lauxlib.cc (30495B)
1 /* 2 ** $Id: lauxlib.c,v 1.289.1.1 2017/04/19 17:20:42 roberto Exp $ 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 /* 31 ** {====================================================== 32 ** Traceback 33 ** ======================================================= 34 */ 35 36 37 #define LEVELS1 10 /* size of the first part of the stack */ 38 #define LEVELS2 11 /* size of the second part of the stack */ 39 40 41 42 /* 43 ** search for 'objidx' in table at index -1. 44 ** return 1 + string at top if find a good name. 45 */ 46 static int findfield (lua_State *L, int objidx, int level) { 47 if (level == 0 || !lua_istable(L, -1)) 48 return 0; /* not found */ 49 lua_pushnil(L); /* start 'next' loop */ 50 while (lua_next(L, -2)) { /* for each pair in table */ 51 if (lua_type(L, -2) == LUA_TSTRING) { /* ignore non-string keys */ 52 if (lua_rawequal(L, objidx, -1)) { /* found object? */ 53 lua_pop(L, 1); /* remove value (but keep name) */ 54 return 1; 55 } 56 else if (findfield(L, objidx, level - 1)) { /* try recursively */ 57 lua_remove(L, -2); /* remove table (but keep name) */ 58 lua_pushliteral(L, "."); 59 lua_insert(L, -2); /* place '.' between the two names */ 60 lua_concat(L, 3); 61 return 1; 62 } 63 } 64 lua_pop(L, 1); /* remove value */ 65 } 66 return 0; /* not found */ 67 } 68 69 70 /* 71 ** Search for a name for a function in all loaded modules 72 */ 73 static int pushglobalfuncname (lua_State *L, lua_Debug *ar) { 74 int top = lua_gettop(L); 75 lua_getinfo(L, "f", ar); /* push function */ 76 lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE); 77 if (findfield(L, top + 1, 2)) { 78 const char *name = lua_tostring(L, -1); 79 if (strncmp(name, "_G.", 3) == 0) { /* name start with '_G.'? */ 80 lua_pushstring(L, name + 3); /* push name without prefix */ 81 lua_remove(L, -2); /* remove original name */ 82 } 83 lua_copy(L, -1, top + 1); /* move name to proper place */ 84 lua_pop(L, 2); /* remove pushed values */ 85 return 1; 86 } 87 else { 88 lua_settop(L, top); /* remove function and global table */ 89 return 0; 90 } 91 } 92 93 94 static void pushfuncname (lua_State *L, lua_Debug *ar) { 95 if (pushglobalfuncname(L, ar)) { /* try first a global name */ 96 lua_pushfstring(L, "function '%s'", lua_tostring(L, -1)); 97 lua_remove(L, -2); /* remove name */ 98 } 99 else if (*ar->namewhat != '\0') /* is there a name from code? */ 100 lua_pushfstring(L, "%s '%s'", ar->namewhat, ar->name); /* use it */ 101 else if (*ar->what == 'm') /* main? */ 102 lua_pushliteral(L, "main chunk"); 103 else if (*ar->what != 'C') /* for Lua functions, use <file:line> */ 104 lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined); 105 else /* nothing left... */ 106 lua_pushliteral(L, "?"); 107 } 108 109 110 static int lastlevel (lua_State *L) { 111 lua_Debug ar; 112 int li = 1, le = 1; 113 /* find an upper bound */ 114 while (lua_getstack(L, le, &ar)) { li = le; le *= 2; } 115 /* do a binary search */ 116 while (li < le) { 117 int m = (li + le)/2; 118 if (lua_getstack(L, m, &ar)) li = m + 1; 119 else le = m; 120 } 121 return le - 1; 122 } 123 124 125 LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1, 126 const char *msg, int level) { 127 lua_Debug ar; 128 int top = lua_gettop(L); 129 int last = lastlevel(L1); 130 int n1 = (last - level > LEVELS1 + LEVELS2) ? LEVELS1 : -1; 131 if (msg) 132 lua_pushfstring(L, "%s\n", msg); 133 luaL_checkstack(L, 10, NULL); 134 lua_pushliteral(L, "stack traceback:"); 135 while (lua_getstack(L1, level++, &ar)) { 136 if (n1-- == 0) { /* too many levels? */ 137 lua_pushliteral(L, "\n\t..."); /* add a '...' */ 138 level = last - LEVELS2 + 1; /* and skip to last ones */ 139 } 140 else { 141 lua_getinfo(L1, "Slnt", &ar); 142 lua_pushfstring(L, "\n\t%s:", ar.short_src); 143 if (ar.currentline > 0) 144 lua_pushfstring(L, "%d:", ar.currentline); 145 lua_pushliteral(L, " in "); 146 pushfuncname(L, &ar); 147 if (ar.istailcall) 148 lua_pushliteral(L, "\n\t(...tail calls...)"); 149 lua_concat(L, lua_gettop(L) - top); 150 } 151 } 152 lua_concat(L, lua_gettop(L) - top); 153 } 154 155 /* }====================================================== */ 156 157 158 /* 159 ** {====================================================== 160 ** Error-report functions 161 ** ======================================================= 162 */ 163 164 LUALIB_API int luaL_argerror (lua_State *L, int arg, const char *extramsg) { 165 lua_Debug ar; 166 if (!lua_getstack(L, 0, &ar)) /* no stack frame? */ 167 return luaL_error(L, "bad argument #%d (%s)", arg, extramsg); 168 lua_getinfo(L, "n", &ar); 169 if (strcmp(ar.namewhat, "method") == 0) { 170 arg--; /* do not count 'self' */ 171 if (arg == 0) /* error is in the self argument itself? */ 172 return luaL_error(L, "calling '%s' on bad self (%s)", 173 ar.name, extramsg); 174 } 175 if (ar.name == NULL) 176 ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?"; 177 return luaL_error(L, "bad argument #%d to '%s' (%s)", 178 arg, ar.name, extramsg); 179 } 180 181 182 static int typeerror (lua_State *L, int arg, const char *tname) { 183 const char *msg; 184 const char *typearg; /* name for the type of the actual argument */ 185 if (luaL_getmetafield(L, arg, "__name") == LUA_TSTRING) 186 typearg = lua_tostring(L, -1); /* use the given type name */ 187 else if (lua_type(L, arg) == LUA_TLIGHTUSERDATA) 188 typearg = "light userdata"; /* special name for messages */ 189 else 190 typearg = luaL_typename(L, arg); /* standard name */ 191 msg = lua_pushfstring(L, "%s expected, got %s", tname, typearg); 192 return luaL_argerror(L, arg, msg); 193 } 194 195 196 static void tag_error (lua_State *L, int arg, int tag) { 197 typeerror(L, arg, lua_typename(L, tag)); 198 } 199 200 201 /* 202 ** The use of 'lua_pushfstring' ensures this function does not 203 ** need reserved stack space when called. 204 */ 205 LUALIB_API void luaL_where (lua_State *L, int level) { 206 lua_Debug ar; 207 if (lua_getstack(L, level, &ar)) { /* check function at level */ 208 lua_getinfo(L, "Sl", &ar); /* get info about it */ 209 if (ar.currentline > 0) { /* is there info? */ 210 lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline); 211 return; 212 } 213 } 214 lua_pushfstring(L, ""); /* else, no information available... */ 215 } 216 217 218 /* 219 ** Again, the use of 'lua_pushvfstring' ensures this function does 220 ** not need reserved stack space when called. (At worst, it generates 221 ** an error with "stack overflow" instead of the given message.) 222 */ 223 LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) { 224 va_list argp; 225 va_start(argp, fmt); 226 luaL_where(L, 1); 227 lua_pushvfstring(L, fmt, argp); 228 va_end(argp); 229 lua_concat(L, 2); 230 return lua_error(L); 231 } 232 233 234 LUALIB_API int luaL_fileresult (lua_State *L, int stat, const char *fname) { 235 int en = errno; /* calls to Lua API may change this value */ 236 if (stat) { 237 lua_pushboolean(L, 1); 238 return 1; 239 } 240 else { 241 lua_pushnil(L); 242 if (fname) 243 lua_pushfstring(L, "%s: %s", fname, strerror(en)); 244 else 245 lua_pushstring(L, strerror(en)); 246 lua_pushinteger(L, en); 247 return 3; 248 } 249 } 250 251 252 #if !defined(l_inspectstat) /* { */ 253 254 #if defined(LUA_USE_POSIX) 255 256 #include <sys/wait.h> 257 258 /* 259 ** use appropriate macros to interpret 'pclose' return status 260 */ 261 #define l_inspectstat(stat,what) \ 262 if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \ 263 else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; } 264 265 #else 266 267 #define l_inspectstat(stat,what) /* no op */ 268 269 #endif 270 271 #endif /* } */ 272 273 274 LUALIB_API int luaL_execresult (lua_State *L, int stat) { 275 const char *what = "exit"; /* type of termination */ 276 