liolib.c
(4.0.1)
/*
** $Id: liolib.c,v 1.91 2000/10/31 13:10:24 roberto Exp $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "lua.h"
#include "lauxlib.h"
#include "luadebug.h"
#include "lualib.h"
#ifndef OLD_ANSI
#include <errno.h>
#include <locale.h>
#define realloc(b,s) ((b) == NULL ? malloc(s) : (realloc)(b, s))
#define free(b) if (b) (free)(b)
#else
/* no support for locale and for strerror: fake them */
#define setlocale(a,b) ((void)a, strcmp((b),"C")==0?"C":NULL)
#define LC_ALL 0
#define LC_COLLATE 0
#define LC_CTYPE 0
#define LC_MONETARY 0
#define LC_NUMERIC 0
#define LC_TIME 0
#define strerror(e) "generic I/O error"
#define errno (-1)
#endif
#ifdef POPEN
/* FILE *popen();
int pclose(); */
#define CLOSEFILE(L, f) ((pclose(f) == -1) ? fclose(f) : 0)
#else
/* no support for popen */
#define popen(x,y) NULL /* that is, popen always fails */
#define CLOSEFILE(L, f) (fclose(f))
#endif
#define INFILE 0
#define OUTFILE 1
typedef struct IOCtrl {
int ref[2]; /* ref for strings _INPUT/_OUTPUT */
int iotag; /* tag for file handles */
int closedtag; /* tag for closed handles */
} IOCtrl;
static const char *const filenames[] = {"_INPUT", "_OUTPUT"};
static int pushresult (lua_State *L, int i) {
if (i) {
lua_pushuserdata(L, NULL);
return 1;
}
else {
lua_pushnil(L);
lua_pushstring(L, strerror(errno));
lua_pushnumber(L, errno);
return 3;;
}
}
/*
** {======================================================
** FILE Operations
** =======================================================
*/
static FILE *gethandle (lua_State *L, IOCtrl *ctrl, int f) {
void *p = lua_touserdata(L, f);
if (p != NULL) { /* is `f' a userdata ? */
int ftag = lua_tag(L, f);
if (ftag == ctrl->iotag) /* does it have the correct tag? */
return (FILE *)p;
else if (ftag == ctrl->closedtag)
lua_error(L, "cannot access a closed file");
/* else go through */
}
return NULL;
}
static FILE *getnonullfile (lua_State *L, IOCtrl *ctrl, int arg) {
FILE *f = gethandle(L, ctrl, arg);
luaL_arg_check(L, f, arg, "invalid file handle");
return f;
}
static FILE *getfilebyref (lua_State *L, IOCtrl *ctrl, int inout) {
FILE *f;
lua_getglobals(L);
lua_getref(L, ctrl->ref[inout]);
lua_rawget(L, -2);
f = gethandle(L, ctrl, -1);
if (f == NULL)
luaL_verror(L, "global variable `%.10s' is not a file handle",
filenames[inout]);
return f;
}
static void setfilebyname (lua_State *L, IOCtrl *ctrl, FILE *f,
const char *name) {
lua_pushusertag(L, f, ctrl->iotag);
lua_setglobal(L, name);
}
#define setfile(L,ctrl,f,inout) (setfilebyname(L,ctrl,f,filenames[inout]))
static int setreturn (lua_State *L, IOCtrl *ctrl, FILE *f, int inout) {
if (f == NULL)
return pushresult(L, 0);
else {
setfile(L, ctrl, f, inout);
lua_pushusertag(L, f, ctrl->iotag);
return 1;
}
}
static int closefile (lua_State *L, IOCtrl *ctrl, FILE *f) {
if (f == stdin || f == stdout || f == stderr)
return 1;
else {
lua_pushusertag(L, f, ctrl->iotag);
lua_settag(L, ctrl->closedtag);
return (CLOSEFILE(L, f) == 0);
}
}
static int io_close (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
lua_pop(L, 1); /* remove upvalue */
return pushresult(L, closefile(L, ctrl, getnonullfile(L, ctrl, 1)));
}
static int file_collect (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
FILE *f = getnonullfile(L, ctrl, 1);
