Use Chromium BUILD to approximate Blimp protocol version, and check it.

blimp/net/blimp_connection.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "blimp/net/blimp_connection.h"
 
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 87 matching lines @@
   net::CompletionCallback process_callback =
       base::ResetAndReturn(&pending_process_msg_callback_);
 
   if (result != net::OK) {
     error_observer_->OnConnectionError(result);
   }
 
   process_callback.Run(result);
 }
 
+// MessageProcessor filter used to route EndConnection messages through to
+// OnConnectionError notifications on the owning BlimpConnection.
+class BlimpConnection::EndConnectionFilter : public BlimpMessageProcessor {
+ public:
+  explicit EndConnectionFilter(BlimpConnection* connection);
+
+  void set_message_handler(BlimpMessageProcessor* message_handler) {
+    message_handler_ = message_handler;
+  }
+
+  // BlimpMessageProcessor implementation.
+  void ProcessMessage(std::unique_ptr<BlimpMessage> message,
+                      const net::CompletionCallback& callback) override;
+
+ private:
+  // Owning BlimpConnection, on which to call OnConnectionError.
+  BlimpConnection* connection_;
+
+  // Caller-provided message handler to forward non-EndConnection messages to.
+  BlimpMessageProcessor* message_handler_;
+
+  DISALLOW_COPY_AND_ASSIGN(EndConnectionFilter);
+};
+
+BlimpConnection::EndConnectionFilter::EndConnectionFilter(
+    BlimpConnection* connection)
+    : connection_(connection), message_handler_(nullptr) {}
+
+void BlimpConnection::EndConnectionFilter::ProcessMessage(
+    std::unique_ptr<BlimpMessage> message,
+    const net::CompletionCallback& callback) {
+  if (message->has_protocol_control() &&
+      message->protocol_control().has_end_connection()) {
+    // Report the EndConnection reason to connection error observers.
+    connection_->OnConnectionError(
+        message->protocol_control().end_connection().reason());
+
+    // Caller must ensure |callback| safe to call after OnConnectionError.
+    callback.Run(message->protocol_control().end_connection().reason());
+    return;
+  }
+
+  message_handler_->ProcessMessage(std::move(message), callback);
+}
+
 BlimpConnection::BlimpConnection(std::unique_ptr<PacketReader> reader,
                                  std::unique_ptr<PacketWriter> writer)
     : reader_(std::move(reader)),
       message_pump_(new BlimpMessagePump(reader_.get())),
       writer_(std::move(writer)),
-      outgoing_msg_processor_(new BlimpMessageSender(writer_.get())) {
+      outgoing_msg_processor_(new BlimpMessageSender(writer_.get())),
+      end_connection_filter_(new EndConnectionFilter(this)) {
   DCHECK(writer_);
   DCHECK(reader_);
 
   message_pump_->set_error_observer(this);
   outgoing_msg_processor_->set_error_observer(this);
 }
 
 BlimpConnection::BlimpConnection() {}
 
 BlimpConnection::~BlimpConnection() {
   VLOG(1) << "BlimpConnection destroyed.";
 }
 
 void BlimpConnection::AddConnectionErrorObserver(
     ConnectionErrorObserver* observer) {
   error_observers_.AddObserver(observer);
 }
 
 void BlimpConnection::RemoveConnectionErrorObserver(
     ConnectionErrorObserver* observer) {
   error_observers_.RemoveObserver(observer);
 }
 
 void BlimpConnection::SetIncomingMessageProcessor(
     BlimpMessageProcessor* processor) {
-  message_pump_->SetMessageProcessor(processor);
+  end_connection_filter_->set_message_handler(processor);
+  message_pump_->SetMessageProcessor(processor ? end_connection_filter_.get()
+                                               : nullptr);
 }
 
 BlimpMessageProcessor* BlimpConnection::GetOutgoingMessageProcessor() {
   return outgoing_msg_processor_.get();
 }
 
 void BlimpConnection::OnConnectionError(int error) {
   VLOG(1) << "OnConnectionError, error=" << error;
 
   // Propagate the error to all observers.
   FOR_EACH_OBSERVER(ConnectionErrorObserver, error_observers_,
                     OnConnectionError(error));
 }
 
 }  // namespace blimp