1 /* 2 ** $Id: lbaselib.c,v 1.276 2013/02/21 13:44:53 roberto Exp $ 3 ** Basic library 4 ** See Copyright Notice in lua.h 5 */ 6 7 8 9 #include <ctype.h> 10 #include <stdio.h> 11 #include <stdlib.h> 12 #include <string.h> 13 14 #define lbaselib_c 15 #define LUA_LIB 16 17 #include "lua.h" 18 19 #include "lauxlib.h" 20 #include "lualib.h" 21 22 23 static int luaB_print (lua_State *L) { 24 int n = lua_gettop(L); /* number of arguments */ 25 int i; 26 lua_getglobal(L, "tostring"); 27 for (i=1; i<=n; i++) { 28 const char *s; 29 size_t l; 30 lua_pushvalue(L, -1); /* function to be called */ 31 lua_pushvalue(L, i); /* value to print */ 32 lua_call(L, 1, 1); 33 s = lua_tolstring(L, -1, &l); /* get result */ 34 if (s == NULL) 35 return luaL_error(L, 36 LUA_QL("tostring") " must return a string to " LUA_QL("print")); 37 if (i>1) luai_writestring("\t", 1); 38 luai_writestring(s, l); 39 lua_pop(L, 1); /* pop result */ 40 } 41 luai_writeline(); 42 return 0; 43 } 44 45 46 #define SPACECHARS " \f\n\r\t\v" 47 48 static int luaB_tonumber (lua_State *L) { 49 if (lua_isnoneornil(L, 2)) { /* standard conversion */ 50 int isnum; 51 lua_Number n = lua_tonumberx(L, 1, &isnum); 52 if (isnum) { 53 lua_pushnumber(L, n); 54 return 1; 55 } /* else not a number; must be something */ 56 luaL_checkany(L, 1); 57 } 58 else { 59 size_t l; 60 const char *s = luaL_checklstring(L, 1, &l); 61 const char *e = s + l; /* end point for 's' */ 62 int base = luaL_checkint(L, 2); 63 int neg = 0; 64 luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range"); 65 s += strspn(s, SPACECHARS); /* skip initial spaces */ 66 if (*s == '-') { s++; neg = 1; } /* handle signal */ 67 else if (*s == '+') s++; 68 if (isalnum((unsigned char)*s)) { 69 lua_Number n = 0; 70 do { 71 int digit = (isdigit((unsigned char)*s)) ? *s - '0' 72 : toupper((unsigned char)*s) - 'A' + 10; 73 if (digit >= base) break; /* invalid numeral; force a fail */ 74 n = n * (lua_Number)base + (lua_Number)digit; 75 s++; 76 } while (isalnum((unsigned char)*s)); 77 s += strspn(s, SPACECHARS); /* skip trailing spaces */ 78 if (s == e) { /* no invalid trailing characters? */ 79 lua_pushnumber(L, (neg) ? -n : n); 80 return 1; 81 } /* else not a number */ 82 } /* else not a number */ 83 } 84 lua_pushnil(L); /* not a number */ 85 return 1; 86 } 87 88 89 static int luaB_error (lua_State *L) { 90 int level = luaL_optint(L, 2, 1); 91 lua_settop(L, 1); 92 if (lua_isstring(L, 1) && level > 0) { /* add extra information? */ 93 luaL_where(L, level); 94 lua_pushvalue(L, 1); 95 lua_concat(L, 2); 96 } 97 return lua_error(L); 98 } 99 100 101 static int luaB_getmetatable (lua_State *L) { 102 luaL_checkany(L, 1); 103 if (!lua_getmetatable(L, 1)) { 104 lua_pushnil(L); 105 return 1; /* no metatable */ 106 } 107 luaL_getmetafield(L, 1, "__metatable"); 108 return 1; /* returns either __metatable field (if present) or metatable */ 109 } 110 111 112 static int luaB_setmetatable (lua_State *L) { 113 int t = lua_type(L, 2); 114 luaL_checktype(L, 1, LUA_TTABLE); 115 luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2, 116 "nil or table expected"); 117 if (luaL_getmetafield(L, 1, "__metatable")) 118 return luaL_error(L, "cannot change a protected metatable"); 119 lua_settop(L, 