lbaselib.c
(5.3.6)
/*
** $Id: lbaselib.c,v 1.314.1.1 2017/04/19 17:39:34 roberto Exp $
** Basic library
** See Copyright Notice in lua.h
*/
#define lbaselib_c
#define LUA_LIB
#include "lprefix.h"
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
static int luaB_print (lua_State *L) {
int n = lua_gettop(L); /* number of arguments */
int i;
lua_getglobal(L, "tostring");
for (i=1; i<=n; i++) {
const char *s;
size_t l;
lua_pushvalue(L, -1); /* function to be called */
lua_pushvalue(L, i); /* value to print */
lua_call(L, 1, 1);
s = lua_tolstring(L, -1, &l); /* get result */
if (s == NULL)
return luaL_error(L, "'tostring' must return a string to 'print'");
if (i>1) lua_writestring("\t", 1);
lua_writestring(s, l);
lua_pop(L, 1); /* pop result */
}
lua_writeline();
return 0;
}
#define SPACECHARS " \f\n\r\t\v"
static const char *b_str2int (const char *s, int base, lua_Integer *pn) {
lua_Unsigned n = 0;
int neg = 0;
s += strspn(s, SPACECHARS); /* skip initial spaces */
if (*s == '-') { s++; neg = 1; } /* handle signal */
else if (*s == '+') s++;
if (!isalnum((unsigned char)*s)) /* no digit? */
return NULL;
do {
int digit = (isdigit((unsigned char)*s)) ? *s - '0'
: (toupper((unsigned char)*s) - 'A') + 10;
if (digit >= base) return NULL; /* invalid numeral */
n = n * base + digit;
s++;
} while (isalnum((unsigned char)*s));
s += strspn(s, SPACECHARS); /* skip trailing spaces */
*pn = (lua_Integer)((neg) ? (0u - n) : n);
return s;
}
static int luaB_tonumber (lua_State *L) {
if (lua_isnoneornil(L, 2)) { /* standard conversion? */
luaL_checkany(L, 1);
if (lua_type(L, 1) == LUA_TNUMBER) { /* already a number? */
lua_settop(L, 1); /* yes; return it */
return 1;
}
else {
size_t l;
const char *s = lua_tolstring(L, 1, &l);
if (s != NULL && lua_stringtonumber(L, s) == l + 1)
return 1; /* successful conversion to number */
/* else not a number */
}
}
else {
size_t l;
const char *s;
lua_Integer n = 0; /* to avoid warnings */
lua_Integer base = luaL_checkinteger(L, 2);
luaL_checktype(L, 1, LUA_TSTRING); /* no numbers as strings */
s = lua_tolstring(L, 1, &l);
luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
if (b_str2int(s, (int)base, &n) == s + l) {
lua_pushinteger(L, n);
return 1;
} /* else not a number */
} /* else not a number */
lua_pushnil(L); /* not a number */
return 1;
}
static int luaB_error (lua_State *L) {
int level = (int)luaL_optinteger(L, 2, 1);
lua_settop(L, 1);
if (lua_type(L, 1) == LUA_TSTRING && level > 0) {
luaL_where(L, level); /* add extra information */
lua_pushvalue(L, 1);
lua_concat(L, 2);
}
return lua_error(L);
}
static int luaB_getmetatable (lua_State *L) {
luaL_checkany(L, 1);
if (!lua_getmetatable(L, 1)) {
lua_pushnil(L);
return 1; /* no metatable */
}
luaL_getmetafield(L, 1, "__metatable");
return 1; /* returns either __metatable field (if present) or metatable */
}
static int luaB_setmetatable (lua_State *L) {
int t = lua_type(L, 2);
luaL_checktype(L, 1, LUA_TTABLE);
luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
"nil or table expected");
if (luaL_getmetafield(L, 1, "__metatable") != LUA_TNIL)
return luaL_error(L, "cannot change a protected metatable");
lua_settop(L, 2);
lua_setmetatable(L, 1);
return 1;
}
static int luaB_rawequal (lua_State *L) {
luaL_checkany(L, 1);
luaL_checkany(L, 2);
lua_pushboolean(L, lua_rawequal(L, 1, 2));
return 1;
}
static int luaB_rawlen (lua_State *L) {
int t = lua_type(L, 1);
luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
"table or string expected");
lua_pushinteger(L, lua_rawlen(L, 1));
return 1;
}
static int luaB_rawget (lua_State *L) {
luaL_checktype(L, 1, LUA_TTABLE);
luaL_checkany(L, 2);
lua_settop(L, 2);
lua_rawget(L, 1);
return 1;
}
static int luaB_rawset (lua_State *L) {
luaL_checktype(L, 1, LUA_TTABLE);
luaL_checkany(L, 2);
luaL_checkany(L, 3);
lua_settop(L, 3);
lua_rawset(L, 1);
return 1;
}
static int luaB_collectgarbage (lua_State *L) {
static const char *const opts[] = {"stop", "restart", "collect",
"count", "step", "setpause", "setstepmul",
"isrunning", NULL};
static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
LUA_GCISRUNNING};
int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
int ex = (int)luaL_optinteger(L, 2, 0);
int res = lua_gc(L, o, ex);
switch (o) {
case LUA_GCCOUNT: {
int b = lua_gc(L, LUA_GCCOUNTB, 0);
lua_pushnumber(L, (lua_Number)res + ((lua_Number)b/1024));
return 1;
}
case LUA_GCSTEP: case LUA_GCISRUNNING: {
lua_pushboolean(L, res);
return 1;
}
default: {
lua_pushinteger(L, res);
return 1;
}
}
}
static int luaB_type (lua_State *L) {
int t = lua_type(L, 1);
luaL_argcheck(L, t != LUA_TNONE, 1, "value expected");
lua_pushstring(L, lua_typename(L, t));
return 1;
}
static int pairsmeta (lua_State *L, const char *method, int iszero,
lua_CFunction iter) {
luaL_checkany(L, 1);
if (luaL_getmetafield(L, 1, method) == LUA_TNIL) { /* no metamethod? */
lua_pushcfunction(L, iter); /* will return generator, */
lua_pushvalue(L, 1); /* state, */
if (iszero) lua_pushinteger(L, 0); /* and initial value */
else lua_pushnil(L);
}
else {
lua_pushvalue(L, 1); /* argument 'self' to metamethod */
lua_call(L, 1, 3); /* get 3 values from metamethod */
}
return 3;
}
static int luaB_next (lua_State *L) {
luaL_checktype(L, 1, LUA_TTABLE);
lua_settop(L, 2); /* create a 2nd argument if there isn't one */
if (lua_next(L, 1))
return 2;
else {
lua_pushnil(L);
return 1;
}
}
static int luaB_pairs (lua_State *L) {
return pairsmeta(L, "__pairs", 0, luaB_next);
}
/*
** Traversal function for 'ipairs'
*/
static int ipairsaux (lua_State *L) {
lua_Integer i = luaL_checkinteger(L, 2) + 1;
lua_pushinteger(L, i);
return (lua_geti(L, 1, i) == LUA_TNIL) ? 1 : 2;
}
/*
** 'ipairs' function. Returns 'ipairsaux', given "table", 0.
** (The given "table" may not be a table.)
*/
static int luaB_ipairs (lua_State *L) {
#if defined(LUA_COMPAT_IPAIRS)
return pairsmeta(L, "__ipairs", 1, ipairsaux);
#else
luaL_checkany(L, 1);
lua_pushcfunction(L, ipairsaux); /* iteration function */
lua_pushvalue(L, 1); /* state */
lua_pushinteger(L, 0); /* initial value */
return 3;
#endif
}
static int load_aux (lua_State *L, int status, int envidx) {
if (status == LUA_OK) {
if (envidx != 0) { /* 'env' parameter? */
lua_pushvalue(L, envidx); /* environment for loaded function */
if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */
lua_pop(L, 1); /* remove 'env' if not used by previous call */
}
return 1;
}
else { /* error (message is on top of the stack) */
lua_pushnil(L);
lua_insert(L, -2); /* put before error message */
return 2; /* return nil plus error message */
}
}
static int luaB_loadfile (lua_State *L) {
const char *fname = luaL_optstring(L, 1, NULL);
const char *mode = luaL_optstring(L, 2, NULL);
int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */
int status = luaL_loadfilex(L, fname, mode);
return load_aux(L, status, env);
