lbaselib.c
(5.1.5)
/*
** $Id: lbaselib.c,v 1.191.1.6 2008/02/14 16:46:22 roberto Exp $
** Basic library
** See Copyright Notice in lua.h
*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define lbaselib_c
#define LUA_LIB
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
/*
** If your system does not support `stdout', you can just remove this function.
** If you need, you can define your own `print' function, following this
** model but changing `fputs' to put the strings at a proper place
** (a console window or a log file, for instance).
*/
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;
lua_pushvalue(L, -1); /* function to be called */
lua_pushvalue(L, i); /* value to print */
lua_call(L, 1, 1);
s = lua_tostring(L, -1); /* get result */
if (s == NULL)
return luaL_error(L, LUA_QL("tostring") " must return a string to "
LUA_QL("print"));
if (i>1) fputs("\t", stdout);
fputs(s, stdout);
lua_pop(L, 1); /* pop result */
}
fputs("\n", stdout);
return 0;
}
static int luaB_tonumber (lua_State *L) {
int base = luaL_optint(L, 2, 10);
if (base == 10) { /* standard conversion */
luaL_checkany(L, 1);
if (lua_isnumber(L, 1)) {
lua_pushnumber(L, lua_tonumber(L, 1));
return 1;
}
}
else {
const char *s1 = luaL_checkstring(L, 1);
char *s2;
unsigned long n;
luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
n = strtoul(s1, &s2, base);
if (s1 != s2) { /* at least one valid digit? */
while (isspace((unsigned char)(*s2))) s2++; /* skip trailing spaces */
if (*s2 == '\0') { /* no invalid trailing characters? */
lua_pushnumber(L, (lua_Number)n);
return 1;
}
}
}
lua_pushnil(L); /* else not a number */
return 1;
}
static int luaB_error (lua_State *L) {
int level = luaL_optint(L, 2, 1);
lua_settop(L, 1);
if (lua_isstring(L, 1) && level > 0) { /* add extra information? */
luaL_where(L, level);
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"))
luaL_error(L, "cannot change a protected metatable");
lua_settop(L, 2);
lua_setmetatable(L, 1);
return 1;
}
static void getfunc (lua_State *L, int opt) {
if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);
else {
lua_Debug ar;
int level = opt ? luaL_optint(L, 1, 1) : luaL_checkint(L, 1);
luaL_argcheck(L, level >= 0, 1, "level must be non-negative");
if (lua_getstack(L, level, &ar) == 0)
luaL_argerror(L, 1, "invalid level");
lua_getinfo(L, "f", &ar);
if (lua_isnil(L, -1))
luaL_error(L, "no function environment for tail call at level %d",
level);
}
}
static int luaB_getfenv (lua_State *L) {
getfunc(L, 1);
if (lua_iscfunction(L, -1)) /* is a C function? */
lua_pushvalue(L, LUA_GLOBALSINDEX); /* return the thread's global env. */
else
lua_getfenv(L, -1);
return 1;
}
static int luaB_setfenv (lua_State *L) {
luaL_checktype(L, 2, LUA_TTABLE);
getfunc(L, 0);
lua_pushvalue(L, 2);
if (lua_isnumber(L, 1) && lua_tonumber(L, 1) == 0) {
/* change environment of current thread */
lua_pushthread(L);
lua_insert(L, -2);
lua_setfenv(L, -2);
return 0;
}
else if (lua_iscfunction(L, -2) || lua_setfenv(L, -2) == 0)
luaL_error(L,
LUA_QL("setfenv") " cannot change environment of given object");
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_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_gcinfo (lua_State *L) {
lua_pushinteger(L, lua_getgccount(L));
return 1;
}
static int luaB_collectgarbage (lua_State *L) {
static const char *const opts[] = {"stop", "restart", "collect",
"count", "step", "setpause", "setstepmul", NULL};
