[pclasses-cvs] pclasses2/src/IO ZLibIOFilter.cpp,NONE,1.1

[Christian P. <cp...@us...>]

Update of /cvsroot/pclasses/pclasses2/src/IO
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv11889/src/IO

Added Files:
	ZLibIOFilter.cpp 
Log Message:
Added ZLibIOFilter as promised to Stephan ;-)


--- NEW FILE: ZLibIOFilter.cpp ---
/***************************************************************************
 *   Copyright (C) 2004 by Christian Prochnow                              *
 *   cp...@se...                                                   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU Library General Public License as       *
 *   published by the Free Software Foundation; either version 2 of the    *
 *   License, or (at your option) any later version.                       *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU Library General Public     *
 *   License along with this program; if not, write to the                 *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include <pclasses/IO/ZLibIOFilter.h>

namespace P {

namespace IO {

ZLibIOFilter::ZLibIOFilter()
: _strmOut(0), _strmIn(0)
{
}

ZLibIOFilter::~ZLibIOFilter()
{
	if(_strmOut)
		delete _strmOut;

	if(_strmIn)
		delete _strmIn;
}

IOFilter* ZLibIOFilter::create()
{
	return new ZLibIOFilter();
}

void ZLibIOFilter::sync(bool close)
{
	// sync output stream ...
	if(_strmOut)
	{
		if(close)
		{
			while(!_strmOut->finish())
				flushAvailBytes();
			
			flushAvailBytes();
			_strmOut->reset();
		}
		else
		{
			_strmOut->sync();
			flushAvailBytes();
		}
	}

	if(_strmIn)
	{
		if(close)
			_strmIn->reset();
	}

	IOFilter::sync(close);
}

bool ZLibIOFilter::isSeekable()
{
	// seeking is too complex (for now ;-)
	return false;
}

size_t ZLibIOFilter::read(char* buffer, size_t count) throw(IO::IOError)
{
	if(!_strmIn)
		_strmIn = new P::IO::ZLibInputStream();

	if(_strmIn->bytesAvail() < count)
	{
		// refill output buffer ...
		char tmp[1024];
		size_t got = IOFilter::read(tmp, sizeof(tmp));
		
		size_t consumed = _strmIn->inflate(tmp, got);
		if(consumed < sizeof(tmp))
		{
			//@fixme: we need to buffer rememaining bytes we could not inflate
		}
		
		count = _strmIn->bytesAvail();
	}

	// dequeue bytes available in output buffer ...
	memcpy(buffer, _strmIn->buffer(), count);
	_strmIn->dequeue(count);

	return count;
}

size_t ZLibIOFilter::write(const char* buffer, size_t count) throw(IO::IOError)
{
	if(!_strmOut)
		_strmOut = new P::IO::ZLibOutputStream(9);

	size_t consumed = _strmOut->deflate(buffer, count);
	flushAvailBytes();

	return consumed;
}

size_t ZLibIOFilter::peek(char* buffer, size_t count) throw(IO::IOError)
{
	return 0;
}

offset_t ZLibIOFilter::seek(offset_t offset, IO::IODevice::SeekMode mode) throw(IO::IOError)
{
	throw IO::IOError(0, "Could not seek on device", P_SOURCEINFO);
	return -1;
}

offset_t ZLibIOFilter::size() const throw(IO::IOError)
{
	//@fixme!!!
	return IOFilter::size(); 
}

void ZLibIOFilter::flushAvailBytes()
{
	size_t avail = _strmOut->bytesAvail();
	if(avail)
		_strmOut->dequeue(IOFilter::write(_strmOut->buffer(), avail));
}

}

}