Method readNodeFromSubIndex

src/IECore/StreamIndexedIO.cpp:2642–2705

}

void StreamIndexedIO::Index::readNodeFromSubIndex( DirectoryNode *n )
{
	/// guarantees thread safe access to the file and also to the m_subindex variable
	StreamFile::MutexLock lock( m_stream->mutex() );

	if ( n->subindex() == DirectoryNode::LoadedSubIndex )
	{
		return;
	}

	m_stream->seekg( n->offset(), std::ios::beg );

	uint32_t subindexSize = 0;
	readLittleEndian( *m_stream, subindexSize );

	char *data = m_stream->ioBuffer(subindexSize);
	m_stream->read( data, subindexSize );

	io::filtering_istream indexInStream;

	if (m_version >= 7)
	{
		std::vector<char> decompressedIndex;
		decompress( data, subindexSize, decompressedIndex, 1 );

		MemoryStreamSource source( &decompressedIndex[0], decompressedIndex.size(), false );
		indexInStream.push( source );
		assert( indexInStream.is_complete() );

		uint32_t nodeCount = 0;

		readLittleEndian( indexInStream, nodeCount );

		for( uint32_t i = 0; i < nodeCount; i++ )
		{
			NodeBase *child = m_version >= 6 ? readNode( indexInStream ) : readNodeV5( indexInStream );
			n->registerChild( child );
		}
	}
	else
	{
		MemoryStreamSource source( data, subindexSize, false );

		indexInStream.push( io::gzip_decompressor() );
		indexInStream.push( source );
		assert( indexInStream.is_complete() );

		uint32_t nodeCount = 0;

		readLittleEndian( indexInStream, nodeCount );

		for( uint32_t i = 0; i < nodeCount; i++ )
		{
			NodeBase *child = m_version >= 6 ? readNode( indexInStream ) : readNodeV5( indexInStream );
			n->registerChild( child );
		}
	}