2); 120 lua_setmetatable(L, 1); 121 return 1; 122 } 123 124 125 static int luaB_rawequal (lua_State *L) { 126 luaL_checkany(L, 1); 127 luaL_checkany(L, 2); 128 lua_pushboolean(L, lua_rawequal(L, 1, 2)); 129 return 1; 130 } 131 132 133 static int luaB_rawlen (lua_State *L) { 134 int t = lua_type(L, 1); 135 luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1, 136 "table or string expected"); 137 lua_pushinteger(L, lua_rawlen(L, 1)); 138 return 1; 139 } 140 141 142 static int luaB_rawget (lua_State *L) { 143 luaL_checktype(L, 1, LUA_TTABLE); 144 luaL_checkany(L, 2); 145 lua_settop(L, 2); 146 lua_rawget(L, 1); 147 return 1; 148 } 149 150 static int luaB_rawset (lua_State *L) { 151 luaL_checktype(L, 1, LUA_TTABLE); 152 luaL_checkany(L, 2); 153 luaL_checkany(L, 3); 154 lua_settop(L, 3); 155 lua_rawset(L, 1); 156 return 1; 157 } 158 159 160 static int luaB_collectgarbage (lua_State *L) { 161 static const char *const opts[] = {"stop", "restart", "collect", 162 "count", "step", "setpause", "setstepmul", 163 "setmajorinc", "isrunning", "generational", "incremental", NULL}; 164 static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT, 165 LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL, 166 LUA_GCSETMAJORINC, LUA_GCISRUNNING, LUA_GCGEN, LUA_GCINC}; 167 int o = optsnum[luaL_checkoption(L, 1, "collect", opts)]; 168 int ex = luaL_optint(L, 2, 0); 169 int res = lua_gc(L, o, ex); 170 switch (o) { 171 case LUA_GCCOUNT: { 172 int b = lua_gc(L, LUA_GCCOUNTB, 0); 173 lua_pushnumber(L, res + ((lua_Number)b/1024)); 174 lua_pushinteger(L, b); 175 return 2; 176 } 177 case LUA_GCSTEP: case LUA_GCISRUNNING: { 178 lua_pushboolean(L, res); 179 return 1; 180 } 181 default: { 182 lua_pushinteger(L, res); 183 return 1; 184 } 185 } 186 } 187 188 189 static int luaB_type (lua_State *L) { 190 luaL_checkany(L, 1); 191 lua_pushstring(L, luaL_typename(L, 1)); 192 return 1; 193 } 194 195 196 static int pairsmeta (lua_State *L, const char *method, int iszero, 197 lua_CFunction iter) { 198 if (!luaL_getmetafield(L, 1, method)) { /* no metamethod? */ 199 luaL_checktype(L, 1, LUA_TTABLE); /* argument must be a table */ 200 lua_pushcfunction(L, iter); /* will return generator, */ 201 lua_pushvalue(L, 1); /* state, */ 202 if (iszero) lua_pushinteger(L, 0); /* and initial value */ 203 else lua_pushnil(L); 204 } 205 else { 206 lua_pushvalue(L, 1); /* argument 'self' to metamethod */ 207 lua_call(L, 1, 3); /* get 3 values from metamethod */ 208 } 209 return 3; 210 } 211 212 213 static int luaB_next (lua_State *L) { 214 luaL_checktype(L, 1, LUA_TTABLE); 215 lua_settop(L, 2); /* create a 2nd argument if there isn't one */ 216 if (lua_next(L, 1)) 217 return 2; 218 else { 219 lua_pushnil(L); 220 return 1; 221 } 222 } 223 224 225 static int luaB_pairs (lua_State *L) { 226 return pairsmeta(L, "__pairs", 0, luaB_next); 227 } 228 229 230 static int ipairsaux (lua_State *L) { 231 int i = luaL_checkint(L, 2); 232 luaL_checktype(L, 1, LUA_TTABLE); 233 i++; /* next value */ 234 lua_pushinteger(L, i); 235 lua_rawgeti(L, 1, i); 236 return (lua_isnil(L, -1)) ? 