1 /* 2 * Copyright (c) 1983, 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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #if defined(LIBC_SCCS) && !defined(lint) 31 static char sccsid[] = "@(#)readdir.c 8.3 (Berkeley) 9/29/94"; 32 #endif /* LIBC_SCCS and not lint */ 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include "namespace.h" 37 #include <sys/param.h> 38 #include <dirent.h> 39 #include <errno.h> 40 #include <string.h> 41 #include <pthread.h> 42 #include "un-namespace.h" 43 44 #include "libc_private.h" 45 #include "telldir.h" 46 47 /* 48 * get next entry in a directory. 49 */ 50 struct dirent * 51 _readdir_unlocked(dirp) 52 DIR *dirp; 53 { 54 struct dirent *dp; 55 56 for (;;) { 57 if (dirp->dd_loc >= dirp->dd_size) { 58 if (dirp->dd_flags & __DTF_READALL) 59 return (NULL); 60 dirp->dd_loc = 0; 61 } 62 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 63 dirp->dd_size = _getdirentries(dirp->dd_fd, 64 dirp->dd_buf, dirp->dd_len, &dirp->dd_seek); 65 if (dirp->dd_size <= 0) 66 return (NULL); 67 } 68 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 69 if ((long)dp & 03L) /* bogus pointer check */ 70 return (NULL); 71 if (dp->d_reclen <= 0 || 72 dp->d_reclen > dirp->dd_len + 1 - dirp->dd_loc) 73 return (NULL); 74 dirp->dd_loc += dp->d_reclen; 75 if (dp->d_ino == 0) 76 continue; 77 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 78 continue; 79 return (dp); 80 } 81 } 82 83 struct dirent * 84 readdir(dirp) 85 DIR *dirp; 86 { 87 struct dirent *dp; 88 89 if (__isthreaded) { 90 _pthread_mutex_lock(&dirp->dd_lock); 91 dp = _readdir_unlocked(dirp); 92 _pthread_mutex_unlock(&dirp->dd_lock); 93 } 94 else 95 dp = _readdir_unlocked(dirp); 96 return (dp); 97 } 98 99 int 100 readdir_r(dirp, entry, result) 101 DIR *dirp; 102 struct dirent *entry; 103 struct dirent **result; 104 { 105 struct dirent *dp; 106 int saved_errno; 107 108 saved_errno = errno; 109 errno = 0; 110 if (__isthreaded) { 111 _pthread_mutex_lock(&dirp->dd_lock); 112 if ((dp = _readdir_unlocked(dirp)) != NULL) 113 memcpy(entry, dp, _GENERIC_DIRSIZ(dp)); 114 _pthread_mutex_unlock(&dirp->dd_lock); 115 } 116 else if ((dp = _readdir_unlocked(dirp)) != NULL) 117 memcpy(entry, dp, _GENERIC_DIRSIZ(dp)); 118 119 if (errno != 0) { 120 if (dp == NULL) 121 return (errno); 122 } else 123 errno = saved_errno; 124 125 if (dp != NULL) 126 *result = entry; 127 else 128 *result = NULL; 129 130 return (0); 131 } 132