1/* THIS FILE HAS BEEN MODIFIED FROM THE ORIGINAL OPENBSD SOURCE */
2/* Changes: Removed mktemp */
3
4/*	$OpenBSD: mktemp.c,v 1.19 2005/08/08 08:05:36 espie Exp $ */
5/*
6 * Copyright (c) 1987, 1993
7 *	The Regents of the University of California.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/* OPENBSD ORIGINAL: lib/libc/stdio/mktemp.c */
35
36#include "includes.h"
37
38#include <sys/types.h>
39#include <sys/stat.h>
40
41#include <fcntl.h>
42#include <ctype.h>
43#include <errno.h>
44#include <unistd.h>
45
46#if !defined(HAVE_MKDTEMP) || defined(HAVE_STRICT_MKSTEMP)
47
48static int _gettemp(char *, int *, int, int);
49
50int
51mkstemps(char *path, int slen)
52{
53	int fd;
54
55	return (_gettemp(path, &fd, 0, slen) ? fd : -1);
56}
57
58int
59mkstemp(char *path)
60{
61	int fd;
62
63	return (_gettemp(path, &fd, 0, 0) ? fd : -1);
64}
65
66char *
67mkdtemp(char *path)
68{
69	return(_gettemp(path, (int *)NULL, 1, 0) ? path : (char *)NULL);
70}
71
72static int
73_gettemp(path, doopen, domkdir, slen)
74	char *path;
75	register int *doopen;
76	int domkdir;
77	int slen;
78{
79	register char *start, *trv, *suffp;
80	struct stat sbuf;
81	int rval;
82	pid_t pid;
83
84	if (doopen && domkdir) {
85		errno = EINVAL;
86		return(0);
87	}
88
89	for (trv = path; *trv; ++trv)
90		;
91	trv -= slen;
92	suffp = trv;
93	--trv;
94	if (trv < path) {
95		errno = EINVAL;
96		return (0);
97	}
98	pid = getpid();
99	while (trv >= path && *trv == 'X' && pid != 0) {
100		*trv-- = (pid % 10) + '0';
101		pid /= 10;
102	}
103	while (trv >= path && *trv == 'X') {
104		char c;
105
106		pid = (arc4random() & 0xffff) % (26+26);
107		if (pid < 26)
108			c = pid + 'A';
109		else
110			c = (pid - 26) + 'a';
111		*trv-- = c;
112	}
113	start = trv + 1;
114
115	/*
116	 * check the target directory; if you have six X's and it
117	 * doesn't exist this runs for a *very* long time.
118	 */
119	if (doopen || domkdir) {
120		for (;; --trv) {
121			if (trv <= path)
122				break;
123			if (*trv == '/') {
124				*trv = '\0';
125				rval = stat(path, &sbuf);
126				*trv = '/';
127				if (rval != 0)
128					return(0);
129				if (!S_ISDIR(sbuf.st_mode)) {
130					errno = ENOTDIR;
131					return(0);
132				}
133				break;
134			}
135		}
136	}
137
138	for (;;) {
139		if (doopen) {
140			if ((*doopen =
141			    open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0)
142				return(1);
143			if (errno != EEXIST)
144				return(0);
145		} else if (domkdir) {
146			if (mkdir(path, 0700) == 0)
147				return(1);
148			if (errno != EEXIST)
149				return(0);
150		} else if (lstat(path, &sbuf))
151			return(errno == ENOENT ? 1 : 0);
152
153		/* tricky little algorithm for backward compatibility */
154		for (trv = start;;) {
155			if (!*trv)
156				return (0);
157			if (*trv == 'Z') {
158				if (trv == suffp)
159					return (0);
160				*trv++ = 'a';
161			} else {
162				if (isdigit(*trv))
163					*trv = 'a';
164				else if (*trv == 'z')	/* inc from z to A */
165					*trv = 'A';
166				else {
167					if (trv == suffp)
168						return (0);
169					++*trv;
170				}
171				break;
172			}
173		}
174	}
175	/*NOTREACHED*/
176}
177
178#endif /* !defined(HAVE_MKDTEMP) || defined(HAVE_STRICT_MKSTEMP) */
179