lua/lbaselib.c

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/*
** $Id: $
** Basic library
** See Copyright Notice in lua.h
*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
/*
** If your system does not support `stderr', redefine this function, or
** redefine _ERRORMESSAGE so that it won't need _ALERT.
*/
static int luaB__ALERT (lua_State *L) {
fputs(luaL_check_string(L, 1), stderr);
return 0;
}
/*
** Basic implementation of _ERRORMESSAGE.
** The library `liolib' redefines _ERRORMESSAGE for better error information.
*/
static int luaB__ERRORMESSAGE (lua_State *L) {
lua_settop(L, 1);
lua_getglobals(L);
lua_pushstring(L, LUA_ALERT);
lua_rawget(L, -2);
if (lua_isfunction(L, -1)) { /* avoid error loop if _ALERT is not defined */
luaL_checktype(L, 1, "string");
lua_pushvalue(L, -1); /* function to be called */
lua_pushstring(L, "error: ");
lua_pushvalue(L, 1);
lua_pushstring(L, "\n");
lua_concat(L, 3);
lua_call(L, 1, 0);
}
return 0;
}
/*
** 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 */
if (lua_call(L, 1, 1) != 0)
lua_error(L, NULL);
s = lua_tostring(L, -1); /* get result */
if (s == NULL)
lua_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_opt_int(L, 2, 10);
if (base == 10) { /* standard conversion */
luaL_checktype(L, 1, "any");
if (lua_isnumber(L, 1)) {
lua_pushnumber(L, lua_tonumber(L, 1));
return 1;
}
}
else {
const char *s1 = luaL_check_string(L, 1);
char *s2;
unsigned long n;
luaL_arg_check(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) {
lua_error(L, luaL_opt_string(L, 1, NULL));
return 0; /* to avoid warnings */
}
static int luaB_setglobal (lua_State *L) {
luaL_checktype(L, 2, "any");
lua_setglobal(L, luaL_check_string(L, 1));
return 0;
}
static int luaB_getglobal (lua_State *L) {
lua_getglobal(L, luaL_check_string(L, 1));
return 1;
}
static int luaB_tag (lua_State *L) {
luaL_checktype(L, 1, "any");
lua_pushnumber(L, lua_tag(L, 1));
return 1;
}
static int luaB_settag (lua_State *L) {
luaL_checktype(L, 1, "table");
lua_pushvalue(L, 1); /* push table */
lua_settag(L, luaL_check_int(L, 2));
lua_pop(L, 1); /* remove second argument */
return 1; /* return first argument */
}
static int luaB_newtag (lua_State *L) {
lua_pushnumber(L, lua_newtag(L));
return 1;
}
static int luaB_copytagmethods (lua_State *L) {
lua_pushnumber(L, lua_copytagmethods(L, luaL_check_int(L, 1),
luaL_check_int(L, 2)));
return 1;
}
static int luaB_globals (lua_State *L) {
lua_getglobals(L); /* value to be returned */
if (!lua_isnull(L, 1)) {
luaL_checktype(L, 1, "table");
lua_pushvalue(L, 1); /* new table of globals */
lua_setglobals(L);
}
return 1;
}
static int luaB_rawget (lua_State *L) {
luaL_checktype(L, 1, "table");
luaL_checktype(L, 2, "any");
lua_rawget(L, -2);
return 1;
}
static int luaB_rawset (lua_State *L) {
luaL_checktype(L, 1, "table");
luaL_checktype(L, 2, "any");
luaL_checktype(L, 3, "any");
lua_rawset(L, -3);
return 1;
}
static int luaB_settagmethod (lua_State *L) {
int tag = (int)luaL_check_int(L, 1);
const char *event = luaL_check_string(L, 2);
luaL_arg_check(L, lua_isfunction(L, 3) || lua_isnil(L, 3), 3,
"function or nil expected");
lua_pushnil(L); /* to get its tag */
if (strcmp(event, "gc") == 0 && tag != lua_tag(L, -1))
lua_error(L, "deprecated use: cannot set the `gc' tag method from Lua");
lua_pop(L, 1); /* remove the nil */
