lua/lbaselib.c
2003-03-06 16:36:16 -03:00

669 lines
17 KiB
C

/*
** $Id: lbaselib.c,v 1.124 2003/02/27 11:52:30 roberto Exp roberto $
** Basic library
** See Copyright Notice in lua.h
*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define lbaselib_c
#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, "`tostring' must return a string to `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, 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);
luaL_checkany(L, 1);
if (!lua_isstring(L, 1) || level == 0)
lua_pushvalue(L, 1); /* propagate error message without changes */
else { /* 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) {
if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);
else {
lua_Debug ar;
int level = luaL_optint(L, 1, 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 aux_getfenv (lua_State *L) {
lua_getfenv(L, -1);
lua_pushliteral(L, "__globals");
lua_rawget(L, -2);
return !lua_isnil(L, -1);
}
static int luaB_getfenv (lua_State *L) {
getfunc(L);
if (!aux_getfenv(L)) /* __globals not defined? */
lua_pop(L, 1); /* remove it, to return real environment */
return 1;
}
static int luaB_setfenv (lua_State *L) {
luaL_checktype(L, 2, LUA_TTABLE);
getfunc(L);
if (aux_getfenv(L)) /* __globals defined? */
luaL_error(L, "cannot change a protected global table");
else
lua_pop(L, 2); /* remove __globals and real environment table */
lua_pushvalue(L, 2);
if (lua_setfenv(L, -2) == 0)
luaL_error(L, "cannot change environment of given function");
return 0;
}
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_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_rawset(L, 1);
return 1;
}
static int luaB_gcinfo (lua_State *L) {
lua_pushnumber(L, lua_getgccount(L));
lua_pushnumber(L, lua_getgcthreshold(L));
return 2;
}
static int luaB_collectgarbage (lua_State *L) {
lua_setgcthreshold(L, luaL_optint(L, 1, 0));
return 0;
}
static int luaB_type (lua_State *L) {
luaL_checkany(L, 1);
lua_pushstring(L, lua_typename(L, lua_type(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_pushliteral(L, "next");
lua_rawget(L, LUA_GLOBALSINDEX); /* return generator, */
lua_pushvalue(L, 1); /* state, */
lua_pushnil(L); /* and initial value */
return 3;
}
static int luaB_ipairs (lua_State *L) {
lua_Number i = lua_tonumber(L, 2);
luaL_checktype(L, 1, LUA_TTABLE);
if (i == 0 && lua_isnone(L, 2)) { /* `for' start? */
lua_pushliteral(L, "ipairs");
lua_rawget(L, LUA_GLOBALSINDEX); /* return generator, */
lua_pushvalue(L, 1); /* state, */
lua_pushnumber(L, 0); /* and initial value */
return 3;
}
else { /* `for' step */
i++; /* next value */
lua_pushnumber(L, i);
lua_rawgeti(L, 1, (int)i);
return (lua_isnil(L, -1)) ? 0 : 2;
}
}
static int load_aux (lua_State *L, int status) {
if (status == 0) { /* OK? */
lua_Debug ar;
lua_getstack(L, 1, &ar);
lua_getinfo(L, "f", &ar); /* get calling function */
lua_getfenv(L, -1); /* get its environment */
lua_setfenv(L, -3); /* set it as the environment of the new chunk */
lua_pop(L, 1); /* remove calling function */
return 1;
}
else {
lua_pushnil(L);
lua_insert(L, -2);
return 2;
}
}
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));
}
static int luaB_dofile (lua_State *L) {
const char *fname = luaL_optstring(L, 1, NULL);
int status = luaL_loadfile(L, fname);
if (status != 0) lua_error(L);
lua_call(L, 0, LUA_MULTRET);
return lua_gettop(L) - 1;
}
