liolib.c
(5.0.3)
/*
** $Id: liolib.c,v 2.39b 2003/03/19 21:16:12 roberto Exp $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
#include <errno.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#define liolib_c
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
typedef struct FileHandle {
FILE *f;
int ispipe;
} FileHandle;
/*
** by default, gcc does not get `tmpname'
*/
#ifndef USE_TMPNAME
#ifdef __GNUC__
#define USE_TMPNAME 0
#else
#define USE_TMPNAME 1
#endif
#endif
/*
** by default, posix systems get `popen'
*/
#ifndef USE_POPEN
#ifdef _POSIX_C_SOURCE
#if _POSIX_C_SOURCE >= 2
#define USE_POPEN 1
#endif
#endif
#endif
#ifndef USE_POPEN
#define USE_POPEN 0
#endif
/*
** {======================================================
** FILE Operations
** =======================================================
*/
#if !USE_POPEN
#define pclose(f) (-1)
#endif
#define FILEHANDLE "FILE*"
#define IO_INPUT "_input"
#define IO_OUTPUT "_output"
static int pushresult (lua_State *L, int i, const char *filename) {
if (i) {
lua_pushboolean(L, 1);
return 1;
}
else {
lua_pushnil(L);
if (filename)
lua_pushfstring(L, "%s: %s", filename, strerror(errno));
else
lua_pushfstring(L, "%s", strerror(errno));
lua_pushnumber(L, errno);
return 3;
}
}
static FileHandle *topfile (lua_State *L, int findex) {
FileHandle *fh = (FileHandle *)luaL_checkudata(L, findex, FILEHANDLE);
if (fh == NULL) luaL_argerror(L, findex, "bad file");
return fh;
}
static int io_type (lua_State *L) {
FileHandle *fh = (FileHandle *)luaL_checkudata(L, 1, FILEHANDLE);
if (fh == NULL) lua_pushnil(L);
else if (fh->f == NULL)
lua_pushliteral(L, "closed file");
else
lua_pushliteral(L, "file");
return 1;
}
#define tofile(L,i) (tofileh(L,i)->f)
static FileHandle *tofileh (lua_State *L, int findex) {
FileHandle *fh = topfile(L, findex);
if (fh->f == NULL)
luaL_error(L, "attempt to use a closed file");
return fh;
}
#define newfile(L) (&(newfileh(L)->f))
/*
** When creating file handles, always creates a `closed' file handle
** before opening the actual file; so, if there is a memory error, the
** file is not left opened.
*/
static FileHandle *newfileh (lua_State *L) {
FileHandle *fh = (FileHandle *)lua_newuserdata(L, sizeof(FileHandle));
fh->f = NULL; /* file handle is currently `closed' */
fh->ispipe = 0;
luaL_getmetatable(L, FILEHANDLE);
lua_setmetatable(L, -2);
return fh;
}
/*
** assumes that top of the stack is the `io' library, and next is
** the `io' metatable
*/
static void registerfile (lua_State *L, FILE *f, const char *name,
const char *impname) {
lua_pushstring(L, name);
*newfile(L) = f;
if (impname) {
lua_pushstring(L, impname);
lua_pushvalue(L, -2);
lua_settable(L, -6); /* metatable[impname] = file */
}
lua_settable(L, -3); /* io[name] = file */
}
static int aux_close (lua_State *L) {
FileHandle *fh = tofileh(L, 1);
FILE *f = fh->f;
if (f == stdin || f == stdout || f == stderr)
return 0; /* file cannot be closed */
else {
int ok = fh->ispipe ? (pclose(f) != -1) : (fclose(f) == 0);
fh->f = NULL; /* mark file as closed */
return ok;
}
}
static int io_close (lua_State *L) {
if (lua_isnone(L, 1) && lua_type(L, lua_upvalueindex(1)) == LUA_TTABLE) {
lua_pushstring(L, IO_OUTPUT);
lua_rawget(L, lua_upvalueindex(1));
}
return pushresult(L, aux_close(L), NULL);
}
static int io_gc (lua_State *L) {
FileHandle *fh = topfile(L, 1);