lua_settagmethod(L, tag, event);
return 1;
}
static int luaB_gettagmethod (lua_State *L) {
lua_gettagmethod(L, luaL_check_int(L, 1), luaL_check_string(L, 2));
return 1;
}
static int luaB_collectgarbage (lua_State *L) {
lua_pushnumber(L, lua_collectgarbage(L, luaL_opt_int(L, 1, 0)));
return 1;
}
static int luaB_type (lua_State *L) {
luaL_checktype(L, 1, "any");
lua_pushstring(L, lua_type(L, 1));
return 1;
}
static int luaB_next (lua_State *L) {
luaL_checktype(L, 1, "table");
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 passresults (lua_State *L, int status, int oldtop) {
if (status == 0) {
int nresults = lua_gettop(L) - oldtop;
if (nresults > 0)
return nresults; /* results are already on the stack */
else {
lua_pushuserdata(L, NULL); /* at least one result to signal no errors */
return 1;
}
}
else { /* error */
lua_pushnil(L);
lua_pushnumber(L, status); /* error code */
return 2;
}
}
static int luaB_dostring (lua_State *L) {
int oldtop = lua_gettop(L);
size_t l;
const char *s = luaL_check_lstr(L, 1, &l);
if (*s == '\27') /* binary files start with ESC... */
lua_error(L, "`dostring' cannot run pre-compiled code");
return passresults(L, lua_dobuffer(L, s, l, luaL_opt_string(L, 2, s)), oldtop);
}
static int luaB_dofile (lua_State *L) {
int oldtop = lua_gettop(L);
const char *fname = luaL_opt_string(L, 1, NULL);
return passresults(L, lua_dofile(L, fname), oldtop);
}
static int luaB_call (lua_State *L) {
int oldtop;
const char *options = luaL_opt_string(L, 3, "");
int err = 0; /* index of old error method */
int i, status;
int n;
luaL_checktype(L, 2, "table");
n = lua_getn(L, 2);
if (!lua_isnull(L, 4)) { /* set new error method */
lua_getglobal(L, LUA_ERRORMESSAGE);
err = lua_gettop(L); /* get index */
lua_pushvalue(L, 4);
lua_setglobal(L, LUA_ERRORMESSAGE);
}
oldtop = lua_gettop(L); /* top before function-call preparation */
/* push function */
lua_pushvalue(L, 1);
luaL_checkstack(L, n, "too many arguments");
for (i=0; i<n; i++) /* push arg[1...n] */
lua_rawgeti(L, 2, i+1);
status = lua_call(L, n, LUA_MULTRET);
if (err != 0) { /* restore old error method */
lua_pushvalue(L, err);
lua_setglobal(L, LUA_ERRORMESSAGE);
}
if (status != 0) { /* error in call? */
if (strchr(options, 'x'))
lua_pushnil(L); /* return nil to signal the error */
else
lua_error(L, NULL); /* propagate error without additional messages */
return 1;
}
if (strchr(options, 'p')) /* pack results? */
lua_error(L, "deprecated option `p' in `call'");
return lua_gettop(L) - oldtop; /* results are already on the stack */
}
static int luaB_tostring (lua_State *L) {
char buff[64];
switch (lua_type(L, 1)[2]) {
case 'm': /* nuMber */
lua_pushstring(L, lua_tostring(L, 1));
return 1;
case 'r': /* stRing */
lua_pushvalue(L, 1);
return 1;
case 'b': /* taBle */
sprintf(buff, "table: %p", lua_topointer(L, 1));
break;
case 'n': /* fuNction */
sprintf(buff, "function: %p", lua_topointer(L, 1));
break;
case 'e': /* usErdata */
sprintf(buff, "userdata(%d): %p", lua_tag(L, 1), lua_touserdata(L, 1));
break;
case 'l': /* niL */
lua_pushstring(L, "nil");
return 1;
default:
luaL_argerror(L, 1, "value expected");
}
lua_pushstring(L, buff);
return 1;
}
static int luaB_foreachi (lua_State *L) {
int n, i;
luaL_checktype(L, 1, "table");
luaL_checktype(L, 2, "function");
n = lua_getn(L, 1);
for (i=1; i<=n; i++) {
