1 /* $Id: compat_mkdtemp.c,v 1.4 2021/09/19 15:02:55 schwarze Exp $ */ 2 /* 3 * Copyright (c) 2015, 2021 Ingo Schwarze <schwarze@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 * 17 * The algorithm of this function is inspired by OpenBSD mkdtemp(3) 18 * by Theo de Raadt and Todd Miller, but the code differs. 19 */ 20 #include "config.h" 21 22 #include <sys/stat.h> 23 #include <errno.h> 24 #include <limits.h> 25 #include <stdlib.h> 26 #include <string.h> 27 28 char * 29 mkdtemp(char *path) 30 { 31 char *start, *cp; 32 unsigned int tries; 33 34 start = strchr(path, '\0'); 35 while (start > path && start[-1] == 'X') 36 start--; 37 38 for (tries = INT_MAX; tries; tries--) { 39 if (mktemp(path) == NULL) 40 return NULL; 41 if (mkdir(path, S_IRUSR | S_IWUSR | S_IXUSR) == 0) 42 return path; 43 for (cp = start; *cp != '\0'; cp++) 44 *cp = 'X'; 45 if (errno != EEXIST) 46 return NULL; 47 } 48 errno = EEXIST; 49 return NULL; 50 } 51