mktemp.c (4208B)
1 /* 2 * Copyright (c) 1987, 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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. 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 #include <fcntl.h> 37 #include <errno.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <ctype.h> 42 #include <unistd.h> 43 44 char *_mktemp(char *); 45 46 static int _gettemp(char *, int *, int, int); 47 48 static const unsigned char padchar[] = 49 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 50 51 int 52 mkstemps(path, slen) 53 char *path; 54 int slen; 55 { 56 int fd; 57 58 return (_gettemp(path, &fd, 0, slen) ? fd : -1); 59 } 60 61 int 62 mkstemp(path) 63 char *path; 64 { 65 int fd; 66 67 return (_gettemp(path, &fd, 0, 0) ? fd : -1); 68 } 69 70 char * 71 mkdtemp(path) 72 char *path; 73 { 74 return (_gettemp(path, (int *)NULL, 1, 0) ? path : (char *)NULL); 75 } 76 77 char * 78 _mktemp(path) 79 char *path; 80 { 81 return (_gettemp(path, (int *)NULL, 0, 0) ? path : (char *)NULL); 82 } 83 84 char * 85 mktemp(path) 86 char *path; 87 { 88 return (_mktemp(path)); 89 } 90 91 static int 92 _gettemp(path, doopen, domkdir, slen) 93 char *path; 94 int *doopen; 95 int domkdir; 96 int slen; 97 { 98 char *start, *trv, *suffp; 99 char *pad; 100 struct stat sbuf; 101 int rval; 102 uint32_t randx; 103 104 if (doopen != NULL && domkdir) { 105 errno = EINVAL; 106 return (0); 107 } 108 109 for (trv = path; *trv != '\0'; ++trv) 110 ; 111 trv -= slen; 112 suffp = trv; 113 --trv; 114 if (trv < path) { 115 errno = EINVAL; 116 return (0); 117 } 118 119 /* Fill space with random characters */ 120 while (trv >= path && *trv == 'X') { 121 randx = rand() % (sizeof(padchar) - 1); 122 *trv-- = padchar[randx]; 123 } 124 start = trv + 1; 125 126 /* 127 * check the target directory. 128 */ 129 if (doopen != NULL || domkdir) { 130 for (; trv > path; --trv) { 131 if (*trv == '/') { 132 *trv = '\0'; 133 rval = stat(path, &sbuf); 134 *trv = '/'; 135 if (rval != 0) 136 return (0); 137 if (!S_ISDIR(sbuf.st_mode)) { 138 errno = ENOTDIR; 139 return (0); 140 } 141 break; 142 } 143 } 144 } 145 146 for (;;) { 147 if (doopen) { 148 if ((*doopen = 149 open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0) 150 return (1); 151 if (errno != EEXIST) 152 return (0); 153 } else if (domkdir) { 154 if (mkdir(path, 0700) == 0) 155 return (1); 156 if (errno != EEXIST) 157 return (0); 158 } else if (lstat(path, &sbuf)) 159 return (errno == ENOENT); 160 161 /* If we have a collision, cycle through the space of filenames */ 162 for (trv = start;;) { 163 if (*trv == '\0' || trv == suffp) 164 return (0); 165 pad = strchr(padchar, *trv); 166 if (pad == NULL || *++pad == '\0') 167 *trv++ = padchar[0]; 168 else { 169 *trv++ = *pad; 170 break; 171 } 172 } 173 } 174 /*NOTREACHED*/ 175 }