OpenBSD-4.6/usr.bin/sort/tmp.c

/*	$OpenBSD: tmp.c,v 1.8 2008/03/19 19:25:49 kili Exp $	*/

/*-
 * Copyright (c) 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Peter McIlroy.
 *
 * 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. 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.
 */

#ifndef lint
#if 0
static char sccsid[] = "@(#)tmp.c	8.1 (Berkeley) 6/6/93";
#else
static char rcsid[] = "$OpenBSD: tmp.c,v 1.8 2008/03/19 19:25:49 kili Exp $";
#endif
#endif /* not lint */

#include <sys/param.h>

#include <err.h>
#include <errno.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "sort.h"
#include "pathnames.h"

#define _NAME_TMP "sort.XXXXXXXXXX"

FILE *
ftmp(void)
{
	sigset_t set, oset;
	FILE *fp;
	int fd;
	char path[PATH_MAX];

	if (tmpdir[0] == '\0')
		errx(2, "invalid temporary directory: \"\"");
	(void)snprintf(path, sizeof(path), "%s%s%s", tmpdir,
		       (tmpdir[strlen(tmpdir)-1] != '/') ? "/" : "", _NAME_TMP);

	sigfillset(&set);
	(void)sigprocmask(SIG_BLOCK, &set, &oset);
	if ((fd = mkstemp(path)) < 0)
		err(2, "%s", path);
	if (!(fp = fdopen(fd, "w+")))
		err(2, "%s", path);
	(void)unlink(path);

	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
	return (fp);
}