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 * $FreeBSD$ 34 * 35 */ 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 static char sccsid[] = "@(#)readdir.c 8.3 (Berkeley) 9/29/94"; 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include <sys/param.h> 42 #include <dirent.h> 43 #include <errno.h> 44 #include <string.h> 45 #ifdef _THREAD_SAFE 46 #include <pthread.h> 47 #include "pthread_private.h" 48 #endif _THREAD_SAFE 49 50 /* 51 * get next entry in a directory. 52 */ 53 struct dirent * 54 readdir(dirp) 55 register DIR *dirp; 56 { 57 register struct dirent *dp; 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_size = getdirentries(dirp->dd_fd, 67 dirp->dd_buf, dirp->dd_len, &dirp->dd_seek); 68 if (dirp->dd_size <= 0) 69 return (NULL); 70 } 71 dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc); 72 if ((long)dp & 03L) /* bogus pointer check */ 73 return (NULL); 74 if (dp->d_reclen <= 0 || 75 dp->d_reclen > dirp->dd_len + 1 - dirp->dd_loc) 76 return (NULL); 77 dirp->dd_loc += dp->d_reclen; 78 if (dp->d_ino == 0) 79 continue; 80 if (dp->d_type == DT_WHT && (dirp->dd_flags & DTF_HIDEW)) 81 continue; 82 return (dp); 83 } 84 } 85 86 int 87 readdir_r(dirp, entry, result) 88 DIR *dirp; 89 struct dirent *entry; 90 struct dirent **result; 91 { 92 struct dirent *dp; 93 int ret, saved_errno; 94 95 #ifdef _THREAD_SAFE 96 if ((ret = _FD_LOCK(dirp->dd_fd, FD_READ, NULL)) != 0) 97 return (ret); 98 #endif 99 100 saved_errno = errno; 101 errno = 0; 102 dp = readdir(dirp); 103 if (errno != 0) { 104 if (dp == NULL) { 105 #ifdef _THREAD_SAFE 106 _FD_UNLOCK(dirp->dd_fd, FD_READ); 107 #endif 108 return (errno); 109 } 110 } else 111 errno = saved_errno; 112 113 if (dp != NULL) 114 memcpy(entry, dp, sizeof *entry); 115 116 #ifdef _THREAD_SAFE 117 _FD_UNLOCK(dirp->dd_fd, FD_READ); 118 #endif 119 120 if (dp != NULL) 121 *result = entry; 122 else 123 *result = NULL; 124 125 return (0); 126 } 127