| 677 ls->size = 0; |
| 678 return ls->s; |
| 679 } |
| 680 |
| 681 |
| 682 LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size, |
| 683 const char *name, const char *mode) { |
| 684 LoadS ls; |
| 685 ls.s = buff; |
| 686 ls.size = size; |
| 687 return lua_load(L, getS, &ls, name, mode); |
| 688 } |
| 689 |
| 690 |
| 691 LUALIB_API int luaL_loadstring (lua_State *L, const char *s) { |
| 692 return luaL_loadbuffer(L, s, strlen(s), s); |
| 693 } |
| 694 |
| 695 /* }====================================================== */ |
| 696 |
| 697 |
| 698 |
| 699 LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) { |
| 700 if (!lua_getmetatable(L, obj)) /* no metatable? */ |
| 701 return 0; |
| 702 lua_pushstring(L, event); |
| 703 lua_rawget(L, -2); |
| 704 if (lua_isnil(L, -1)) { |
| 705 lua_pop(L, 2); /* remove metatable and metafield */ |
| 706 return 0; |
| 707 } |
| 708 else { |
| 709 lua_remove(L, -2); /* remove only metatable */ |
| 710 return 1; |
| 711 } |
| 712 } |
| 713 |
| 714 |
| 715 LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) { |
| 716 obj = lua_absindex(L, obj); |
| 717 if (!luaL_getmetafield(L, obj, event)) /* no metafield? */ |
| 718 return 0; |
| 719 lua_pushvalue(L, obj); |
| 720 lua_call(L, 1, 1); |
| 721 return 1; |
| 722 } |
| 723 |
| 724 |
| 725 LUALIB_API int luaL_len (lua_State *L, int idx) { |
| 726 int l; |
| 727 int isnum; |
| 728 lua_len(L, idx); |
| 729 l = (int)lua_tointegerx(L, -1, &isnum); |
| 730 if (!isnum) |
| 731 luaL_error(L, "object length is not a number"); |
| 732 lua_pop(L, 1); /* remove object */ |
| 733 return l; |
| 734 } |
| 735 |
| 736 |
| 737 LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) { |
| 738 if (!luaL_callmeta(L, idx, "__tostring")) { /* no metafield? */ |
| 739 switch (lua_type(L, idx)) { |
| 740 case LUA_TNUMBER: |
| 741 case LUA_TSTRING: |
| 742 lua_pushvalue(L, idx); |
| 743 break; |
| 744 case LUA_TBOOLEAN: |
| 745 lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false")); |
| 746 break; |
| 747 case LUA_TNIL: |
| 748 lua_pushliteral(L, "nil"); |
| 749 break; |
| 750 default: |
| 751 lua_pushfstring(L, "%s: %p", luaL_typename(L, idx), |
| 752 lua_topointer(L, idx)); |
| 753 break; |
| 754 } |
| 755 } |
| 756 return lua_tolstring(L, -1, len); |
| 757 } |
| 758 |
| 759 |
| 760 /* |
| 761 ** {====================================================== |
| 762 ** Compatibility with 5.1 module functions |
| 763 ** ======================================================= |
| 764 */ |
| 765 #if defined(LUA_COMPAT_MODULE) |
| 766 |
| 767 static const char *luaL_findtable (lua_State *L, int idx, |
| 768 const char *fname, int szhint) { |
| 769 const char *e; |
| 770 if (idx) lua_pushvalue(L, idx); |
| 771 do { |
| 772 e = strchr(fname, '.'); |
| 773 if (e == NULL) e = fname + strlen(fname); |
| 774 lua_pushlstring(L, fname, e - fname); |
| 775 lua_rawget(L, -2); |
| 776 if (lua_isnil(L, -1)) { /* no such field? */ |
| 777 lua_pop(L, 1); /* remove this nil */ |
| 778 lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */ |
| 779 lua_pushlstring(L, fname, e - fname); |
| 780 lua_pushvalue(L, -2); |
| 781 lua_settable(L, -4); /* set new table into field */ |
| 782 } |
| 783 else if (!lua_istable(L, -1)) { /* field has a non-table value? */ |
