17c478bd9Sstevel@tonic-gate /* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5a574db85Sraf * Common Development and Distribution License (the "License"). 6a574db85Sraf * You may not use this file except in compliance with the License. 77c478bd9Sstevel@tonic-gate * 87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 117c478bd9Sstevel@tonic-gate * and limitations under the License. 127c478bd9Sstevel@tonic-gate * 137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 187c478bd9Sstevel@tonic-gate * 197c478bd9Sstevel@tonic-gate * CDDL HEADER END 207c478bd9Sstevel@tonic-gate */ 21a574db85Sraf 227c478bd9Sstevel@tonic-gate /* 23a574db85Sraf * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 247c478bd9Sstevel@tonic-gate * Use is subject to license terms. 257c478bd9Sstevel@tonic-gate */ 267c478bd9Sstevel@tonic-gate 277c478bd9Sstevel@tonic-gate /* Copyright (c) 1988 AT&T */ 287c478bd9Sstevel@tonic-gate /* All Rights Reserved */ 297c478bd9Sstevel@tonic-gate 30*7257d1b4Sraf #pragma ident "%Z%%M% %I% %E% SMI" 317c478bd9Sstevel@tonic-gate 327c478bd9Sstevel@tonic-gate /* 337c478bd9Sstevel@tonic-gate * ftruncate() and truncate() set a file to a specified 347c478bd9Sstevel@tonic-gate * length using fcntl(F_FREESP) system call. If the file 357c478bd9Sstevel@tonic-gate * was previously longer than length, the bytes past the 367c478bd9Sstevel@tonic-gate * length will no longer be accessible. If it was shorter, 377c478bd9Sstevel@tonic-gate * bytes not written will be zero filled. 387c478bd9Sstevel@tonic-gate */ 397c478bd9Sstevel@tonic-gate 407c478bd9Sstevel@tonic-gate #include <sys/feature_tests.h> 417c478bd9Sstevel@tonic-gate 427c478bd9Sstevel@tonic-gate #if !defined(_LP64) && _FILE_OFFSET_BITS == 64 43*7257d1b4Sraf #pragma weak _ftruncate64 = ftruncate64 44*7257d1b4Sraf #pragma weak _truncate64 = truncate64 45*7257d1b4Sraf #define ftruncate ftruncate64 46*7257d1b4Sraf #define truncate truncate64 477c478bd9Sstevel@tonic-gate #endif /* !_LP64 && _FILE_OFFSET_BITS == 64 */ 487c478bd9Sstevel@tonic-gate 49*7257d1b4Sraf #include "lint.h" 507c478bd9Sstevel@tonic-gate #include <unistd.h> 517c478bd9Sstevel@tonic-gate #include <stdio.h> 527c478bd9Sstevel@tonic-gate #include <fcntl.h> 53a574db85Sraf #include <pthread.h> 547c478bd9Sstevel@tonic-gate #include <sys/types.h> 557c478bd9Sstevel@tonic-gate 567c478bd9Sstevel@tonic-gate int 57*7257d1b4Sraf ftruncate(int fildes, off_t len) 587c478bd9Sstevel@tonic-gate { 597c478bd9Sstevel@tonic-gate struct flock lck; 607c478bd9Sstevel@tonic-gate 617c478bd9Sstevel@tonic-gate lck.l_whence = 0; /* offset l_start from beginning of file */ 627c478bd9Sstevel@tonic-gate lck.l_start = len; 637c478bd9Sstevel@tonic-gate lck.l_type = F_WRLCK; /* setting a write lock */ 647c478bd9Sstevel@tonic-gate lck.l_len = (off_t)0; /* until the end of the file address space */ 657c478bd9Sstevel@tonic-gate 667c478bd9Sstevel@tonic-gate if (fcntl(fildes, F_FREESP, &lck) == -1) { 677c478bd9Sstevel@tonic-gate return (-1); 687c478bd9Sstevel@tonic-gate } 697c478bd9Sstevel@tonic-gate return (0); 707c478bd9Sstevel@tonic-gate } 717c478bd9Sstevel@tonic-gate 727c478bd9Sstevel@tonic-gate int 73*7257d1b4Sraf truncate(const char *path, off_t len) 747c478bd9Sstevel@tonic-gate { 757c478bd9Sstevel@tonic-gate 76a574db85Sraf int rval = 0; 77a574db85Sraf int cancel_state; 787c478bd9Sstevel@tonic-gate int fd; 797c478bd9Sstevel@tonic-gate 80a574db85Sraf /* 81a574db85Sraf * truncate() is not a cancellation point, 82a574db85Sraf * even though it calls open() and close(). 83a574db85Sraf */ 84a574db85Sraf (void) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cancel_state); 85a574db85Sraf if ((fd = open(path, O_WRONLY)) == -1 || ftruncate(fd, len) == -1) 86a574db85Sraf rval = -1; 87a574db85Sraf if (fd >= 0) 887c478bd9Sstevel@tonic-gate (void) close(fd); 89a574db85Sraf (void) pthread_setcancelstate(cancel_state, NULL); 90a574db85Sraf return (rval); 917c478bd9Sstevel@tonic-gate } 92