1 /** @file 2 Get next entry in a directory. 3 4 Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR> 5 This program and the accompanying materials 6 are licensed and made available under the terms and conditions of the BSD License 7 which accompanies this distribution. The full text of the license may be found at 8 http://opensource.org/licenses/bsd-license.php 9 10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 12 13 Copyright (c) 1983, 1993 14 The Regents of the University of California. All rights reserved. 15 16 Redistribution and use in source and binary forms, with or without 17 modification, are permitted provided that the following conditions 18 are met: 19 1. Redistributions of source code must retain the above copyright 20 notice, this list of conditions and the following disclaimer. 21 2. Redistributions in binary form must reproduce the above copyright 22 notice, this list of conditions and the following disclaimer in the 23 documentation and/or other materials provided with the distribution. 24 3. Neither the name of the University nor the names of its contributors 25 may be used to endorse or promote products derived from this software 26 without specific prior written permission. 27 28 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 SUCH DAMAGE. 39 40 NetBSD: readdir.c,v 1.24 2008/05/04 18:53:26 tonnerre Exp 41 readdir.c 8.3 (Berkeley) 9/29/94 42 */ 43 #include <sys/cdefs.h> 44 45 #include <namespace.h> 46 #include <reentrant.h> 47 #include <extern.h> 48 #include <sys/param.h> 49 #include <sys/stdint.h> 50 51 #include <stdio.h> 52 #include <dirent.h> 53 #include <errno.h> 54 #include <string.h> 55 #include <unistd.h> 56 57 /* 58 * get next entry in a directory. 59 */ 60 struct dirent * 61 _readdir_unlocked(DIR *dirp, int skipdeleted) 62 { 63 struct dirent *dp; 64 65 66 for (;;) { 67 if (dirp->dd_loc >= dirp->dd_size) { 68 if (dirp->dd_flags & __DTF_READALL) 69 return (NULL); 70 dirp->dd_loc = 0; 71 } 72 if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) { 73 dirp->dd_size = (long)read(dirp->dd_fd, dirp->dd_buf, (size_t)dirp->dd_len); 74 if (dirp->dd_size <= 0) 75 return (NULL); 76 } 77 dp = (struct dirent *) (void *)(dirp->dd_buf + (size_t)dirp->dd_loc); 78 if ((intptr_t)dp & _DIRENT_ALIGN(dp))/* bogus pointer check */ 79 return (NULL); 80 dirp->dd_loc += (long)dp->Size; 81 if ((dp->Attribute & DT_HIDDEN) && (dirp->dd_flags & DTF_HIDEW)) 82 continue; 83 return (dp); 84 } 85 } 86 87 struct dirent * 88 readdir(DIR *dirp) 89 { 90 struct dirent *dp; 91 92 #ifdef _REENTRANT 93 if (__isthreaded) { 94 mutex_lock((mutex_t *)dirp->dd_lock); 95 dp = _readdir_unlocked(dirp, 1); 96 mutex_unlock((mutex_t *)dirp->dd_lock); 97 } 98 else 99 #endif 100 dp = _readdir_unlocked(dirp, 1); 101 return (dp); 102 } 103 104 int 105 readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result) 106 { 107 struct dirent *dp; 108 int saved_errno; 109 110 saved_errno = errno; 111 errno = 0; 112 #ifdef _REENTRANT 113 if (__isthreaded) { 114 mutex_lock((mutex_t *)dirp->dd_lock); 115 if ((dp = _readdir_unlocked(dirp, 1)) != NULL) 116 memcpy(entry, dp, (size_t)_DIRENT_SIZE(dp)); 117 mutex_unlock((mutex_t *)dirp->dd_lock); 118 } 119 else 120 #endif 121 if ((dp = _readdir_unlocked(dirp, 1)) != NULL) 122 memcpy(entry, dp, (size_t)_DIRENT_SIZE(dp)); 123 124 if (errno != 0) { 125 if (dp == NULL) 126 return (errno); 127 } else 128 errno = saved_errno; 129 130 if (dp != NULL) 131 *result = entry; 132 else 133 *result = NULL; 134 135 return (0); 136 } 137