2 ** $Id: lbaselib.c,v 1.312 2015/10/29 15:21:04 roberto Exp $
4 ** See Copyright Notice in lua.h
24 static int luaB_print (lua_State *L) {
25 int n = lua_gettop(L); /* number of arguments */
27 lua_getglobal(L, "tostring");
28 for (i=1; i<=n; i++) {
31 lua_pushvalue(L, -1); /* function to be called */
32 lua_pushvalue(L, i); /* value to print */
34 s = lua_tolstring(L, -1, &l); /* get result */
36 return luaL_error(L, "'tostring' must return a string to 'print'");
37 if (i>1) lua_writestring("\t", 1);
38 lua_writestring(s, l);
39 lua_pop(L, 1); /* pop result */
46 #define SPACECHARS " \f\n\r\t\v"
48 static const char *b_str2int (const char *s, int base, lua_Integer *pn) {
51 s += strspn(s, SPACECHARS); /* skip initial spaces */
52 if (*s == '-') { s++; neg = 1; } /* handle signal */
53 else if (*s == '+') s++;
54 if (!isalnum((unsigned char)*s)) /* no digit? */
57 int digit = (isdigit((unsigned char)*s)) ? *s - '0'
58 : (toupper((unsigned char)*s) - 'A') + 10;
59 if (digit >= base) return NULL; /* invalid numeral */
62 } while (isalnum((unsigned char)*s));
63 s += strspn(s, SPACECHARS); /* skip trailing spaces */
64 *pn = (lua_Integer)((neg) ? (0u - n) : n);
69 static int luaB_tonumber (lua_State *L) {
70 if (lua_isnoneornil(L, 2)) { /* standard conversion? */
72 if (lua_type(L, 1) == LUA_TNUMBER) { /* already a number? */
73 lua_settop(L, 1); /* yes; return it */
78 const char *s = lua_tolstring(L, 1, &l);
79 if (s != NULL && lua_stringtonumber(L, s) == l + 1)
80 return 1; /* successful conversion to number */
81 /* else not a number */
87 lua_Integer n = 0; /* to avoid warnings */
88 lua_Integer base = luaL_checkinteger(L, 2);
89 luaL_checktype(L, 1, LUA_TSTRING); /* no numbers as strings */
90 s = lua_tolstring(L, 1, &l);
91 luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
92 if (b_str2int(s, (int)base, &n) == s + l) {
93 lua_pushinteger(L, n);
95 } /* else not a number */
96 } /* else not a number */
97 lua_pushnil(L); /* not a number */
102 static int luaB_error (lua_State *L) {
103 int level = (int)luaL_optinteger(L, 2, 1);
105 if (lua_isstring(L, 1) && level > 0) { /* add extra information? */
106 luaL_where(L, level);
114 static int luaB_getmetatable (lua_State *L) {
116 if (!lua_getmetatable(L, 1)) {
118 return 1; /* no metatable */
120 luaL_getmetafield(L, 1, "__metatable");
121 return 1; /* returns either __metatable field (if present) or metatable */
125 static int luaB_setmetatable (lua_State *L) {
126 int t = lua_type(L, 2);
127 luaL_checktype(L, 1, LUA_TTABLE);
128 luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
129 "nil or table expected");
130 if (luaL_getmetafield(L, 1, "__metatable") != LUA_TNIL)
131 return luaL_error(L, "cannot change a protected metatable");
133 lua_setmetatable(L, 1);
138 static int luaB_rawequal (lua_State *L) {
141 lua_pushboolean(L, lua_rawequal(L, 1, 2));
146 static int luaB_rawlen (lua_State *L) {
147 int t = lua_type(L, 1);
148 luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
149 "table or string expected");
150 lua_pushinteger(L, lua_rawlen(L, 1));
155 static int luaB_rawget (lua_State *L) {
156 luaL_checktype(L, 1, LUA_TTABLE);
163 static int luaB_rawset (lua_State *L) {
164 luaL_checktype(L, 1, LUA_TTABLE);
173 static int luaB_collectgarbage (lua_State *L) {
174 static const char *const opts[] = {"stop", "restart", "collect",
175 "count", "step", "setpause", "setstepmul",
177 static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