| 784 lua_pop(L, 2); /* remove table and value */ |
| 785 return fname; /* return problematic part of the name */ |
| 786 } |
| 787 lua_remove(L, -2); /* remove previous table */ |
| 788 fname = e + 1; |
| 789 } while (*e == '.'); |
| 790 return NULL; |
| 791 } |
| 792 |
| 793 |
| 794 /* |
| 795 ** Count number of elements in a luaL_Reg list. |
| 796 */ |
| 797 static int libsize (const luaL_Reg *l) { |
| 798 int size = 0; |
| 799 for (; l && l->name; l++) size++; |
| 800 return size; |
| 801 } |
| 802 |
| 803 |
| 804 /* |
| 805 ** Find or create a module table with a given name. The function |
| 806 ** first looks at the _LOADED table and, if that fails, try a |
| 807 ** global variable with that name. In any case, leaves on the stack |
| 808 ** the module table. |
| 809 */ |
| 810 LUALIB_API void luaL_pushmodule (lua_State *L, const char *modname, |
| 811 int sizehint) { |
| 812 luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1); /* get _LOADED table */ |
| 813 lua_getfield(L, -1, modname); /* get _LOADED[modname] */ |
| 814 if (!lua_istable(L, -1)) { /* not found? */ |
| 815 lua_pop(L, 1); /* remove previous result */ |
| 816 /* try global variable (and create one if it does not exist) */ |
| 817 lua_pushglobaltable(L); |
| 818 if (luaL_findtable(L, 0, modname, sizehint) != NULL) |
| 819 luaL_error(L, "name conflict for module " LUA_QS, modname); |
| 820 lua_pushvalue(L, -1); |
| 821 lua_setfield(L, -3, modname); /* _LOADED[modname] = new table */ |
| 822 } |
| 823 lua_remove(L, -2); /* remove _LOADED table */ |
| 824 } |
| 825 |
| 826 |
| 827 LUALIB_API void luaL_openlib (lua_State *L, const char *libname, |
| 828 const luaL_Reg *l, int nup) { |
| 829 luaL_checkversion(L); |
| 830 if (libname) { |
| 831 luaL_pushmodule(L, libname, libsize(l)); /* get/create library table */ |
| 832 lua_insert(L, -(nup + 1)); /* move library table to below upvalues */ |
| 833 } |
| 834 if (l) |
| 835 luaL_setfuncs(L, l, nup); |
| 836 else |
| 837 lua_pop(L, nup); /* remove upvalues */ |
| 838 } |
| 839 |
| 840 #endif |
| 841 /* }====================================================== */ |
| 842 |
| 843 /* |
| 844 ** set functions from list 'l' into table at top - 'nup'; each |
| 845 ** function gets the 'nup' elements at the top as upvalues. |
| 846 ** Returns with only the table at the stack. |
| 847 */ |
| 848 LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) { |
| 849 luaL_checkversion(L); |
| 850 luaL_checkstack(L, nup, "too many upvalues"); |
| 851 for (; l->name != NULL; l++) { /* fill the table with given functions */ |
| 852 int i; |
| 853 for (i = 0; i < nup; i++) /* copy upvalues to the top */ |
| 854 lua_pushvalue(L, -nup); |
| 855 lua_pushcclosure(L, l->func, nup); /* closure with those upvalues */ |
| 856 lua_setfield(L, -(nup + 2), l->name); |
| 857 } |
| 858 lua_pop(L, nup); /* remove upvalues */ |
| 859 } |
| 860 |
| 861 |
| 862 /* |
| 863 ** ensure that stack[idx][fname] has a table and push that table |
| 864 ** into the stack |
| 865 */ |
| 866 LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) { |
| 867 lua_getfield(L, idx, fname); |
| 868 if (lua_istable(L, -1)) return 1; /* table already there */ |
| 869 else { |
