Encode high codepoints as surrogates to safely transport wchar_t over network

fixes #7643

1 files changed, 35 insertions, 0 deletions

diff --git a/src/unittest/test_connection.cpp b/src/unittest/test_connection.cpp
index c5e4085e1..c3aacc536 100644
--- a/src/unittest/test_connection.cpp
+++ b/src/unittest/test_connection.cpp
@@ -39,6 +39,7 @@ public:
 
 	void runTests(IGameDef *gamedef);
 
+	void testNetworkPacketSerialize();
 	void testHelpers();
 	void testConnectSendReceive();
 };
@@ -47,6 +48,7 @@ static TestConnection g_test_instance;
 
 void TestConnection::runTests(IGameDef *gamedef)
 {
+	TEST(testNetworkPacketSerialize);
 	TEST(testHelpers);
 	TEST(testConnectSendReceive);
 }
@@ -78,6 +80,39 @@ struct Handler : public con::PeerHandler
 	const char *name;
 };
 
+void TestConnection::testNetworkPacketSerialize()
+{
+	const static u8 expected[] = {
+		0x00, 0x7b,
+		0x00, 0x02, 0xd8, 0x42, 0xdf, 0x9a
+	};
+
+	if (sizeof(wchar_t) == 2)
+		warningstream << __func__ << " may fail on this platform." << std::endl;
+
+	{
+		NetworkPacket pkt(123, 0);
+
+		// serializing wide strings should do surrogate encoding, we test that here
+		pkt << std::wstring(L"\U00020b9a");
+
+		SharedBuffer<u8> buf = pkt.oldForgePacket();
+		UASSERTEQ(int, buf.getSize(), sizeof(expected));
+		UASSERT(!memcmp(expected, &buf[0], buf.getSize()));
+	}
+
+	{
+		NetworkPacket pkt;
+		pkt.putRawPacket(expected, sizeof(expected), 0);
+
+		// same for decoding
+		std::wstring pkt_s;
+		pkt >> pkt_s;
+
+		UASSERT(pkt_s == L"\U00020b9a");
+	}
+}
+
 void TestConnection::testHelpers()
 {
 	// Some constants for testing