5 files changed, 29 insertions, 0 deletions
diff --git a/include/grpc++/completion_queue.h b/include/grpc++/completion_queue.h
index 0523ab6a0e..2f30211145 100644
--- a/include/grpc++/completion_queue.h
+++ b/include/grpc++/completion_queue.h
@@ -63,6 +63,7 @@ template <class ServiceType, class RequestType, class ResponseType>
 class ServerStreamingHandler;
 template <class ServiceType, class RequestType, class ResponseType>
 class BidiStreamingHandler;
+class UnknownMethodHandler;
 
 class ChannelInterface;
 class ClientContext;
@@ -138,6 +139,7 @@ class CompletionQueue : public GrpcLibrary {
   friend class ServerStreamingHandler;
   template <class ServiceType, class RequestType, class ResponseType>
   friend class BidiStreamingHandler;
+  friend class UnknownMethodHandler;
   friend class ::grpc::Server;
   friend class ::grpc::ServerContext;
   template <class InputMessage, class OutputMessage>
diff --git a/include/grpc++/impl/call.h b/include/grpc++/impl/call.h
index 1fa4490779..d49102fa3e 100644
--- a/include/grpc++/impl/call.h
+++ b/include/grpc++/impl/call.h
@@ -173,6 +173,7 @@ class CallOpSendInitialMetadata {
     grpc_op* op = &ops[(*nops)++];
     op->op = GRPC_OP_SEND_INITIAL_METADATA;
     op->flags = 0;
+    op->reserved = NULL;
     op->data.send_initial_metadata.count = initial_metadata_count_;
     op->data.send_initial_metadata.metadata = initial_metadata_;
   }
@@ -206,6 +207,7 @@ class CallOpSendMessage {
     grpc_op* op = &ops[(*nops)++];
     op->op = GRPC_OP_SEND_MESSAGE;
     op->flags = write_options_.flags();
+    op->reserved = NULL;
     op->data.send_message = send_buf_;
     // Flags are per-message: clear them after use.
     write_options_.Clear();
@@ -248,6 +250,7 @@ class CallOpRecvMessage {
     grpc_op* op = &ops[(*nops)++];
     op->op = GRPC_OP_RECV_MESSAGE;
     op->flags = 0;
+    op->reserved = NULL;
     op->data.recv_message = &recv_buf_;
   }
 
@@ -313,6 +316,7 @@ class CallOpGenericRecvMessage {
     grpc_op* op = &ops[(*nops)++];
     op->op = GRPC_OP_RECV_MESSAGE;
     op->flags = 0;
+    op->reserved = NULL;
     op->data.recv_message = &recv_buf_;
   }
 
@@ -350,6 +354,7 @@ class CallOpClientSendClose {
     grpc_op* op = &ops[(*nops)++];
     op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
     op->flags = 0;
+    op->reserved = NULL;
   }
   void FinishOp(bool* status, int max_message_size) { send_ = false; }
 
@@ -383,6 +388,7 @@ class CallOpServerSendStatus {
     op->data.send_status_from_server.status_details =
         send_status_details_.empty() ? nullptr : send_status_details_.c_str();
     op->flags = 0;
+    op->reserved = NULL;
   }
 
   void FinishOp(bool* status, int max_message_size) {
@@ -416,6 +422,7 @@ class CallOpRecvInitialMetadata {
     op->op = GRPC_OP_RECV_INITIAL_METADATA;
     op->data.recv_initial_metadata = &recv_initial_metadata_arr_;
     op->flags = 0;
+    op->reserved = NULL;
   }
   void FinishOp(bool* status, int max_message_size) {
     if (recv_initial_metadata_ == nullptr) return;
@@ -453,6 +460,7 @@ class CallOpClientRecvStatus {
     op->data.recv_status_on_client.status_details_capacity =
         &status_details_capacity_;
     op->flags = 0;
+    op->reserved = NULL;
   }
 
   void FinishOp(bool* status, int max_message_size) {
diff --git a/include/grpc++/impl/rpc_service_method.h b/include/grpc++/impl/rpc_service_method.h
index 3cfbef7806..925801e1ce 100644
--- a/include/grpc++/impl/rpc_service_method.h
+++ b/include/grpc++/impl/rpc_service_method.h
@@ -208,6 +208,21 @@ class BidiStreamingHandler : public MethodHandler {
   ServiceType* service_;
 };
 
+// Handle unknown method by returning UNIMPLEMENTED error.
+class UnknownMethodHandler : public MethodHandler {
+ public:
+  void RunHandler(const HandlerParameter& param) GRPC_FINAL {
+    Status status(StatusCode::UNIMPLEMENTED, "");
+    CallOpSet<CallOpSendInitialMetadata, CallOpServerSendStatus> ops;
+    if (!param.server_context->sent_initial_metadata_) {
+      ops.SendInitialMetadata(param.server_context->initial_metadata_);
+    }
+    ops.ServerSendStatus(param.server_context->trailing_metadata_, status);
+    param.call->PerformOps(&ops);
+    param.call->cq()->Pluck(&ops);
+  }
+};
+
 // Server side rpc method class
 class RpcServiceMethod : public RpcMethod {
  public:
diff --git a/include/grpc++/server.h b/include/grpc++/server.h
index 94ee0b6a4a..8755b4b445 100644
--- a/include/grpc++/server.h
+++ b/include/grpc++/server.h
@@ -228,6 +228,8 @@ class Server GRPC_FINAL : public GrpcLibrary, private CallHook {
   grpc::condition_variable callback_cv_;
 
   std::list<SyncRequest>* sync_methods_;
+  std::unique_ptr<RpcServiceMethod> unknown_method_;
+  bool has_generic_service_;
 
   // Pointer to the c grpc server.
   grpc_server* const server_;
diff --git a/include/grpc++/server_context.h b/include/grpc++/server_context.h
index 4f7fc54ef1..8262dee654 100644
--- a/include/grpc++/server_context.h
+++ b/include/grpc++/server_context.h
@@ -73,6 +73,7 @@ template <class ServiceType, class RequestType, class ResponseType>
 class ServerStreamingHandler;
 template <class ServiceType, class RequestType, class ResponseType>
 class BidiStreamingHandler;
+class UnknownMethodHandler;
 
 class Call;
 class CallOpBuffer;
@@ -159,6 +160,7 @@ class ServerContext {
   friend class ServerStreamingHandler;
   template <class ServiceType, class RequestType, class ResponseType>
   friend class BidiStreamingHandler;
+  friend class UnknownMethodHandler;
   friend class ::grpc::ClientContext;
 
   // Prevent copying.