tempnam.c revision 331722 
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 * 3. 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
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)tempnam.c	8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: stable/11/lib/libc/stdio/tempnam.c 331722 2018-03-29 02:50:57Z eadler $");
35
36#include <sys/param.h>
37#include <errno.h>
38#include <stdio.h>
39#include <stdlib.h>
40#include <string.h>
41#include <unistd.h>
42#include <paths.h>
43
44__warn_references(tempnam,
45    "warning: tempnam() possibly used unsafely; consider using mkstemp()");
46
47extern char *_mktemp(char *);
48
49char *
50tempnam(const char *dir, const char *pfx)
51{
52	int sverrno;
53	char *f, *name;
54
55	if (!(name = malloc(MAXPATHLEN)))
56		return(NULL);
57
58	if (!pfx)
59		pfx = "tmp.";
60
61	if (issetugid() == 0 && (f = getenv("TMPDIR"))) {
62		(void)snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
63		    *(f + strlen(f) - 1) == '/'? "": "/", pfx);
64		if ((f = _mktemp(name)))
65			return(f);
66	}
67
68	if ((f = (char *)dir)) {
69		(void)snprintf(name, MAXPATHLEN, "%s%s%sXXXXXX", f,
70		    *(f + strlen(f) - 1) == '/'? "": "/", pfx);
71		if ((f = _mktemp(name)))
72			return(f);
73	}
74
75	f = P_tmpdir;
76	(void)snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
77	if ((f = _mktemp(name)))
78		return(f);
79
80	f = _PATH_TMP;
81	(void)snprintf(name, MAXPATHLEN, "%s%sXXXXXX", f, pfx);
82	if ((f = _mktemp(name)))
83		return(f);
84
85	sverrno = errno;
86	free(name);
87	errno = sverrno;
88	return(NULL);
89}
90