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 1.2 2003/06/17 04:26:42 dillon Exp $ 35 * 36 * @(#)readdir.c 8.3 (Berkeley) 9/29/94 37 */ 38 39 #include <sys/param.h> 40 #include <dirent.h> 41 #include <errno.h> 42 #include <string.h> 43 #ifdef _THREAD_SAFE 44 #include <pthread.h> 45 #include "pthread_private.h" 46 #endif /* _THREAD_SAFE */ 47 48 /* 49 * get next entry in a directory. 50 */ 51 struct dirent * 52 readdir(dirp) 53 DIR *dirp; 54 { 55 struct dirent *dp; 56 57 for (;;) { 58 if (dirp->dd_loc >= dirp->dd_size) { 59 if (dirp->dd_flags & __DTF_READALL) 60 return (NULL); 61 dirp->dd_loc = 0; 62 } 63 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 64 dirp->dd_size = getdirentries(dirp->dd_fd, 65 dirp->dd_buf, dirp->dd_len, &dirp->dd_seek); 66 if (dirp->dd_size <= 0) 67 return (NULL); 68 } 69 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 70 if ((long)dp & 03L) /* bogus pointer check */ 71 return (NULL); 72 if (dp->d_reclen <= 0 || 73 dp->d_reclen > dirp->dd_len + 1 - dirp->dd_loc) 74 return (NULL); 75 dirp->dd_loc += dp->d_reclen; 76 if (dp->d_ino == 0) 77 continue; 78 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 79 continue; 80 return (dp); 81 } 82 } 83 84 int 85 readdir_r(dirp, entry, result) 86 DIR *dirp; 87 struct dirent *entry; 88 struct dirent **result; 89 { 90 struct dirent *dp; 91 int ret, saved_errno; 92 93 #ifdef _THREAD_SAFE 94 if ((ret = _FD_LOCK(dirp->dd_fd, FD_READ, NULL)) != 0) 95 return (ret); 96 #endif 97 98 saved_errno = errno; 99 errno = 0; 100 dp = readdir(dirp); 101 if (errno != 0) { 102 if (dp == NULL) { 103 #ifdef _THREAD_SAFE 104 _FD_UNLOCK(dirp->dd_fd, FD_READ); 105 #endif 106 return (errno); 107 } 108 } else 109 errno = saved_errno; 110 111 if (dp != NULL) 112 memcpy(entry, dp, _GENERIC_DIRSIZ(dp)); 113 114 #ifdef _THREAD_SAFE 115 _FD_UNLOCK(dirp->dd_fd, FD_READ); 116 #endif 117 118 if (dp != NULL) 119 *result = entry; 120 else 121 *result = NULL; 122 123 return (0); 124 } 125