/*
* Copyright (c) 2008, 2009, 2010, 2011
* Jonathan Schleifer <js@webkeks.org>
*
* All rights reserved.
*
* This file is part of ObjFW. It may be distributed under the terms of the
* Q Public License 1.0, which can be found in the file LICENSE.QPL included in
* the packaging of this file.
*
* Alternatively, it may be distributed under the terms of the GNU General
* Public License, either version 2 or 3, which can be found in the file
* LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
* file.
*/
/* Required to prevent a name conflict in glibc when using -fblocks */
#undef __USE_XOPEN
#include <unistd.h>
#import "OFStream.h"
/**
* \brief A stream that supports seeking.
*
* IMPORTANT: If you want to subclass this, override _seekToOffset:,
* _seekForwardWithOffset: and _seekToOffsetRelativeToEnd:, but nothing else.
* Those are not defined in the headers, but do the actual work.
* OFSeekableStream uses those and makes them work together with the caching of
* OFStream. If you override these methods without the _ prefix, you *WILL*
* break caching, get broken results and seek to the wrong position!
*/
@interface OFSeekableStream: OFStream
/**
* Seeks to the specified absolute offset.
*
* \param offset The offset in bytes
*/
- (void)seekToOffset: (off_t)offset;
/**
* Seeks to the specified offset, relative to the current location.
*
* \param offset The offset relative to the current location
* \return The absolute offset
*/
- (off_t)seekForwardWithOffset: (off_t)offset;
/**
* Seeks to the specified offset, relative to the end of the stream.
*
* \param offset The offset relative to the end of the stream
* \return The absolute offset
*/
- (off_t)seekToOffsetRelativeToEnd: (off_t)offset;
@end