static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL};
int o = luaL_checkoption(L, 1, "collect", opts);
int ex = luaL_optint(L, 2, 0);
int res = lua_gc(L, optsnum[o], ex);
switch (optsnum[o]) {
case LUA_GCCOUNT: {
int b = lua_gc(L, LUA_GCCOUNTB, 0);
lua_pushnumber(L, res + ((lua_Number)b/1024));
return 1;
}
case LUA_GCSTEP: {
lua_pushboolean(L, res);
return 1;
}
default: {
lua_pushnumber(L, res);
return 1;
}
}
}
static int luaB_type (lua_State *L) {
luaL_checkany(L, 1);
lua_pushstring(L, luaL_typename(L, 1));
return 1;
}
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) {
luaL_checktype(L, 1, LUA_TTABLE);
lua_pushvalue(L, lua_upvalueindex(1)); /* return generator, */
lua_pushvalue(L, 1); /* state, */
lua_pushnil(L); /* and initial value */
return 3;
}
static int ipairsaux (lua_State *L) {
int i = luaL_checkint(L, 2);
luaL_checktype(L, 1, LUA_TTABLE);
i++; /* next value */
lua_pushinteger(L, i);
lua_rawgeti(L, 1, i);
return (lua_isnil(L, -1)) ? 0 : 2;
}
static int luaB_ipairs (lua_State *L) {
luaL_checktype(L, 1, LUA_TTABLE);
lua_pushvalue(L, lua_upvalueindex(1)); /* return generator, */
lua_pushvalue(L, 1); /* state, */
lua_pushinteger(L, 0); /* and initial value */
return 3;
}
static int load_aux (lua_State *L, int status) {
if (status == 0) /* OK? */
return 1;
else {
lua_pushnil(L);
lua_insert(L, -2); /* put before error message */
return 2; /* return nil plus error message */
}
}
static int luaB_loadstring (lua_State *L) {
size_t l;
const char *s = luaL_checklstring(L, 1, &l);
const char *chunkname = luaL_optstring(L, 2, s);
return load_aux(L, luaL_loadbuffer(L, s, l, chunkname));
}
static int luaB_loadfile (lua_State *L) {
const char *fname = luaL_optstring(L, 1, NULL);
return load_aux(L, luaL_loadfile(L, fname));
}
/*
** 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; /* to avoid warnings */
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)) {
*size = 0;
return NULL;
}
else if (lua_isstring(L, -1)) {
lua_replace(L, 3); /* save string in a reserved stack slot */
return lua_tolstring(L, 3, size);
}
else luaL_error(L, "reader function must return a string");
return NULL; /* to avoid warnings */
}
static int luaB_load (lua_State *L) {
int status;
const char *cname = luaL_optstring(L, 2, "=(load)");
luaL_checktype(L, 1, LUA_TFUNCTION);
lua_settop(L, 3); /* function, eventual name, plus one reserved slot */
status = lua_load(L, generic_reader, NULL, cname);
return load_aux(L, status);
}
static int luaB_dofile (lua_State *L) {
const char *fname = luaL_optstring(L, 1, NULL);
int n = lua_gettop(L);
if (luaL_loadfile(L, fname) != 0) lua_error(L);
lua_call(L, 0, LUA_MULTRET);
return lua_gettop(L) - n;
}
static int luaB_assert (lua_State *L) {
luaL_checkany(L, 1);
if (!lua_toboolean(L, 1))
return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!"));
return lua_gettop(L);
}
static int luaB_unpack (lua_State *L) {
int i, e, n;
luaL_checktype(L, 1, LUA_TTABLE);
i = luaL_optint(L, 2, 1);
e = luaL_opt(L, luaL_checkint, 3, luaL_getn(L, 1));
if (i > e) return 0; /* empty range */
n = e - i + 1; /* number of elements */
if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arith. overflow */
return luaL_error(L, "too many results to unpack");
lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */
while (i++ < e) /* push arg[i + 1...e] */
lua_rawgeti(L, 1, i);
return n;
}
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 {
int i = luaL_checkint(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 - i;
