Method uncompress_data

src/zip_archive.cpp:120–171

datablock zip_archive::uncompress_data(entry const &p_entry)
{
	datablock uncompressed_data(p_entry.m_uncompressed_size);

	if (p_entry.m_offset_to_data == 0)
	{
		uint16_t local_filename_len, local_extra_field_len;

		// go to local header, and skip signature, required version, bit flag, compression
		// method, last mod time & date, crc32, compressed & uncompressed size (all of this
		// data is already present in the central directory)
		m_input.seekg(p_entry.m_offset_to_local_header + 4 + 5*2 + 3*4, std::ios::beg);

		// skip local filename and extra fields
		read_binary(m_input, local_filename_len);
		read_binary(m_input, local_extra_field_len);
		m_input.seekg(local_filename_len + local_extra_field_len, std::ios::cur);

		p_entry.m_offset_to_data = m_input.tellg();
	}
	else
		m_input.seekg(p_entry.m_offset_to_data, std::ios::beg);

	switch (p_entry.m_compression_method)
	{
		case 0: // no compression
		{
			m_input.read(reinterpret_cast < char* > (&uncompressed_data[0]), uncompressed_data.size());
			break;
		}

		case 8: // deflate compression
		{
			datablock compressed_data(p_entry.m_compressed_size);
			m_input.read(reinterpret_cast < char* > (&compressed_data[0]), compressed_data.size());

			if (!inflate_data(compressed_data, uncompressed_data))
			{
				LOG_MSG(error, "could not decompress data - returning empty datablock");
				return datablock();
			}

			break;
		};

		default:
			// should not happen - compression methods other than 0 or 8 are filtered earlier
			assert(0);
	}

	return uncompressed_data;
}


void zip_archive::read_central_directory()