| 870 lua_pop(L, 1); /* remove previous result */ |
| 871 idx = lua_absindex(L, idx); |
| 872 lua_newtable(L); |
| 873 lua_pushvalue(L, -1); /* copy to be left at top */ |
| 874 lua_setfield(L, idx, fname); /* assign new table to field */ |
| 875 return 0; /* false, because did not find table there */ |
| 876 } |
| 877 } |
| 878 |
| 879 |
| 880 /* |
| 881 ** stripped-down 'require'. Calls 'openf' to open a module, |
| 882 ** registers the result in 'package.loaded' table and, if 'glb' |
| 883 ** is true, also registers the result in the global table. |
| 884 ** Leaves resulting module on the top. |
| 885 */ |
| 886 LUALIB_API void luaL_requiref (lua_State *L, const char *modname, |
| 887 lua_CFunction openf, int glb) { |
| 888 lua_pushcfunction(L, openf); |
| 889 lua_pushstring(L, modname); /* argument to open function */ |
| 890 lua_call(L, 1, 1); /* open module */ |
| 891 luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED"); |
| 892 lua_pushvalue(L, -2); /* make copy of module (call result) */ |
| 893 lua_setfield(L, -2, modname); /* _LOADED[modname] = module */ |
| 894 lua_pop(L, 1); /* remove _LOADED table */ |
| 895 if (glb) { |
| 896 lua_pushvalue(L, -1); /* copy of 'mod' */ |
| 897 lua_setglobal(L, modname); /* _G[modname] = module */ |
| 898 } |
| 899 } |
| 900 |
| 901 |
| 902 LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p, |
| 903 const char *r) { |
| 904 const char *wild; |
| 905 size_t l = strlen(p); |
| 906 luaL_Buffer b; |
| 907 luaL_buffinit(L, &b); |
| 908 while ((wild = strstr(s, p)) != NULL) { |
| 909 luaL_addlstring(&b, s, wild - s); /* push prefix */ |
| 910 luaL_addstring(&b, r); /* push replacement in place of pattern */ |
| 911 s = wild + l; /* continue after `p' */ |
| 912 } |
| 913 luaL_addstring(&b, s); /* push last suffix */ |
| 914 luaL_pushresult(&b); |
| 915 return lua_tostring(L, -1); |
| 916 } |
| 917 |
| 918 |
| 919 static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { |
| 920 (void)ud; (void)osize; /* not used */ |
| 921 if (nsize == 0) { |
| 922 free(ptr); |
| 923 return NULL; |
| 924 } |
| 925 else |
| 926 return realloc(ptr, nsize); |
| 927 } |
| 928 |
| 929 |
| 930 static int panic (lua_State *L) { |
| 931 luai_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n", |
| 932 lua_tostring(L, -1)); |
| 933 return 0; /* return to Lua to abort */ |
| 934 } |
| 935 |
| 936 |
| 937 LUALIB_API lua_State *luaL_newstate (void) { |
| 938 lua_State *L = lua_newstate(l_alloc, NULL); |
| 939 if (L) lua_atpanic(L, &panic); |
| 940 return L; |
| 941 } |
| 942 |
| 943 |
| 944 LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver) { |
| 945 const lua_Number *v = lua_version(L); |
| 946 if (v != lua_version(NULL)) |
| 947 luaL_error(L, "multiple Lua VMs detected"); |
| 948 else if (*v != ver) |
| 949 luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f", |
| 950 ver, *v); |
| 951 /* check conversions number -> integer types */ |
| 952 lua_pushnumber(L, -(lua_Number)0x1234); |
| 953 if (lua_tointeger(L, -1) != -0x1234 || |
| 954 lua_tounsigned(L, -1) != (lua_Unsigned)-0x1234) |
| 955 luaL_error(L, "bad conversion number->int;" |
| 956 " must recompile Lua with proper settings"); |
| 957 lua_pop(L, 1); |
| 958 } |
| 959 |
OLD | NEW |