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 "config.h" 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 static const char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93"; 38 #endif /* LIBC_SCCS and not lint */ 39 40 #include <sys/types.h> 41 #include <sys/stat.h> 42 #include <fcntl.h> 43 #include <errno.h> 44 #include <stdio.h> 45 #include <ctype.h> 46 47 static int _gettemp(char *path, register int *doopen); 48 49 /* 50 * PUBLIC: #ifndef HAVE_MKSTEMP 51 * PUBLIC: int mkstemp __P((char *)); 52 * PUBLIC: #endif 53 */ 54 mkstemp(char *path) 55 { 56 int fd; 57 58 return (_gettemp(path, &fd) ? fd : -1); 59 } 60 61 char * 62 mktemp(char *path) 63 { 64 return(_gettemp(path, (int *)NULL) ? path : (char *)NULL); 65 } 66 67 static 68 _gettemp(char *path, register int *doopen) 69 { 70 extern int errno; 71 register char *start, *trv; 72 struct stat sbuf; 73 u_int pid; 74 75 pid = getpid(); 76 for (trv = path; *trv; ++trv); /* extra X's get set to 0's */ 77 while (*--trv == 'X') { 78 *trv = (pid % 10) + '0'; 79 pid /= 10; 80 } 81 82 /* 83 * check the target directory; if you have six X's and it 84 * doesn't exist this runs for a *very* long time. 85 */ 86 for (start = trv + 1;; --trv) { 87 if (trv <= path) 88 break; 89 if (*trv == '/') { 90 *trv = '\0'; 91 if (stat(path, &sbuf)) 92 return(0); 93 if (!S_ISDIR(sbuf.st_mode)) { 94 errno = ENOTDIR; 95 return(0); 96 } 97 *trv = '/'; 98 break; 99 } 100 } 101 102 for (;;) { 103 if (doopen) { 104 if ((*doopen = 105 open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0) 106 return(1); 107 if (errno != EEXIST) 108 return(0); 109 } 110 else if (stat(path, &sbuf)) 111 return(errno == ENOENT ? 1 : 0); 112 113 /* tricky little algorithm for backward compatibility */ 114 for (trv = start;;) { 115 if (!*trv) 116 return(0); 117 if (*trv == 'z') 118 *trv++ = 'a'; 119 else { 120 if (isdigit(*trv)) 121 *trv = 'a'; 122 else 123 ++*trv; 124 break; 125 } 126 } 127 } 128 /*NOTREACHED*/ 129 } 130