Merge github.com:grpc/grpc into cpparena

8 files changed, 60 insertions, 15 deletions

diff --git a/include/grpc++/impl/codegen/client_unary_call.h b/include/grpc++/impl/codegen/client_unary_call.h
index 201e52ae07..a5a4f3d739 100644
--- a/include/grpc++/impl/codegen/client_unary_call.h
+++ b/include/grpc++/impl/codegen/client_unary_call.h
@@ -52,7 +52,7 @@ template <class InputMessage, class OutputMessage>
 Status BlockingUnaryCall(ChannelInterface* channel, const RpcMethod& method,
                          ClientContext* context, const InputMessage& request,
                          OutputMessage* result) {
-  CompletionQueue cq;
+  CompletionQueue cq(true);  // Pluckable completion queue
   Call call(channel->CreateCall(method, context, &cq));
   CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
             CallOpRecvInitialMetadata, CallOpRecvMessage<OutputMessage>,
diff --git a/include/grpc++/impl/codegen/completion_queue.h b/include/grpc++/impl/codegen/completion_queue.h
index 03cecdc21c..61617f2bdc 100644
--- a/include/grpc++/impl/codegen/completion_queue.h
+++ b/include/grpc++/impl/codegen/completion_queue.h
@@ -102,10 +102,7 @@ class CompletionQueue : private GrpcLibraryCodegen {
  public:
   /// Default constructor. Implicitly creates a \a grpc_completion_queue
   /// instance.
-  CompletionQueue() {
-    cq_ = g_core_codegen_interface->grpc_completion_queue_create(nullptr);
-    InitialAvalanching();  // reserve this for the future shutdown
-  }
+  CompletionQueue() : CompletionQueue(false) {}
 
   /// Wrap \a take, taking ownership of the instance.
   ///
@@ -218,6 +215,18 @@ class CompletionQueue : private GrpcLibraryCodegen {
                                   const InputMessage& request,
                                   OutputMessage* result);
 
+  /// Private constructor of CompletionQueue only visible to friend classes
+  CompletionQueue(bool is_pluck) {
+    if (is_pluck) {
+      cq_ = g_core_codegen_interface->grpc_completion_queue_create_for_pluck(
+          nullptr);
+    } else {
+      cq_ = g_core_codegen_interface->grpc_completion_queue_create_for_next(
+          nullptr);
+    }
+    InitialAvalanching();  // reserve this for the future shutdown
+  }
+
   NextStatus AsyncNextInternal(void** tag, bool* ok, gpr_timespec deadline);
 
   /// Wraps \a grpc_completion_queue_pluck.
@@ -237,6 +246,12 @@ class CompletionQueue : private GrpcLibraryCodegen {
 
   /// Performs a single polling pluck on \a tag.
   /// \warning Must not be mixed with calls to \a Next.
+  ///
+  /// TODO: sreek - This calls tag->FinalizeResult() even if the cq_ is already
+  /// shutdown. This is most likely a bug and if it is a bug, then change this
+  /// implementation to simple call the other TryPluck function with a zero
+  /// timeout. i.e:
+  ///      TryPluck(tag, gpr_time_0(GPR_CLOCK_REALTIME))
   void TryPluck(CompletionQueueTag* tag) {
     auto deadline = g_core_codegen_interface->gpr_time_0(GPR_CLOCK_REALTIME);
     auto ev = g_core_codegen_interface->grpc_completion_queue_pluck(
@@ -248,6 +263,23 @@ class CompletionQueue : private GrpcLibraryCodegen {
     GPR_CODEGEN_ASSERT(!tag->FinalizeResult(&ignored, &ok));
   }
 
+  /// Performs a single polling pluck on \a tag. Calls tag->FinalizeResult if
+  /// the pluck() was successful and returned the tag.
+  ///
+  /// This exects tag->FinalizeResult (if called) to return 'false' i.e expects
+  /// that the tag is internal not something that is returned to the user.
+  void TryPluck(CompletionQueueTag* tag, gpr_timespec deadline) {
+    auto ev = g_core_codegen_interface->grpc_completion_queue_pluck(
+        cq_, tag, deadline, nullptr);
+    if (ev.type == GRPC_QUEUE_TIMEOUT || ev.type == GRPC_QUEUE_SHUTDOWN) {
+      return;
+    }
+
+    bool ok = ev.success != 0;
+    void* ignored = tag;
+    GPR_CODEGEN_ASSERT(!tag->FinalizeResult(&ignored, &ok));
+  }
+
   grpc_completion_queue* cq_;  // owned
 
   gpr_atm avalanches_in_flight_;
diff --git a/include/grpc++/impl/codegen/core_codegen.h b/include/grpc++/impl/codegen/core_codegen.h
index 90bb658455..86601076bd 100644
--- a/include/grpc++/impl/codegen/core_codegen.h
+++ b/include/grpc++/impl/codegen/core_codegen.h
@@ -38,6 +38,7 @@
 
 #include <grpc++/impl/codegen/core_codegen_interface.h>
 #include <grpc/byte_buffer.h>
+#include <grpc/grpc.h>
 #include <grpc/impl/codegen/grpc_types.h>
 
 namespace grpc {
@@ -45,7 +46,10 @@ namespace grpc {
 /// Implementation of the core codegen interface.
 class CoreCodegen : public CoreCodegenInterface {
  private:
-  grpc_completion_queue* grpc_completion_queue_create(void* reserved) override;
+  grpc_completion_queue* grpc_completion_queue_create_for_next(
+      void* reserved) override;
+  grpc_completion_queue* grpc_completion_queue_create_for_pluck(
+      void* reserved) override;
   void grpc_completion_queue_destroy(grpc_completion_queue* cq) override;
   grpc_event grpc_completion_queue_pluck(grpc_completion_queue* cq, void* tag,
                                          gpr_timespec deadline,
diff --git a/include/grpc++/impl/codegen/core_codegen_interface.h b/include/grpc++/impl/codegen/core_codegen_interface.h
index 8833de0748..a0665f4e06 100644
--- a/include/grpc++/impl/codegen/core_codegen_interface.h
+++ b/include/grpc++/impl/codegen/core_codegen_interface.h
@@ -59,7 +59,9 @@ class CoreCodegenInterface {
   virtual void assert_fail(const char* failed_assertion, const char* file,
                            int line) = 0;
 