178 LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
180 int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
181 int ex = (int)luaL_optinteger(L, 2, 0);
182 int res = lua_gc(L, o, ex);
185 int b = lua_gc(L, LUA_GCCOUNTB, 0);
186 lua_pushnumber(L, (lua_Number)res + ((lua_Number)b/1024));
189 case LUA_GCSTEP: case LUA_GCISRUNNING: {
190 lua_pushboolean(L, res);
194 lua_pushinteger(L, res);
201 static int luaB_type (lua_State *L) {
202 int t = lua_type(L, 1);
203 luaL_argcheck(L, t != LUA_TNONE, 1, "value expected");
204 lua_pushstring(L, lua_typename(L, t));
209 static int pairsmeta (lua_State *L, const char *method, int iszero,
210 lua_CFunction iter) {
211 if (luaL_getmetafield(L, 1, method) == LUA_TNIL) { /* no metamethod? */
212 luaL_checktype(L, 1, LUA_TTABLE); /* argument must be a table */
213 lua_pushcfunction(L, iter); /* will return generator, */
214 lua_pushvalue(L, 1); /* state, */
215 if (iszero) lua_pushinteger(L, 0); /* and initial value */
219 lua_pushvalue(L, 1); /* argument 'self' to metamethod */
220 lua_call(L, 1, 3); /* get 3 values from metamethod */
226 static int luaB_next (lua_State *L) {
227 luaL_checktype(L, 1, LUA_TTABLE);
228 lua_settop(L, 2); /* create a 2nd argument if there isn't one */
238 static int luaB_pairs (lua_State *L) {
239 return pairsmeta(L, "__pairs", 0, luaB_next);
244 ** Traversal function for 'ipairs'
246 static int ipairsaux (lua_State *L) {
247 lua_Integer i = luaL_checkinteger(L, 2) + 1;
248 lua_pushinteger(L, i);
249 return (lua_geti(L, 1, i) == LUA_TNIL) ? 1 : 2;
254 ** This function will use either 'ipairsaux' or 'ipairsaux_raw' to
255 ** traverse a table, depending on whether the table has metamethods
256 ** that can affect the traversal.
258 static int luaB_ipairs (lua_State *L) {
259 #if defined(LUA_COMPAT_IPAIRS)
260 return pairsmeta(L, "__ipairs", 1, ipairsaux);
263 lua_pushcfunction(L, ipairsaux); /* iteration function */
264 lua_pushvalue(L, 1); /* state */
265 lua_pushinteger(L, 0); /* initial value */
271 static int load_aux (lua_State *L, int status, int envidx) {
272 if (status == LUA_OK) {
273 if (envidx != 0) { /* 'env' parameter? */
274 lua_pushvalue(L, envidx); /* environment for loaded function */
275 if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */
276 lua_pop(L, 1); /* remove 'env' if not used by previous call */
280 else { /* error (message is on top of the stack) */
282 lua_insert(L, -2); /* put before error message */
283 return 2; /* return nil plus error message */
288 static int luaB_loadfile (lua_State *L) {
289 const char *fname = luaL_optstring(L, 1, NULL);
290 const char *mode = luaL_optstring(L, 2, NULL);
291 int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */
292 int status = luaL_loadfilex(L, fname, mode);
293 return load_aux(L, status, env);
298 ** {======================================================
299 ** Generic Read function
300 ** =======================================================
305 ** reserved slot, above all arguments, to hold a copy of the returned
306 ** string to avoid it being collected while parsed. 'load' has four
307 ** optional arguments (chunk, source name, mode, and environment).
309 #define RESERVEDSLOT 5
313 ** Reader for generic 'load' function: 'lua_load' uses the
314 ** stack for internal stuff, so the reader cannot change the
315 ** stack top. Instead, it keeps its resulting string in a
316 ** reserved slot inside the stack.