if (stat == -1) /* error? */ 277 return luaL_fileresult(L, 0, NULL); 278 else { 279 l_inspectstat(stat, what); /* interpret result */ 280 if (*what == 'e' && stat == 0) /* successful termination? */ 281 lua_pushboolean(L, 1); 282 else 283 lua_pushnil(L); 284 lua_pushstring(L, what); 285 lua_pushinteger(L, stat); 286 return 3; /* return true/nil,what,code */ 287 } 288 } 289 290 /* }====================================================== */ 291 292 293 /* 294 ** {====================================================== 295 ** Userdata's metatable manipulation 296 ** ======================================================= 297 */ 298 299 LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) { 300 if (luaL_getmetatable(L, tname) != LUA_TNIL) /* name already in use? */ 301 return 0; /* leave previous value on top, but return 0 */ 302 lua_pop(L, 1); 303 lua_createtable(L, 0, 2); /* create metatable */ 304 lua_pushstring(L, tname); 305 lua_setfield(L, -2, "__name"); /* metatable.__name = tname */ 306 lua_pushvalue(L, -1); 307 lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */ 308 return 1; 309 } 310 311 312 LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) { 313 luaL_getmetatable(L, tname); 314 lua_setmetatable(L, -2); 315 } 316 317 318 LUALIB_API void *luaL_testudata (lua_State *L, int ud, const char *tname) { 319 void *p = lua_touserdata(L, ud); 320 if (p != NULL) { /* value is a userdata? */ 321 if (lua_getmetatable(L, ud)) { /* does it have a metatable? */ 322 luaL_getmetatable(L, tname); /* get correct metatable */ 323 if (!lua_rawequal(L, -1, -2)) /* not the same? */ 324 p = NULL; /* value is a userdata with wrong metatable */ 325 lua_pop(L, 2); /* remove both metatables */ 326 return p; 327 } 328 } 329 return NULL; /* value is not a userdata with a metatable */ 330 } 331 332 333 LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) { 334 void *p = luaL_testudata(L, ud, tname); 335 if (p == NULL) typeerror(L, ud, tname); 336 return p; 337 } 338 339 /* }====================================================== */ 340 341 342 /* 343 ** {====================================================== 344 ** Argument check functions 345 ** ======================================================= 346 */ 347 348 LUALIB_API int luaL_checkoption (lua_State *L, int arg, const char *def, 349 const char *const lst[]) { 350 const char *name = (def) ? luaL_optstring(L, arg, def) : 351 luaL_checkstring(L, arg); 352 int i; 353 for (i=0; lst[i]; i++) 354 if (strcmp(lst[i], name) == 0) 355 return i; 356 return luaL_argerror(L, arg, 357 lua_pushfstring(L, "invalid option '%s'", name)); 358 } 359 360 361 /* 362 ** Ensures the stack has at least 'space' extra slots, raising an error 363 ** if it cannot fulfill the request. (The error handling needs a few 364 ** extra slots to format the error message. In case of an error without 365 ** this extra space, Lua will generate the same 'stack overflow' error, 366 ** but without 'msg'.) 367 */ 368 LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) { 369 if (!lua_checkstack(L, space)) { 370 if (msg) 371 luaL_error(L, "stack overflow (%s)", msg); 372 else 373 luaL_error(L, "stack overflow"); 374 } 375 } 376 377 378 LUALIB_API void luaL_checktype (lua_State *L, int arg, int t) { 379 if (lua_type(L, arg) != t) 380 tag_error(L, arg, t); 381 } 382 383 384 LUALIB_API void luaL_checkany (lua_State *L, int arg) { 385 if (lua_type(L, arg) == LUA_TNONE) 386 luaL_argerror(L, arg, "value expected"); 387 } 388 389 390 LUALIB_API const char *luaL_checklstring (lua_State *L, int arg, size_t *len) { 391 const char *s = lua_tolstring(L, arg, len); 392 if (!s) tag_error(L, arg, LUA_TSTRING); 393 return s; 394 } 395 396 397 LUALIB_API const char *luaL_optlstring (lua_State *L, int arg, 398 const char *def, size_t *len) { 399 if (lua_isnoneornil(L, arg)) { 400 if (len) 401 *len = (def ? strlen(def) : 0); 402 return def; 403 } 404 else return luaL_checklstring(L, arg, len); 405 } 406 407 408 LUALIB_API lua_Number luaL_checknumber (lua_State *L, int arg) { 409 int isnum; 410 lua_Number d = lua_tonumberx(L, arg, &isnum); 411 if (!isnum) 412 tag_error(L, arg, LUA_TNUMBER); 413 return d; 414 } 415 416 417 LUALIB_API lua_Number luaL_optnumber (lua_State *L, int arg, lua_Number def) { 418 return luaL_opt(L, luaL_checknumber, arg, def); 419 } 420 421 422 static void interror (lua_State *L, int arg) { 423 if (lua_isnumber(L, arg)) 424 luaL_argerror(L, arg, "number has no integer representation"); 425 else 426 tag_error(L, arg, LUA_TNUMBER); 427 } 428 429 430 LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int arg) { 431 int isnum; 432 lua_Integer d = lua_tointegerx(L, arg, &isnum); 433 if (!isnum) { 434 interror(L, arg); 435 } 436 return d; 437 } 438 439 440 LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int arg, 441 lua_Integer def) { 442 return luaL_opt(L, luaL_checkinteger, arg, def); 443 } 444 445 /* }====================================================== */ 446 447 448 /* 449 ** {====================================================== 450 ** Generic Buffer manipulation 451 ** ======================================================= 452 */ 453 454 /* userdata to box arbitrary data */ 455 typedef struct UBox { 456 void *box; 457 size_t bsize; 458 } UBox; 459 460 461 static void *resizebox (lua_State *L, int idx, size_t newsize) { 462 void *ud; 463 lua_Alloc allocf = lua_getallocf(L, &ud); 464 UBox *box = (UBox *)lua_touserdata(L, idx); 465 void *temp = allocf(ud, box->box, box->bsize, newsize); 466 if (temp == NULL && newsize > 0) { /* allocation error? */ 467 resizebox(L, idx, 0); /* free buffer */ 468 luaL_error(L, "not enough memory for buffer allocation"); 469 } 470 box->box = temp; 471 box->bsize = newsize; 472 return temp; 473 } 474 475 476 static int boxgc (lua_State *L) { 477 resizebox(L, 1, 0); 478 return 0; 479 } 480 481 482 static void *newbox (lua_State *L, size_t newsize) { 483 UBox *box = (UBox *)lua_newuserdata(L, sizeof(UBox)); 484 box->box = NULL; 485 box->bsize = 0; 486 if (luaL_newmetatable(L, "LUABOX")) { /* creating metatable? */ 487 lua_pushcfunction(L, boxgc); 488 lua_setfield(L, -2, "__gc"); /* metatable.__gc = boxgc */ 489 } 490 lua_setmetatable(L, -2); 491 return resizebox(L, -1, newsize); 492 } 493 494 495 /* 496 ** check whether buffer is using a userdata on the stack as a temporary 497 ** buffer 498 */ 499 #define buffonstack(B) ((B)->b != (B)->initb) 500 501 502 /* 503 ** returns a pointer to a free area with at least 'sz' bytes 504 */ 505 LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) { 506 lua_State *L = B->L; 507 if (B->size - B->n < sz) { /* not enough space? */ 508 char *newbuff; 509 size_t newsize = B->size * 2; /* double buffer size */ 510 if (newsize - B->n < sz) /* not big enough? */ 511 newsize = B->n + sz; 512 if (newsize < B->n || newsize - B->n < sz) 513 luaL_error(L, "buffer too large"); 514 /* create larger buffer */ 515 if (buffonstack(B)) 516 newbuff = (char *)resizebox(L, -1, newsize); 517 else { /* no buffer yet */ 518 newbuff = (char *)newbox(L, newsize); 519 memcpy(newbuff, B->b, B->n * sizeof(char)); /* copy original content */ 520 } 521 B->b = newbuff; 522 B->size = newsize; 523 } 524 return &B->b[B->n]; 525 } 526 527 528 LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) { 529 if (l > 0) { /* avoid 'memcpy' when 's' can be NULL */ 530 char *b = luaL_prepbuffsize(B, l); 531 memcpy(b, s, l * sizeof(char)); 532 luaL_addsize(B, l); 533 } 534 } 535 536 537 LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) { 538 luaL_addlstring(B, s, strlen(s)); 539 } 540 541 542 LUALIB_API void luaL_pushresult (luaL_Buffer *B) { 543 lua_State *L = B->L; 544 lua_pushlstring(L, B->b, B->n); 545 if (buffonstack(B)) { 546 