1 : 2; 237 } 238 239 240 static int luaB_ipairs (lua_State *L) { 241 return pairsmeta(L, "__ipairs", 1, ipairsaux); 242 } 243 244 245 static int load_aux (lua_State *L, int status, int envidx) { 246 if (status == LUA_OK) { 247 if (envidx != 0) { /* 'env' parameter? */ 248 lua_pushvalue(L, envidx); /* environment for loaded function */ 249 if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */ 250 lua_pop(L, 1); /* remove 'env' if not used by previous call */ 251 } 252 return 1; 253 } 254 else { /* error (message is on top of the stack) */ 255 lua_pushnil(L); 256 lua_insert(L, -2); /* put before error message */ 257 return 2; /* return nil plus error message */ 258 } 259 } 260 261 262 static int luaB_loadfile (lua_State *L) { 263 const char *fname = luaL_optstring(L, 1, NULL); 264 const char *mode = luaL_optstring(L, 2, NULL); 265 int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */ 266 int status = luaL_loadfilex(L, fname, mode); 267 return load_aux(L, status, env); 268 } 269 270 271 /* 272 ** {====================================================== 273 ** Generic Read function 274 ** ======================================================= 275 */ 276 277 278 /* 279 ** reserved slot, above all arguments, to hold a copy of the returned 280 ** string to avoid it being collected while parsed. 'load' has four 281 ** optional arguments (chunk, source name, mode, and environment). 282 */ 283 #define RESERVEDSLOT 5 284 285 286 /* 287 ** Reader for generic `load' function: `lua_load' uses the 288 ** stack for internal stuff, so the reader cannot change the 289 ** stack top. Instead, it keeps its resulting string in a 290 ** reserved slot inside the stack. 291 */ 292 static const char *generic_reader (lua_State *L, void *ud, size_t *size) { 293 (void)(ud); /* not used */ 294 luaL_checkstack(L, 2, "too many nested functions"); 295 lua_pushvalue(L, 1); /* get function */ 296 lua_call(L, 0, 1); /* call it */ 297 if (lua_isnil(L, -1)) { 298 lua_pop(L, 1); /* pop result */ 299 *size = 0; 300 return NULL; 301 } 302 else if (!lua_isstring(L, -1)) 303 luaL_error(L, "reader function must return a string"); 304 lua_replace(L, RESERVEDSLOT); /* save string in reserved slot */ 305 return lua_tolstring(L, RESERVEDSLOT, size); 306 } 307 308 309 static int luaB_load (lua_State *L) { 310 int status; 311 size_t l; 312 const char *s = lua_tolstring(L, 1, &l); 313 const char *mode = luaL_optstring(L, 3, "bt"); 314 int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */ 315 if (s != NULL) { /* loading a string? */ 316 const char *chunkname = luaL_optstring(L, 2, s); 317 status = luaL_loadbufferx(L, s, l, chunkname, mode); 318 } 319 else { /* loading from a reader function */ 320 const char *chunkname = luaL_optstring(L, 2, "=(load)"); 321 luaL_checktype(L, 1, LUA_TFUNCTION); 322 lua_settop(L, RESERVEDSLOT); /* create reserved slot */ 323 status = lua_load(L, generic_reader, NULL, chunkname, mode); 324 } 325 return load_aux(L, status, env); 326 } 327 328 /* }====================================================== */ 329 330 331 static int dofilecont (lua_State *L) { 332 return lua_gettop(L) - 1; 333 } 334 335 336 static int luaB_dofile (lua_State *L) { 337 const char *fname = luaL_optstring(L, 1, NULL); 338 lua_settop(L, 1); 339 if (luaL_loadfile(L, fname) != LUA_OK) 340 return lua_error(L); 341 lua_callk(L, 0, LUA_MULTRET, 