if (fh->f != NULL) /* ignore closed files */
aux_close(L);
return 0;
}
static int io_tostring (lua_State *L) {
char buff[128];
FileHandle *fh = topfile(L, 1);
if (fh->f == NULL)
strcpy(buff, "closed");
else
sprintf(buff, "%p", lua_touserdata(L, 1));
lua_pushfstring(L, "file (%s)", buff);
return 1;
}
static int io_open (lua_State *L) {
const char *filename = luaL_checkstring(L, 1);
const char *mode = luaL_optstring(L, 2, "r");
FILE **pf = newfile(L);
*pf = fopen(filename, mode);
return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
}
static int io_popen (lua_State *L) {
#if !USE_POPEN
luaL_error(L, "`popen' not supported");
return 0;
#else
const char *filename = luaL_checkstring(L, 1);
const char *mode = luaL_optstring(L, 2, "r");
FileHandle *fh = newfileh(L);
fh->f = popen(filename, mode);
fh->ispipe = 1;
return (fh->f == NULL) ? pushresult(L, 0, filename) : 1;
#endif
}
static int io_tmpfile (lua_State *L) {
FILE **pf = newfile(L);
*pf = tmpfile();
return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
}
static FILE *getiofile (lua_State *L, const char *name) {
lua_pushstring(L, name);
lua_rawget(L, lua_upvalueindex(1));
return tofile(L, -1);
}
static int g_iofile (lua_State *L, const char *name, const char *mode) {
if (!lua_isnoneornil(L, 1)) {
const char *filename = lua_tostring(L, 1);
lua_pushstring(L, name);
if (filename) {
FILE **pf = newfile(L);
*pf = fopen(filename, mode);
if (*pf == NULL) {
lua_pushfstring(L, "%s: %s", filename, strerror(errno));
luaL_argerror(L, 1, lua_tostring(L, -1));
}
}
else {
tofile(L, 1); /* check that it's a valid file handle */
lua_pushvalue(L, 1);
}
lua_rawset(L, lua_upvalueindex(1));
}
/* return current value */
lua_pushstring(L, name);
lua_rawget(L, lua_upvalueindex(1));
return 1;
}
static int io_input (lua_State *L) {
return g_iofile(L, IO_INPUT, "r");
}
static int io_output (lua_State *L) {
return g_iofile(L, IO_OUTPUT, "w");
}
static int io_readline (lua_State *L);
static void aux_lines (lua_State *L, int idx, int close) {
lua_pushliteral(L, FILEHANDLE);
lua_rawget(L, LUA_REGISTRYINDEX);
lua_pushvalue(L, idx);
lua_pushboolean(L, close); /* close/not close file when finished */
lua_pushcclosure(L, io_readline, 3);
}
static int f_lines (lua_State *L) {
tofile(L, 1); /* check that it's a valid file handle */
aux_lines(L, 1, 0);
return 1;
}
static int io_lines (lua_State *L) {
if (lua_isnoneornil(L, 1)) { /* no arguments? */
lua_pushstring(L, IO_INPUT);
lua_rawget(L, lua_upvalueindex(1)); /* will iterate over default input */
return f_lines(L);
}
else {
const char *filename = luaL_checkstring(L, 1);
FILE **pf = newfile(L);
*pf = fopen(filename, "r");
luaL_argcheck(L, *pf, 1, strerror(errno));
aux_lines(L, lua_gettop(L), 1);
return 1;
}
}
/*
** {======================================================
** READ
** =======================================================
*/
static int read_number (lua_State *L, FILE *f) {
lua_Number d;
if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
lua_pushnumber(L, d);
return 1;
}
else return 0; /* read fails */
}
static int test_eof (lua_State *L, FILE *f) {
int c = getc(f);
ungetc(c, f);
lua_pushlstring(L, NULL, 0);
return (c != EOF);
}
static int read_line (lua_State *L, FILE *f) {
luaL_Buffer b;
luaL_buffinit(L, &b);
for (;;) {
size_t l;
char *p = luaL_prepbuffer(&b);