if (f != stdin && f != stdout && f != stderr)
CLOSEFILE(L, f);
return 0;
}
static int io_open (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
FILE *f;
lua_pop(L, 1); /* remove upvalue */
f = fopen(luaL_check_string(L, 1), luaL_check_string(L, 2));
if (f) {
lua_pushusertag(L, f, ctrl->iotag);
return 1;
}
else
return pushresult(L, 0);
}
static int io_fromto (lua_State *L, int inout, const char *mode) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
FILE *current;
lua_pop(L, 1); /* remove upvalue */
if (lua_isnull(L, 1)) {
closefile(L, ctrl, getfilebyref(L, ctrl, inout));
current = (inout == 0) ? stdin : stdout;
}
else if (lua_tag(L, 1) == ctrl->iotag) /* deprecated option */
current = (FILE *)lua_touserdata(L, 1);
else {
const char *s = luaL_check_string(L, 1);
current = (*s == '|') ? popen(s+1, mode) : fopen(s, mode);
}
return setreturn(L, ctrl, current, inout);
}
static int io_readfrom (lua_State *L) {
return io_fromto(L, INFILE, "r");
}
static int io_writeto (lua_State *L) {
return io_fromto(L, OUTFILE, "w");
}
static int io_appendto (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
FILE *current;
lua_pop(L, 1); /* remove upvalue */
current = fopen(luaL_check_string(L, 1), "a");
return setreturn(L, ctrl, current, OUTFILE);
}
/*
** {======================================================
** READ
** =======================================================
*/
#ifdef LUA_COMPAT_READPATTERN
/*
** We cannot lookahead without need, because this can lock stdin.
** This flag signals when we need to read a next char.
*/
#define NEED_OTHER (EOF-1) /* just some flag different from EOF */
static int read_pattern (lua_State *L, FILE *f, const char *p) {
int inskip = 0; /* {skip} level */
int c = NEED_OTHER;
luaL_Buffer b;
luaL_buffinit(L, &b);
while (*p != '\0') {
switch (*p) {
case '{':
inskip++;
p++;
continue;
case '}':
if (!inskip) lua_error(L, "unbalanced braces in read pattern");
inskip--;
p++;
continue;
default: {
const char *ep = luaI_classend(L, p); /* get what is next */
int m; /* match result */
if (c == NEED_OTHER) c = getc(f);
m = (c==EOF) ? 0 : luaI_singlematch(c, p, ep);
if (m) {
if (!inskip) luaL_putchar(&b, c);
c = NEED_OTHER;
}
switch (*ep) {
case '+': /* repetition (1 or more) */
if (!m) goto break_while; /* pattern fails? */
/* else go through */
case '*': /* repetition (0 or more) */
while (m) { /* reads the same item until it fails */
c = getc(f);
m = (c==EOF) ? 0 : luaI_singlematch(c, p, ep);
if (m && !inskip) luaL_putchar(&b, c);
}
/* go through to continue reading the pattern */
case '?': /* optional */
p = ep+1; /* continues reading the pattern */
continue;
default:
if (!m) goto break_while; /* pattern fails? */
p = ep; /* else continues reading the pattern */
}
}
}
} break_while:
if (c != NEED_OTHER) ungetc(c, f);
luaL_pushresult(&b); /* close buffer */
return (*p == '\0');
}
#else
#define read_pattern(L, f, p) (lua_error(L, "read patterns are deprecated"), 0)
#endif
static int read_number (lua_State *L, FILE *f) {
double d;
if (fscanf(f, "%lf", &d) == 1) {
lua_pushnumber(L, d);
return 1;
}
else return 0; /* read fails */
}
static int read_word (lua_State *L, FILE *f) {
int c;
luaL_Buffer b;
luaL_buffinit(L, &b);
do { c = fgetc(f); } while (isspace(c)); /* skip spaces */
