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 (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 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 <pthread.h> 58 #include <sys/types.h> 59 60 int 61 _ftruncate(int fildes, off_t len) 62 { 63 struct flock lck; 64 65 lck.l_whence = 0; /* offset l_start from beginning of file */ 66 lck.l_start = len; 67 lck.l_type = F_WRLCK; /* setting a write lock */ 68 lck.l_len = (off_t)0; /* until the end of the file address space */ 69 70 if (fcntl(fildes, F_FREESP, &lck) == -1) { 71 return (-1); 72 } 73 return (0); 74 } 75 76 int 77 _truncate(const char *path, off_t len) 78 { 79 80 int rval = 0; 81 int cancel_state; 82 int fd; 83 84 /* 85 * truncate() is not a cancellation point, 86 * even though it calls open() and close(). 87 */ 88 (void) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cancel_state); 89 if ((fd = open(path, O_WRONLY)) == -1 || ftruncate(fd, len) == -1) 90 rval = -1; 91 if (fd >= 0) 92 (void) close(fd); 93 (void) pthread_setcancelstate(cancel_state, NULL); 94 return (rval); 95 } 96