Function FindLayer1Start

pcsx2/CDVD/CDVDisoReader.cpp:117–156

}

static void FindLayer1Start()
{
	if (layer1searched)
		return;

	layer1searched = true;

	std::array<u8, CD_FRAMESIZE_RAW> buffer;

	// The ISO9660 primary volume descriptor for layer 0 is located at sector 16
	iso.ReadSync(buffer.data(), 16);
	if (!testForPrimaryVolumeDescriptor(buffer))
	{
		Console.Error("isoFile: Invalid layer0 Primary Volume Descriptor");
		return;
	}

	// The volume space size (sector count) is located at bytes 80-87 - 80-83
	// is the little endian size, 84-87 is the big endian size.
	const int offset = iso.GetBlockOffset();
	uint blockresult = buffer[offset + 80] + (buffer[offset + 81] << 8) + (buffer[offset + 82] << 16) + (buffer[offset + 83] << 24);

	// If the ISO sector count is larger than the volume size, then we should
	// have a dual layer DVD. Layer 1 is on a different volume.
	if (blockresult < iso.GetBlockCount())
	{
		// The layer 1 start LSN contains the primary volume descriptor for layer 1.
		// The check might be a bit unnecessary though.
		if (iso.ReadSync(buffer.data(), blockresult) == -1)
			return;

		if (!testForPrimaryVolumeDescriptor(buffer))
		{
			Console.Error("isoFile: Invalid layer1 Primary Volume Descriptor");
			return;
		}
		layer1start = blockresult;
		Console.WriteLn(Color_Blue, "isoFile: second layer found at sector 0x%08x", layer1start);
	}
}

// Should return 0 if no error occurred, or -1 if layer detection FAILED.
static s32 ISOgetDualInfo(s32* dualType, u32* _layer1start)