KIO
klimitediodevice.cpp
Go to the documentation of this file.00001 /* This file is part of the KDE libraries 00002 Copyright (C) 2001, 2002, 2007 David Faure <faure@kde.org> 00003 00004 This library is free software; you can redistribute it and/or 00005 modify it under the terms of the GNU Library General Public 00006 License version 2 as published by the Free Software Foundation. 00007 00008 This library is distributed in the hope that it will be useful, 00009 but WITHOUT ANY WARRANTY; without even the implied warranty of 00010 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00011 Library General Public License for more details. 00012 00013 You should have received a copy of the GNU Library General Public License 00014 along with this library; see the file COPYING.LIB. If not, write to 00015 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 00016 Boston, MA 02110-1301, USA. 00017 */ 00018 00019 #include "klimitediodevice.h" 00020 00021 KLimitedIODevice::KLimitedIODevice( QIODevice *dev, int start, int length ) 00022 : m_dev( dev ), m_start( start ), m_length( length ) 00023 { 00024 //kDebug(7005) << "start=" << start << "length=" << length; 00025 open( QIODevice::ReadOnly ); //krazy:exclude=syscalls 00026 } 00027 00028 bool KLimitedIODevice::open( QIODevice::OpenMode m ) 00029 { 00030 //kDebug(7005) << "m=" << m; 00031 if ( m & QIODevice::ReadOnly ) { 00032 /*bool ok = false; 00033 if ( m_dev->isOpen() ) 00034 ok = ( m_dev->mode() == QIODevice::ReadOnly ); 00035 else 00036 ok = m_dev->open( m ); 00037 if ( ok )*/ 00038 m_dev->seek( m_start ); // No concurrent access ! 00039 } 00040 else 00041 kWarning(7005) << "KLimitedIODevice::open only supports QIODevice::ReadOnly!"; 00042 setOpenMode( QIODevice::ReadOnly ); 00043 return true; 00044 } 00045 00046 void KLimitedIODevice::close() 00047 { 00048 } 00049 00050 qint64 KLimitedIODevice::size() const 00051 { 00052 return m_length; 00053 } 00054 00055 qint64 KLimitedIODevice::readData( char * data, qint64 maxlen ) 00056 { 00057 maxlen = qMin( maxlen, m_length - pos() ); // Apply upper limit 00058 return m_dev->read( data, maxlen ); 00059 } 00060 00061 bool KLimitedIODevice::seek( qint64 pos ) 00062 { 00063 Q_ASSERT( pos <= m_length ); 00064 pos = qMin( pos, m_length ); // Apply upper limit 00065 return m_dev->seek( m_start + pos ); 00066 } 00067 00068 qint64 KLimitedIODevice::bytesAvailable() const 00069 { 00070 return m_length + QIODevice::bytesAvailable(); 00071 } 00072 00073 bool KLimitedIODevice::isSequential() const 00074 { 00075 return m_dev->isSequential(); 00076 }