lua_pushvalue(L, 2); /* function */
lua_pushnumber(L, i); /* 1st argument */
lua_rawgeti(L, 1, i); /* 2nd argument */
if (lua_call(L, 2, 1) != 0)
lua_error(L, NULL);
if (!lua_isnil(L, -1))
return 1;
lua_pop(L, 1); /* remove nil result */
}
return 0;
}
static int luaB_foreach (lua_State *L) {
luaL_checktype(L, 1, "table");
luaL_checktype(L, 2, "function");
lua_pushnil(L); /* first index */
for (;;) {
if (lua_next(L, 1) == 0)
return 0;
lua_pushvalue(L, 2); /* function */
lua_pushvalue(L, -3); /* key */
lua_pushvalue(L, -3); /* value */
if (lua_call(L, 2, 1) != 0) lua_error(L, NULL);
if (!lua_isnil(L, -1))
return 1;
lua_pop(L, 2); /* remove value and result */
}
}
static int luaB_assert (lua_State *L) {
luaL_checktype(L, 1, "any");
if (lua_isnil(L, 1))
luaL_verror(L, "assertion failed! %.90s", luaL_opt_string(L, 2, ""));
return 0;
}
static int luaB_getn (lua_State *L) {
luaL_checktype(L, 1, "table");
lua_pushnumber(L, lua_getn(L, 1));
return 1;
}
static int luaB_tinsert (lua_State *L) {
int v = lua_gettop(L); /* last argument: to be inserted */
int n, pos;
luaL_checktype(L, 1, "table");
n = lua_getn(L, 1);
if (v == 2) /* called with only 2 arguments */
pos = n+1;
else
pos = luaL_check_int(L, 2); /* 2nd argument is the position */
lua_pushstring(L, "n");
lua_pushnumber(L, n+1);
lua_rawset(L, 1); /* t.n = n+1 */
for (; n>=pos; n--) {
lua_rawgeti(L, 1, n);
lua_rawseti(L, 1, n+1); /* t[n+1] = t[n] */
}
lua_pushvalue(L, v);
lua_rawseti(L, 1, pos); /* t[pos] = v */
return 0;
}
static int luaB_tremove (lua_State *L) {
int pos, n;
luaL_checktype(L, 1, "table");
n = lua_getn(L, 1);
pos = luaL_opt_int(L, 2, n);
if (n <= 0) return 0; /* table is "empty" */
lua_rawgeti(L, 1, pos); /* result = t[pos] */
for ( ;pos<n; pos++) {
lua_rawgeti(L, 1, pos+1);
lua_rawseti(L, 1, pos); /* a[pos] = a[pos+1] */
}
lua_pushstring(L, "n");
lua_pushnumber(L, n-1);
lua_rawset(L, 1); /* t.n = n-1 */
lua_pushnil(L);
lua_rawseti(L, 1, n); /* t[n] = nil */
return 1;
}
/*
** {======================================================
** Quicksort
** (based on `Algorithms in MODULA-3', Robert Sedgewick;
** Addison-Wesley, 1993.)
*/
static void swap (lua_State *L, int i, int j) {
lua_rawgeti(L, 1, i);
lua_rawgeti(L, 1, j);
lua_rawseti(L, 1, i);
lua_rawseti(L, 1, j);
}
static int sort_comp (lua_State *L, int n, int r) {
/* WARNING: the caller (auxsort) must ensure stack space */
int res;
if (!lua_isnil(L, 2)) { /* function? */
lua_pushvalue(L, 2);
if (r) {
lua_rawgeti(L, 1, n); /* a[n] */
lua_pushvalue(L, -3); /* pivot */
}
else {
lua_pushvalue(L, -2); /* pivot */
lua_rawgeti(L, 1, n); /* a[n] */
}
if (lua_call(L, 2, 1) != 0) lua_error(L, NULL);
res = !lua_isnil(L, -1);
}
else { /* a < b? */
lua_rawgeti(L, 1, n); /* a[n] */
if (r)
res = lua_lessthan(L, -1, -2);
else
res = lua_lessthan(L, -2, -1);
}
lua_pop(L, 1);
return res;
}
static void auxsort (lua_State *L, int l, int u) {
while (l < u) { /* for tail recursion */
int i, j;
luaL_checkstack(L, 4, "array too large");
/* sort elements a[l], a[(l+u)/2] and a[u] */
lua_rawgeti(L, 1, u);
if (sort_comp(L, l, 0)) /* a[u] < a[l]? */
swap(L, l, u);
lua_pop(L, 1);
if (u-l == 1) break; /* only 2 elements */
i = (l+u)/2;
lua_rawgeti(L, 1, i); /* Pivot = a[i] */
if (sort_comp(L, l, 0)) /* a[i]<a[l]? */
swap(L, l, i);
else {
if (sort_comp(L, u, 1)) /* a[u]<a[i]? */
