netradiant-custom/plugins/archivezip/zlibstream.h

66 lines
2.0 KiB
C++

/*
Copyright (C) 2001-2006, William Joseph.
All Rights Reserved.
This file is part of GtkRadiant.
GtkRadiant is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
GtkRadiant 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 General Public License
along with GtkRadiant; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#pragma once
#include "zlib.h"
#include "idatastream.h"
#include <vector> // std::size
/// \brief A wrapper around an InputStream of data compressed with the zlib deflate algorithm.
///
/// - Uses z_stream to decompress the data stream on the fly.
/// - Uses a buffer to reduce the number of times the wrapped stream must be read.
class DeflatedInputStream : public InputStream
{
InputStream& m_istream;
z_stream m_zipstream;
unsigned char m_buffer[1024];
public:
DeflatedInputStream( InputStream& istream )
: m_istream( istream ){
m_zipstream.zalloc = 0;
m_zipstream.zfree = 0;
m_zipstream.opaque = 0;
m_zipstream.avail_in = 0;
inflateInit2( &m_zipstream, -MAX_WBITS );
}
~DeflatedInputStream(){
inflateEnd( &m_zipstream );
}
size_type read( byte_type* buffer, size_type length ){
m_zipstream.next_out = buffer;
m_zipstream.avail_out = static_cast<uInt>( length );
while ( m_zipstream.avail_out != 0 )
{
if ( m_zipstream.avail_in == 0 ) {
m_zipstream.next_in = m_buffer;
m_zipstream.avail_in = static_cast<uInt>( m_istream.read( m_buffer, std::size( m_buffer ) ) );
}
if ( inflate( &m_zipstream, Z_SYNC_FLUSH ) != Z_OK ) {
break;
}
}
return length - m_zipstream.avail_out;
}
};