if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) { /* eof? */
luaL_pushresult(&b); /* close buffer */
return (lua_strlen(L, -1) > 0); /* check whether read something */
}
l = strlen(p);
if (p[l-1] != '\n')
luaL_addsize(&b, l);
else {
luaL_addsize(&b, l - 1); /* do not include `eol' */
luaL_pushresult(&b); /* close buffer */
return 1; /* read at least an `eol' */
}
}
}
static int read_chars (lua_State *L, FILE *f, size_t n) {
size_t rlen; /* how much to read */
size_t nr; /* number of chars actually read */
luaL_Buffer b;
luaL_buffinit(L, &b);
rlen = LUAL_BUFFERSIZE; /* try to read that much each time */
do {
char *p = luaL_prepbuffer(&b);
if (rlen > n) rlen = n; /* cannot read more than asked */
nr = fread(p, sizeof(char), rlen, f);
luaL_addsize(&b, nr);
n -= nr; /* still have to read `n' chars */
} while (n > 0 && nr == rlen); /* until end of count or eof */
luaL_pushresult(&b); /* close buffer */
return (n == 0 || lua_strlen(L, -1) > 0);
}
static int g_read (lua_State *L, FILE *f, int first) {
int nargs = lua_gettop(L) - 1;
int success;
int n;
if (nargs == 0) { /* no arguments? */
success = read_line(L, f);
n = first+1; /* to return 1 result */
}
else { /* ensure stack space for all results and for auxlib's buffer */
luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
success = 1;
for (n = first; nargs-- && success; n++) {
if (lua_type(L, n) == LUA_TNUMBER) {
size_t l = (size_t)lua_tonumber(L, n);
success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
}
else {
const char *p = lua_tostring(L, n);
luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
switch (p[1]) {
case 'n': /* number */
success = read_number(L, f);
break;
case 'l': /* line */
success = read_line(L, f);
break;
case 'a': /* file */
read_chars(L, f, ~((size_t)0)); /* read MAX_SIZE_T chars */
success = 1; /* always success */
break;
case 'w': /* word */
return luaL_error(L, "obsolete option `*w' to `read'");
default:
return luaL_argerror(L, n, "invalid format");
}
}
}
}
if (!success) {
lua_pop(L, 1); /* remove last result */
lua_pushnil(L); /* push nil instead */
}
return n - first;
}
static int io_read (lua_State *L) {
return g_read(L, getiofile(L, IO_INPUT), 1);
}
static int f_read (lua_State *L) {
return g_read(L, tofile(L, 1), 2);
}
static int io_readline (lua_State *L) {
FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(2));
if (f == NULL) /* file is already closed? */
luaL_error(L, "file is already closed");
if (read_line(L, f)) return 1;
else { /* EOF */
if (lua_toboolean(L, lua_upvalueindex(3))) { /* generator created file? */
lua_settop(L, 0);
lua_pushvalue(L, lua_upvalueindex(2));
aux_close(L); /* close it */
}
return 0;
}
}
/* }====================================================== */
static int g_write (lua_State *L, FILE *f, int arg) {
int nargs = lua_gettop(L) - 1;
int status = 1;
for (; nargs--; arg++) {
if (lua_type(L, arg) == LUA_TNUMBER) {
/* optimization: could be done exactly as for strings */
status = status &&
fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
}
else {
size_t l;
const char *s = luaL_checklstring(L, arg, &l);
status = status && (fwrite(s, sizeof(char), l, f) == l);
}
}
return pushresult(L, status, NULL);
}
static int io_write (lua_State *L) {
return g_write(L, getiofile(L, IO_OUTPUT), 1);
}
static int f_write (lua_State *L) {
return g_write(L, tofile(L, 1), 2);