while (c != EOF && !isspace(c)) {
luaL_putchar(&b, c);
c = fgetc(f);
}
ungetc(c, f);
luaL_pushresult(&b); /* close buffer */
return (lua_strlen(L, -1) > 0);
}
static int read_line (lua_State *L, FILE *f) {
int n = 0;
luaL_Buffer b;
luaL_buffinit(L, &b);
for (;;) {
char *p = luaL_prepbuffer(&b);
if (!fgets(p, LUAL_BUFFERSIZE, f)) /* read fails? */
break;
n = strlen(p);
if (p[n-1] != '\n')
luaL_addsize(&b, n);
else {
luaL_addsize(&b, n-1); /* do not add the `\n' */
break;
}
}
luaL_pushresult(&b); /* close buffer */
return (n > 0); /* read something? */
}
static void read_file (lua_State *L, FILE *f) {
size_t len = 0;
size_t size = BUFSIZ;
char *buffer = NULL;
for (;;) {
char *newbuffer = (char *)realloc(buffer, size);
if (newbuffer == NULL) {
free(buffer);
lua_error(L, "not enough memory to read a file");
}
buffer = newbuffer;
len += fread(buffer+len, sizeof(char), size-len, f);
if (len < size) break; /* did not read all it could */
size *= 2;
}
lua_pushlstring(L, buffer, len);
free(buffer);
}
static int read_chars (lua_State *L, FILE *f, size_t n) {
char *buffer;
size_t n1;
char statbuff[BUFSIZ];
if (n <= BUFSIZ)
buffer = statbuff;
else {
buffer = (char *)malloc(n);
if (buffer == NULL)
lua_error(L, "not enough memory to read a file");
}
n1 = fread(buffer, sizeof(char), n, f);
lua_pushlstring(L, buffer, n1);
if (buffer != statbuff) free(buffer);
return (n1 > 0 || n == 0);
}
static int io_read (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
int lastarg = lua_gettop(L) - 1;
int firstarg = 1;
FILE *f = gethandle(L, ctrl, firstarg);
int n;
if (f) firstarg++;
else f = getfilebyref(L, ctrl, INFILE); /* get _INPUT */
lua_pop(L, 1);
if (firstarg > lastarg) { /* no arguments? */
lua_settop(L, 0); /* erase upvalue and other eventual garbage */
firstarg = lastarg = 1; /* correct indices */
lua_pushstring(L, "*l"); /* push default argument */
}
else /* ensure stack space for all results and for auxlib's buffer */
luaL_checkstack(L, lastarg-firstarg+1+LUA_MINSTACK, "too many arguments");
for (n = firstarg; n<=lastarg; n++) {
int success;
if (lua_isnumber(L, n))
success = read_chars(L, f, (size_t)lua_tonumber(L, n));
else {
const char *p = luaL_check_string(L, n);
if (p[0] != '*')
success = read_pattern(L, f, p); /* deprecated! */
else {
switch (p[1]) {
case 'n': /* number */
if (!read_number(L, f)) goto endloop; /* read fails */
continue; /* number is already pushed; avoid the "pushstring" */
case 'l': /* line */
success = read_line(L, f);
break;
case 'a': /* file */
read_file(L, f);
success = 1; /* always success */
break;
case 'w': /* word */
success = read_word(L, f);
break;
default:
luaL_argerror(L, n, "invalid format");
success = 0; /* to avoid warnings */
}
}
}
if (!success) {
lua_pop(L, 1); /* remove last result */
break; /* read fails */
}
} endloop:
return n - firstarg;
}
/* }====================================================== */
static int io_write (lua_State *L) {
int lastarg = lua_gettop(L) - 1;
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
int arg = 1;
int status = 1;
FILE *f = gethandle(L, ctrl, arg);
if (f) arg++;
else f = getfilebyref(L, ctrl, OUTFILE); /* get _OUTPUT */
for (; arg <= lastarg; arg++) {
if (lua_type(L, arg) == LUA_TNUMBER) { /* LUA_NUMBER */
