1 /* $NetBSD: opendir.c,v 1.4 2003/08/07 09:27:58 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 34 #ifdef __weak_alias 35 #define opendir _opendir 36 #endif 37 38 #include <sys/param.h> 39 #include <sys/mount.h> 40 #include <sys/stat.h> 41 42 #include <dirent.h> 43 #include <errno.h> 44 #include <fcntl.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <unistd.h> 48 49 #ifdef __weak_alias 50 __weak_alias(opendir,_opendir) 51 #endif 52 53 /* 54 * Open a directory. 55 */ 56 DIR * 57 opendir(name) 58 const char *name; 59 { 60 DIR *dirp; 61 int fd; 62 struct stat sb; 63 64 if ((fd = open(name, O_RDONLY | O_NONBLOCK)) == -1) 65 return (NULL); 66 if (fstat(fd, &sb) || !S_ISDIR(sb.st_mode)) { 67 errno = ENOTDIR; 68 close(fd); 69 return (NULL); 70 } 71 if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1 || 72 (dirp = (DIR *)malloc(sizeof(DIR))) == NULL) { 73 close(fd); 74 return (NULL); 75 } 76 77 /* 78 * Determine whether this directory is the top of a union stack. 79 * (Never is on a ramdisk) 80 */ 81 { 82 dirp->dd_len = DIRBLKSIZ; 83 dirp->dd_buf = malloc((size_t)dirp->dd_len); 84 if (dirp->dd_buf == NULL) { 85 free(dirp); 86 close (fd); 87 return (NULL); 88 } 89 dirp->dd_seek = 0; 90 } 91 92 dirp->dd_loc = 0; 93 dirp->dd_fd = fd; 94 dirp->dd_flags = DTF_HIDEW; 95 96 /* 97 * Set up seek point for rewinddir. 98 */ 99 dirp->dd_rewind = telldir(dirp); 100 101 return (dirp); 102 } 103