1 /* $NetBSD: lauxlib.c,v 1.1.1.1 2010/10/31 11:16:54 mbalmer Exp $ */ 2 3 /* 4 ** Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp 5 ** Auxiliary functions for building Lua libraries 6 ** See Copyright Notice in lua.h 7 */ 8 9 10 #include <ctype.h> 11 #include <errno.h> 12 #include <stdarg.h> 13 #include <stdio.h> 14 #include <stdlib.h> 15 #include <string.h> 16 17 18 /* This file uses only the official API of Lua. 19 ** Any function declared here could be written as an application function. 20 */ 21 22 #define lauxlib_c 23 #define LUA_LIB 24 25 #include "lua.h" 26 27 #include "lauxlib.h" 28 29 30 #define FREELIST_REF 0 /* free list of references */ 31 32 33 /* convert a stack index to positive */ 34 #define abs_index(L, i) ((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \ 35 lua_gettop(L) + (i) + 1) 36 37 38 /* 39 ** {====================================================== 40 ** Error-report functions 41 ** ======================================================= 42 */ 43 44 45 LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) { 46 lua_Debug ar; 47 if (!lua_getstack(L, 0, &ar)) /* no stack frame? */ 48 return luaL_error(L, "bad argument #%d (%s)", narg, extramsg); 49 lua_getinfo(L, "n", &ar); 50 if (strcmp(ar.namewhat, "method") == 0) { 51 narg--; /* do not count `self' */ 52 if (narg == 0) /* error is in the self argument itself? */ 53 return luaL_error(L, "calling " LUA_QS " on bad self (%s)", 54 ar.name, extramsg); 55 } 56 if (ar.name == NULL) 57 ar.name = "?"; 58 return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)", 59 narg, ar.name, extramsg); 60 } 61 62 63 LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) { 64 const char *msg = lua_pushfstring(L, "%s expected, got %s", 65 tname, luaL_typename(L, narg)); 66 return luaL_argerror(L, narg, msg); 67 } 68 69 70 static void tag_error (lua_State *L, int narg, int tag) { 71 luaL_typerror(L, narg, lua_typename(L, tag)); 72 } 73 74 75 LUALIB_API void luaL_where (lua_State *L, int level) { 76 lua_Debug ar; 77 if (lua_getstack(L, level, &ar)) { /* check function at level */ 78 lua_getinfo(L, "Sl", &ar); /* get info about it */ 79 if (ar.currentline > 0) { /* is there info? */ 80 lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline); 81 return; 82 } 83 } 84 lua_pushliteral(L, ""); /* else, no information available... */ 85 } 86 87 88 LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) { 89 va_list argp; 90 va_start(argp, fmt); 91 luaL_where(L, 1); 92 lua_pushvfstring(L, fmt, argp); 93 va_end(argp); 94 lua_concat(L, 2); 95 return lua_error(L); 96 } 97 98 /* }====================================================== */ 99 100 101 LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def, 102 const char *const lst[]) { 103 const char *name = (def) ? luaL_optstring(L, narg, def) : 104 luaL_checkstring(L, narg); 105 int i; 106 for (i=0; lst[i]; i++) 107 if (strcmp(lst[i], name) == 0) 108 return i; 109 return luaL_argerror(L, narg, 110 lua_pushfstring(L, "invalid option " LUA_QS, name)); 111 } 112 113 114 LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) { 115 lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get registry.name */ 116 if (!lua_isnil(L, -1)) /* name already in use? */ 117 return 0; /* leave previous value on top, but return 0 */ 118 lua_pop(L, 1); 119 lua_newtable(L); /* create metatable */ 120 lua_pushvalue(L, -1); 121 lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */ 122 return 1; 123 } 124 125 126 LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) { 127 void *p = lua_touserdata(L, ud); 