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. 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 * $FreeBSD: src/lib/libc/gen/readdir.c,v 1.5.2.4 2002/02/26 22:53:57 alfred Exp $ 30 * 31 * @(#)readdir.c 8.3 (Berkeley) 9/29/94 32 */ 33 34 #include "namespace.h" 35 #include <sys/param.h> 36 #include <sys/file.h> 37 #include <dirent.h> 38 #include <errno.h> 39 #include <string.h> 40 #include <pthread.h> 41 #include "un-namespace.h" 42 43 #include "libc_private.h" 44 #include "gen_private.h" 45 46 /* 47 * get next entry in a directory. 48 */ 49 struct dirent * 50 _readdir_unlocked(DIR *dirp, int skipdeleted) 51 { 52 struct dirent *dp; 53 long dummy; 54 55 for (;;) { 56 if (dirp->dd_loc >= dirp->dd_size) { 57 if (dirp->dd_flags & __DTF_READALL) 58 return (NULL); 59 dirp->dd_loc = 0; 60 } 61 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 62 dirp->dd_seek = lseek(dirp->dd_fd, 0, SEEK_CUR); 63 dirp->dd_size = _getdirentries(dirp->dd_fd, 64 dirp->dd_buf, dirp->dd_len, &dummy); 65 if (dirp->dd_size <= 0) 66 return (NULL); 67 } 68 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 69 if (_DIRENT_DIRSIZ(dp) > dirp->dd_len + 1 - dirp->dd_loc) 70 return (NULL); 71 dirp->dd_loc += _DIRENT_DIRSIZ(dp); 72 73 if (skipdeleted) { 74 if (dp->d_ino == 0) 75 continue; 76 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 77 continue; 78 } 79 return (dp); 80 } 81 } 82 83 struct dirent * 84 readdir(DIR *dirp) 85 { 86 struct dirent *dp; 87 88 if (__isthreaded) 89 _pthread_mutex_lock(&dirp->dd_lock); 90 dp = _readdir_unlocked(dirp, 1); 91 if (__isthreaded) 92 _pthread_mutex_unlock(&dirp->dd_lock); 93 94 return (dp); 95 } 96 97 int 98 readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result) 99 { 100 struct dirent *dp; 101 int saved_errno; 102 103 saved_errno = errno; 104 errno = 0; 105 if (__isthreaded) 106 _pthread_mutex_lock(&dirp->dd_lock); 107 if ((dp = _readdir_unlocked(dirp, 1)) != NULL) 108 memcpy(entry, dp, _DIRENT_MINSIZ(dp)); 109 if (__isthreaded) 110 _pthread_mutex_unlock(&dirp->dd_lock); 111 112 if (errno != 0) { 113 if (dp == NULL) { 114 return (errno); 115 } 116 } else 117 errno = saved_errno; 118 119 if (dp != NULL) 120 *result = entry; 121 else 122 *result = NULL; 123 124 return (0); 125 } 126