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!"));
lua_settop(L, 1);
return 1;
}
static int luaB_unpack (lua_State *L) {
int n, i;
luaL_checktype(L, 1, LUA_TTABLE);
n = luaL_getn(L, 1);
luaL_checkstack(L, n, "table too big to unpack");
for (i=1; i<=n; i++) /* push arg[1...n] */
lua_rawgeti(L, 1, i);
return n;
}
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) {
char buff[64];
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));
return 1;
case LUA_TSTRING:
lua_pushvalue(L, 1);
return 1;
case LUA_TBOOLEAN:
lua_pushstring(L, (lua_toboolean(L, 1) ? "true" : "false"));
return 1;
case LUA_TTABLE:
sprintf(buff, "table: %p", lua_topointer(L, 1));
break;
case LUA_TFUNCTION:
sprintf(buff, "function: %p", lua_topointer(L, 1));
break;
case LUA_TUSERDATA:
case LUA_TLIGHTUSERDATA:
sprintf(buff, "userdata: %p", lua_touserdata(L, 1));
break;
case LUA_TTHREAD:
sprintf(buff, "thread: %p", (void *)lua_tothread(L, 1));
break;
case LUA_TNIL:
lua_pushliteral(L, "nil");
return 1;
}
lua_pushstring(L, buff);
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;
}
/*
** {======================================================
** `require' function
** =======================================================
*/
/* name of global that holds table with loaded packages */
#define REQTAB "_LOADED"
/* name of global that holds the search path for packages */
#define LUA_PATH "LUA_PATH"
#ifndef LUA_PATH_SEP
#define LUA_PATH_SEP ';'
#endif
#ifndef LUA_PATH_DEFAULT
#define LUA_PATH_DEFAULT "?;?.lua"
#endif
static const char *getpath (lua_State *L) {
const char *path;
lua_getglobal(L, LUA_PATH); /* try global variable */
path = lua_tostring(L, -1);
lua_pop(L, 1);
if (path) return path;
path = getenv(LUA_PATH); /* else try environment variable */
if (path) return path;
return LUA_PATH_DEFAULT; /* else use default */
}
static const char *pushnextpath (lua_State *L, const char *path) {
const char *l;
if (*path == '\0') return NULL; /* no more paths */
if (*path == LUA_PATH_SEP) path++; /* skip separator */
l = strchr(path, LUA_PATH_SEP); /* find next separator */
if (l == NULL) l = path+strlen(path);
lua_pushlstring(L, path, l - path); /* directory name */
return l;
}
static void pushcomposename (lua_State *L) {
const char *path = lua_tostring(L, -1);
const char *wild = strchr(path, '?');
if (wild == NULL) return; /* no wild char; path is the file name */
lua_pushlstring(L, path, wild - path);
lua_pushvalue(L, 1); /* package name */
lua_pushstring(L, wild + 1);
lua_concat(L, 3);
}
static int luaB_require (lua_State *L) {
const char *path;
int status = LUA_ERRFILE; /* not found (yet) */
luaL_checkstring(L, 1);
lua_settop(L, 1);
lua_getglobal(L, REQTAB);
if (!lua_istable(L, 2)) return luaL_error(L, "`" REQTAB "' is not a table");
path = getpath(L);
lua_pushvalue(L, 1); /* check package's name in book-keeping table */
lua_rawget(L, 2);
if (lua_toboolean(L, -1)) /* is it there? */
return 1; /* package is already loaded; return its result */
else { /* must load it */
while (status == LUA_ERRFILE) {
lua_settop(L, 3); /* reset stack position */
if ((path = pushnextpath(L, path)) == NULL) break;
pushcomposename(L);
status = luaL_loadfile(L, lua_tostring(L, -1)); /* try to load it */
}
}
switch (status) {
case 0: {
lua_getglobal(L, "_REQUIREDNAME"); /* save previous name */
lua_insert(L, -2); /* put it below function */
lua_pushvalue(L, 1);
