Allow retriving N bytes of data without coping using variadic ByteView::Read

Src/Common/MWR/C3/Interfaces/Connectors/TeamServer.cpp

@@ -385,7 +385,7 @@ bool MWR::C3::Interfaces::Connectors::TeamServer::Connection::SecondThreadStarte
 
 MWR::ByteVector MWR::C3::Interfaces::Connectors::TeamServer::PeripheralCreationCommand(ByteView connectionId, ByteView data, bool isX64)
 {
-	auto [pipeName, maxConnectionTrials, delayBetweenConnectionTrials/*, payload*/] = data.Read<std::string, uint16_t, uint16_t/*, ByteVector*/>();
+	auto [pipeName, maxConnectionTrials, delayBetweenConnectionTrials/*, payload*/] = data.Read<std::string, uint16_t, uint16_t/*, ByteView*/>();
 
 	// custom payload is removed from release.
 	//if (!payload.empty())

Src/Common/MWR/C3/Interfaces/Peripherals/Beacon.cpp

@@ -4,7 +4,7 @@
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 MWR::C3::Interfaces::Peripherals::Beacon::Beacon(ByteView arguments)
 {
-	auto [pipeName, maxConnectionTrials, delayBetweenConnectionTrials, payload] = arguments.Read<std::string, uint16_t, uint16_t, ByteVector>();
+	auto [pipeName, maxConnectionTrials, delayBetweenConnectionTrials, payload] = arguments.Read<std::string, uint16_t, uint16_t, ByteView>();
 
 	// Arguments validation.
 	if (payload.empty())

Src/Common/MWR/CppTools/ByteView.h

@@ -40,6 +40,10 @@ namespace MWR
 	/// @returns std::vector<std::string> tokenized string.
 	std::vector<std::string> SplitAndCopy(std::string_view stringToBeSplitted, std::string_view delimiter);
 
+	/// Idiom for detecting ByteView::Get.
+	template <typename X>
+	constexpr bool IsGetter = false;
+
 	/// Non owning container.
 	class ByteView : std::basic_string_view<ByteVector::value_type>
 	{
@@ -136,6 +140,7 @@ namespace MWR
 		using Super::npos;
 		using Super::value_type;
 
+
 		/// @returns ByteVector. Owning container with the read bytes.
 		/// @param byteCount. How many bytes should be read.
 		/// @remarks Read is not compatible with Read<ByteVector>.
@@ -187,7 +192,7 @@ namespace MWR
 		/// Read bytes and remove them from ByteView.
 		/// @returns ByteArray. Owning container with the read bytes.
 		/// @throws std::out_of_range. If ByteView is too short to hold size of object to return.
-		template<typename T, typename std::enable_if_t<IsByteArray<T>, int> = 0>
+		template<typename T>
 		std::enable_if_t<IsByteArray<T>, T> Read()
 		{
 			if (std::tuple_size<typename T>::value > size())
@@ -223,6 +228,35 @@ namespace MWR
 			return TupleGenerator<T>::Generate(*this);
 		}
 
+		/// Class allowing reading N bytes without coping data like in ByeView::Read<ByteArray<N>> or ByteView::Reed(size_t).
+		template <size_t N>
+		class Get
+		{
+		public:
+			/// Define size marker.
+			static constexpr size_t size = N;
+			static constexpr size_t Size = size;
+
+		private:
+			/// Private constructor.
+			/// This class should never be instantiated.
+			Get() = default;
+		};
+
+		/// Read bytes and remove them from ByteView.
+		/// @returns ByteView. Non owning container with the read bytes.
+		/// @throws std::out_of_range. If ByteView is too short to hold size of object to return.
+		template<typename T>
+		std::enable_if_t<IsGetter<T>, ByteView> Read()
+		{
+			if (T::Size > size())
+				throw std::out_of_range{ OBF(": Cannot read data from ByteView") };
+
+			auto retVal = SubString(0, T::Size);
+			remove_prefix(T::Size);
+			return retVal;
+		}
+
 		/// Read tuple and remove bytes from ByteView.
 		/// @tparam T. Parameter pack of types to be stored in tuple. Must consist more then one type. Each of types must be parsable by Reed template for one type.
 		/// @returns std::tuple. Tuple will store types provided in parameter pack.
@@ -273,7 +307,7 @@ namespace MWR
 			{
 				auto current = std::make_tuple(self.Read<T>());
 				auto rest = VariadicTupleGenerator<Rest...>::Generate(self);
-				return std::tuple_cat(current, rest);
+				return std::tuple_cat(std::move(current), std::move(rest));
 			}
 		};
 