resizebox(L, -2, 0); /* delete old buffer */ 547 lua_remove(L, -2); /* remove its header from the stack */ 548 } 549 } 550 551 552 LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) { 553 luaL_addsize(B, sz); 554 luaL_pushresult(B); 555 } 556 557 558 LUALIB_API void luaL_addvalue (luaL_Buffer *B) { 559 lua_State *L = B->L; 560 size_t l; 561 const char *s = lua_tolstring(L, -1, &l); 562 if (buffonstack(B)) 563 lua_insert(L, -2); /* put value below buffer */ 564 luaL_addlstring(B, s, l); 565 lua_remove(L, (buffonstack(B)) ? -2 : -1); /* remove value */ 566 } 567 568 569 LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { 570 B->L = L; 571 B->b = B->initb; 572 B->n = 0; 573 B->size = LUAL_BUFFERSIZE; 574 } 575 576 577 LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) { 578 luaL_buffinit(L, B); 579 return luaL_prepbuffsize(B, sz); 580 } 581 582 /* }====================================================== */ 583 584 585 /* 586 ** {====================================================== 587 ** Reference system 588 ** ======================================================= 589 */ 590 591 /* index of free-list header */ 592 #define freelist 0 593 594 595 LUALIB_API int luaL_ref (lua_State *L, int t) { 596 int ref; 597 if (lua_isnil(L, -1)) { 598 lua_pop(L, 1); /* remove from stack */ 599 return LUA_REFNIL; /* 'nil' has a unique fixed reference */ 600 } 601 t = lua_absindex(L, t); 602 lua_rawgeti(L, t, freelist); /* get first free element */ 603 ref = (int)lua_tointeger(L, -1); /* ref = t[freelist] */ 604 lua_pop(L, 1); /* remove it from stack */ 605 if (ref != 0) { /* any free element? */ 606 lua_rawgeti(L, t, ref); /* remove it from list */ 607 lua_rawseti(L, t, freelist); /* (t[freelist] = t[ref]) */ 608 } 609 else /* no free elements */ 610 ref = (int)lua_rawlen(L, t) + 1; /* get a new reference */ 611 lua_rawseti(L, t, ref); 612 return ref; 613 } 614 615 616 LUALIB_API void luaL_unref (lua_State *L, int t, int ref) { 617 if (ref >= 0) { 618 t = lua_absindex(L, t); 619 lua_rawgeti(L, t, freelist); 620 lua_rawseti(L, t, ref); /* t[ref] = t[freelist] */ 621 lua_pushinteger(L, ref); 622 lua_rawseti(L, t, freelist); /* t[freelist] = ref */ 623 } 624 } 625 626 /* }====================================================== */ 627 628 629 /* 630 ** {====================================================== 631 ** Load functions 632 ** ======================================================= 633 */ 634 635 typedef struct LoadF { 636 int n; /* number of pre-read characters */ 637 FILE *f; /* file being read */ 638 char buff[BUFSIZ]; /* area for reading file */ 639 } LoadF; 640 641 642 static const char *getF (lua_State *L, void *ud, size_t *size) { 643 LoadF *lf = (LoadF *)ud; 644 (void)L; /* not used */ 645 if (lf->n > 0) { /* are there pre-read characters to be read? */ 646 *size = lf->n; /* return them (chars already in buffer) */ 647 lf->n = 0; /* no more pre-read characters */ 648 } 649 else { /* read a block from file */ 650 /* 'fread' can return > 0 *and* set the EOF flag. If next call to 651 'getF' called 'fread', it might still wait for user input. 652 The next check avoids this problem. */ 653 if (feof(lf->f)) return NULL; 654 *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f); /* read block */ 655 } 656 return lf->buff; 657 } 658 659 660 static int errfile (lua_State *L, const char *what, int fnameindex) { 661 const char *serr = strerror(errno); 662 const char *filename = lua_tostring(L, fnameindex) + 1; 663 lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr); 664 lua_remove(L, fnameindex); 665 return LUA_ERRFILE; 666 } 667 668 669 static int skipBOM (LoadF *lf) { 670 const char *p = "\xEF\xBB\xBF"; /* UTF-8 BOM mark */ 671 int c; 672 lf->n = 0; 673 do { 674 c = getc(lf->f); 675 if (c == EOF || c != *(const unsigned char *)p++) return c; 676 lf->buff[lf->n++] = c; /* to be read by the parser */ 677 } while (*p != '\0'); 678 lf->n = 0; /* prefix matched; discard it */ 679 return getc(lf->f); /* return next character */ 680 } 681 682 683 /* 684 ** reads the first character of file 'f' and skips an optional BOM mark 685 ** in its beginning plus its first line if it starts with '#'. Returns 686 ** true if it skipped the first line. In any case, '*cp' has the 687 ** first "valid" character of the file (after the optional BOM and 688 ** a first-line comment). 