}
}
static int luaB_pcall (lua_State *L) {
int status;
luaL_checkany(L, 1);
status = lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0);
lua_pushboolean(L, (status == 0));
lua_insert(L, 1);
return lua_gettop(L); /* return status + all results */
}
static int luaB_xpcall (lua_State *L) {
int status;
luaL_checkany(L, 2);
lua_settop(L, 2);
lua_insert(L, 1); /* put error function under function to be called */
status = lua_pcall(L, 0, LUA_MULTRET, 1);
lua_pushboolean(L, (status == 0));
lua_replace(L, 1);
return lua_gettop(L); /* return status + all results */
}
static int luaB_tostring (lua_State *L) {
luaL_checkany(L, 1);
if (luaL_callmeta(L, 1, "__tostring")) /* is there a metafield? */
return 1; /* use its value */
switch (lua_type(L, 1)) {
case LUA_TNUMBER:
lua_pushstring(L, lua_tostring(L, 1));
break;
case LUA_TSTRING:
lua_pushvalue(L, 1);
break;
case LUA_TBOOLEAN:
lua_pushstring(L, (lua_toboolean(L, 1) ? "true" : "false"));
break;
case LUA_TNIL:
lua_pushliteral(L, "nil");
break;
default:
lua_pushfstring(L, "%s: %p", luaL_typename(L, 1), lua_topointer(L, 1));
break;
}
return 1;
}
static int luaB_newproxy (lua_State *L) {
lua_settop(L, 1);
lua_newuserdata(L, 0); /* create proxy */
if (lua_toboolean(L, 1) == 0)
return 1; /* no metatable */
else if (lua_isboolean(L, 1)) {
lua_newtable(L); /* create a new metatable `m' ... */
lua_pushvalue(L, -1); /* ... and mark `m' as a valid metatable */
lua_pushboolean(L, 1);
lua_rawset(L, lua_upvalueindex(1)); /* weaktable[m] = true */
}
else {
int validproxy = 0; /* to check if weaktable[metatable(u)] == true */
if (lua_getmetatable(L, 1)) {
lua_rawget(L, lua_upvalueindex(1));
validproxy = lua_toboolean(L, -1);
lua_pop(L, 1); /* remove value */
}
luaL_argcheck(L, validproxy, 1, "boolean or proxy expected");
lua_getmetatable(L, 1); /* metatable is valid; get it */
}
lua_setmetatable(L, 2);
return 1;
}
static const luaL_Reg base_funcs[] = {
{"assert", luaB_assert},
{"collectgarbage", luaB_collectgarbage},
{"dofile", luaB_dofile},
{"error", luaB_error},
{"gcinfo", luaB_gcinfo},
{"getfenv", luaB_getfenv},
{"getmetatable", luaB_getmetatable},
{"loadfile", luaB_loadfile},
{"load", luaB_load},
{"loadstring", luaB_loadstring},
{"next", luaB_next},
{"pcall", luaB_pcall},
{"print", luaB_print},
{"rawequal", luaB_rawequal},
{"rawget", luaB_rawget},
{"rawset", luaB_rawset},
{"select", luaB_select},
{"setfenv", luaB_setfenv},
{"setmetatable", luaB_setmetatable},
{"tonumber", luaB_tonumber},
{"tostring", luaB_tostring},
{"type", luaB_type},
{"unpack", luaB_unpack},
{"xpcall", luaB_xpcall},
{NULL, NULL}
};
/*
** {======================================================
** Coroutine library
** =======================================================
*/
#define CO_RUN 0 /* running */
#define CO_SUS 1 /* suspended */
#define CO_NOR 2 /* 'normal' (it resumed another coroutine) */
#define CO_DEAD 3
static const char *const statnames[] =
{"running", "suspended", "normal", "dead"};
static int costatus (lua_State *L, lua_State *co) {
if (L == co) return CO_RUN;
switch (lua_status(co)) {
case LUA_YIELD:
return CO_SUS;
case 0: {
lua_Debug ar;
if (lua_getstack(co, 0, &ar) > 0) /* does it have frames? */
return CO_NOR; /* it is running */
else if (lua_gettop(co) == 0)
return CO_DEAD;
else
return CO_SUS; /* initial state */
}
default: /* some error occured */
return CO_DEAD;
}
}
static int luaB_costatus (lua_State *L) {
lua_State *co = lua_tothread(L, 1);