/* optimization: could be done exactly as for strings */
status = status && fprintf(f, "%.16g", lua_tonumber(L, arg)) > 0;
}
else {
size_t l;
const char *s = luaL_check_lstr(L, arg, &l);
status = status && (fwrite(s, sizeof(char), l, f) == l);
}
}
pushresult(L, status);
return 1;
}
static int io_seek (lua_State *L) {
static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
static const char *const modenames[] = {"set", "cur", "end", NULL};
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
FILE *f;
int op;
long offset;
lua_pop(L, 1); /* remove upvalue */
f = getnonullfile(L, ctrl, 1);
op = luaL_findstring(luaL_opt_string(L, 2, "cur"), modenames);
offset = luaL_opt_long(L, 3, 0);
luaL_arg_check(L, op != -1, 2, "invalid mode");
op = fseek(f, offset, mode[op]);
if (op)
return pushresult(L, 0); /* error */
else {
lua_pushnumber(L, ftell(f));
return 1;
}
}
static int io_flush (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_touserdata(L, -1);
FILE *f;
lua_pop(L, 1); /* remove upvalue */
f = gethandle(L, ctrl, 1);
luaL_arg_check(L, f || lua_isnull(L, 1), 1, "invalid file handle");
return pushresult(L, fflush(f) == 0);
}
/* }====================================================== */
/*
** {======================================================
** Other O.S. Operations
** =======================================================
*/
static int io_execute (lua_State *L) {
lua_pushnumber(L, system(luaL_check_string(L, 1)));
return 1;
}
static int io_remove (lua_State *L) {
return pushresult(L, remove(luaL_check_string(L, 1)) == 0);
}
static int io_rename (lua_State *L) {
return pushresult(L, rename(luaL_check_string(L, 1),
luaL_check_string(L, 2)) == 0);
}
static int io_tmpname (lua_State *L) {
lua_pushstring(L, tmpnam(NULL));
return 1;
}
static int io_getenv (lua_State *L) {
lua_pushstring(L, getenv(luaL_check_string(L, 1))); /* if NULL push nil */
return 1;
}
static int io_clock (lua_State *L) {
lua_pushnumber(L, ((double)clock())/CLOCKS_PER_SEC);
return 1;
}
static int io_date (lua_State *L) {
char b[256];
const char *s = luaL_opt_string(L, 1, "%c");
struct tm *stm;
time_t t;
time(&t); stm = localtime(&t);
if (strftime(b, sizeof(b), s, stm))
lua_pushstring(L, b);
else
lua_error(L, "invalid `date' format");
return 1;
}
static int 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};
int op = luaL_findstring(luaL_opt_string(L, 2, "all"), catnames);
luaL_arg_check(L, op != -1, 2, "invalid option");
lua_pushstring(L, setlocale(cat[op], luaL_check_string(L, 1)));
return 1;
}
static int io_exit (lua_State *L) {
exit(luaL_opt_int(L, 1, EXIT_SUCCESS));
return 0; /* to avoid warnings */
}
/* }====================================================== */
static int io_debug (lua_State *L) {
for (;;) {
char buffer[250];
fprintf(stderr, "lua_debug> ");
if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
strcmp(buffer, "cont\n") == 0)
return 0;
lua_dostring(L, buffer);
lua_settop(L, 0); /* remove eventual returns */
}
}
#define LEVELS1 12 /* size of the first part of the stack */
#define LEVELS2 10 /* size of the second part of the stack */
static int errorfb (lua_State *L) {
int level = 1; /* skip level 0 (it's this function) */
int firstpart = 1; /* still before eventual `...' */
lua_Debug ar;
luaL_Buffer b;
luaL_buffinit(L, &b);
