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: src/lib/libc/gen/readdir.c,v 1.5.2.4 2002/02/26 22:53:57 alfred Exp $ 34 * $DragonFly: src/lib/libc/gen/readdir.c,v 1.6 2005/08/27 20:23:05 joerg Exp $ 35 * 36 * @(#)readdir.c 8.3 (Berkeley) 9/29/94 37 */ 38 39 #include "namespace.h" 40 #include <sys/param.h> 41 #include <dirent.h> 42 #include <errno.h> 43 #include <string.h> 44 #include <pthread.h> 45 #include "un-namespace.h" 46 47 #include "libc_private.h" 48 49 /* 50 * get next entry in a directory. 51 */ 52 struct dirent * 53 _readdir_unlocked(dirp) 54 DIR *dirp; 55 { 56 struct dirent *dp; 57 58 for (;;) { 59 if (dirp->dd_loc >= dirp->dd_size) { 60 if (dirp->dd_flags & __DTF_READALL) 61 return (NULL); 62 dirp->dd_loc = 0; 63 } 64 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 65 dirp->dd_size = _getdirentries(dirp->dd_fd, 66 dirp->dd_buf, dirp->dd_len, &dirp->dd_seek); 67 if (dirp->dd_size <= 0) 68 return (NULL); 69 } 70 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 71 if (_DIRENT_DIRSIZ(dp) > dirp->dd_len + 1 - dirp->dd_loc) 72 return (NULL); 73 dirp->dd_loc += _DIRENT_DIRSIZ(dp); 74 if (dp->d_ino == 0) 75 continue; 76 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 77 continue; 78 return (dp); 79 } 80 } 81 82 struct dirent * 83 readdir(dirp) 84 DIR *dirp; 85 { 86 struct dirent *dp; 87 88 if (__isthreaded) 89 _pthread_mutex_lock((pthread_mutex_t *)&dirp->dd_lock); 90 dp = _readdir_unlocked(dirp); 91 if (__isthreaded) 92 _pthread_mutex_unlock((pthread_mutex_t *)&dirp->dd_lock); 93 94 return (dp); 95 } 96 97 int 98 readdir_r(dirp, entry, result) 99 DIR *dirp; 100 struct dirent *entry; 101 struct dirent **result; 102 { 103 struct dirent *dp; 104 int ret, saved_errno; 105 106 saved_errno = errno; 107 errno = 0; 108 if (__isthreaded) 109 _pthread_mutex_lock((pthread_mutex_t *)&dirp->dd_lock); 110 if ((dp = _readdir_unlocked(dirp)) != NULL) 111 memcpy(entry, dp, _DIRENT_MINSIZ(dp)); 112 if (__isthreaded) 113 _pthread_mutex_unlock((pthread_mutex_t *)&dirp->dd_lock); 114 115 if (errno != 0) { 116 if (dp == NULL) { 117 return (errno); 118 } 119 } else 120 errno = saved_errno; 121 122 if (dp != NULL) 123 *result = entry; 124 else 125 *result = NULL; 126 127 return (0); 128 } 129