1 /* -*- mode: c; c-file-style: "bsd"; indent-tabs-mode: t -*- */ 2 /* 3 * Copyright (c) 1987, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the University of 17 * California, Berkeley and its contributors. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #if defined(LIBC_SCCS) && !defined(lint) 36 static char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93"; 37 #endif /* LIBC_SCCS and not lint */ 38 39 #include "k5-platform.h" 40 41 #include <sys/types.h> 42 #include <sys/stat.h> 43 #include <fcntl.h> 44 #include <errno.h> 45 #include <stdio.h> 46 #include <ctype.h> 47 #ifdef HAVE_UNISTD_H 48 #include <unistd.h> 49 #endif 50 51 #ifndef O_BINARY 52 #define O_BINARY 0 53 #endif 54 55 #if !defined S_ISDIR 56 #if defined S_IFMT 57 #define S_ISDIR(MODE) (((MODE) & S_IFMT) == S_IFDIR) 58 #elif defined _S_IFMT 59 #define S_ISDIR(MODE) (((MODE) & _S_IFMT) == _S_IFDIR) 60 #else 61 /* Hope that there's a S_ISDIR function defined. */ 62 #endif 63 #endif 64 65 static int _gettemp(char *, int *); 66 67 int mkstemp(path) 68 char *path; 69 { 70 int fd; 71 72 return (_gettemp(path, &fd) ? fd : -1); 73 } 74 75 static int 76 _gettemp(path, doopen) 77 char *path; 78 int *doopen; 79 { 80 char *start, *trv; 81 struct stat sbuf; 82 u_int pid; 83 84 pid = getpid(); 85 for (trv = path; *trv; ++trv); /* extra X's get set to 0's */ 86 while (*--trv == 'X') { 87 *trv = (pid % 10) + '0'; 88 pid /= 10; 89 } 90 91 /* 92 * check the target directory; if you have six X's and it 93 * doesn't exist this runs for a *very* long time. 94 */ 95 for (start = trv + 1;; --trv) { 96 if (trv <= path) 97 break; 98 if (*trv == '/') { 99 *trv = '\0'; 100 if (stat(path, &sbuf)) 101 return(0); 102 if (!S_ISDIR(sbuf.st_mode)) { 103 errno = ENOTDIR; 104 return(0); 105 } 106 *trv = '/'; 107 break; 108 } 109 } 110 111 for (;;) { 112 if (doopen) { 113 if ((*doopen = 114 open(path, O_CREAT|O_EXCL|O_RDWR|O_BINARY, 0600)) >= 0) 115 return(1); 116 if (errno != EEXIST) 117 return(0); 118 } 119 else if (stat(path, &sbuf)) 120 return(errno == ENOENT ? 1 : 0); 121 122 /* tricky little algorithm for backward compatibility */ 123 for (trv = start;;) { 124 if (!*trv) 125 return(0); 126 if (*trv == 'z') 127 *trv++ = 'a'; 128 else { 129 if (isdigit(*trv)) 130 *trv = 'a'; 131 else 132 ++*trv; 133 break; 134 } 135 } 136 } 137 /*NOTREACHED*/ 138 } 139