689 */ 690 static int skipcomment (LoadF *lf, int *cp) { 691 int c = *cp = skipBOM(lf); 692 if (c == '#') { /* first line is a comment (Unix exec. file)? */ 693 do { /* skip first line */ 694 c = getc(lf->f); 695 } while (c != EOF && c != '\n'); 696 *cp = getc(lf->f); /* skip end-of-line, if present */ 697 return 1; /* there was a comment */ 698 } 699 else return 0; /* no comment */ 700 } 701 702 703 LUALIB_API int luaL_loadfilex (lua_State *L, const char *filename, 704 const char *mode) { 705 LoadF lf; 706 int status, readstatus; 707 int c; 708 int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */ 709 if (filename == NULL) { 710 lua_pushliteral(L, "=stdin"); 711 lf.f = stdin; 712 } 713 else { 714 lua_pushfstring(L, "@%s", filename); 715 lf.f = fopen(filename, "r"); 716 if (lf.f == NULL) return errfile(L, "open", fnameindex); 717 } 718 if (skipcomment(&lf, &c)) /* read initial portion */ 719 lf.buff[lf.n++] = '\n'; /* add line to correct line numbers */ 720 if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */ 721 lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */ 722 if (lf.f == NULL) return errfile(L, "reopen", fnameindex); 723 skipcomment(&lf, &c); /* re-read initial portion */ 724 } 725 if (c != EOF) 726 lf.buff[lf.n++] = c; /* 'c' is the first character of the stream */ 727 status = lua_load(L, getF, &lf, lua_tostring(L, -1), mode); 728 readstatus = ferror(lf.f); 729 if (filename) fclose(lf.f); /* close file (even in case of errors) */ 730 if (readstatus) { 731 lua_settop(L, fnameindex); /* ignore results from 'lua_load' */ 732 return errfile(L, "read", fnameindex); 733 } 734 lua_remove(L, fnameindex); 735 return status; 736 } 737 738 739 typedef struct LoadS { 740 const char *s; 741 size_t size; 742 } LoadS; 743 744 745 static const char *getS (lua_State *L, void *ud, size_t *size) { 746 LoadS *ls = (LoadS *)ud; 747 (void)L; /* not used */ 748 if (ls->size == 0) return NULL; 749 *size = ls->size; 750 ls->size = 0; 751 return ls->s; 752 } 753 754 755 LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size, 756 const char *name, const char *mode) { 757 LoadS ls; 758 ls.s = buff; 759 ls.size = size; 760 return lua_load(L, getS, &ls, name, mode); 761 } 762 763 764 LUALIB_API int luaL_loadstring (lua_State *L, const char *s) { 765 return luaL_loadbuffer(L, s, strlen(s), s); 766 } 767 768 /* }====================================================== */ 769 770 771 772 LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) { 773 if (!lua_getmetatable(L, obj)) /* no metatable? */ 774 return LUA_TNIL; 775 else { 776 int tt; 777 lua_pushstring(L, event); 778 tt = lua_rawget(L, -2); 779 if (tt == LUA_TNIL) /* is metafield nil? */ 780 lua_pop(L, 2); /* remove metatable and metafield */ 781 else 782 lua_remove(L, -2); /* remove only metatable */ 783 return tt; /* return metafield type */ 784 } 785 } 786 787 788 LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) { 789 obj = lua_absindex(L, obj); 790 if (luaL_getmetafield(L, obj, event) == LUA_TNIL) /* no metafield? */ 791 return 0; 792 lua_pushvalue(L, obj); 793 lua_call(L, 1, 1); 794 return 1; 795 } 796 797 798 LUALIB_API lua_Integer luaL_len (lua_State *L, int idx) { 799 lua_Integer l; 800 int isnum; 801 lua_len(L, idx); 802 l = lua_tointegerx(L, -1, &isnum); 803 if (!isnum) 804 luaL_error(L, "object length is not an integer"); 805 lua_pop(L, 1); /* remove object */ 806 