Driver version support

.gitignore

@@ -29,3 +29,4 @@ vcpkg_installed/
 # Project-specific
 build/*
 out/
+/.vscode

README.md

@@ -46,8 +46,18 @@ Run the bootstrap script to build vcpkg binary `.\vcpkg\bootstrap-vcpkg.bat` or
 
 After installing vcpkg if you're on Windows, you need to run `vcpkg integrate install` command from the vcpkg folder to integrate it for VSCode.
 
-For other systems and IDEs instructions are not available as of now, contributions are welcome.
+Then you will need to run `cmake -B build` once to setup CMake.
+
+Finally, everytime you want to build binaries, just run `cmake --build build --config Release`. The newly built binary will be in the build/release directory.
+
+For other systems and IDEs, instructions are not available as of now, but contributions are welcome.
 
 ### Updating vcpkg packages
 
-To update vcpkg packages set the vcpkg registry submodule to a newer commit and rerun the bootstrap script.
+To update vcpkg packages set the vcpkg registry submodule to a newer commit and rerun the bootstrap script.
+
+### Updating protobuf messages
+
+You can modify the protobuf messages for communication between the server and this driver in [src\bridge\ProtobufMessages.proto](src\bridge\ProtobufMessages.proto). Please update PROTOCOL_VERSION in [src\bridge\BridgeClient.hpp](src\bridge\BridgeClient.hpp)
+
+To update the protobuf messages on the server, you will need to install [protoc](https://protobuf.dev/installation/) (we use version 4.31.1), then make sure that your SlimeVR-Server and SlimeVR-OpenVR-Driver repositories are in the same parent directory and run `protobuf_update.bat` located at `SlimeVR-Server\server\desktop`

src/bridge/BridgeClient.cpp

@@ -40,6 +40,7 @@ void BridgeClient::CreateConnection() {
         logger_->Log("[{}] connected", path);
         connected_ = true;
         last_error_ = std::nullopt;
+        SendVersion();
     });
     connection_handle_->on<uvw::end_event>([this, path](const uvw::end_event&, uvw::pipe_handle&) {
         logger_->Log("[{}] disconnected", path);
@@ -79,3 +80,12 @@ void BridgeClient::CloseConnectionHandles() {
     if (reconnect_timeout_) reconnect_timeout_->close();
     connected_ = false;
 }
+
+void BridgeClient::SendVersion() {
+    messages::ProtobufMessage* message = google::protobuf::Arena::CreateMessage<messages::ProtobufMessage>(&arena_);
+    messages::Version* version = google::protobuf::Arena::CreateMessage<messages::Version>(&arena_);
+    message->set_allocated_version(version);
+    version->set_protocol_version(PROTOCOL_VERSION);
+    SendBridgeMessage(*message);
+    arena_.Reset();
+}

src/bridge/BridgeClient.hpp

@@ -28,6 +28,8 @@
 
 #include "BridgeTransport.hpp"
 
+#define PROTOCOL_VERSION 1
+
 /**
  * @brief Client implementation for communication with SlimeVR Server using pipes or unix sockets.
  * 
@@ -49,8 +51,11 @@ class BridgeClient: public BridgeTransport {
     void ResetConnection() override;
     void CloseConnectionHandles() override;
     void Reconnect();
+    void SendVersion();
 
     std::optional<std::string> last_error_;
     std::optional<std::string> last_path_;
     std::shared_ptr<uvw::timer_handle> reconnect_timeout_;
+
+    google::protobuf::Arena arena_;
 };

src/bridge/BridgeTransport.cpp

@@ -81,10 +81,10 @@ void BridgeTransport::OnRecv(const uvw::data_event& event) {
         char len_buf[4];
         recv_buf_.Peek(len_buf, 4);
         uint32_t size = 0;
-        size |= static_cast<uint32_t>(static_cast<uint8_t>(len_buf[0])) << 0;
-        size |= static_cast<uint32_t>(static_cast<uint8_t>(len_buf[1])) << 8;
-        size |= static_cast<uint32_t>(static_cast<uint8_t>(len_buf[2])) << 16;
-        size |= static_cast<uint32_t>(static_cast<uint8_t>(len_buf[3])) << 24;
+        size = static_cast<uint32_t>(static_cast<uint8_t>(len_buf[0])) |
+              (static_cast<uint32_t>(static_cast<uint8_t>(len_buf[1])) << 8) |
+              (static_cast<uint32_t>(static_cast<uint8_t>(len_buf[2])) << 16) |
+              (static_cast<uint32_t>(static_cast<uint8_t>(len_buf[3])) << 24);
 
         if (size > VRBRIDGE_MAX_MESSAGE_SIZE) {
             logger_->Log(

src/bridge/ProtobufMessages.proto

@@ -47,13 +47,17 @@ package messages;
  * recieve messages this frame.
  */
 
-option java_package = "dev.slimevr.bridge";
+option java_package = "dev.slimevr.desktop.platform";
 option java_outer_classname = "ProtobufMessages";
 option optimize_for = LITE_RUNTIME;
 
 message PingPong {
 }
 
+message Version {
+  int32 protocol_version = 1;
+}
+
 message Position {
     int32 tracker_id = 1;
     optional float x = 2;
@@ -117,5 +121,6 @@ message ProtobufMessage {
         TrackerAdded tracker_added = 3;
         TrackerStatus tracker_status = 4;
         Battery battery = 5;
+        Version version = 6;
     }
 }

test/TestBridgeClientMock.cpp

@@ -74,7 +74,10 @@ TEST_CASE("IO with a mock server", "[Bridge]") {
                     tracker_position->set_qw(0);
                     server_mock->SendBridgeMessage(*server_message);
                 }
-            } else {
+            } else if(message.has_version()) {
+                TestLogVersion(logger, message);
+            }
+            else {
                 invalid_messages++;
             }
 

test/common/TestBridgeClient.cpp

@@ -25,6 +25,12 @@ void TestLogTrackerStatus(std::shared_ptr<Logger> logger, const messages::Protob
     }
 }
 
+void TestLogVersion(std::shared_ptr<Logger> logger, const messages::ProtobufMessage& message) {
+    if (!message.has_version()) return;
+    messages::Version version = message.version();
+    logger->Log("protocol version {}", version.protocol_version());
+}
+
 void TestBridgeClient() {
     using namespace std::chrono;
 

test/common/TestBridgeClient.hpp

@@ -8,4 +8,5 @@
 
 void TestLogTrackerAdded(std::shared_ptr<Logger> logger, const messages::ProtobufMessage& message);
 void TestLogTrackerStatus(std::shared_ptr<Logger> logger, const messages::ProtobufMessage& message);
+void TestLogVersion(std::shared_ptr<Logger> logger, const messages::ProtobufMessage& message);
 void TestBridgeClient();