xref: /netbsd-src/lib/libc/stdio/tmpfile.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: tmpfile.c,v 1.6 1997/07/13 20:15:31 christos Exp $	*/
2 
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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #if defined(LIBC_SCCS) && !defined(lint)
41 #if 0
42 static char sccsid[] = "@(#)tmpfile.c	8.1 (Berkeley) 6/4/93";
43 #else
44 __RCSID("$NetBSD: tmpfile.c,v 1.6 1997/07/13 20:15:31 christos Exp $");
45 #endif
46 #endif /* LIBC_SCCS and not lint */
47 
48 #include <sys/types.h>
49 #include <unistd.h>
50 #include <signal.h>
51 #include <errno.h>
52 #include <stdio.h>
53 #include <string.h>
54 #include <paths.h>
55 
56 FILE *
57 tmpfile()
58 {
59 	sigset_t set, oset;
60 	FILE *fp;
61 	int fd, sverrno;
62 #define	TRAILER	"tmp.XXXXXX"
63 	char buf[sizeof(_PATH_TMP) + sizeof(TRAILER)];
64 
65 	(void)memcpy(buf, _PATH_TMP, sizeof(_PATH_TMP) - 1);
66 	(void)memcpy(buf + sizeof(_PATH_TMP) - 1, TRAILER, sizeof(TRAILER));
67 
68 	sigfillset(&set);
69 	(void)sigprocmask(SIG_BLOCK, &set, &oset);
70 
71 	fd = mkstemp(buf);
72 	if (fd != -1)
73 		(void)unlink(buf);
74 
75 	(void)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