xref: /illumos-gate/usr/src/lib/libc/port/stdio/tmpnam_r.c (revision eb0cc229f19c437a6b538d3ac0d0443268290b7e)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*	Copyright (c) 1988 AT&T */
30 /*	  All Rights Reserved	*/
31 
32 
33 #pragma weak tmpnam = _tmpnam
34 #pragma weak tmpnam_r = _tmpnam_r
35 
36 #include "synonyms.h"
37 #include "mtlib.h"
38 #include <sys/types.h>
39 #include <stdio.h>
40 #include <string.h>
41 #include <stdlib.h>
42 #include <errno.h>
43 #include <thread.h>
44 #include <synch.h>
45 #include "tsd.h"
46 
47 static char seed[] = { 'a', 'a', 'a', '\0' };
48 
49 static mutex_t seed_lk = DEFAULTMUTEX;
50 
51 char *
52 tmpnam_r(char *s)
53 {
54 	char *p = s, *q;
55 
56 	if (!s)
57 		return (NULL);
58 
59 	(void) strcpy(p, P_tmpdir);
60 	lmutex_lock(&seed_lk);
61 	(void) strcat(p, seed);
62 	(void) strcat(p, "XXXXXX");
63 
64 	q = seed;
65 	while (*q == 'z')
66 		*q++ = 'a';
67 	if (*q != '\0')
68 		++*q;
69 	lmutex_unlock(&seed_lk);
70 	(void) mktemp(p);
71 	return (p);
72 }
73 
74 char *
75 tmpnam(char *s)
76 {
77 	if (s == NULL)
78 		s = tsdalloc(_T_TMPNAM, L_tmpnam, NULL);
79 	return (tmpnam_r(s));
80 }
81