deflatingstream.cpp

This software aims to create an applet and panel tools to manage a wireless interface card, such as

//
// DeflatingStream.cpp
//
// $Id: //poco/Main/Foundation/src/DeflatingStream.cpp#5 $
//
// Copyright (c) 2004, Guenter Obiltschnig/Applied Informatics.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// 3. Redistributions in any form must be accompanied by information on
//    how to obtain complete source code for this software and any
//    accompanying software that uses this software.  The source code
//    must either be included in the distribution or be available for no
//    more than the cost of distribution plus a nominal fee, and must be
//    freely redistributable under reasonable conditions.  For an
//    executable file, complete source code means the source code for all
//    modules it contains.  It does not include source code for modules or
//    files that typically accompany the major components of the operating
//    system on which the executable file runs.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//


#include "Foundation/DeflatingStream.h"
#include "Foundation/Exception.h"


Foundation_BEGIN


DeflatingStreamBuf::DeflatingStreamBuf(std::istream& istr, StreamType type, int level): 
	BufferedStreamBuf(STREAM_BUFFER_SIZE, std::ios::in),
	_pIstr(&istr),
	_pOstr(0),
	_eof(false)
{
	_zstr.zalloc    = Z_NULL;
	_zstr.zfree     = Z_NULL;
	_zstr.opaque    = Z_NULL;
	_zstr.next_in   = 0;
	_zstr.avail_in  = 0;
	_zstr.next_out  = 0;
	_zstr.avail_out = 0;

	int rc = deflateInit2(&_zstr, level, Z_DEFLATED, 15 + (type == STREAM_GZIP ? 16 : 0), 8, Z_DEFAULT_STRATEGY);
	if (rc != Z_OK) throw IOException(zError(rc)); 

	_buffer = new char[DEFLATE_BUFFER_SIZE];
}


DeflatingStreamBuf::DeflatingStreamBuf(std::ostream& ostr, StreamType type, int level): 
	BufferedStreamBuf(STREAM_BUFFER_SIZE, std::ios::out),
	_pIstr(0),
	_pOstr(&ostr),
	_eof(false)
{
	_zstr.zalloc    = Z_NULL;
	_zstr.zfree     = Z_NULL;
	_zstr.opaque    = Z_NULL;
	_zstr.next_in   = 0;
	_zstr.avail_in  = 0;
	_zstr.next_out  = 0;
	_zstr.avail_out = 0;

	int rc = deflateInit2(&_zstr, level, Z_DEFLATED, 15 + (type == STREAM_GZIP ? 16 : 0), 8, Z_DEFAULT_STRATEGY);
	if (rc != Z_OK) throw IOException(zError(rc)); 

	_buffer = new char[DEFLATE_BUFFER_SIZE];
}


DeflatingStreamBuf::~DeflatingStreamBuf()
{
	close();
	delete [] _buffer;
}


int DeflatingStreamBuf::close()
{
	sync();
	if (_pIstr)
	{
		int rc = deflateEnd(&_zstr);
		if (rc != Z_OK) throw IOException(zError(rc));
		_pIstr = 0;
	}
	else if (_pOstr)
	{
		if (_zstr.next_out)
		{
			int rc = deflate(&_zstr, Z_FINISH);
			if (rc != Z_OK && rc != Z_STREAM_END) throw IOException(zError(rc)); 
			_pOstr->write(_buffer, DEFLATE_BUFFER_SIZE - _zstr.avail_out);
			if (!_pOstr->good()) throw IOException(zError(rc)); 
			_zstr.next_out  = (unsigned char*) _buffer;
			_zstr.avail_out = DEFLATE_BUFFER_SIZE;
			while (rc != Z_STREAM_END)
			{
				rc = deflate(&_zstr, Z_FINISH);
				if (rc != Z_OK && rc != Z_STREAM_END) throw IOException(zError(rc)); 
				_pOstr->write(_buffer, DEFLATE_BUFFER_SIZE - _zstr.avail_out);
				if (!_pOstr->good()) throw IOException(zError(rc)); 
				_zstr.next_out  = (unsigned char*) _buffer;
				_zstr.avail_out = DEFLATE_BUFFER_SIZE;
			}
			rc = deflateEnd(&_zstr);
			if (rc != Z_OK) throw IOException(zError(rc));
		}
		_pOstr = 0;
	}
	return 0;
}


