/*- * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Chris Torek. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if defined(LIBC_SCCS) && !defined(lint)static char rcsid[] = "$OpenBSD: freopen.c,v 1.3 1996/08/19 08:32:45 tholo Exp $";#endif /* LIBC_SCCS and not lint */ #include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <errno.h>#include <unistd.h>#include <stdio.h>#include <stdlib.h>#include "local.h" /* * Re-direct an existing, open (probably) file to some other file. * ANSI is written such that the original file gets closed if at * all possible, no matter what. */FILE *freopen(file, mode, fp) const char *file, *mode; register FILE *fp;{ register int f; int flags, isopen, oflags, sverrno, wantfd; if ((flags = __sflags(mode, &oflags)) == 0) { (void) fclose(fp); return (NULL); } if (!__sdidinit) __sinit(); /* * There are actually programs that depend on being able to "freopen" * descriptors that weren't originally open. Keep this from breaking. * Remember whether the stream was open to begin with, and which file * descriptor (if any) was associated with it. If it was attached to * a descriptor, defer closing it; freopen("/dev/stdin", "r", stdin) * should work. This is unnecessary if it was not a Unix file. */ if (fp->_flags == 0) { fp->_flags = __SEOF; /* hold on to it */ isopen = 0; wantfd = -1; } else { /* flush the stream; ANSI doesn't require this. */ if (fp->_flags & __SWR) (void) __sflush(fp); /* if close is NULL, closing is a no-op, hence pointless */ isopen = fp->_close != NULL; if ((wantfd = fp->_file) < 0 && isopen) { (void) (*fp->_close)(fp->_cookie); isopen = 0; } } /* Get a new descriptor to refer to the new file. */ f = open(file, oflags, DEFFILEMODE); if (f < 0 && isopen) { /* If out of fd's close the old one and try again. */ if (errno == ENFILE || errno == EMFILE) { (void) (*fp->_close)(fp->_cookie); isopen = 0; f = open(file, oflags, DEFFILEMODE); } } sverrno = errno; /* * Finish closing fp. Even if the open succeeded above, we cannot * keep fp->_base: it may be the wrong size. This loses the effect * of any setbuffer calls, but stdio has always done this before. */ if (isopen && f != wantfd) (void) (*fp->_close)(fp->_cookie); if (fp->_flags & __SMBF) free((char *)fp->_bf._base); fp->_w = 0; fp->_r = 0; fp->_p = NULL; fp->_bf._base = NULL; fp->_bf._size = 0; fp->_lbfsize = 0; if (HASUB(fp)) FREEUB(fp); fp->_ub._size = 0; if (HASLB(fp)) FREELB(fp); fp->_lb._size = 0; if (f < 0) { /* did not get it after all */ fp->_flags = 0; /* set it free */ errno = sverrno; /* restore in case _close clobbered */ return (NULL); } /* * If reopening something that was open before on a real file, try * to maintain the descriptor. Various C library routines (perror) * assume stderr is always fd STDERR_FILENO, even if being freopen'd. */ if (wantfd >= 0 && f != wantfd) { if (dup2(f, wantfd) >= 0) { (void) close(f); f = wantfd; } } fp->_flags = flags; fp->_file = f; fp->_cookie = fp; fp->_read = __sread; fp->_write = __swrite; fp->_seek = __sseek; fp->_close = __sclose; return (fp);}
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char rcsid[] = "$OpenBSD: freopen.c,v 1.3 1996/08/19 08:32:45 tholo Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include "local.h"
/*
* Re-direct an existing, open (probably) file to some other file.
* ANSI is written such that the original file gets closed if at
* all possible, no matter what.
*/
FILE *
freopen(file, mode, fp)
const char *file, *mode;
register FILE *fp;
{
register int f;
int flags, isopen, oflags, sverrno, wantfd;
if ((flags = __sflags(mode, &oflags)) == 0) {
(void) fclose(fp);
return (NULL);
}
if (!__sdidinit)
__sinit();
/*
* There are actually programs that depend on being able to "freopen"
* descriptors that weren't originally open. Keep this from breaking.
* Remember whether the stream was open to begin with, and which file
* descriptor (if any) was associated with it. If it was attached to
* a descriptor, defer closing it; freopen("/dev/stdin", "r", stdin)
* should work. This is unnecessary if it was not a Unix file.
*/
if (fp->_flags == 0) {
fp->_flags = __SEOF; /* hold on to it */
isopen = 0;
wantfd = -1;
} else {
/* flush the stream; ANSI doesn't require this. */
if (fp->_flags & __SWR)
(void) __sflush(fp);
/* if close is NULL, closing is a no-op, hence pointless */
isopen = fp->_close != NULL;
if ((wantfd = fp->_file) < 0 && isopen) {
(void) (*fp->_close)(fp->_cookie);
isopen = 0;
}
}
/* Get a new descriptor to refer to the new file. */
f = open(file, oflags, DEFFILEMODE);
if (f < 0 && isopen) {
/* If out of fd's close the old one and try again. */
if (errno == ENFILE || errno == EMFILE) {
(void) (*fp->_close)(fp->_cookie);
isopen = 0;
f = open(file, oflags, DEFFILEMODE);
}
}
sverrno = errno;
/*
* Finish closing fp. Even if the open succeeded above, we cannot
* keep fp->_base: it may be the wrong size. This loses the effect
* of any setbuffer calls, but stdio has always done this before.
*/
if (isopen && f != wantfd)
(void) (*fp->_close)(fp->_cookie);
if (fp->_flags & __SMBF)
free((char *)fp->_bf._base);
fp->_w = 0;
fp->_r = 0;
fp->_p = NULL;
fp->_bf._base = NULL;
fp->_bf._size = 0;
fp->_lbfsize = 0;
if (HASUB(fp))
FREEUB(fp);
fp->_ub._size = 0;
if (HASLB(fp))
FREELB(fp);
fp->_lb._size = 0;
if (f < 0) { /* did not get it after all */
fp->_flags = 0; /* set it free */
errno = sverrno; /* restore in case _close clobbered */
return (NULL);
}
/*
* If reopening something that was open before on a real file, try
* to maintain the descriptor. Various C library routines (perror)
* assume stderr is always fd STDERR_FILENO, even if being freopen'd.
*/
if (wantfd >= 0 && f != wantfd) {
if (dup2(f, wantfd) >= 0) {
(void) close(f);
f = wantfd;
}
}
fp->_flags = flags;
fp->_file = f;
fp->_cookie = fp;
fp->_read = __sread;
fp->_write = __swrite;
fp->_seek = __sseek;
fp->_close = __sclose;
return (fp);
}