}
/*
** {======================================================
** Generic Read function
** =======================================================
*/
/*
** reserved slot, above all arguments, to hold a copy of the returned
** string to avoid it being collected while parsed. 'load' has four
** optional arguments (chunk, source name, mode, and environment).
*/
#define RESERVEDSLOT 5
/*
** Reader for generic 'load' function: 'lua_load' uses the
** stack for internal stuff, so the reader cannot change the
** stack top. Instead, it keeps its resulting string in a
** reserved slot inside the stack.
*/
static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
(void)(ud); /* not used */
luaL_checkstack(L, 2, "too many nested functions");
lua_pushvalue(L, 1); /* get function */
lua_call(L, 0, 1); /* call it */
if (lua_isnil(L, -1)) {
lua_pop(L, 1); /* pop result */
*size = 0;
return NULL;
}
else if (!lua_isstring(L, -1))
luaL_error(L, "reader function must return a string");
lua_replace(L, RESERVEDSLOT); /* save string in reserved slot */
return lua_tolstring(L, RESERVEDSLOT, size);
}
static int luaB_load (lua_State *L) {
int status;
size_t l;
const char *s = lua_tolstring(L, 1, &l);
const char *mode = luaL_optstring(L, 3, "bt");
int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */
if (s != NULL) { /* loading a string? */
const char *chunkname = luaL_optstring(L, 2, s);
status = luaL_loadbufferx(L, s, l, chunkname, mode);
}
else { /* loading from a reader function */
const char *chunkname = luaL_optstring(L, 2, "=(load)");
luaL_checktype(L, 1, LUA_TFUNCTION);
lua_settop(L, RESERVEDSLOT); /* create reserved slot */
status = lua_load(L, generic_reader, NULL, chunkname, mode);
}
return load_aux(L, status, env);
}
/* }====================================================== */
static int dofilecont (lua_State *L, int d1, lua_KContext d2) {
(void)d1; (void)d2; /* only to match 'lua_Kfunction' prototype */
return lua_gettop(L) - 1;
}
static int luaB_dofile (lua_State *L) {
const char *fname = luaL_optstring(L, 1, NULL);
lua_settop(L, 1);
if (luaL_loadfile(L, fname) != LUA_OK)
return lua_error(L);
lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
return dofilecont(L, 0, 0);
}
static int luaB_assert (lua_State *L) {
if (lua_toboolean(L, 1)) /* condition is true? */
return lua_gettop(L); /* return all arguments */
else { /* error */
luaL_checkany(L, 1); /* there must be a condition */
lua_remove(L, 1); /* remove it */
lua_pushliteral(L, "assertion failed!"); /* default message */
lua_settop(L, 1); /* leave only message (default if no other one) */
return luaB_error(L); /* call 'error' */
}
}
static int luaB_select (lua_State *L) {
int n = lua_gettop(L);
if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
lua_pushinteger(L, n-1);
return 1;
}
else {
lua_Integer i = luaL_checkinteger(L, 1);
if (i < 0) i = n + i;
else if (i > n) i = n;
luaL_argcheck(L, 1 <= i, 1, "index out of range");
return n - (int)i;
}
}
/*
** Continuation function for 'pcall' and 'xpcall'. Both functions
** already pushed a 'true' before doing the call, so in case of success
** 'finishpcall' only has to return everything in the stack minus
** 'extra' values (where 'extra' is exactly the number of items to be
** ignored).
*/
static int finishpcall (lua_State *L, int status, lua_KContext extra) {
if (status != LUA_OK && status != LUA_YIELD) { /* error? */
lua_pushboolean(L, 0); /* first result (false) */
lua_pushvalue(L, -2); /* error message */
return 2; /* return false, msg */
}
else
return lua_gettop(L) - (int)extra; /* return all results */
}
static int luaB_pcall (lua_State *L) {
int status;
luaL_checkany(L, 1);
lua_pushboolean(L, 1); /* first result if no errors */
lua_insert(L, 1); /* put it in place */
status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
return finishpcall(L, status, 0);
}
/*
** Do a protected call with error handling. After 'lua_rotate', the
** stack will have <f, err, true, f, [args...]>; so, the function passes
** 2 to 'finishpcall' to skip the 2 first values when returning results.
*/
static int luaB_xpcall (lua_State *L) {
int status;
int n = lua_gettop(L);
luaL_checktype(L, 2, LUA_TFUNCTION); /* check error function */
lua_pushboolean(L, 1); /* first result */
lua_pushvalue(L, 1); /* function */
lua_rotate(L, 3, 2); /* move them below function's arguments */
status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
return finishpcall(L, status, 2);
}
static int luaB_tostring (lua_State *L) {
luaL_checkany(L, 1);
luaL_tolstring(L, 1, NULL);
return 1;
}
static const luaL_Reg base_funcs[] = {
{"assert", luaB_assert},
{"collectgarbage", luaB_collectgarbage},
{"dofile", luaB_dofile},
{"error", luaB_error},
{"getmetatable", luaB_getmetatable},
{"ipairs", luaB_ipairs},
{"loadfile", luaB_loadfile},
{"load", luaB_load},
#if defined(LUA_COMPAT_LOADSTRING)
{"loadstring", luaB_load},
#endif
{"next", luaB_next},
{"pairs", luaB_pairs},
{"pcall", luaB_pcall},
{"print", luaB_print},
{"rawequal", luaB_rawequal},
{"rawlen", luaB_rawlen},
{"rawget", luaB_rawget},
{"rawset", luaB_rawset},
{"select", luaB_select},
{"setmetatable", luaB_setmetatable},
{"tonumber", luaB_tonumber},
{"tostring", luaB_tostring},
{"type", luaB_type},
{"xpcall", luaB_xpcall},
/* placeholders */
{"_G", NULL},
{"_VERSION", NULL},
{NULL, NULL}
};
LUAMOD_API int luaopen_base (lua_State *L) {
/* open lib into global table */
lua_pushglobaltable(L);
luaL_setfuncs(L, base_funcs, 0);
/* set global _G */
lua_pushvalue(L, -1);
lua_setfield(L, -2, "_G");
/* set global _VERSION */
lua_pushliteral(L, LUA_VERSION);
lua_setfield(L, -2, "_VERSION");
return 1;
}