xref: /dragonfly/lib/libc/stdio/tempnam.c (revision 25a2db75)
1 /*
2  * Copyright (c) 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)tempnam.c	8.1 (Berkeley) 6/4/93
30  * $FreeBSD: src/lib/libc/stdio/tempnam.c,v 1.11 2007/01/09 00:28:07 imp Exp $
31  * $DragonFly: src/lib/libc/stdio/tempnam.c,v 1.5 2005/11/20 11:07:30 swildner Exp $
32  */
33 
34 #include <sys/param.h>
35 #include <errno.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <paths.h>
41 
42 __warn_references(tempnam,
43     "warning: tempnam() possibly used unsafely; consider using mkstemp()");
44 
45 extern char *_mktemp(char *);
46 
47 char *
48 tempnam(const char *dir, const char *pfx)
49 {
50 	int sverrno;
51 	char *f, *name;
52 
53 	if (!(name = malloc(MAXPATHLEN)))
54 		return(NULL);
55 
56 	if (!pfx)
57 		pfx = "tmp.";
58 
59 	if (issetugid() == 0 && (f = getenv("TMPDIR"))) {
60 		snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
61 		    *(f + strlen(f) - 1) == '/'? "": "/", pfx);
62 		if ((f = _mktemp(name)))
63 			return(f);
64 	}
65 
66 	if ((f = (char *)dir)) {
67 		snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
68 		    *(f + strlen(f) - 1) == '/'? "": "/", pfx);
69 		if ((f = _mktemp(name)))
70 			return(f);
71 	}
72 
73 	f = P_tmpdir;
74 	snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
75 	if ((f = _mktemp(name)))
76 		return(f);
77 
78 	f = _PATH_TMP;
79 	snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
80 	if ((f = _mktemp(name)))
81 		return(f);
82 
83 	sverrno = errno;
84 	free(name);
85 	errno = sverrno;
86 	return(NULL);
87 }
88