xref: /netbsd-src/lib/libc/stdio/tempnam.c (revision 1ffa7b76c40339c17a0fb2a09fac93f287cfc046)
1 /*	$NetBSD: tempnam.c,v 1.16 2003/01/18 11:29:58 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)tempnam.c	8.1 (Berkeley) 6/4/93";
40 #else
41 __RCSID("$NetBSD: tempnam.c,v 1.16 2003/01/18 11:29:58 thorpej Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 #include "namespace.h"
46 #include <sys/param.h>
47 #include <errno.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <paths.h>
53 #include "reentrant.h"
54 #include "local.h"
55 
56 __warn_references(tempnam,
57     "warning: tempnam() possibly used unsafely, use mkstemp() or mkdtemp()")
58 
59 char *
60 tempnam(dir, pfx)
61 	const char *dir, *pfx;
62 {
63 	int sverrno;
64 	char *f, *name;
65 
66 	if (!(name = malloc((size_t)MAXPATHLEN)))
67 		return(NULL);
68 
69 	if (!pfx)
70 		pfx = "tmp.";
71 
72 	if ((f = getenv("TMPDIR")) != NULL) {
73 		(void)snprintf(name, (size_t)MAXPATHLEN, "%s%s%sXXXXXXXXXX", f,
74 		    *(f + strlen(f) - 1) == '/'? "": "/", pfx);
75 		if ((f = _mktemp(name)) != NULL)
76 			return(f);
77 	}
78 
79 	if ((/* LINTED */f = (char *)dir) != NULL) {
80 		(void)snprintf(name, (size_t)MAXPATHLEN, "%s%s%sXXXXXXXXXX", f,
81 		    *(f + strlen(f) - 1) == '/'? "": "/", pfx);
82 		if ((f = _mktemp(name)) != NULL)
83 			return(f);
84 	}
85 
86 	f = P_tmpdir;
87 	(void)snprintf(name, (size_t)MAXPATHLEN, "%s%sXXXXXXXXXX", f, pfx);
88 	if ((f = _mktemp(name)) != NULL)
89 		return(f);
90 
91 	f = _PATH_TMP;
92 	(void)snprintf(name, (size_t)MAXPATHLEN, "%s%sXXXXXXXXXX", f, pfx);
93 	if ((f = _mktemp(name)) != NULL)
94 		return(f);
95 
96 	sverrno = errno;
97 	free(name);
98 	errno = sverrno;
99 	return(NULL);
100 }
101