1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include "namespace.h"
36#include <sys/types.h>
37#include <signal.h>
38#include <unistd.h>
39#include <errno.h>
40#include <stdio.h>
41#include <stdlib.h>
42#include <string.h>
43#include <paths.h>
44#include "un-namespace.h"
45#include "libc_private.h"
46
47FILE *
48tmpfile(void)
49{
50	sigset_t set, oset;
51	FILE *fp;
52	int fd, sverrno;
53#define	TRAILER	"tmp.XXXXXX"
54	char *buf;
55	const char *tmpdir;
56
57	tmpdir = secure_getenv("TMPDIR");
58	if (tmpdir == NULL)
59		tmpdir = _PATH_TMP;
60
61	(void)asprintf(&buf, "%s%s%s", tmpdir,
62	    (tmpdir[strlen(tmpdir) - 1] == '/') ? "" : "/", TRAILER);
63	if (buf == NULL)
64		return (NULL);
65
66	sigfillset(&set);
67	(void)__libc_sigprocmask(SIG_BLOCK, &set, &oset);
68
69	fd = mkstemp(buf);
70	if (fd != -1)
71		(void)unlink(buf);
72
73	free(buf);
74
75	(void)__libc_sigprocmask(SIG_SETMASK, &oset, NULL);
76
77	if (fd == -1)
78		return (NULL);
79
80	if ((fp = fdopen(fd, "w+")) == NULL) {
81		sverrno = errno;
82		(void)_close(fd);
83		errno = sverrno;
84		return (NULL);
85	}
86	return (fp);
87}
88