0, dofilecont); 342 return dofilecont(L); 343 } 344 345 346 static int luaB_assert (lua_State *L) { 347 if (!lua_toboolean(L, 1)) 348 return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!")); 349 return lua_gettop(L); 350 } 351 352 353 static int luaB_select (lua_State *L) { 354 int n = lua_gettop(L); 355 if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') { 356 lua_pushinteger(L, n-1); 357 return 1; 358 } 359 else { 360 int i = luaL_checkint(L, 1); 361 if (i < 0) i = n + i; 362 else if (i > n) i = n; 363 luaL_argcheck(L, 1 <= i, 1, "index out of range"); 364 return n - i; 365 } 366 } 367 368 369 static int finishpcall (lua_State *L, int status) { 370 if (!lua_checkstack(L, 1)) { /* no space for extra boolean? */ 371 lua_settop(L, 0); /* create space for return values */ 372 lua_pushboolean(L, 0); 373 lua_pushstring(L, "stack overflow"); 374 return 2; /* return false, msg */ 375 } 376 lua_pushboolean(L, status); /* first result (status) */ 377 lua_replace(L, 1); /* put first result in first slot */ 378 return lua_gettop(L); 379 } 380 381 382 static int pcallcont (lua_State *L) { 383 int status = lua_getctx(L, NULL); 384 return finishpcall(L, (status == LUA_YIELD)); 385 } 386 387 388 static int luaB_pcall (lua_State *L) { 389 int status; 390 luaL_checkany(L, 1); 391 lua_pushnil(L); 392 lua_insert(L, 1); /* create space for status result */ 393 status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, pcallcont); 394 return finishpcall(L, (status == LUA_OK)); 395 } 396 397 398 static int luaB_xpcall (lua_State *L) { 399 int status; 400 int n = lua_gettop(L); 401 luaL_argcheck(L, n >= 2, 2, "value expected"); 402 lua_pushvalue(L, 1); /* exchange function... */ 403 lua_copy(L, 2, 1); /* ...and error handler */ 404 lua_replace(L, 2); 405 status = lua_pcallk(L, n - 2, LUA_MULTRET, 1, 0, pcallcont); 406 return finishpcall(L, (status == LUA_OK)); 407 } 408 409 410 static int luaB_tostring (lua_State *L) { 411 luaL_checkany(L, 1); 412 luaL_tolstring(L, 1, NULL); 413 return 1; 414 } 415 416 417 static const luaL_Reg base_funcs[] = { 418 {"assert", luaB_assert}, 419 {"collectgarbage", luaB_collectgarbage}, 420 {"dofile", luaB_dofile}, 421 {"error", luaB_error}, 422 {"getmetatable", luaB_getmetatable}, 423 {"ipairs", luaB_ipairs}, 424 {"loadfile", luaB_loadfile}, 425 {"load", luaB_load}, 426 #if defined(LUA_COMPAT_LOADSTRING) 427 {"loadstring", luaB_load}, 428 #endif 429 {"next", luaB_next}, 430 {"pairs", luaB_pairs}, 431 {"pcall", luaB_pcall}, 432 {"print", luaB_print}, 433 {"rawequal", luaB_rawequal}, 434 {"rawlen", luaB_rawlen}, 435 {"rawget", luaB_rawget}, 436 {"rawset", luaB_rawset}, 437 {"select", luaB_select}, 438 {"setmetatable", luaB_setmetatable}, 439 {"tonumber", luaB_tonumber}, 440 {"tostring", luaB_tostring}, 441 {"type", luaB_type}, 442 {"xpcall", luaB_xpcall}, 443 {NULL, NULL} 444 }; 445 446 447 LUAMOD_API int luaopen_base (lua_State *L) { 448 /* set global _G */ 449 lua_pushglobaltable(L); 450 lua_pushglobaltable(L); 451 lua_setfield(L, -2, "_G"); 452 /* open lib into global table */ 453 luaL_setfuncs(L, base_funcs, 0); 454 lua_pushliteral(L, LUA_VERSION); 455 lua_setfield(L, -2, "_VERSION"); /* set global _VERSION */ 456 return 1; 457 } 458 459