return l; 807 } 808 809 810 LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) { 811 if (luaL_callmeta(L, idx, "__tostring")) { /* metafield? */ 812 if (!lua_isstring(L, -1)) 813 luaL_error(L, "'__tostring' must return a string"); 814 } 815 else { 816 switch (lua_type(L, idx)) { 817 case LUA_TNUMBER: { 818 if (lua_isinteger(L, idx)) 819 lua_pushfstring(L, "%I", (LUAI_UACINT)lua_tointeger(L, idx)); 820 else 821 lua_pushfstring(L, "%f", (LUAI_UACNUMBER)lua_tonumber(L, idx)); 822 break; 823 } 824 case LUA_TSTRING: 825 lua_pushvalue(L, idx); 826 break; 827 case LUA_TBOOLEAN: 828 lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false")); 829 break; 830 case LUA_TNIL: 831 lua_pushliteral(L, "nil"); 832 break; 833 default: { 834 int tt = luaL_getmetafield(L, idx, "__name"); /* try name */ 835 const char *kind = (tt == LUA_TSTRING) ? lua_tostring(L, -1) : 836 luaL_typename(L, idx); 837 lua_pushfstring(L, "%s: %p", kind, lua_topointer(L, idx)); 838 if (tt != LUA_TNIL) 839 lua_remove(L, -2); /* remove '__name' */ 840 break; 841 } 842 } 843 } 844 return lua_tolstring(L, -1, len); 845 } 846 847 848 /* 849 ** {====================================================== 850 ** Compatibility with 5.1 module functions 851 ** ======================================================= 852 */ 853 #if defined(LUA_COMPAT_MODULE) 854 855 static const char *luaL_findtable (lua_State *L, int idx, 856 const char *fname, int szhint) { 857 const char *e; 858 if (idx) lua_pushvalue(L, idx); 859 do { 860 e = strchr(fname, '.'); 861 if (e == NULL) e = fname + strlen(fname); 862 lua_pushlstring(L, fname, e - fname); 863 if (lua_rawget(L, -2) == LUA_TNIL) { /* no such field? */ 864 lua_pop(L, 1); /* remove this nil */ 865 lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */ 866 lua_pushlstring(L, fname, e - fname); 867 lua_pushvalue(L, -2); 868 lua_settable(L, -4); /* set new table into field */ 869 } 870 else if (!lua_istable(L, -1)) { /* field has a non-table value? */ 871 lua_pop(L, 2); /* remove table and value */ 872 return fname; /* return problematic part of the name */ 873 } 874 lua_remove(L, -2); /* remove previous table */ 875 fname = e + 1; 876 } while (*e == '.'); 877 return NULL; 878 } 879 880 881 /* 882 ** Count number of elements in a luaL_Reg list. 883 */ 884 static int libsize (const luaL_Reg *l) { 885 int size = 0; 886 for (; l && l->name; l++) size++; 887 return size; 888 } 889 890 891 /* 892 ** Find or create a module table with a given name. The function 893 ** first looks at the LOADED table and, if that fails, try a 894 ** global variable with that name. In any case, leaves on the stack 895 ** the module table. 896 */ 897 LUALIB_API void luaL_pushmodule (lua_State *L, const char *modname, 898 int sizehint) { 899 luaL_findtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE, 1); 900 if (lua_getfield(L, -1, modname) != LUA_TTABLE) { /* no LOADED[modname]? */ 901 lua_pop(L, 1); /* remove previous result */ 902 /* try global variable (and create one if it does not exist) */ 903 lua_pushglobaltable(L); 904 if (luaL_findtable(L, 0, modname, sizehint) != NULL) 905 luaL_error(L, "name conflict for module '%s'", modname); 906 lua_pushvalue(L, -1); 907 lua_setfield(L, -3, modname); /* LOADED[modname] = new table */ 908 } 909 lua_remove(L, -2); /* remove LOADED table */ 910 } 911 912 913 LUALIB_API void luaL_openlib (lua_State *L, const char *libname, 914 const luaL_Reg *l, int nup) { 915 luaL_checkversion(L); 916 if (libname) { 917 luaL_pushmodule(L, libname, libsize(l)); /* get/create library table */ 918 lua_insert(L, -(nup + 1)); /* move library table to below upvalues */ 919 } 920 if (l) 921 luaL_setfuncs(L, l, nup); 922 else 923 lua_pop(L, nup); /* remove upvalues */ 924 } 925 926 #endif 927 /* }====================================================== */ 928 929 /* 930 ** set functions from list 'l' into table at top - 'nup'; each 931 ** function gets the 'nup' elements at the top as upvalues. 