swap(L, i, u);
}
lua_pop(L, 1); /* pop old a[i] */
if (u-l == 2) break; /* only 3 elements */
lua_rawgeti(L, 1, i); /* Pivot */
swap(L, i, u-1); /* put median element as pivot (a[u-1]) */
/* a[l] <= P == a[u-1] <= a[u], only needs to sort from l+1 to u-2 */
i = l; j = u-1;
for (;;) { /* invariant: a[l..i] <= P <= a[j..u] */
/* repeat i++ until a[i] >= P */
while (sort_comp(L, ++i, 1))
if (i>u) lua_error(L, "invalid order function for sorting");
/* repeat j-- until a[j] <= P */
while (sort_comp(L, --j, 0))
if (j<l) lua_error(L, "invalid order function for sorting");
if (j<i) break;
swap(L, i, j);
}
swap(L, u-1, i); /* swap pivot (a[u-1]) with a[i] */
/* a[l..i-1] <= a[i] == P <= a[i+1..u] */
/* adjust so that smaller "half" is in [j..i] and larger one in [l..u] */
if (i-l < u-i) {
j=l; i=i-1; l=i+2;
}
else {
j=i+1; i=u; u=j-2;
}
lua_pop(L, 1); /* remove pivot from stack */
auxsort(L, j, i); /* call recursively the smaller one */
} /* repeat the routine for the larger one */
}
static int luaB_sort (lua_State *L) {
int n;
luaL_checktype(L, 1, "table");
n = lua_getn(L, 1);
if (!lua_isnull(L, 2)) /* is there a 2nd argument? */
luaL_checktype(L, 2, "function");
lua_settop(L, 2); /* make sure there is two arguments */
auxsort(L, 1, n);
return 0;
}
/* }====================================================== */
/*
** {======================================================
** Deprecated functions to manipulate global environment.
** =======================================================
*/
/*
** gives an explicit error in any attempt to call a deprecated function
*/
static int deprecated_func (lua_State *L) {
luaL_verror(L, "function `%.20s' is deprecated", luaL_check_string(L, -1));
return 0; /* to avoid warnings */
}
#define num_deprecated 4
static const char *const deprecated_names [num_deprecated] = {
"foreachvar", "nextvar", "rawgetglobal", "rawsetglobal"
};
static void deprecated_funcs (lua_State *L) {
int i;
for (i=0; i<num_deprecated; i++) {
lua_pushstring(L, deprecated_names[i]);
lua_pushcclosure(L, deprecated_func, 1);
lua_setglobal(L, deprecated_names[i]);
}
}
/* }====================================================== */
static const struct luaL_reg base_funcs[] = {
{LUA_ALERT, luaB__ALERT},
{LUA_ERRORMESSAGE, luaB__ERRORMESSAGE},
{"call", luaB_call},
{"collectgarbage", luaB_collectgarbage},
{"copytagmethods", luaB_copytagmethods},
{"dofile", luaB_dofile},
{"dostring", luaB_dostring},
{"error", luaB_error},
{"foreach", luaB_foreach},
{"foreachi", luaB_foreachi},
{"getglobal", luaB_getglobal},
{"gettagmethod", luaB_gettagmethod},
{"globals", luaB_globals},
{"newtag", luaB_newtag},
{"next", luaB_next},
{"print", luaB_print},
{"rawget", luaB_rawget},
{"rawset", luaB_rawset},
{"rawgettable", luaB_rawget}, /* for compatibility */
{"rawsettable", luaB_rawset}, /* for compatibility */
{"setglobal", luaB_setglobal},
{"settag", luaB_settag},
{"settagmethod", luaB_settagmethod},
{"tag", luaB_tag},
{"tonumber", luaB_tonumber},
{"tostring", luaB_tostring},
{"type", luaB_type},
{"assert", luaB_assert},
{"getn", luaB_getn},
{"sort", luaB_sort},
{"tinsert", luaB_tinsert},
{"tremove", luaB_tremove}
};
void lua_baselibopen (lua_State *L) {
luaL_openl(L, base_funcs);
lua_pushstring(L, LUA_VERSION);
lua_setglobal(L, "_VERSION");
deprecated_funcs(L);
}