}
static int f_seek (lua_State *L) {
static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
static const char *const modenames[] = {"set", "cur", "end", NULL};
FILE *f = tofile(L, 1);
int op = luaL_findstring(luaL_optstring(L, 2, "cur"), modenames);
long offset = luaL_optlong(L, 3, 0);
luaL_argcheck(L, op != -1, 2, "invalid mode");
op = fseek(f, offset, mode[op]);
if (op)
return pushresult(L, 0, NULL); /* error */
else {
lua_pushnumber(L, ftell(f));
return 1;
}
}
static int io_flush (lua_State *L) {
return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
}
static int f_flush (lua_State *L) {
return pushresult(L, fflush(tofile(L, 1)) == 0, NULL);
}
static const luaL_reg iolib[] = {
{"input", io_input},
{"output", io_output},
{"lines", io_lines},
{"close", io_close},
{"flush", io_flush},
{"open", io_open},
{"popen", io_popen},
{"read", io_read},
{"tmpfile", io_tmpfile},
{"type", io_type},
{"write", io_write},
{NULL, NULL}
};
static const luaL_reg flib[] = {
{"flush", f_flush},
{"read", f_read},
{"lines", f_lines},
{"seek", f_seek},
{"write", f_write},
{"close", io_close},
{"__gc", io_gc},
{"__tostring", io_tostring},
{NULL, NULL}
};
static void createmeta (lua_State *L) {
luaL_newmetatable(L, FILEHANDLE); /* create new metatable for file handles */
/* file methods */
lua_pushliteral(L, "__index");
lua_pushvalue(L, -2); /* push metatable */
lua_rawset(L, -3); /* metatable.__index = metatable */
luaL_openlib(L, NULL, flib, 0);
}
/* }====================================================== */
/*
** {======================================================
** Other O.S. Operations
** =======================================================
*/
static int io_execute (lua_State *L) {
lua_pushnumber(L, system(luaL_checkstring(L, 1)));
return 1;
}
static int io_remove (lua_State *L) {
const char *filename = luaL_checkstring(L, 1);
return pushresult(L, remove(filename) == 0, filename);
}
static int io_rename (lua_State *L) {
const char *fromname = luaL_checkstring(L, 1);
const char *toname = luaL_checkstring(L, 2);
return pushresult(L, rename(fromname, toname) == 0, fromname);
}
static int io_tmpname (lua_State *L) {
#if !USE_TMPNAME
luaL_error(L, "`tmpname' not supported");
return 0;
#else
char buff[L_tmpnam];
if (tmpnam(buff) != buff)
return luaL_error(L, "unable to generate a unique filename in `tmpname'");
lua_pushstring(L, buff);
return 1;
#endif
}
static int io_getenv (lua_State *L) {
lua_pushstring(L, getenv(luaL_checkstring(L, 1))); /* if NULL push nil */
return 1;
}
static int io_clock (lua_State *L) {
lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
return 1;
}
/*
** {======================================================
** Time/Date operations
** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
** wday=%w+1, yday=%j, isdst=? }
** =======================================================
*/
static void setfield (lua_State *L, const char *key, int value) {
lua_pushstring(L, key);
lua_pushnumber(L, value);
lua_rawset(L, -3);
}
static void setboolfield (lua_State *L, const char *key, int value) {
lua_pushstring(L, key);
lua_pushboolean(L, value);
lua_rawset(L, -3);
}
static int getboolfield (lua_State *L, const char *key) {
int res;
lua_pushstring(L, key);
lua_gettable(L, -2);
res = lua_toboolean(L, -1);
lua_pop(L, 1);
return res;
}
