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 * 35 * @(#)readdir.c 8.3 (Berkeley) 9/29/94 36 */ 37 38 #include "namespace.h" 39 #include <sys/param.h> 40 #include <sys/file.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 #include "gen_private.h" 49 50 /* 51 * get next entry in a directory. 52 */ 53 struct dirent * 54 _readdir_unlocked(DIR *dirp, int skipdeleted) 55 { 56 struct dirent *dp; 57 long dummy; 58 59 for (;;) { 60 if (dirp->dd_loc >= dirp->dd_size) { 61 if (dirp->dd_flags & __DTF_READALL) 62 return (NULL); 63 dirp->dd_loc = 0; 64 } 65 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 66 dirp->dd_seek = lseek(dirp->dd_fd, 0, SEEK_CUR); 67 dirp->dd_size = _getdirentries(dirp->dd_fd, 68 dirp->dd_buf, dirp->dd_len, &dummy); 69 if (dirp->dd_size <= 0) 70 return (NULL); 71 } 72 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 73 if (_DIRENT_DIRSIZ(dp) > dirp->dd_len + 1 - dirp->dd_loc) 74 return (NULL); 75 dirp->dd_loc += _DIRENT_DIRSIZ(dp); 76 77 if (skipdeleted) { 78 if (dp->d_ino == 0) 79 continue; 80 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 81 continue; 82 } 83 return (dp); 84 } 85 } 86 87 struct dirent * 88 readdir(DIR *dirp) 89 { 90 struct dirent *dp; 91 92 if (__isthreaded) 93 _pthread_mutex_lock(&dirp->dd_lock); 94 dp = _readdir_unlocked(dirp, 1); 95 if (__isthreaded) 96 _pthread_mutex_unlock(&dirp->dd_lock); 97 98 return (dp); 99 } 100 101 int 102 readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result) 103 { 104 struct dirent *dp; 105 int saved_errno; 106 107 saved_errno = errno; 108 errno = 0; 109 if (__isthreaded) 110 _pthread_mutex_lock(&dirp->dd_lock); 111 if ((dp = _readdir_unlocked(dirp, 1)) != NULL) 112 memcpy(entry, dp, _DIRENT_MINSIZ(dp)); 113 if (__isthreaded) 114 _pthread_mutex_unlock(&dirp->dd_lock); 115 116 if (errno != 0) { 117 if (dp == NULL) { 118 return (errno); 119 } 120 } else 121 errno = saved_errno; 122 123 if (dp != NULL) 124 *result = entry; 125 else 126 *result = NULL; 127 128 return (0); 129 } 130