luaL_argcheck(L, co, 1, "coroutine expected");
lua_pushstring(L, statnames[costatus(L, co)]);
return 1;
}
static int auxresume (lua_State *L, lua_State *co, int narg) {
int status = costatus(L, co);
if (!lua_checkstack(co, narg))
luaL_error(L, "too many arguments to resume");
if (status != CO_SUS) {
lua_pushfstring(L, "cannot resume %s coroutine", statnames[status]);
return -1; /* error flag */
}
lua_xmove(L, co, narg);
lua_setlevel(L, co);
status = lua_resume(co, narg);
if (status == 0 || status == LUA_YIELD) {
int nres = lua_gettop(co);
if (!lua_checkstack(L, nres + 1))
luaL_error(L, "too many results to resume");
lua_xmove(co, L, nres); /* move yielded values */
return nres;
}
else {
lua_xmove(co, L, 1); /* move error message */
return -1; /* error flag */
}
}
static int luaB_coresume (lua_State *L) {
lua_State *co = lua_tothread(L, 1);
int r;
luaL_argcheck(L, co, 1, "coroutine expected");
r = auxresume(L, co, lua_gettop(L) - 1);
if (r < 0) {
lua_pushboolean(L, 0);
lua_insert(L, -2);
return 2; /* return false + error message */
}
else {
lua_pushboolean(L, 1);
lua_insert(L, -(r + 1));
return r + 1; /* return true + `resume' returns */
}
}
static int luaB_auxwrap (lua_State *L) {
lua_State *co = lua_tothread(L, lua_upvalueindex(1));
int r = auxresume(L, co, lua_gettop(L));
if (r < 0) {
if (lua_isstring(L, -1)) { /* error object is a string? */
luaL_where(L, 1); /* add extra info */
lua_insert(L, -2);
lua_concat(L, 2);
}
lua_error(L); /* propagate error */
}
return r;
}
static int luaB_cocreate (lua_State *L) {
lua_State *NL = lua_newthread(L);
luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,
"Lua function expected");
lua_pushvalue(L, 1); /* move function to top */
lua_xmove(L, NL, 1); /* move function from L to NL */
return 1;
}
static int luaB_cowrap (lua_State *L) {
luaB_cocreate(L);
lua_pushcclosure(L, luaB_auxwrap, 1);
return 1;
}
static int luaB_yield (lua_State *L) {
return lua_yield(L, lua_gettop(L));
}
static int luaB_corunning (lua_State *L) {
if (lua_pushthread(L))
lua_pushnil(L); /* main thread is not a coroutine */
return 1;
}
static const luaL_Reg co_funcs[] = {
{"create", luaB_cocreate},
{"resume", luaB_coresume},
{"running", luaB_corunning},
{"status", luaB_costatus},
{"wrap", luaB_cowrap},
{"yield", luaB_yield},
{NULL, NULL}
};
/* }====================================================== */
static void auxopen (lua_State *L, const char *name,
lua_CFunction f, lua_CFunction u) {
lua_pushcfunction(L, u);
lua_pushcclosure(L, f, 1);
lua_setfield(L, -2, name);
}
static void base_open (lua_State *L) {
/* set global _G */
lua_pushvalue(L, LUA_GLOBALSINDEX);
lua_setglobal(L, "_G");
/* open lib into global table */
luaL_register(L, "_G", base_funcs);
lua_pushliteral(L, LUA_VERSION);
lua_setglobal(L, "_VERSION"); /* set global _VERSION */
/* `ipairs' and `pairs' need auxiliary functions as upvalues */
auxopen(L, "ipairs", luaB_ipairs, ipairsaux);
auxopen(L, "pairs", luaB_pairs, luaB_next);
/* `newproxy' needs a weaktable as upvalue */
lua_createtable(L, 0, 1); /* new table `w' */
lua_pushvalue(L, -1); /* `w' will be its own metatable */
lua_setmetatable(L, -2);
lua_pushliteral(L, "kv");
lua_setfield(L, -2, "__mode"); /* metatable(w).__mode = "kv" */
lua_pushcclosure(L, luaB_newproxy, 1);
lua_setglobal(L, "newproxy"); /* set global `newproxy' */
}
LUALIB_API int luaopen_base (lua_State *L) {
base_open(L);
luaL_register(L, LUA_COLIBNAME, co_funcs);
return 2;
}