static int getfield (lua_State *L, const char *key, int d) {
int res;
lua_pushstring(L, key);
lua_gettable(L, -2);
if (lua_isnumber(L, -1))
res = (int)(lua_tonumber(L, -1));
else {
if (d == -2)
return luaL_error(L, "field `%s' missing in date table", key);
res = d;
}
lua_pop(L, 1);
return res;
}
static int io_date (lua_State *L) {
const char *s = luaL_optstring(L, 1, "%c");
time_t t = (time_t)(luaL_optnumber(L, 2, -1));
struct tm *stm;
if (t == (time_t)(-1)) /* no time given? */
t = time(NULL); /* use current time */
if (*s == '!') { /* UTC? */
stm = gmtime(&t);
s++; /* skip `!' */
}
else
stm = localtime(&t);
if (stm == NULL) /* invalid date? */
lua_pushnil(L);
else if (strcmp(s, "*t") == 0) {
lua_newtable(L);
setfield(L, "sec", stm->tm_sec);
setfield(L, "min", stm->tm_min);
setfield(L, "hour", stm->tm_hour);
setfield(L, "day", stm->tm_mday);
setfield(L, "month", stm->tm_mon+1);
setfield(L, "year", stm->tm_year+1900);
setfield(L, "wday", stm->tm_wday+1);
setfield(L, "yday", stm->tm_yday+1);
setboolfield(L, "isdst", stm->tm_isdst);
}
else {
char b[256];
if (strftime(b, sizeof(b), s, stm))
lua_pushstring(L, b);
else
return luaL_error(L, "`date' format too long");
}
return 1;
}
static int io_time (lua_State *L) {
if (lua_isnoneornil(L, 1)) /* called without args? */
lua_pushnumber(L, time(NULL)); /* return current time */
else {
time_t t;
struct tm ts;
luaL_checktype(L, 1, LUA_TTABLE);
lua_settop(L, 1); /* make sure table is at the top */
ts.tm_sec = getfield(L, "sec", 0);
ts.tm_min = getfield(L, "min", 0);
ts.tm_hour = getfield(L, "hour", 12);
ts.tm_mday = getfield(L, "day", -2);
ts.tm_mon = getfield(L, "month", -2) - 1;
ts.tm_year = getfield(L, "year", -2) - 1900;
ts.tm_isdst = getboolfield(L, "isdst");
t = mktime(&ts);
if (t == (time_t)(-1))
lua_pushnil(L);
else
lua_pushnumber(L, t);
}
return 1;
}
static int io_difftime (lua_State *L) {
lua_pushnumber(L, difftime((time_t)(luaL_checknumber(L, 1)),
(time_t)(luaL_optnumber(L, 2, 0))));
return 1;
}
/* }====================================================== */
static int io_setloc (lua_State *L) {
static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
LC_NUMERIC, LC_TIME};
static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
"numeric", "time", NULL};
const char *l = lua_tostring(L, 1);
int op = luaL_findstring(luaL_optstring(L, 2, "all"), catnames);
luaL_argcheck(L, l || lua_isnoneornil(L, 1), 1, "string expected");
luaL_argcheck(L, op != -1, 2, "invalid option");
lua_pushstring(L, setlocale(cat[op], l));
return 1;
}
static int io_exit (lua_State *L) {
exit(luaL_optint(L, 1, EXIT_SUCCESS));
return 0; /* to avoid warnings */
}
static const luaL_reg syslib[] = {
{"clock", io_clock},
{"date", io_date},
{"difftime", io_difftime},
{"execute", io_execute},
{"exit", io_exit},
{"getenv", io_getenv},
{"remove", io_remove},
{"rename", io_rename},
{"setlocale", io_setloc},
{"time", io_time},
{"tmpname", io_tmpname},
{NULL, NULL}
};
/* }====================================================== */
LUALIB_API int luaopen_io (lua_State *L) {
luaL_openlib(L, LUA_OSLIBNAME, syslib, 0);
createmeta(L);
lua_pushvalue(L, -1);
luaL_openlib(L, LUA_IOLIBNAME, iolib, 1);
/* put predefined file handles into `io' table */
registerfile(L, stdin, "stdin", IO_INPUT);
registerfile(L, stdout, "stdout", IO_OUTPUT);
registerfile(L, stderr, "stderr", NULL);
return 1;
}