[Remoting] Updates to RPCMessenger for downstream usage

This patch contains several changes for allowing the RPCMessenger to
more easily integrate downstream in media/remoting.

Bug: b/184683535
Change-Id: I4bb9d088d25a6b9acb827b072e9765812e1f6986
Reviewed-on: https://chromium-review.googlesource.com/c/openscreen/+/3089653
Commit-Queue: Jordan Bayles <jophba@chromium.org>
Reviewed-by: Ryan Keane <rwkeane@google.com>

2 files changed, 19 insertions, 3 deletions

diff --git a/cast/streaming/rpc_messenger.cc b/cast/streaming/rpc_messenger.cc
index 3ae6c548..360b5572 100644
--- a/cast/streaming/rpc_messenger.cc
+++ b/cast/streaming/rpc_messenger.cc
@@ -74,14 +74,17 @@ void RpcMessenger::ProcessMessageFromRemote(const uint8_t* message,
                   << "\"";
     return;
   }
+  ProcessMessageFromRemote(std::move(rpc));
+}
 
-  const auto entry = receive_callbacks_.find(rpc->handle());
+void RpcMessenger::ProcessMessageFromRemote(std::unique_ptr<RpcMessage> message) {
+  const auto entry = receive_callbacks_.find(message->handle());
   if (entry == receive_callbacks_.end()) {
     OSP_VLOG << "Dropping message due to unregistered handle: "
-             << rpc->handle();
+             << message->handle();
     return;
   }
-  entry->second(std::move(rpc));
+  entry->second(std::move(message));
 }
 
 void RpcMessenger::SendMessageToRemote(const RpcMessage& rpc) {
@@ -95,5 +98,9 @@ bool RpcMessenger::IsRegisteredForTesting(RpcMessenger::Handle handle) {
   return receive_callbacks_.find(handle) != receive_callbacks_.end();
 }
 
+WeakPtr<RpcMessenger> RpcMessenger::GetWeakPtr() {
+  return weak_factory_.GetWeakPtr();
+}
+
 }  // namespace cast
 }  // namespace openscreen
diff --git a/cast/streaming/rpc_messenger.h b/cast/streaming/rpc_messenger.h
index c997a7b9..dd1b1932 100644
--- a/cast/streaming/rpc_messenger.h
+++ b/cast/streaming/rpc_messenger.h
@@ -12,6 +12,7 @@
 
 #include "cast/streaming/remoting.pb.h"
 #include "util/flat_map.h"
+#include "util/weak_ptr.h"
 
 namespace openscreen {
 namespace cast {
@@ -61,6 +62,9 @@ class RpcMessenger {
   // deserialization by protobuf.
   void ProcessMessageFromRemote(const uint8_t* message,
                                 std::size_t message_len);
+  // This overload distributes an already-deserialized message to the
+  // registered component.
+  void ProcessMessageFromRemote(std::unique_ptr<RpcMessage> message);
 
   // Executes the |send_message_cb_| using |rpc|.
   void SendMessageToRemote(const RpcMessage& rpc);
@@ -68,6 +72,9 @@ class RpcMessenger {
   // Checks if the handle is registered for receiving messages. Test-only.
   bool IsRegisteredForTesting(Handle handle);
 
+  // Weak pointer creator.
+  WeakPtr<RpcMessenger> GetWeakPtr();
+
   // Consumers of RPCMessenger may set the send message callback post-hoc
   // in order to simulate different scenarios.
   void set_send_message_cb_for_testing(SendMessageCallback cb) {
@@ -94,6 +101,8 @@ class RpcMessenger {
 
   // Callback that is ran to send a serialized message.
   SendMessageCallback send_message_cb_;
+
+  WeakPtrFactory<RpcMessenger> weak_factory_{this};
 };
 
 }  // namespace cast