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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD$ 34 * 35 */ 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 static char sccsid[] = "@(#)readdir.c 8.3 (Berkeley) 9/29/94"; 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include <sys/param.h> 43 #include <dirent.h> 44 #include <errno.h> 45 #include <string.h> 46 #include <pthread.h> 47 #include "un-namespace.h" 48 49 #include "libc_private.h" 50 51 /* 52 * get next entry in a directory. 53 */ 54 struct dirent * 55 _readdir_unlocked(dirp) 56 DIR *dirp; 57 { 58 struct dirent *dp; 59 60 for (;;) { 61 if (dirp->dd_loc >= dirp->dd_size) { 62 if (dirp->dd_flags & __DTF_READALL) 63 return (NULL); 64 dirp->dd_loc = 0; 65 } 66 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 67 dirp->dd_size = _getdirentries(dirp->dd_fd, 68 dirp->dd_buf, dirp->dd_len, &dirp->dd_seek); 69 if (dirp->dd_size <= 0) 70 return (NULL); 71 } 72 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 73 if ((long)dp & 03L) /* bogus pointer check */ 74 return (NULL); 75 if (dp->d_reclen <= 0 || 76 dp->d_reclen > dirp->dd_len + 1 - dirp->dd_loc) 77 return (NULL); 78 dirp->dd_loc += dp->d_reclen; 79 if (dp->d_ino == 0) 80 continue; 81 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 82 continue; 83 return (dp); 84 } 85 } 86 87 struct dirent * 88 readdir(dirp) 89 DIR *dirp; 90 { 91 struct dirent *dp; 92 93 if (__isthreaded) { 94 _pthread_mutex_lock((pthread_mutex_t *)&dirp->dd_lock); 95 dp = _readdir_unlocked(dirp); 96 _pthread_mutex_unlock((pthread_mutex_t *)&dirp->dd_lock); 97 } 98 else 99 dp = _readdir_unlocked(dirp); 100 return (dp); 101 } 102 103 int 104 readdir_r(dirp, entry, result) 105 DIR *dirp; 106 struct dirent *entry; 107 struct dirent **result; 108 { 109 struct dirent *dp; 110 int saved_errno; 111 112 saved_errno = errno; 113 errno = 0; 114 if (__isthreaded) { 115 _pthread_mutex_lock((pthread_mutex_t *)&dirp->dd_lock); 116 if ((dp = _readdir_unlocked(dirp)) != NULL) 117 memcpy(entry, dp, sizeof *entry); 118 _pthread_mutex_unlock((pthread_mutex_t *)&dirp->dd_lock); 119 } 120 else if ((dp = _readdir_unlocked(dirp)) != NULL) 121 memcpy(entry, dp, sizeof *entry); 122 123 if (errno != 0) { 124 if (dp == NULL) 125 return (errno); 126 } else 127 errno = saved_errno; 128 129 if (dp != NULL) 130 *result = entry; 131 else 132 *result = NULL; 133 134 return (0); 135 } 136