318 static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
319 (void)(ud); /* not used */
320 luaL_checkstack(L, 2, "too many nested functions");
321 lua_pushvalue(L, 1); /* get function */
322 lua_call(L, 0, 1); /* call it */
323 if (lua_isnil(L, -1)) {
324 lua_pop(L, 1); /* pop result */
328 else if (!lua_isstring(L, -1))
329 luaL_error(L, "reader function must return a string");
330 lua_replace(L, RESERVEDSLOT); /* save string in reserved slot */
331 return lua_tolstring(L, RESERVEDSLOT, size);
335 static int luaB_load (lua_State *L) {
338 const char *s = lua_tolstring(L, 1, &l);
339 const char *mode = luaL_optstring(L, 3, "bt");
340 int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */
341 if (s != NULL) { /* loading a string? */
342 const char *chunkname = luaL_optstring(L, 2, s);
343 status = luaL_loadbufferx(L, s, l, chunkname, mode);
345 else { /* loading from a reader function */
346 const char *chunkname = luaL_optstring(L, 2, "=(load)");
347 luaL_checktype(L, 1, LUA_TFUNCTION);
348 lua_settop(L, RESERVEDSLOT); /* create reserved slot */
349 status = lua_load(L, generic_reader, NULL, chunkname, mode);
351 return load_aux(L, status, env);
354 /* }====================================================== */
357 static int dofilecont (lua_State *L, int d1, lua_KContext d2) {
358 (void)d1; (void)d2; /* only to match 'lua_Kfunction' prototype */
359 return lua_gettop(L) - 1;
363 static int luaB_dofile (lua_State *L) {
364 const char *fname = luaL_optstring(L, 1, NULL);
366 if (luaL_loadfile(L, fname) != LUA_OK)
368 lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
369 return dofilecont(L, 0, 0);
373 static int luaB_assert (lua_State *L) {
374 if (lua_toboolean(L, 1)) /* condition is true? */
375 return lua_gettop(L); /* return all arguments */
377 luaL_checkany(L, 1); /* there must be a condition */
378 lua_remove(L, 1); /* remove it */
379 lua_pushliteral(L, "assertion failed!"); /* default message */
380 lua_settop(L, 1); /* leave only message (default if no other one) */
381 return luaB_error(L); /* call 'error' */
386 static int luaB_select (lua_State *L) {
387 int n = lua_gettop(L);
388 if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
389 lua_pushinteger(L, n-1);
393 lua_Integer i = luaL_checkinteger(L, 1);
394 if (i < 0) i = n + i;
395 else if (i > n) i = n;
396 luaL_argcheck(L, 1 <= i, 1, "index out of range");
403 ** Continuation function for 'pcall' and 'xpcall'. Both functions
404 ** already pushed a 'true' before doing the call, so in case of success
405 ** 'finishpcall' only has to return everything in the stack minus
406 ** 'extra' values (where 'extra' is exactly the number of items to be
409 static int finishpcall (lua_State *L, int status, lua_KContext extra) {
410 if (status != LUA_OK && status != LUA_YIELD) { /* error? */
411 lua_pushboolean(L, 0); /* first result (false) */
412 lua_pushvalue(L, -2); /* error message */
413 return 2; /* return false, msg */
416 return lua_gettop(L) - (int)extra; /* return all results */
420 static int luaB_pcall (lua_State *L) {
423 lua_pushboolean(L, 1); /* first result if no errors */
424 lua_insert(L, 1); /* put it in place */
425 status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
426 return finishpcall(L, status, 0);
431 ** Do a protected call with error handling. After 'lua_rotate', the
432 ** stack will have <f, err, true, f, [args...]>; so, the function passes
433 ** 2 to 'finishpcall' to skip the 2 first values when returning results.
435 static int luaB_xpcall (lua_State *L) {
437 int n = lua_gettop(L);
438 luaL_checktype(L, 2, LUA_TFUNCTION); /* check error function */
439 lua_pushboolean(L, 1); /* first result */
440 lua_pushvalue(L, 1); /* function */
441 lua_rotate(L, 3, 2); /* move them below function's arguments */
442 status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
443 return finishpcall(L, status, 2);
447 static int luaB_tostring (lua_State *L) {
449 luaL_tolstring(L, 1, NULL);
454 static const luaL_Reg base_funcs[] = {
455 {"assert", luaB_assert},
456 {"collectgarbage", luaB_collectgarbage},
457 {"dofile", luaB_dofile},
458 {"error", luaB_error},
459 {"getmetatable", luaB_getmetatable},
460 {"ipairs", luaB_ipairs},
461 {"loadfile", luaB_loadfile},
463 #if defined(LUA_COMPAT_LOADSTRING)
464 {"loadstring", luaB_load},
467 {"pairs", luaB_pairs},
468 {"pcall", luaB_pcall},
469 {"print", luaB_print},
470 {"rawequal", luaB_rawequal},
471 {"rawlen", luaB_rawlen},
472 {"rawget", luaB_rawget},
473 {"rawset", luaB_rawset},
474 {"select", luaB_select},
475 {"setmetatable", luaB_setmetatable},
476 {"tonumber", luaB_tonumber},
477 {"tostring", luaB_tostring},
479 {"xpcall", luaB_xpcall},
487 LUAMOD_API int luaopen_base (lua_State *L) {
488 /* open lib into global table */
489 lua_pushglobaltable(L);
490 luaL_setfuncs(L, base_funcs, 0);
492 lua_pushvalue(L, -1);
493 lua_setfield(L, -2, "_G");
494 /* set global _VERSION */
495 lua_pushliteral(L, LUA_VERSION);
496 lua_setfield(L, -2, "_VERSION");