xref: /netbsd-src/external/bsd/libbind/dist/bsd/mktemp.c (revision 5bbd2a12505d72a8177929a37b5cee489d0a1cfd)
1 /*	$NetBSD: mktemp.c,v 1.1.1.2 2012/09/09 16:07:43 christos Exp $	*/
2 
3 #if defined(LIBC_SCCS) && !defined(lint)
4 static const char sccsid[] = "@(#)mktemp.c	8.1 (Berkeley) 6/4/93";
5 static const char rcsid[] = "Id: mktemp.c,v 1.2 2005/04/27 04:56:11 sra Exp ";
6 #endif /* LIBC_SCCS and not lint */
7 
8 /*
9  * Copyright (c) 1987, 1993
10  *    The Regents of the University of California.  All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  * 	This product includes software developed by the University of
23  * 	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 /*
42  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
43  *
44  * Permission to use, copy, modify, and distribute this software for any
45  * purpose with or without fee is hereby granted, provided that the above
46  * copyright notice and this permission notice appear in all copies, and that
47  * the name of Digital Equipment Corporation not be used in advertising or
48  * publicity pertaining to distribution of the document or software without
49  * specific, written prior permission.
50  *
51  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
52  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
53  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
54  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
55  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
56  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
57  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
58  * SOFTWARE.
59  */
60 
61 #include "port_before.h"
62 
63 #include <sys/types.h>
64 #include <sys/stat.h>
65 
66 #include <ctype.h>
67 #include <errno.h>
68 #include <fcntl.h>
69 #include <stdio.h>
70 
71 #include "port_after.h"
72 
73 #if (!defined(NEED_MKTEMP)) && (!defined(NEED_MKSTEMP))
74 int __mktemp_unneeded__;
75 #else
76 
77 static int gettemp(char *path, int *doopen);
78 
79 #ifdef NEED_MKSTEMP
mkstemp(char * path)80 mkstemp(char *path) {
81 	int fd;
82 
83 	return (gettemp(path, &fd) ? fd : -1);
84 }
85 #endif
86 
87 #ifdef NEED_MKTEMP
88 char *
mktemp(char * path)89 mktemp(char *path) {
90 	return(gettemp(path, (int *)NULL) ? path : (char *)NULL);
91 }
92 #endif
93 
94 static int
gettemp(char * path,int * doopen)95 gettemp(char *path, int *doopen) {
96 	char *start, *trv;
97 	struct stat sbuf;
98 	u_int pid;
99 
100 	pid = getpid();
101 	for (trv = path; *trv; ++trv);		/*%< extra X's get set to 0's */
102 	while (*--trv == 'X') {
103 		*trv = (pid % 10) + '0';
104 		pid /= 10;
105 	}
106 
107 	/*
108 	 * check the target directory; if you have six X's and it
109 	 * doesn't exist this runs for a *very* long time.
110 	 */
111 	for (start = trv + 1;; --trv) {
112 		if (trv <= path)
113 			break;
114 		if (*trv == '/') {
115 			*trv = '\0';
116 			if (stat(path, &sbuf))
117 				return(0);
118 			if (!S_ISDIR(sbuf.st_mode)) {
119 				errno = ENOTDIR;
120 				return(0);
121 			}
122 			*trv = '/';
123 			break;
124 		}
125 	}
126 
127 	for (;;) {
128 		if (doopen) {
129 			if ((*doopen =
130 			    open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0)
131 				return(1);
132 			if (errno != EEXIST)
133 				return(0);
134 		}
135 		else if (stat(path, &sbuf))
136 			return(errno == ENOENT ? 1 : 0);
137 
138 		/* tricky little algorithm for backward compatibility */
139 		for (trv = start;;) {
140 			if (!*trv)
141 				return(0);
142 			if (*trv == 'z')
143 				*trv++ = 'a';
144 			else {
145 				if (isdigit(*trv))
146 					*trv = 'a';
147 				else
148 					++*trv;
149 				break;
150 			}
151 		}
152 	}
153 	/*NOTREACHED*/
154 }
155 
156 #endif /*NEED_MKTEMP*/
157 
158 /*! \file */
159