1 /* $NetBSD: opendir.c,v 1.37 2010/09/26 02:26:59 yamt 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 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)opendir.c 8.7 (Berkeley) 12/10/94"; 36 #else 37 __RCSID("$NetBSD: opendir.c,v 1.37 2010/09/26 02:26:59 yamt Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include "reentrant.h" 43 #include "extern.h" 44 45 #include <sys/param.h> 46 #include <sys/mount.h> 47 #include <sys/stat.h> 48 49 #include <assert.h> 50 #include <dirent.h> 51 #include <errno.h> 52 #include <fcntl.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <unistd.h> 56 57 #include "dirent_private.h" 58 59 static DIR *__opendir_common(int, const char *, int); 60 61 __weak_alias(fdopendir,_fdopendir) 62 63 /* 64 * Open a directory. 65 */ 66 DIR * 67 opendir(const char *name) 68 { 69 70 _DIAGASSERT(name != NULL); 71 72 return (__opendir2(name, DTF_HIDEW|DTF_NODUP)); 73 } 74 75 DIR * 76 __opendir2(const char *name, int flags) 77 { 78 int fd; 79 80 if ((fd = open(name, O_RDONLY | O_NONBLOCK)) == -1) 81 return NULL; 82 return __opendir_common(fd, name, flags); 83 } 84 85 #ifndef __LIBC12_SOURCE__ 86 DIR * 87 _fdopendir(int fd) 88 { 89 90 return __opendir_common(fd, NULL, DTF_HIDEW|DTF_NODUP); 91 } 92 #endif 93 94 static DIR * 95 __opendir_common(int fd, const char *name, int flags) 96 { 97 DIR *dirp = NULL; 98 int serrno; 99 struct stat sb; 100 struct statvfs sfb; 101 int error; 102 103 if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) 104 goto error; 105 if (fstat(fd, &sb) || !S_ISDIR(sb.st_mode)) { 106 errno = ENOTDIR; 107 goto error; 108 } 109 if ((dirp = (DIR *)malloc(sizeof(DIR))) == NULL) 110 goto error; 111 dirp->dd_buf = NULL; 112 dirp->dd_internal = NULL; 113 #ifdef _REENTRANT 114 if (__isthreaded) { 115 if ((dirp->dd_lock = malloc(sizeof(mutex_t))) == NULL) 116 goto error; 117 mutex_init((mutex_t *)dirp->dd_lock, NULL); 118 } 119 #endif 120 121 /* 122 * Tweak flags for the underlying filesystem. 123 */ 124 125 if (fstatvfs1(fd, &sfb, ST_NOWAIT) < 0) 126 goto error; 127 if ((flags & DTF_NODUP) != 0) { 128 if (!strncmp(sfb.f_fstypename, MOUNT_UNION, 129 sizeof(sfb.f_fstypename)) || 130 (sfb.f_flag & MNT_UNION) != 0) { 131 flags |= __DTF_READALL; 132 } else { 133 flags &= ~DTF_NODUP; 134 } 135 } 136 if (!strncmp(sfb.f_fstypename, MOUNT_NFS, sizeof(sfb.f_fstypename))) { 137 flags |= __DTF_READALL | __DTF_RETRY_ON_BADCOOKIE; 138 } 139 140 dirp->dd_flags = flags; 141 error = _initdir(dirp, fd, name); 142 if (error) { 143 errno = error; 144 goto error; 145 } 146 147 return (dirp); 148 error: 149 serrno = errno; 150 if (dirp != NULL) { 151 #ifdef _REENTRANT 152 if (__isthreaded) { 153 mutex_destroy((mutex_t *)dirp->dd_lock); 154 free(dirp->dd_lock); 155 } 156 #endif 157 free(dirp->dd_buf); 158 } 159 free(dirp); 160 if (fd != -1) 161 (void)close(fd); 162 errno = serrno; 163 return NULL; 164 } 165