@@ -325,6 +359,14 @@ namespace MWR
 		};
 	};
 
+	/// Specialization of idiom for detecting ByteView::Get.
+	template<size_t N>
+	constexpr bool IsGetter<ByteView::Get<N>> = true;
+
+	/// Alias for simpler use of ByteView::Get.
+	template<size_t N>
+	using Bytes = ByteView::Get<N>;
+
 	namespace Literals
 	{
 		/// Create ByteView with syntax ""_bvec

Src/Core/GateRelay.cpp

@@ -47,7 +47,7 @@ void MWR::C3::Core::GateRelay::OnProtocolS2G(ByteView packet0, std::shared_ptr<D
 	try
 	{
 		auto decrypted = MWR::Crypto::DecryptFromAnonymous(packet0.SubString(1), m_AuthenticationKey, m_DecryptionKey);
-		auto [procedure, rid, timestamp] = ByteView{ decrypted }.Read<ProceduresUnderlyingType, ByteArray<RouteId::BinarySize>, int32_t>();
+		auto [procedure, rid, timestamp] = ByteView{ decrypted }.Read<ProceduresUnderlyingType, Bytes<RouteId::BinarySize>, int32_t>();
 		if (!m_Profiler->Get().m_Gateway.ConnectionExist(RouteId::FromByteView(rid).GetAgentId()))
 			throw std::runtime_error{ "S2G packet received from not connected source." };
 
@@ -274,10 +274,10 @@ void MWR::C3::Core::GateRelay::On(ProceduresN2N::InitializeRouteQuery&& query)
 	auto readView = ByteView{ decryptedPacket };
 	auto newRelayBuildId = BuildId{ readView.Read<BuildId::UnderlyingIntegerType>() };
 	// todo prepending fixed-size key with 4 byte length is unnecessary, (remember to change writing, not only reading)
-	auto newRelayPublicKey = Crypto::PublicKey{ readView.Read<ByteVector>() };
+	auto newRelayPublicKey = Crypto::PublicKey{ readView.Read<ByteView>() };
 	auto hash = readView.Read<HashT>();
 	auto lastSeen = readView.Read<int32_t>();
-	HostInfo hostInfo(ByteView{ readView.Read<ByteVector>() });
+	HostInfo hostInfo(readView.Read<ByteView>());
 
 	auto receivedFrom = query.GetSenderChannel().lock();
 	if (!receivedFrom)
@@ -299,17 +299,17 @@ void MWR::C3::Core::GateRelay::On(ProceduresS2G::InitializeRouteQuery&& query)
 	auto readView = ByteView{ decryptedPacket };
 
 	// part of message created by parent Node
-	auto [procedureID, parentRid, timestamp, childRid, childSideDid] = readView.Read<ProceduresUnderlyingType, ByteArray<RouteId::BinarySize>, int32_t, ByteArray<RouteId::BinarySize>, ByteArray<DeviceId::BinarySize>>();
+	auto [procedureID, parentRid, timestamp, childRid, childSideDid] = readView.Read<ProceduresUnderlyingType, Bytes<RouteId::BinarySize>, int32_t, Bytes<RouteId::BinarySize>, Bytes<DeviceId::BinarySize>>();
 
