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 * ftruncate() and truncate() set a file to a specified 35 * length using fcntl(F_FREESP) system call. If the file 36 * was previously longer than length, the bytes past the 37 * length will no longer be accessible. If it was shorter, 38 * bytes not written will be zero filled. 39 */ 40 41 #include <sys/feature_tests.h> 42 43 #if !defined(_LP64) && _FILE_OFFSET_BITS == 64 44 #pragma weak ftruncate64 = _ftruncate64 45 #pragma weak truncate64 = _truncate64 46 #define _ftruncate _ftruncate64 47 #define _truncate _truncate64 48 #else /* !_LP64 && _FILE_OFFSET_BITS == 64 */ 49 #pragma weak ftruncate = _ftruncate 50 #pragma weak truncate = _truncate 51 #endif /* !_LP64 && _FILE_OFFSET_BITS == 64 */ 52 53 #include "synonyms.h" 54 #include <unistd.h> 55 #include <stdio.h> 56 #include <fcntl.h> 57 #include <sys/types.h> 58 59 int 60 _ftruncate(int fildes, off_t len) 61 { 62 struct flock lck; 63 64 lck.l_whence = 0; /* offset l_start from beginning of file */ 65 lck.l_start = len; 66 lck.l_type = F_WRLCK; /* setting a write lock */ 67 lck.l_len = (off_t)0; /* until the end of the file address space */ 68 69 if (fcntl(fildes, F_FREESP, &lck) == -1) { 70 return (-1); 71 } 72 return (0); 73 } 74 75 int 76 _truncate(const char *path, off_t len) 77 { 78 79 int fd; 80 81 if ((fd = open(path, O_WRONLY)) == -1) { 82 return (-1); 83 } 84 85 if (ftruncate(fd, len) == -1) { 86 (void) close(fd); 87 return (-1); 88 } 89 90 (void) close(fd); 91 return (0); 92 } 93