Method GetData

src/engine/shared/datafile.cpp:191–300

	}

	void *GetData(int Index, bool Swap) const
	{
		// Invalid data indices may appear in map items
		if(Index < 0 || Index >= m_Header.m_NumRawData)
		{
			return nullptr;
		}

		// Data already loaded
		if(m_ppDataPtrs[Index] != nullptr)
		{
			return m_ppDataPtrs[Index];
		}

		// Don't try to load the data again if it previously failed
		if(m_pDataSizes[Index] < 0)
		{
			return nullptr;
		}

		const unsigned DataSize = GetFileDataSize(Index);
		if(m_Info.m_pDataSizes != nullptr)
		{
			// v4 has compressed data
			const unsigned OriginalUncompressedSize = m_Info.m_pDataSizes[Index];
			log_trace("datafile", "loading data. index=%d size=%d uncompressed=%d", Index, DataSize, OriginalUncompressedSize);
			if(OriginalUncompressedSize == 0)
			{
				log_error("datafile", "data size invalid. data will be ignored. index=%d size=%d uncompressed=%d", Index, DataSize, OriginalUncompressedSize);
				m_ppDataPtrs[Index] = nullptr;
				m_pDataSizes[Index] = -1;
				return nullptr;
			}

			// read the compressed data
			void *pCompressedData = malloc(DataSize);
			if(pCompressedData == nullptr)
			{
				log_error("datafile", "out of memory. could not allocate memory for compressed data. index=%d size=%d", Index, DataSize);
				m_ppDataPtrs[Index] = nullptr;
				m_pDataSizes[Index] = -1;
				return nullptr;
			}
			unsigned ActualDataSize = 0;
			if(io_seek(m_File, m_DataStartOffset + m_Info.m_pDataOffsets[Index], IOSEEK_START) == 0)
			{
				ActualDataSize = io_read(m_File, pCompressedData, DataSize);
			}
			if(DataSize != ActualDataSize)
			{
				log_error("datafile", "truncation error. could not read all compressed data. index=%d wanted=%d got=%d", Index, DataSize, ActualDataSize);
				free(pCompressedData);
				m_ppDataPtrs[Index] = nullptr;
				m_pDataSizes[Index] = -1;
				return nullptr;
			}

			// decompress the data