128 if (p != NULL) { /* value is a userdata? */ 129 if (lua_getmetatable(L, ud)) { /* does it have a metatable? */ 130 lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get correct metatable */ 131 if (lua_rawequal(L, -1, -2)) { /* does it have the correct mt? */ 132 lua_pop(L, 2); /* remove both metatables */ 133 return p; 134 } 135 } 136 } 137 luaL_typerror(L, ud, tname); /* else error */ 138 return NULL; /* to avoid warnings */ 139 } 140 141 142 LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) { 143 if (!lua_checkstack(L, space)) 144 luaL_error(L, "stack overflow (%s)", mes); 145 } 146 147 148 LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) { 149 if (lua_type(L, narg) != t) 150 tag_error(L, narg, t); 151 } 152 153 154 LUALIB_API void luaL_checkany (lua_State *L, int narg) { 155 if (lua_type(L, narg) == LUA_TNONE) 156 luaL_argerror(L, narg, "value expected"); 157 } 158 159 160 LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) { 161 const char *s = lua_tolstring(L, narg, len); 162 if (!s) tag_error(L, narg, LUA_TSTRING); 163 return s; 164 } 165 166 167 LUALIB_API const char *luaL_optlstring (lua_State *L, int narg, 168 const char *def, size_t *len) { 169 if (lua_isnoneornil(L, narg)) { 170 if (len) 171 *len = (def ? strlen(def) : 0); 172 return def; 173 } 174 else return luaL_checklstring(L, narg, len); 175 } 176 177 178 LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) { 179 lua_Number d = lua_tonumber(L, narg); 180 if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */ 181 tag_error(L, narg, LUA_TNUMBER); 182 return d; 183 } 184 185 186 LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) { 187 return luaL_opt(L, luaL_checknumber, narg, def); 188 } 189 190 191 LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) { 192 lua_Integer d = lua_tointeger(L, narg); 193 if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */ 194 tag_error(L, narg, LUA_TNUMBER); 195 return d; 196 } 197 198 199 LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg, 200 lua_Integer def) { 201 return luaL_opt(L, luaL_checkinteger, narg, def); 202 } 203 204 205 LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) { 206 if (!lua_getmetatable(L, obj)) /* no metatable? */ 207 return 0; 208 lua_pushstring(L, event); 209 lua_rawget(L, -2); 210 if (lua_isnil(L, -1)) { 211 lua_pop(L, 2); /* remove metatable and metafield */ 212 return 0; 213 } 214 else { 215 lua_remove(L, -2); /* remove only metatable */ 216 return 1; 217 } 218 } 219 220 221 LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) { 222 obj = abs_index(L, obj); 223 if (!luaL_getmetafield(L, obj, event)) /* no metafield? */ 224 return 0; 225 lua_pushvalue(L, obj); 226 lua_call(L, 1, 1); 227 return 1; 228 } 229 230 231 LUALIB_API void (luaL_register) (lua_State *L, const char *libname, 232 const luaL_Reg *l) { 233 luaI_openlib(L, libname, l, 0); 234 } 235 236 237 static int libsize (const luaL_Reg *l) { 238 int size = 0; 239 for (; l->name; l++) size++; 240 return size; 241 } 242 243 244 LUALIB_API void luaI_openlib (lua_State *L, const char *libname, 245 const luaL_Reg *l, int nup) { 246 if (libname) { 247 int size = libsize(l); 248 /* check whether lib already exists */ 249 luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1); 250 lua_getfield(L, -1, libname); /* get _LOADED[libname] */ 251 if (!lua_istable(L, -1)) { /* not found? */ 252 lua_pop(L, 1); /* remove previous result */ 253 /* try global variable (and create one if it does not exist) */ 254 if (luaL_findtable(L, LUA_GLOBALSINDEX, libname, size) != NULL) 