/* * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, * 2018, 2019, 2020 * Jonathan Schleifer * * 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. */ #ifndef __STDC_LIMIT_MACROS # define __STDC_LIMIT_MACROS #endif #ifndef __STDC_CONSTANT_MACROS # define __STDC_CONSTANT_MACROS #endif #include "objfw-defs.h" #ifdef OF_HAVE_SYS_TYPES_H # include #endif #import "OFStream.h" OF_ASSUME_NONNULL_BEGIN #if defined(OF_WINDOWS) typedef __int64 of_offset_t; #elif defined(OF_ANDROID) typedef long long of_offset_t; #elif defined(OF_MORPHOS) typedef signed long long of_offset_t; #elif defined(OF_HAVE_OFF64_T) typedef off64_t of_offset_t; #else typedef off_t of_offset_t; #endif /*! * @class OFSeekableStream OFSeekableStream.h ObjFW/OFSeekableStream.h * * @brief A stream that supports seeking. * * @note If you want to subclass this, override * @ref lowlevelSeekToOffset:whence:. OFSeekableStream uses this method * and makes it work together with the caching of OFStream. If you * override this methods without the `lowlevel` prefix, you *will* break * caching, get broken results and seek to the wrong position! */ @interface OFSeekableStream: OFStream { OF_RESERVE_IVARS(4) } /*! * @brief Seeks to the specified absolute offset. * * @param offset The offset in bytes * @param whence From where to seek.@n * Possible values are: * Value | Description * -----------|--------------------------------------- * `SEEK_SET` | Seek to the specified byte * `SEEK_CUR` | Seek to the current location + offset * `SEEK_END` | Seek to the end of the stream + offset * @return The new offset form the start of the file */ - (of_offset_t)seekToOffset: (of_offset_t)offset whence: (int)whence; /*! * @brief Seek the stream on the lowlevel. * * @warning Do not call this directly! * * @note Override this method with your actual seek implementation when * subclassing! * * @param offset The offset to seek to * @param whence From where to seek.@n * Possible values are: * Value | Description * -----------|--------------------------------------- * `SEEK_SET` | Seek to the specified byte * `SEEK_CUR` | Seek to the current location + offset * `SEEK_END` | Seek to the end of the stream + offset * @return The new offset from the start of the file */ - (of_offset_t)lowlevelSeekToOffset: (of_offset_t)offset whence: (int)whence; @end OF_ASSUME_NONNULL_END