Add source code for ctrtool

ctrtool/deps/libtoolchain/src/io/StreamUtil.cpp

@@ -0,0 +1,22 @@
+#include <tc/io/StreamUtil.h>
+
+int64_t tc::io::StreamUtil::getSeekResult(int64_t offset, tc::io::SeekOrigin origin, int64_t current_position, int64_t stream_length)
+{
+	int64_t new_pos = 0;
+	switch (origin)
+	{
+		case (SeekOrigin::Begin):
+			new_pos = offset;
+			break;
+		case (SeekOrigin::Current):
+			new_pos = current_position + offset;
+			break;
+		case (SeekOrigin::End):
+			new_pos = stream_length + offset;
+			break;
+		default:
+			throw tc::ArgumentOutOfRangeException("Illegal value for origin.");
+	}
+
+	return new_pos;
+}