 	// part of message from new relay. encrypted once again because it was blob for parent relay.
 	auto childPacket = Crypto::DecryptFromAnonymous(readView, m_AuthenticationKey, m_DecryptionKey);
 	readView = ByteView{ childPacket };
 
 	auto newRelayBuildId = BuildId{ readView.Read<BuildId::UnderlyingIntegerType>() }; // todo blocking
-	auto newRelayPublicKey = Crypto::PublicKey{ readView.Read<ByteVector>() };
+	auto newRelayPublicKey = Crypto::PublicKey{ readView.Read<ByteView>() };
 	auto hash = readView.Read<HashT>();
 	auto lastSeen = readView.Read<int32_t>();
-	HostInfo hostInfo(ByteView{ readView.Read<ByteVector>() });
+	HostInfo hostInfo(readView.Read<ByteView>());
 
 	auto receivedFrom = query.GetSenderChannel().lock();
 	if (!receivedFrom)
@@ -337,9 +337,9 @@ void MWR::C3::Core::GateRelay::On(ProceduresS2G::DeliverToBinder query)
 	auto readView = ByteView{ decryptedPacket };
 
 	auto unusedProtocolId = readView.Read<int8_t>();
-	auto senderRid = RouteId::FromByteView(readView.Read<ByteArray<RouteId::BinarySize>>());
+	auto senderRid = RouteId::FromByteView(readView.Read<Bytes<RouteId::BinarySize>>());
 	auto timestamp = readView.Read<int32_t>();
-	auto deviceId = readView.Read<ByteArray<DeviceId::BinarySize>>();
+	auto deviceId = readView.Read<Bytes<DeviceId::BinarySize>>();
 	auto connectorHash = readView.Read<HashT>();
 
 	auto connector = m_Connectors.Find([&](auto const& e){ return e->GetNameHash() == connectorHash; });
@@ -372,7 +372,7 @@ void MWR::C3::Core::GateRelay::On(ProceduresS2G::AddDeviceResponse response)
 {
 	auto decryptedPacket = response.GetQueryPacket(m_AuthenticationKey, m_DecryptionKey);
 	auto readView = ByteView{ decryptedPacket };
-	auto [unsusedProcedureNo, unusedSenderRouteId, timestamp, deviceId, deviceTypeHash, flags] = readView.Read<ProceduresUnderlyingType, ByteArray<RouteId::BinarySize>, int32_t, DeviceId::UnderlyingIntegerType, HashT, std::uint8_t>();
+	auto [unsusedProcedureNo, unusedSenderRouteId, timestamp, deviceId, deviceTypeHash, flags] = readView.Read<ProceduresUnderlyingType, Bytes<RouteId::BinarySize>, int32_t, DeviceId::UnderlyingIntegerType, HashT, std::uint8_t>();
 	bool isChannel = flags & 1;
 	bool isNegotiationChannel = flags & (1 << 1);
 
@@ -393,7 +393,7 @@ void MWR::C3::Core::GateRelay::On(ProceduresS2G::AddDeviceResponse response)
 void MWR::C3::Core::GateRelay::On(ProceduresN2N::ChannelIdExchangeStep1 query)
 {
 	auto readView = ByteView{ query.GetQueryPacket() };
-	auto newOutputId = readView.Read<ByteVector>();
+	auto newOutputId = readView.Read<ByteView>();
 
 	auto newInputId = MWR::Utils::GenerateRandomString(newOutputId.size());
 	auto sender = query.GetSenderChannel().lock();
@@ -426,7 +426,7 @@ void MWR::C3::Core::GateRelay::On(ProceduresS2G::NewNegotiatedChannelNotificatio
 {
 	auto decryptedPacket = query.GetQueryPacket(m_AuthenticationKey, m_DecryptionKey);
 	auto readView = ByteView{ decryptedPacket };
-	auto [unsusedProcedureNo, unusedSenderRouteId, timestamp, newDeviceId, negotiatorId, inId, outId] = readView.Read<ProceduresUnderlyingType, ByteArray<RouteId::BinarySize>, int32_t, DeviceId::UnderlyingIntegerType, DeviceId::UnderlyingIntegerType, std::string, std::string>();
+	auto [unsusedProcedureNo, unusedSenderRouteId, timestamp, newDeviceId, negotiatorId, inId, outId] = readView.Read<ProceduresUnderlyingType, Bytes<RouteId::BinarySize>, int32_t, DeviceId::UnderlyingIntegerType, DeviceId::UnderlyingIntegerType, std::string, std::string>();
 
