xref: /PHP-7.1/ext/zip/lib/mkstemp.c (revision 9e0cc7a1)
1 /* Adapted from NetBSB libc by Dieter Baron */
2 
3 /*	NetBSD: gettemp.c,v 1.13 2003/12/05 00:57:36 uebayasi Exp 	*/
4 
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 #include <sys/types.h>
35 #include <sys/stat.h>
36 
37 #include <assert.h>
38 #include <ctype.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #ifdef _WIN32
42 #include <io.h>
43 #endif
44 #include <stdio.h>
45 #include <stdlib.h>
46 
47 #ifndef O_BINARY
48 #define O_BINARY 0
49 #endif
50 
51 
52 int
_zip_mkstemp(char * path)53 _zip_mkstemp(char *path)
54 {
55 #ifdef _WIN32
56 	int ret;
57 	ret = _creat(_mktemp(path), _S_IREAD|_S_IWRITE);
58 	if (ret == -1) {
59 		return 0;
60 	} else {
61 		return ret;
62 	}
63 #else
64 	int fd;
65 	char *start, *trv;
66 	struct stat sbuf;
67 	pid_t pid;
68 
69 	/* To guarantee multiple calls generate unique names even if
70 	   the file is not created. 676 different possibilities with 7
71 	   or more X's, 26 with 6 or less. */
72 	static char xtra[2] = "aa";
73 	int xcnt = 0;
74 
75 	pid = getpid();
76 
77 	/* Move to end of path and count trailing X's. */
78 	for (trv = path; *trv; ++trv)
79 		if (*trv == 'X')
80 			xcnt++;
81 		else
82 			xcnt = 0;
83 
84 	/* Use at least one from xtra.  Use 2 if more than 6 X's. */
85 	if (*(trv - 1) == 'X')
86 		*--trv = xtra[0];
87 	if (xcnt > 6 && *(trv - 1) == 'X')
88 		*--trv = xtra[1];
89 
90 	/* Set remaining X's to pid digits with 0's to the left. */
91 	while (*--trv == 'X') {
92 		*trv = (pid % 10) + '0';
93 		pid /= 10;
94 	}
95 
96 	/* update xtra for next call. */
97 	if (xtra[0] != 'z')
98 		xtra[0]++;
99 	else {
100 		xtra[0] = 'a';
101 		if (xtra[1] != 'z')
102 			xtra[1]++;
103 		else
104 			xtra[1] = 'a';
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 ((fd=open(path, O_CREAT|O_EXCL|O_RDWR|O_BINARY, 0600)) >= 0)
129 			return (fd);
130 		if (errno != EEXIST)
131 			return (0);
132 
133 		/* tricky little algorithm for backward compatibility */
134 		for (trv = start;;) {
135 			if (!*trv)
136 				return (0);
137 			if (*trv == 'z')
138 				*trv++ = 'a';
139 			else {
140 				if (isdigit((unsigned char)*trv))
141 					*trv = 'a';
142 				else
143 					++*trv;
144 				break;
145 			}
146 		}
147 	}
148 	/*NOTREACHED*/
149 #endif
150 }
151