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 #if defined(LIBC_SCCS) && !defined(lint)
36 static char sccsid[] = "@(#)tmpfile.c 8.1 (Berkeley) 6/4/93";
37 #endif /* LIBC_SCCS and not lint */
38 #include "namespace.h"
39 #include <sys/types.h>
40 #include <signal.h>
41 #include <unistd.h>
42 #include <errno.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <paths.h>
47 #include "un-namespace.h"
48 #include "libc_private.h"
49
50 FILE *
tmpfile(void)51 tmpfile(void)
52 {
53 sigset_t set, oset;
54 FILE *fp;
55 int fd, sverrno;
56 #define TRAILER "tmp.XXXXXX"
57 char *buf;
58 const char *tmpdir;
59
60 tmpdir = secure_getenv("TMPDIR");
61 if (tmpdir == NULL)
62 tmpdir = _PATH_TMP;
63
64 (void)asprintf(&buf, "%s%s%s", tmpdir,
65 (tmpdir[strlen(tmpdir) - 1] == '/') ? "" : "/", TRAILER);
66 if (buf == NULL)
67 return (NULL);
68
69 sigfillset(&set);
70 (void)__libc_sigprocmask(SIG_BLOCK, &set, &oset);
71
72 fd = mkstemp(buf);
73 if (fd != -1)
74 (void)unlink(buf);
75
76 free(buf);
77
78 (void)__libc_sigprocmask(SIG_SETMASK, &oset, NULL);
79
80 if (fd == -1)
81 return (NULL);
82
83 if ((fp = fdopen(fd, "w+")) == NULL) {
84 sverrno = errno;
85 (void)_close(fd);
86 errno = sverrno;
87 return (NULL);
88 }
89 return (fp);
90 }
91