1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* Copyright (c) 1988 AT&T */ 30 /* All Rights Reserved */ 31 32 33 /* 34 * seekdir -- C library extension routine 35 */ 36 37 #include <sys/feature_tests.h> 38 39 #if !defined(_LP64) 40 #pragma weak seekdir64 = _seekdir64 41 #endif 42 #pragma weak seekdir = _seekdir 43 44 #include "synonyms.h" 45 #include <mtlib.h> 46 #include <sys/types.h> 47 #include <fcntl.h> 48 #include <unistd.h> 49 #include <stdio.h> 50 #include <dirent.h> 51 #include <thread.h> 52 #include <synch.h> 53 54 55 extern mutex_t _dirent_lock; 56 57 #ifdef _LP64 58 59 void 60 seekdir(DIR *dirp, long loc) 61 { 62 struct dirent *dp; 63 off_t off = 0; 64 65 lmutex_lock(&_dirent_lock); 66 if (lseek(dirp->dd_fd, 0, SEEK_CUR) != 0) { 67 dp = (struct dirent *)(uintptr_t)&dirp->dd_buf[dirp->dd_loc]; 68 off = dp->d_off; 69 } 70 if (off != loc) { 71 dirp->dd_loc = 0; 72 (void) lseek(dirp->dd_fd, loc, SEEK_SET); 73 dirp->dd_size = 0; 74 75 /* 76 * Save seek offset in d_off field, in case telldir 77 * follows seekdir with no intervening call to readdir 78 */ 79 ((struct dirent *)(uintptr_t)&dirp->dd_buf[0])->d_off = loc; 80 } 81 lmutex_unlock(&_dirent_lock); 82 } 83 84 #else /* _LP64 */ 85 86 static void 87 seekdir64(DIR *dirp, off64_t loc) 88 { 89 struct dirent64 *dp64; 90 off64_t off = 0; 91 92 lmutex_lock(&_dirent_lock); 93 if (lseek64(dirp->dd_fd, 0, SEEK_CUR) != 0) { 94 dp64 = (struct dirent64 *) 95 (uintptr_t)&dirp->dd_buf[dirp->dd_loc]; 96 /* was converted by readdir and needs to be reversed */ 97 if (dp64->d_ino == (ino64_t)-1) { 98 struct dirent *dp32; 99 100 dp32 = (struct dirent *) 101 ((uintptr_t)dp64 + sizeof (ino64_t)); 102 dp64->d_ino = (ino64_t)dp32->d_ino; 103 dp64->d_off = (off64_t)dp32->d_off; 104 dp64->d_reclen = (unsigned short)(dp32->d_reclen + 105 ((char *)&dp64->d_off - (char *)dp64)); 106 } 107 off = dp64->d_off; 108 } 109 if (off != loc) { 110 dirp->dd_loc = 0; 111 (void) lseek64(dirp->dd_fd, loc, SEEK_SET); 112 dirp->dd_size = 0; 113 114 /* 115 * Save seek offset in d_off field, in case telldir 116 * follows seekdir with no intervening call to readdir 117 */ 118 ((struct dirent64 *)(uintptr_t)&dirp->dd_buf[0])->d_off = loc; 119 } 120 lmutex_unlock(&_dirent_lock); 121 } 122 123 void 124 seekdir(DIR *dirp, long loc) 125 { 126 seekdir64(dirp, (off64_t)loc); 127 } 128 129 #endif /* _LP64 */ 130