luaL_addstring(&b, "error: ");
luaL_addstring(&b, luaL_check_string(L, 1));
luaL_addstring(&b, "\n");
while (lua_getstack(L, level++, &ar)) {
char buff[120]; /* enough to fit following `sprintf's */
if (level == 2)
luaL_addstring(&b, "stack traceback:\n");
else if (level > LEVELS1 && firstpart) {
/* no more than `LEVELS2' more levels? */
if (!lua_getstack(L, level+LEVELS2, &ar))
level--; /* keep going */
else {
luaL_addstring(&b, " ...\n"); /* too many levels */
while (lua_getstack(L, level+LEVELS2, &ar)) /* find last levels */
level++;
}
firstpart = 0;
continue;
}
sprintf(buff, "%4d: ", level-1);
luaL_addstring(&b, buff);
lua_getinfo(L, "Snl", &ar);
switch (*ar.namewhat) {
case 'g': case 'l': /* global, local */
sprintf(buff, "function `%.50s'", ar.name);
break;
case 'f': /* field */
sprintf(buff, "method `%.50s'", ar.name);
break;
case 't': /* tag method */
sprintf(buff, "`%.50s' tag method", ar.name);
break;
default: {
if (*ar.what == 'm') /* main? */
sprintf(buff, "main of %.70s", ar.short_src);
else if (*ar.what == 'C') /* C function? */
sprintf(buff, "%.70s", ar.short_src);
else
sprintf(buff, "function <%d:%.70s>", ar.linedefined, ar.short_src);
ar.source = NULL; /* do not print source again */
}
}
luaL_addstring(&b, buff);
if (ar.currentline > 0) {
sprintf(buff, " at line %d", ar.currentline);
luaL_addstring(&b, buff);
}
if (ar.source) {
sprintf(buff, " [%.70s]", ar.short_src);
luaL_addstring(&b, buff);
}
luaL_addstring(&b, "\n");
}
luaL_pushresult(&b);
lua_getglobal(L, LUA_ALERT);
if (lua_isfunction(L, -1)) { /* avoid loop if _ALERT is not defined */
lua_pushvalue(L, -2); /* error message */
lua_rawcall(L, 1, 0);
}
return 0;
}
static const struct luaL_reg iolib[] = {
{LUA_ERRORMESSAGE, errorfb},
{"clock", io_clock},
{"date", io_date},
{"debug", io_debug},
{"execute", io_execute},
{"exit", io_exit},
{"getenv", io_getenv},
{"remove", io_remove},
{"rename", io_rename},
{"setlocale", setloc},
{"tmpname", io_tmpname}
};
static const struct luaL_reg iolibtag[] = {
{"appendto", io_appendto},
{"closefile", io_close},
{"flush", io_flush},
{"openfile", io_open},
{"read", io_read},
{"readfrom", io_readfrom},
{"seek", io_seek},
{"write", io_write},
{"writeto", io_writeto}
};
static void openwithcontrol (lua_State *L) {
IOCtrl *ctrl = (IOCtrl *)lua_newuserdata(L, sizeof(IOCtrl));
unsigned int i;
ctrl->iotag = lua_newtag(L);
ctrl->closedtag = lua_newtag(L);
for (i=0; i<sizeof(iolibtag)/sizeof(iolibtag[0]); i++) {
/* put `ctrl' as upvalue for these functions */
lua_pushvalue(L, -1);
lua_pushcclosure(L, iolibtag[i].func, 1);
lua_setglobal(L, iolibtag[i].name);
}
/* create references to variable names */
lua_pushstring(L, filenames[INFILE]);
ctrl->ref[INFILE] = lua_ref(L, 1);
lua_pushstring(L, filenames[OUTFILE]);
ctrl->ref[OUTFILE] = lua_ref(L, 1);
/* predefined file handles */
setfile(L, ctrl, stdin, INFILE);
setfile(L, ctrl, stdout, OUTFILE);
setfilebyname(L, ctrl, stdin, "_STDIN");
setfilebyname(L, ctrl, stdout, "_STDOUT");
setfilebyname(L, ctrl, stderr, "_STDERR");
/* close files when collected */
lua_pushcclosure(L, file_collect, 1); /* pops `ctrl' from stack */
lua_settagmethod(L, ctrl->iotag, "gc");
}
LUALIB_API void lua_iolibopen (lua_State *L) {
luaL_openl(L, iolib);
openwithcontrol(L);
}