 	auto agent = m_Profiler->Get().m_Gateway.m_Agents.Find(query.GetSenderRouteId().GetAgentId());
 	if (!agent)
@@ -448,7 +448,7 @@ void MWR::C3::Core::GateRelay::On(ProceduresS2G::Notification query)
 {
 	auto decryptedPacket = query.GetQueryPacket(m_AuthenticationKey, m_DecryptionKey);
 	auto readView = ByteView{ decryptedPacket };
-	auto [unsusedProcedureNo, unusedSenderRouteId, timestamp, blob] = readView.Read<ProceduresUnderlyingType, ByteArray<RouteId::BinarySize>, int32_t, ByteVector>();
+	auto [unsusedProcedureNo, unusedSenderRouteId, timestamp, blob] = readView.Read<ProceduresUnderlyingType, Bytes<RouteId::BinarySize>, int32_t, ByteView>();
 	// blob has not defined structure. Currently Notification is used as ping response.
 
 	auto agent = m_Profiler->Get().m_Gateway.m_Agents.Find(query.GetSenderRouteId().GetAgentId());

Src/Core/NodeRelay.cpp

@@ -247,7 +247,7 @@ void MWR::C3::Core::NodeRelay::On(ProceduresG2X::RunCommandOnAgentQuery query)
 void MWR::C3::Core::NodeRelay::On(ProceduresG2X::AddRoute query)
 {
 	auto recipient = query.GetRecipientRouteId();
-	auto [newRouteBA, directionDidBA] = ByteView{ query.GetPacketBody() }.Read<ByteArray<RouteId::BinarySize>, ByteArray<DeviceId::BinarySize>>();
+	auto [newRouteBA, directionDidBA] = ByteView{ query.GetPacketBody() }.Read<Bytes<RouteId::BinarySize>, Bytes<DeviceId::BinarySize>>();
 	auto newRoute = RouteId::FromByteView(newRouteBA);
 	auto directionDid = DeviceId(directionDidBA);
 	std::shared_ptr<DeviceBridge> bridge;
@@ -301,7 +301,7 @@ void MWR::C3::Core::NodeRelay::On(ProceduresG2X::DeliverToBinder query)
 void MWR::C3::Core::NodeRelay::On(ProceduresN2N::ChannelIdExchangeStep1 query)
 {
 	auto readView = ByteView{ query.GetQueryPacket() };
-	auto newOutputId = readView.Read<ByteVector>();
+	auto newOutputId = readView.Read<ByteView>();
 
 	auto newInputId = MWR::Utils::GenerateRandomString(newOutputId.size());
 	auto sender = query.GetSenderChannel().lock();
@@ -324,7 +324,7 @@ void MWR::C3::Core::NodeRelay::On(ProceduresN2N::ChannelIdExchangeStep1 query)
 void MWR::C3::Core::NodeRelay::On(ProceduresN2N::ChannelIdExchangeStep2 query)
 {
 	auto readView = ByteView{ query.GetQueryPacket() };
-	auto newOutputId = readView.Read<ByteVector>();
+	auto newOutputId = readView.Read<ByteView>();
 
 	auto sender = query.GetSenderChannel().lock();
 
@@ -334,7 +334,7 @@ void MWR::C3::Core::NodeRelay::On(ProceduresN2N::ChannelIdExchangeStep2 query)
 
 	ByteVector args = sender->GetChannelParameters();
 	auto hash = sender->GetTypeNameHash();
-	auto newInputId = ByteVector{ sender->GetInputId() };
+	auto newInputId = sender->GetInputId() ;
 	DetachDevice(sender->GetDid());
 	sender.reset();
 	// Don't use sender below;

Src/Core/Relay.cpp

@@ -41,7 +41,7 @@ std::shared_ptr<MWR::C3::Core::DeviceBridge> MWR::C3::Core::Relay::CreateAndAtta
 		if (isNegotiationChannel)
 		{
 			auto readView = commandLine;
-			auto negotiationId = readView.Read<ByteVector>();
+			auto negotiationId = readView.Read<ByteView>();
 			helper.reserve(commandLine.size() + negotiationId.size() + sizeof(std::uint32_t));
 			auto generatedId = MWR::Utils::GenerateRandomString(negotiationId.size());
 			if (negotiationClient)