-  virtual grpc_completion_queue* grpc_completion_queue_create(
+  virtual grpc_completion_queue* grpc_completion_queue_create_for_next(
+      void* reserved) = 0;
+  virtual grpc_completion_queue* grpc_completion_queue_create_for_pluck(
       void* reserved) = 0;
   virtual void grpc_completion_queue_destroy(grpc_completion_queue* cq) = 0;
   virtual grpc_event grpc_completion_queue_pluck(grpc_completion_queue* cq,
diff --git a/include/grpc++/impl/codegen/server_context.h b/include/grpc++/impl/codegen/server_context.h
index 91f0be06e7..ada304d571 100644
--- a/include/grpc++/impl/codegen/server_context.h
+++ b/include/grpc++/impl/codegen/server_context.h
@@ -40,6 +40,7 @@
 
 #include <grpc/impl/codegen/compression_types.h>
 
+#include <grpc++/impl/codegen/completion_queue_tag.h>
 #include <grpc++/impl/codegen/config.h>
 #include <grpc++/impl/codegen/create_auth_context.h>
 #include <grpc++/impl/codegen/metadata_map.h>
@@ -211,6 +212,8 @@ class ServerContext {
   class CompletionOp;
 
   void BeginCompletionOp(Call* call);
+  // Return the tag queued by BeginCompletionOp()
+  CompletionQueueTag* GetCompletionOpTag();
 
   ServerContext(gpr_timespec deadline, grpc_metadata_array* arr);
 
diff --git a/include/grpc++/impl/codegen/server_interface.h b/include/grpc++/impl/codegen/server_interface.h
index bd1b36e883..31d55529ef 100644
--- a/include/grpc++/impl/codegen/server_interface.h
+++ b/include/grpc++/impl/codegen/server_interface.h
@@ -122,9 +122,7 @@ class ServerInterface : public CallHook {
   /// caller is required to keep all completion queues live until the server is
   /// destroyed.
   /// \param num_cqs How many completion queues does \a cqs hold.
-  ///
-  /// \return true on a successful shutdown.
-  virtual bool Start(ServerCompletionQueue** cqs, size_t num_cqs) = 0;
+  virtual void Start(ServerCompletionQueue** cqs, size_t num_cqs) = 0;
 
   virtual void ShutdownInternal(gpr_timespec deadline) = 0;
 
diff --git a/include/grpc++/impl/codegen/status.h b/include/grpc++/impl/codegen/status.h
index 5cce3c1672..31fd6cdbe7 100644
--- a/include/grpc++/impl/codegen/status.h
+++ b/include/grpc++/impl/codegen/status.h
@@ -53,7 +53,7 @@ class Status {
 
   /// Construct an instance with \a code,  \a error_message and \a error_details
   Status(StatusCode code, const grpc::string& error_message,
-         const grpc::string error_details)
+         const grpc::string& error_details)
       : code_(code),
         error_message_(error_message),
         binary_error_details_(error_details) {}
diff --git a/include/grpc++/impl/codegen/sync_stream.h b/include/grpc++/impl/codegen/sync_stream.h
index ae3b8e441d..328d5cb1e8 100644
--- a/include/grpc++/impl/codegen/sync_stream.h
+++ b/include/grpc++/impl/codegen/sync_stream.h
@@ -155,7 +155,9 @@ class ClientReader final : public ClientReaderInterface<R> {
   template <class W>
   ClientReader(ChannelInterface* channel, const RpcMethod& method,
                ClientContext* context, const W& request)
-      : context_(context), call_(channel->CreateCall(method, context, &cq_)) {
+      : context_(context),
+        cq_(true),  // Pluckable cq
+        call_(channel->CreateCall(method, context, &cq_)) {
     CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
               CallOpClientSendClose>
         ops;
@@ -227,7 +229,9 @@ class ClientWriter : public ClientWriterInterface<W> {
   template <class R>
   ClientWriter(ChannelInterface* channel, const RpcMethod& method,
                ClientContext* context, R* response)
-      : context_(context), call_(channel->CreateCall(method, context, &cq_)) {
+      : context_(context),
+        cq_(true),  // Pluckable cq
+        call_(channel->CreateCall(method, context, &cq_)) {
     finish_ops_.RecvMessage(response);
     finish_ops_.AllowNoMessage();
 
@@ -325,7 +329,9 @@ class ClientReaderWriter final : public ClientReaderWriterInterface<W, R> {
   /// Blocking create a stream.
   ClientReaderWriter(ChannelInterface* channel, const RpcMethod& method,
                      ClientContext* context)
-      : context_(context), call_(channel->CreateCall(method, context, &cq_)) {
+      : context_(context),
+        cq_(true),  // Pluckable cq
+        call_(channel->CreateCall(method, context, &cq_)) {
     if (!context_->initial_metadata_corked_) {
       CallOpSet<CallOpSendInitialMetadata> ops;
       ops.SendInitialMetadata(context->send_initial_metadata_,
@@ -562,7 +568,7 @@ class ServerReaderWriterBody final {
   Call* const call_;
   ServerContext* const ctx_;
 };
-}
+}  // namespace internal
 
 // class to represent the user API for a bidirectional streaming call
 template <class W, class R>