Lua lbaselib.c (5.0.3)

/*
** $Id: lbaselib.c,v 1.130c 2003年04月03日 13:35:34 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
#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円') { /* 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);
 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, "__fenv");
 lua_rawget(L, -2);
 return !lua_isnil(L, -1);
}
static int luaB_getfenv (lua_State *L) {
 getfunc(L);
 if (!aux_getfenv(L)) /* __fenv 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)) /* __fenv defined? */
 luaL_error(L, "`setfenv' cannot change a protected environment");
 else
 lua_pop(L, 2); /* remove __fenv and real environment table */
 lua_pushvalue(L, 2);
 if (lua_isnumber(L, 1) && lua_tonumber(L, 1) == 0)
 lua_replace(L, LUA_GLOBALSINDEX);
 else if (lua_setfenv(L, -2) == 0)
 luaL_error(L, "`setfenv' 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_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_pushnumber(L, (lua_Number)lua_getgccount(L));
 lua_pushnumber(L, (lua_Number)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? */
 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));
}
static int luaB_dofile (lua_State *L) {
 const char *fname = luaL_optstring(L, 1, NULL);
 int n = lua_gettop(L);
 int status = luaL_loadfile(L, fname);
 if (status != 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!"));
 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[128];
 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_MARK
#define LUA_PATH_MARK '?'
#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円') 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;
 int n = 1;
 while ((wild = strchr(path, LUA_PATH_MARK)) != NULL) {
 /* is there stack space for prefix, name, and eventual last sufix? */
 luaL_checkstack(L, 3, "too many marks in a path component");
 lua_pushlstring(L, path, wild - path); /* push prefix */
 lua_pushvalue(L, 1); /* push package name (in place of MARK) */
 path = wild + 1; /* continue after MARK */
 n += 2;
 }
 lua_pushstring(L, path); /* push last sufix (`n' already includes this) */
 lua_concat(L, n);
}
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 `%s' (%s)",
 lua_tostring(L, 1), 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 luaopen_base (lua_State *L) {
 base_open(L);
 luaL_openlib(L, LUA_COLIBNAME, co_funcs, 0);
 lua_newtable(L);
 lua_setglobal(L, REQTAB);
 return 0;
}

Last update: Sat Mar 5 09:25:24 2016