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Pods/gRPC-C++/include/grpcpp/impl/call.h

@@ -0,0 +1,94 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CALL_H
+#define GRPCPP_IMPL_CALL_H
+
+#include <grpc/impl/grpc_types.h>
+#include <grpcpp/impl/call_hook.h>
+
+namespace grpc {
+class CompletionQueue;
+namespace experimental {
+class ClientRpcInfo;
+class ServerRpcInfo;
+}  // namespace experimental
+namespace internal {
+class CallHook;
+class CallOpSetInterface;
+
+/// Straightforward wrapping of the C call object
+class Call final {
+ public:
+  Call()
+      : call_hook_(nullptr),
+        cq_(nullptr),
+        call_(nullptr),
+        max_receive_message_size_(-1) {}
+  /// call is owned by the caller
+  Call(grpc_call* call, CallHook* call_hook, grpc::CompletionQueue* cq)
+      : call_hook_(call_hook),
+        cq_(cq),
+        call_(call),
+        max_receive_message_size_(-1) {}
+
+  Call(grpc_call* call, CallHook* call_hook, grpc::CompletionQueue* cq,
+       experimental::ClientRpcInfo* rpc_info)
+      : call_hook_(call_hook),
+        cq_(cq),
+        call_(call),
+        max_receive_message_size_(-1),
+        client_rpc_info_(rpc_info) {}
+
+  Call(grpc_call* call, CallHook* call_hook, grpc::CompletionQueue* cq,
+       int max_receive_message_size, experimental::ServerRpcInfo* rpc_info)
+      : call_hook_(call_hook),
+        cq_(cq),
+        call_(call),
+        max_receive_message_size_(max_receive_message_size),
+        server_rpc_info_(rpc_info) {}
+
+  void PerformOps(CallOpSetInterface* ops) {
+    call_hook_->PerformOpsOnCall(ops, this);
+  }
+
+  grpc_call* call() const { return call_; }
+  grpc::CompletionQueue* cq() const { return cq_; }
+
+  int max_receive_message_size() const { return max_receive_message_size_; }
+
+  experimental::ClientRpcInfo* client_rpc_info() const {
+    return client_rpc_info_;
+  }
+
+  experimental::ServerRpcInfo* server_rpc_info() const {
+    return server_rpc_info_;
+  }
+
+ private:
+  CallHook* call_hook_;
+  grpc::CompletionQueue* cq_;
+  grpc_call* call_;
+  int max_receive_message_size_;
+  experimental::ClientRpcInfo* client_rpc_info_ = nullptr;
+  experimental::ServerRpcInfo* server_rpc_info_ = nullptr;
+};
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CALL_H

Pods/gRPC-C++/include/grpcpp/impl/call_hook.h

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+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CALL_HOOK_H
+#define GRPCPP_IMPL_CALL_HOOK_H
+
+namespace grpc {
+
+namespace internal {
+class CallOpSetInterface;
+class Call;
+
+/// This is an interface that Channel and Server implement to allow them to hook
+/// performing ops.
+class CallHook {
+ public:
+  virtual ~CallHook() {}
+  virtual void PerformOpsOnCall(CallOpSetInterface* ops, Call* call) = 0;
+};
+}  // namespace internal
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CALL_HOOK_H