255 luaL_error(L, "name conflict for module " LUA_QS, libname); 256 lua_pushvalue(L, -1); 257 lua_setfield(L, -3, libname); /* _LOADED[libname] = new table */ 258 } 259 lua_remove(L, -2); /* remove _LOADED table */ 260 lua_insert(L, -(nup+1)); /* move library table to below upvalues */ 261 } 262 for (; l->name; l++) { 263 int i; 264 for (i=0; i<nup; i++) /* copy upvalues to the top */ 265 lua_pushvalue(L, -nup); 266 lua_pushcclosure(L, l->func, nup); 267 lua_setfield(L, -(nup+2), l->name); 268 } 269 lua_pop(L, nup); /* remove upvalues */ 270 } 271 272 273 274 /* 275 ** {====================================================== 276 ** getn-setn: size for arrays 277 ** ======================================================= 278 */ 279 280 #if defined(LUA_COMPAT_GETN) 281 282 static int checkint (lua_State *L, int topop) { 283 int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1; 284 lua_pop(L, topop); 285 return n; 286 } 287 288 289 static void getsizes (lua_State *L) { 290 lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES"); 291 if (lua_isnil(L, -1)) { /* no `size' table? */ 292 lua_pop(L, 1); /* remove nil */ 293 lua_newtable(L); /* create it */ 294 lua_pushvalue(L, -1); /* `size' will be its own metatable */ 295 lua_setmetatable(L, -2); 296 lua_pushliteral(L, "kv"); 297 lua_setfield(L, -2, "__mode"); /* metatable(N).__mode = "kv" */ 298 lua_pushvalue(L, -1); 299 lua_setfield(L, LUA_REGISTRYINDEX, "LUA_SIZES"); /* store in register */ 300 } 301 } 302 303 304 LUALIB_API void luaL_setn (lua_State *L, int t, int n) { 305 t = abs_index(L, t); 306 lua_pushliteral(L, "n"); 307 lua_rawget(L, t); 308 if (checkint(L, 1) >= 0) { /* is there a numeric field `n'? */ 309 lua_pushliteral(L, "n"); /* use it */ 310 lua_pushinteger(L, n); 311 lua_rawset(L, t); 312 } 313 else { /* use `sizes' */ 314 getsizes(L); 315 lua_pushvalue(L, t); 316 lua_pushinteger(L, n); 317 lua_rawset(L, -3); /* sizes[t] = n */ 318 lua_pop(L, 1); /* remove `sizes' */ 319 } 320 } 321 322 323 LUALIB_API int luaL_getn (lua_State *L, int t) { 324 int n; 325 t = abs_index(L, t); 326 lua_pushliteral(L, "n"); /* try t.n */ 327 lua_rawget(L, t); 328 if ((n = checkint(L, 1)) >= 0) return n; 329 getsizes(L); /* else try sizes[t] */ 330 lua_pushvalue(L, t); 331 lua_rawget(L, -2); 332 if ((n = checkint(L, 2)) >= 0) return n; 333 return (int)lua_objlen(L, t); 334 } 335 336 #endif 337 338 /* }====================================================== */ 339 340 341 342 LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p, 343 const char *r) { 344 const char *wild; 345 size_t l = strlen(p); 346 luaL_Buffer b; 347 luaL_buffinit(L, &b); 348 while ((wild = strstr(s, p)) != NULL) { 349 luaL_addlstring(&b, s, wild - s); /* push prefix */ 350 luaL_addstring(&b, r); /* push replacement in place of pattern */ 351 s = wild + l; /* continue after `p' */ 352 } 353 luaL_addstring(&b, s); /* push last suffix */ 354 luaL_pushresult(&b); 355 return lua_tostring(L, -1); 356 } 357 358 359 LUALIB_API const char *luaL_findtable (lua_State *L, int idx, 360 const char *fname, int szhint) { 361 const char *e; 362 lua_pushvalue(L, idx); 363 do { 364 e = strchr(fname, '.'); 365 if (e == NULL) e = fname + strlen(fname); 366 lua_pushlstring(L, fname, e - fname); 367 lua_rawget(L, -2); 368 if (lua_isnil(L, -1)) { /* no such field? */ 369 lua_pop(L, 1); /* remove this nil */ 370 lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */ 371 lua_pushlstring(L, fname, e - fname); 372 lua_pushvalue(L, -2); 373 lua_settable(L, -4); /* set new table into field */ 374 } 375 else if (!lua_istable(L, -1)) { /* field has a non-table value? */ 376 lua_pop(L, 2); /* remove table and value */ 377 return fname; /* return problematic part of the name */ 378 } 379 lua_remove(L, -2); /* remove previous table */ 380 fname = e + 1; 381 } while (*e == '.'); 382 return NULL; 383 } 384 385 386 387 /* 388 ** {====================================================== 389 ** Generic Buffer manipulation 390 ** ======================================================= 391 */ 392 393 394 #define bufflen(B) ((B)->p - (B)->buffer) 395 #define bufffree(B) ((size_t)(LUAL_BUFFERSIZE - bufflen(B))) 396 397 #define LIMIT (LUA_MINSTACK/2) 398 399 400 static int emptybuffer (luaL_Buffer *B) { 401 size_t l = bufflen(B); 402 if (l == 0) return 0; /* put nothing on stack */ 403 else { 404 lua_pushlstring(B->L, B->buffer, l); 405 B->p = B->buffer; 406 B->lvl++; 407 return 1; 408 } 409 } 410 411 412 static void adjuststack (luaL_Buffer *B) { 413 if (B->lvl > 1) { 414 lua_State *L = B->L; 415 int toget = 1; /* number of levels to concat */ 416 size_t toplen = lua_strlen(L, -1); 417 do { 418 size_t l = lua_strlen(L, -(toget+1)); 419 if (B->lvl - toget + 1 >= LIMIT || toplen > l) { 420 toplen += l; 421 toget++; 422 } 423 else break; 424 } while (toget < B->lvl); 425 lua_concat(L, toget); 426 B->lvl = B->lvl - toget + 1; 427 } 428 } 429 430 431 LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) { 432 if (emptybuffer(B)) 433 adjuststack(B); 434 return B->buffer; 435 } 436 437 438 LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) { 439 while (l--) 440 luaL_addchar(B, *s++); 441 } 442 443 444 LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) { 445 luaL_addlstring(B, s, strlen(s)); 446 } 447 448 449 LUALIB_API void luaL_pushresult (luaL_Buffer *B) { 450 emptybuffer(B); 451 lua_concat(B->L, B->lvl); 452 B->lvl = 1; 453 } 454 455 456 LUALIB_API void luaL_addvalue (luaL_Buffer *B) { 457 lua_State *L = B->L; 458 size_t vl; 459 const char *s = lua_tolstring(L, -1, &vl); 460 if (vl <= bufffree(B)) { /* fit into buffer? */ 461 memcpy(B->p, s, vl); /* put it there */ 462 B->p += vl; 463 lua_pop(L, 1); /* remove from stack */ 464 } 465 else { 466 if (emptybuffer(B)) 467 lua_insert(L, -2); /* put buffer before new value */ 468 B->lvl++; /* add new value into B stack */ 469 adjuststack(B); 470 } 471 } 472 473 474 LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { 475 B->L = L; 476 B->p = B->buffer; 477 B->lvl = 0; 478 } 479 480 /* }====================================================== */ 481 482 483 LUALIB_API int luaL_ref (lua_State *L, int t) { 484 int ref; 485 t = abs_index(L, t); 486 if (lua_isnil(L, -1)) { 487 lua_pop(L, 1); /* remove from stack */ 488 return LUA_REFNIL; /* `nil' has a unique fixed reference */ 489 } 490 lua_rawgeti(L, t, FREELIST_REF); /* get first free element */ 491 ref = (int)lua_tointeger(L, -1); /* ref = t[FREELIST_REF] */ 492 lua_pop(L, 1); /* remove it from stack */ 493 if (ref != 0) { /* any free element? */ 494 lua_rawgeti(L, t, ref); /* remove it from list */ 495 lua_rawseti(L, t, FREELIST_REF); /* (t[FREELIST_REF] = t[ref]) */ 496 } 497 else { /* no free elements */ 498 ref = (int)lua_objlen(L, t); 499 ref++; /* create new reference */ 500 } 501 lua_rawseti(L, t, ref); 502 return ref; 503 } 504 505 506 LUALIB_API void luaL_unref (lua_State *L, int t, int ref) { 507 if (ref >= 0) { 508 t = abs_index(L, t); 509 lua_rawgeti(L, t, FREELIST_REF); 510 lua_rawseti(L, t, ref); /* t[ref] = t[FREELIST_REF] */ 511 lua_pushinteger(L, ref); 512 lua_rawseti(L, t, FREELIST_REF); /* t[FREELIST_REF] = ref */ 513 } 514 } 515 516 517 518 /* 519 ** {====================================================== 520 ** Load functions 521 ** ======================================================= 522 */ 523 524 typedef struct LoadF { 525 int extraline; 526 FILE *f; 527 char buff[LUAL_BUFFERSIZE]; 528 } LoadF; 529 530 531 static const char *getF (lua_State *L, void *ud, size_t *size) { 532 LoadF *lf = (LoadF *)ud; 533 (void)L; 534 if (lf->extraline) { 535 lf->extraline = 0; 536 *size = 1; 537 return "\n"; 538 } 539 if (feof(lf->f)) return NULL; 540 *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f); 541 return (*size > 0) ? lf->buff : NULL; 542 } 543 544 545 static int errfile (lua_State *L, const char *what, int fnameindex) { 546 const char *serr = strerror(errno); 547 const char *filename = lua_tostring(L, fnameindex) + 1; 548 lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr); 549 lua_remove(L, fnameindex); 550 return LUA_ERRFILE; 551 } 552 553 554 LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) { 555 LoadF lf; 556 int status, readstatus; 557 int c; 558 int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */ 559 lf.extraline = 0; 560 if (filename == NULL) { 561 lua_pushliteral(L, "=stdin"); 562 lf.f = stdin; 563 } 564 else { 565 lua_pushfstring(L, "@%s", filename); 566 lf.f = fopen(filename, "r"); 567 if (lf.f == NULL) return errfile(L, "open", fnameindex); 568 } 569 c = getc(lf.f); 570 if (c == '#') { /* Unix exec. file? */ 571 lf.extraline = 1; 572 while ((c = getc(lf.f)) != EOF && c != '\n') ; /* skip first line */ 573 if (c == '\n') c = getc(lf.f); 574 } 575 if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */ 576 lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */ 577 if (lf.f == NULL) return errfile(L, "reopen", fnameindex); 578 /* skip eventual `#!...' */ 579 while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ; 580 lf.extraline = 0; 581 } 582 ungetc(c, lf.f); 583 status = lua_load(L, getF, &lf, lua_tostring(L, -1)); 584 readstatus = ferror(lf.f); 585 if (filename) fclose(lf.f); /* close file (even in case of errors) */ 586 if (readstatus) { 587 lua_settop(L, fnameindex); /* ignore results from `lua_load' */ 588 return errfile(L, "read", fnameindex); 589 } 590 lua_remove(L, fnameindex); 591 return status; 592 } 593 594 595 typedef struct LoadS { 596 const char *s; 597 size_t size; 598 } LoadS; 599 600 601 static const char *getS (lua_State *L, void *ud, size_t *size) { 602 LoadS *ls = (LoadS *)ud; 603 (void)L; 604 if (ls->size == 0) return NULL; 605 *size = ls->size; 606 ls->size = 0; 607 return ls->s; 608 } 609 610 611 LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size, 612 const char *name) { 613 LoadS ls; 614 ls.s = buff; 615 ls.size = size; 616 return lua_load(L, getS, &ls, name); 617 } 618 619 620 LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) { 621 return luaL_loadbuffer(L, s, strlen(s), s); 622 } 623 624 625 626 /* }====================================================== */ 627 628 629 static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { 630 (void)ud; 631 (void)osize; 632 if (nsize == 0) { 633 free(ptr); 634 return NULL; 635 } 636 else 637 return realloc(ptr, nsize); 638 } 639 640 641 static int panic (lua_State *L) { 642 (void)L; /* to avoid warnings */ 643 fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n", 644 lua_tostring(L, -1)); 645 return 0; 646 } 647 648 649 LUALIB_API lua_State *luaL_newstate (void) { 650 lua_State *L = lua_newstate(l_alloc, NULL); 651 if (L) lua_atpanic(L, &panic); 652 return L; 653 } 654 655