int DeflatingStreamBuf::readFromDevice(char* buffer, std::streamsize length)
{
	if (!_pIstr) return 0;
	if (!_zstr.next_in && !_eof)
	{
		int n = 0;
		if (_pIstr->good())
		{
			_pIstr->read(_buffer, DEFLATE_BUFFER_SIZE);
			n = _pIstr->gcount();
		}
		if (n > 0)
		{
			_zstr.next_in  = (unsigned char*) _buffer;
			_zstr.avail_in = n;
		}
		else
		{
			_zstr.next_in  = 0;
			_zstr.avail_in = 0;
			_eof = true;
		}
		_zstr.next_out  = (unsigned char*) buffer;
		_zstr.avail_out = length;
	}
	else if (_zstr.avail_out == 0)
	{
		_zstr.next_out  = (unsigned char*) buffer;
		_zstr.avail_out = length;
	}
	for (;;)
	{
		int rc = deflate(&_zstr, _eof ? Z_FINISH : Z_NO_FLUSH);
		if (_eof && rc == Z_STREAM_END) 
		{
			rc = deflateEnd(&_zstr);
			if (rc != Z_OK) throw IOException(zError(rc));
			_pIstr = 0;
			return length - _zstr.avail_out;
		}
		if (rc != Z_OK) throw IOException(zError(rc)); 
		if (_zstr.avail_out == 0)
		{
			return length;
		}
		if (_zstr.avail_in == 0)
		{
			int n = 0;
			if (_pIstr->good())
			{
				_pIstr->read(_buffer, DEFLATE_BUFFER_SIZE);
				n = _pIstr->gcount();
			}
			if (n > 0)
			{
				_zstr.next_in  = (unsigned char*) _buffer;
				_zstr.avail_in = n;
			}
			else
			{
				_zstr.next_in  = 0;
				_zstr.avail_in = 0;
				_eof = true;
			}
		}
	}
}


int DeflatingStreamBuf::writeToDevice(const char* buffer, std::streamsize length)
{
	if (length == 0 || !_pOstr) return 0;

	_zstr.next_in   = (unsigned char*) buffer;
	_zstr.avail_in  = length;
	_zstr.next_out  = (unsigned char*) _buffer;
	_zstr.avail_out = DEFLATE_BUFFER_SIZE;
	for (;;)
	{
		int rc = deflate(&_zstr, Z_NO_FLUSH);
		if (rc != Z_OK) throw IOException(zError(rc)); 
		if (_zstr.avail_out == 0)
		{
			_pOstr->write(_buffer, DEFLATE_BUFFER_SIZE);
			if (!_pOstr->good()) throw IOException(zError(rc)); 
			_zstr.next_out  = (unsigned char*) _buffer;
			_zstr.avail_out = DEFLATE_BUFFER_SIZE;
		}
		if (_zstr.avail_in == 0)
		{
			_pOstr->write(_buffer, DEFLATE_BUFFER_SIZE - _zstr.avail_out);
			if (!_pOstr->good()) throw IOException(zError(rc)); 
			_zstr.next_out  = (unsigned char*) _buffer;
			_zstr.avail_out = DEFLATE_BUFFER_SIZE;
			break;
		}
	}
	return length;
}


DeflatingIOS::DeflatingIOS(std::ostream& ostr, DeflatingStreamBuf::StreamType type, int level):
	_buf(ostr, type, level)
{
	init(&_buf);
}


DeflatingIOS::DeflatingIOS(std::istream& istr, DeflatingStreamBuf::StreamType type, int level):
	_buf(istr, type, level)
{
	init(&_buf);
}


DeflatingIOS::~DeflatingIOS()
{
}


DeflatingStreamBuf* DeflatingIOS::rdbuf()
{
	return &_buf;
}


DeflatingOutputStream::DeflatingOutputStream(std::ostream& ostr, DeflatingStreamBuf::StreamType type, int level):
	DeflatingIOS(ostr, type, level),
	std::ostream(&_buf)
{
}


DeflatingOutputStream::~DeflatingOutputStream()
{
}


int DeflatingOutputStream::close()
{
	return _buf.close();
}


DeflatingInputStream::DeflatingInputStream(std::istream& istr, DeflatingStreamBuf::StreamType type, int level):
	DeflatingIOS(istr, type, level),
	std::istream(&_buf)
{
}


DeflatingInputStream::~DeflatingInputStream()
{
}


Foundation_END