932 ** Returns with only the table at the stack. 933 */ 934 LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) { 935 luaL_checkstack(L, nup, "too many upvalues"); 936 for (; l->name != NULL; l++) { /* fill the table with given functions */ 937 int i; 938 for (i = 0; i < nup; i++) /* copy upvalues to the top */ 939 lua_pushvalue(L, -nup); 940 lua_pushcclosure(L, l->func, nup); /* closure with those upvalues */ 941 lua_setfield(L, -(nup + 2), l->name); 942 } 943 lua_pop(L, nup); /* remove upvalues */ 944 } 945 946 947 /* 948 ** ensure that stack[idx][fname] has a table and push that table 949 ** into the stack 950 */ 951 LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) { 952 if (lua_getfield(L, idx, fname) == LUA_TTABLE) 953 return 1; /* table already there */ 954 else { 955 lua_pop(L, 1); /* remove previous result */ 956 idx = lua_absindex(L, idx); 957 lua_newtable(L); 958 lua_pushvalue(L, -1); /* copy to be left at top */ 959 lua_setfield(L, idx, fname); /* assign new table to field */ 960 return 0; /* false, because did not find table there */ 961 } 962 } 963 964 965 /* 966 ** Stripped-down 'require': After checking "loaded" table, calls 'openf' 967 ** to open a module, registers the result in 'package.loaded' table and, 968 ** if 'glb' is true, also registers the result in the global table. 969 ** Leaves resulting module on the top. 970 */ 971 LUALIB_API void luaL_requiref (lua_State *L, const char *modname, 972 lua_CFunction openf, int glb) { 973 luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE); 974 lua_getfield(L, -1, modname); /* LOADED[modname] */ 975 if (!lua_toboolean(L, -1)) { /* package not already loaded? */ 976 lua_pop(L, 1); /* remove field */ 977 lua_pushcfunction(L, openf); 978 lua_pushstring(L, modname); /* argument to open function */ 979 lua_call(L, 1, 1); /* call 'openf' to open module */ 980 lua_pushvalue(L, -1); /* make copy of module (call result) */ 981 lua_setfield(L, -3, modname); /* LOADED[modname] = module */ 982 } 983 lua_remove(L, -2); /* remove LOADED table */ 984 if (glb) { 985 lua_pushvalue(L, -1); /* copy of module */ 986 lua_setglobal(L, modname); /* _G[modname] = module */ 987 } 988 } 989 990 991 LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p, 992 const char *r) { 993 const char *wild; 994 size_t l = strlen(p); 995 luaL_Buffer b; 996 luaL_buffinit(L, &b); 997 while ((wild = strstr(s, p)) != NULL) { 998 luaL_addlstring(&b, s, wild - s); /* push prefix */ 999 luaL_addstring(&b, r); /* push replacement in place of pattern */ 1000 s = wild + l; /* continue after 'p' */ 1001 } 1002 luaL_addstring(&b, s); /* push last suffix */ 1003 luaL_pushresult(&b); 1004 return lua_tostring(L, -1); 1005 } 1006 1007 1008 static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { 1009 (void)ud; (void)osize; /* not used */ 1010 if (nsize == 0) { 1011 free(ptr); 1012 return NULL; 1013 } 1014 else 1015 return realloc(ptr, nsize); 1016 } 1017 1018 1019 static int panic (lua_State *L) { 1020 lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n", 1021 lua_tostring(L, -1)); 1022 return 0; /* return to Lua to abort */ 1023 } 1024 1025 1026 LUALIB_API lua_State *luaL_newstate (void) { 1027 lua_State *L = lua_newstate(l_alloc, NULL); 1028 if (L) lua_atpanic(L, &panic); 1029 return L; 1030 } 1031 1032 1033 LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver, size_t sz) { 1034 const lua_Number *v = lua_version(L); 1035 if (sz != LUAL_NUMSIZES) /* check numeric types */ 1036 luaL_error(L, "core and library have incompatible numeric types"); 1037 if (v != lua_version(NULL)) 1038 luaL_error(L, "multiple Lua VMs detected"); 1039 else if (*v != ver) 1040 luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f", 1041 (LUAI_UACNUMBER)ver, (LUAI_UACNUMBER)*v); 1042 } 1043