Method Index

src/IECore/StreamIndexedIO.cpp:1558–1619

///////////////////////////////////////////////

StreamIndexedIO::Index::Index( StreamIndexedIO::StreamFilePtr stream, const CompoundData *options )
	: m_root( nullptr ),
	m_version( g_currentVersion ),
	m_hasChanged( false ),
	m_offset( 0 ),
	m_next( 0 ),
	m_stream( stream ), m_compressionLevel( 0 ),
	m_compressionThreadCount(1),
	m_decompressionThreadCount(1), m_compressor( "lz4" )

{
	m_stringCache.add(IndexedIO::rootName);

	const char *compressionLevelEnvVar = getenv( "IECORE_STREAMINDEXEDIO_COMPRESSION" );
	if ( compressionLevelEnvVar )
	{
		char buffer[1024];
		if ( sscanf( compressionLevelEnvVar, "%s %i %i %i", &buffer[0], &m_compressionLevel, &m_compressionThreadCount, &m_decompressionThreadCount ) == 4 )
		{
			m_compressor = std::string( buffer );
		}
	}

	if ( options )
	{
		if ( const StringData* compressor = options->member<StringData>("compressor", false) )
		{
			m_compressor = compressor->readable();
		}

		if ( const IntData* compressionLevel = options->member<IntData>("compressionLevel", false) )
		{
			m_compressionLevel = compressionLevel->readable();
		}

		if ( const IntData* compressionThreadCount = options->member<IntData>("compressionThreadCount", false) )
		{
			m_compressionThreadCount = compressionThreadCount->readable();
		}

		if ( const IntData* decompressionThreadCount = options->member<IntData>("decompressionThreadCount", false) )
		{
			m_decompressionThreadCount = decompressionThreadCount->readable();
		}

		if ( const UIntData* maxCompressedBlockSize = options->member<UIntData>("maxCompressedBlockSize", false) )
		{
			m_maxCompressedBlockSize = maxCompressedBlockSize->readable();
		}
	}

	// validate our parameters
	m_compressionLevel = std::min( std::max( 0, m_compressionLevel ), 9 ); // todo replace with std::clamp in C++17
	m_compressionThreadCount = std::min( std::max( 1, m_compressionThreadCount ), 32 );
	m_decompressionThreadCount = std::min( std::max( 1, m_decompressionThreadCount ), 32 );

	if ( getCompressionCode( m_compressor ) == -1)
	{