1 /* $NetBSD: tempnam.c,v 1.22 2012/03/15 18:22:30 christos 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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)tempnam.c 8.1 (Berkeley) 6/4/93";
36 #else
37 __RCSID("$NetBSD: tempnam.c,v 1.22 2012/03/15 18:22:30 christos Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40
41 #include "namespace.h"
42 #include <sys/param.h>
43 #include <errno.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 #include <paths.h>
49 #include "reentrant.h"
50 #include "local.h"
51
52 __warn_references(tempnam,
53 "warning: tempnam() possibly used unsafely, use mkstemp() or mkdtemp()")
54
55 static const char *
trailsl(const char * f)56 trailsl(const char *f)
57 {
58 const char *s = f;
59 while (*s)
60 s++;
61 return (f != s && s[-1] == '/') ? "" : "/";
62 }
63
64 static char *
gentemp(char * name,size_t len,const char * tmp,const char * pfx)65 gentemp(char *name, size_t len, const char *tmp, const char *pfx)
66 {
67 (void)snprintf(name, len, "%s%s%sXXXXXXXXXX", tmp, trailsl(tmp), pfx);
68 return _mktemp(name);
69 }
70
71 char *
tempnam(const char * dir,const char * pfx)72 tempnam(const char *dir, const char *pfx)
73 {
74 int sverrno;
75 char *name, *f;
76 const char *tmp;
77
78 if (!(name = malloc((size_t)MAXPATHLEN)))
79 return NULL;
80
81 if (!pfx)
82 pfx = "tmp.";
83
84 if ((tmp = getenv("TMPDIR")) != NULL &&
85 (f = gentemp(name, (size_t)MAXPATHLEN, tmp, pfx)) != NULL)
86 return f;
87
88 if (dir != NULL &&
89 (f = gentemp(name, (size_t)MAXPATHLEN, dir, pfx)) != NULL)
90 return f;
91
92 if ((f = gentemp(name, (size_t)MAXPATHLEN, P_tmpdir, pfx)) != NULL)
93 return f;
94
95 if ((f = gentemp(name, (size_t)MAXPATHLEN, _PATH_TMP, pfx)) != NULL)
96 return f;
97
98 sverrno = errno;
99 free(name);
100 errno = sverrno;
101 return NULL;
102 }
103