lua_setglobal(L, "_REQUIREDNAME"); /* set new name */
lua_call(L, 0, 1); /* run loaded module */
lua_insert(L, -2); /* put result below previous name */
lua_setglobal(L, "_REQUIREDNAME"); /* reset to previous name */
if (lua_isnil(L, -1)) { /* no/nil return? */
lua_pushboolean(L, 1);
lua_replace(L, -2); /* replace to true */
}
lua_pushvalue(L, 1);
lua_pushvalue(L, -2);
lua_rawset(L, 2); /* mark it as loaded */
return 1; /* return value */
}
case LUA_ERRFILE: { /* file not found */
return luaL_error(L, "could not load package `%s' from path `%s'",
lua_tostring(L, 1), getpath(L));
}
default: {
return luaL_error(L, "error loading package\n%s", lua_tostring(L, -1));
}
}
}
/* }====================================================== */
static const luaL_reg base_funcs[] = {
{"error", luaB_error},
{"getmetatable", luaB_getmetatable},
{"setmetatable", luaB_setmetatable},
{"getfenv", luaB_getfenv},
{"setfenv", luaB_setfenv},
{"next", luaB_next},
{"ipairs", luaB_ipairs},
{"pairs", luaB_pairs},
{"print", luaB_print},
{"tonumber", luaB_tonumber},
{"tostring", luaB_tostring},
{"type", luaB_type},
{"assert", luaB_assert},
{"unpack", luaB_unpack},
{"rawequal", luaB_rawequal},
{"rawget", luaB_rawget},
{"rawset", luaB_rawset},
{"pcall", luaB_pcall},
{"xpcall", luaB_xpcall},
{"collectgarbage", luaB_collectgarbage},
{"gcinfo", luaB_gcinfo},
{"loadfile", luaB_loadfile},
{"dofile", luaB_dofile},
{"loadstring", luaB_loadstring},
{"require", luaB_require},
{NULL, NULL}
};
/*
** {======================================================
** Coroutine library
** =======================================================
*/
static int auxresume (lua_State *L, lua_State *co, int narg) {
int status;
if (!lua_checkstack(co, narg))
luaL_error(L, "too many arguments to resume");
lua_xmove(L, co, narg);
status = lua_resume(co, narg);
if (status == 0) {
int nres = lua_gettop(co);
if (!lua_checkstack(L, nres))
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_costatus (lua_State *L) {
lua_State *co = lua_tothread(L, 1);
luaL_argcheck(L, co, 1, "coroutine expected");
if (L == co) lua_pushliteral(L, "running");
else {
lua_Debug ar;
if (lua_getstack(co, 0, &ar) == 0 && lua_gettop(co) == 0)
lua_pushliteral(L, "dead");
else
lua_pushliteral(L, "suspended");
}
return 1;
}
static const luaL_reg co_funcs[] = {
{"create", luaB_cocreate},
{"wrap", luaB_cowrap},
{"resume", luaB_coresume},
{"yield", luaB_yield},
{"status", luaB_costatus},
{NULL, NULL}
};
/* }====================================================== */
static void base_open (lua_State *L) {
lua_pushliteral(L, "_G");
lua_pushvalue(L, LUA_GLOBALSINDEX);
luaL_openlib(L, NULL, base_funcs, 0); /* open lib into global table */
lua_pushliteral(L, "_VERSION");
lua_pushliteral(L, LUA_VERSION);
lua_rawset(L, -3); /* set global _VERSION */
/* `newproxy' needs a weaktable as upvalue */
lua_pushliteral(L, "newproxy");
lua_newtable(L); /* new table `w' */
lua_pushvalue(L, -1); /* `w' will be its own metatable */
lua_setmetatable(L, -2);
lua_pushliteral(L, "__mode");
lua_pushliteral(L, "k");
lua_rawset(L, -3); /* metatable(w).__mode = "k" */
lua_pushcclosure(L, luaB_newproxy, 1);
lua_rawset(L, -3); /* set global `newproxy' */
lua_rawset(L, -1); /* set global _G */
}
LUALIB_API int lua_baselibopen (lua_State *L) {
base_open(L);
luaL_openlib(L, LUA_COLIBNAME, co_funcs, 0);
lua_newtable(L);
lua_setglobal(L, REQTAB);
return 0;
}