1/*	$OpenBSD: tmpfile.c,v 1.10 2005/10/10 12:00:52 espie Exp $ */
2/*-
3 * Copyright (c) 1990, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Chris Torek.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <sys/types.h>
35#include <sys/stat.h>
36#include <unistd.h>
37#include <signal.h>
38#include <errno.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42#include <paths.h>
43
44FILE *
45tmpfile(void)
46{
47	sigset_t set, oset;
48	FILE *fp;
49	int fd, sverrno;
50#define	TRAILER	"tmp.XXXXXXXXXX"
51	char buf[sizeof(_PATH_TMP) + sizeof(TRAILER)];
52
53	(void)memcpy(buf, _PATH_TMP, sizeof(_PATH_TMP) - 1);
54	(void)memcpy(buf + sizeof(_PATH_TMP) - 1, TRAILER, sizeof(TRAILER));
55
56	sigfillset(&set);
57	(void)sigprocmask(SIG_BLOCK, &set, &oset);
58
59	fd = mkstemp(buf);
60	if (fd != -1) {
61		mode_t u;
62
63		(void)unlink(buf);
64		u = umask(0);
65		(void)umask(u);
66		(void)fchmod(fd, 0666 & ~u);
67	}
68
69	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
70
71	if (fd == -1)
72		return (NULL);
73
74	if ((fp = fdopen(fd, "w+")) == NULL) {
75		sverrno = errno;
76		(void)close(fd);
77		errno = sverrno;
78		return (NULL);
79	}
80	return (fp);
81}
82