Pods/gRPC-C++/include/grpcpp/impl/call_op_set.h

@@ -0,0 +1,1036 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CALL_OP_SET_H
+#define GRPCPP_IMPL_CALL_OP_SET_H
+
+#include <cstring>
+#include <map>
+#include <memory>
+
+#include <grpc/grpc.h>
+#include <grpc/impl/compression_types.h>
+#include <grpc/impl/grpc_types.h>
+#include <grpc/slice.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpcpp/client_context.h>
+#include <grpcpp/completion_queue.h>
+#include <grpcpp/impl/call.h>
+#include <grpcpp/impl/call_hook.h>
+#include <grpcpp/impl/call_op_set_interface.h>
+#include <grpcpp/impl/codegen/intercepted_channel.h>
+#include <grpcpp/impl/completion_queue_tag.h>
+#include <grpcpp/impl/interceptor_common.h>
+#include <grpcpp/impl/serialization_traits.h>
+#include <grpcpp/support/byte_buffer.h>
+#include <grpcpp/support/config.h>
+#include <grpcpp/support/slice.h>
+#include <grpcpp/support/string_ref.h>
+
+namespace grpc {
+
+namespace internal {
+class Call;
+class CallHook;
+
+// TODO(yangg) if the map is changed before we send, the pointers will be a
+// mess. Make sure it does not happen.
+inline grpc_metadata* FillMetadataArray(
+    const std::multimap<std::string, std::string>& metadata,
+    size_t* metadata_count, const std::string& optional_error_details) {
+  *metadata_count = metadata.size() + (optional_error_details.empty() ? 0 : 1);
+  if (*metadata_count == 0) {
+    return nullptr;
+  }
+  grpc_metadata* metadata_array = static_cast<grpc_metadata*>(
+      gpr_malloc((*metadata_count) * sizeof(grpc_metadata)));
+  size_t i = 0;
+  for (auto iter = metadata.cbegin(); iter != metadata.cend(); ++iter, ++i) {
+    metadata_array[i].key = SliceReferencingString(iter->first);
+    metadata_array[i].value = SliceReferencingString(iter->second);
+  }
+  if (!optional_error_details.empty()) {
+    metadata_array[i].key = grpc_slice_from_static_buffer(
+        kBinaryErrorDetailsKey, sizeof(kBinaryErrorDetailsKey) - 1);
+    metadata_array[i].value = SliceReferencingString(optional_error_details);
+  }
+  return metadata_array;
+}
+}  // namespace internal
+
+/// Per-message write options.
+class WriteOptions {
+ public:
+  WriteOptions() : flags_(0), last_message_(false) {}
+
+  /// Clear all flags.
+  inline void Clear() { flags_ = 0; }
+
+  /// Returns raw flags bitset.
+  inline uint32_t flags() const { return flags_; }
+
+  /// Sets flag for the disabling of compression for the next message write.
+  ///
+  /// \sa GRPC_WRITE_NO_COMPRESS
+  inline WriteOptions& set_no_compression() {
+    SetBit(GRPC_WRITE_NO_COMPRESS);
+    return *this;
+  }
+
+  /// Clears flag for the disabling of compression for the next message write.
+  ///
+  /// \sa GRPC_WRITE_NO_COMPRESS
+  inline WriteOptions& clear_no_compression() {
+    ClearBit(GRPC_WRITE_NO_COMPRESS);
+    return *this;
+  }
+
+  /// Get value for the flag indicating whether compression for the next
+  /// message write is forcefully disabled.
+  ///
+  /// \sa GRPC_WRITE_NO_COMPRESS
+  inline bool get_no_compression() const {
+    return GetBit(GRPC_WRITE_NO_COMPRESS);
+  }
+
+  /// Sets flag indicating that the write may be buffered and need not go out on
+  /// the wire immediately.
+  ///
+  /// \sa GRPC_WRITE_BUFFER_HINT
+  inline WriteOptions& set_buffer_hint() {
+    SetBit(GRPC_WRITE_BUFFER_HINT);
+    return *this;
+  }
+
+  /// Clears flag indicating that the write may be buffered and need not go out
+  /// on the wire immediately.
+  ///
+  /// \sa GRPC_WRITE_BUFFER_HINT
+  inline WriteOptions& clear_buffer_hint() {
+    ClearBit(GRPC_WRITE_BUFFER_HINT);
+    return *this;
+  }
+
+  /// Get value for the flag indicating that the write may be buffered and need
+  /// not go out on the wire immediately.
+  ///
+  /// \sa GRPC_WRITE_BUFFER_HINT
+  inline bool get_buffer_hint() const { return GetBit(GRPC_WRITE_BUFFER_HINT); }
+
+  /// corked bit: aliases set_buffer_hint currently, with the intent that
+  /// set_buffer_hint will be removed in the future
+  inline WriteOptions& set_corked() {
+    SetBit(GRPC_WRITE_BUFFER_HINT);
+    return *this;
+  }
+
+  inline WriteOptions& clear_corked() {
+    ClearBit(GRPC_WRITE_BUFFER_HINT);
+    return *this;
+  }
+
+  inline bool is_corked() const { return GetBit(GRPC_WRITE_BUFFER_HINT); }
+
+  /// last-message bit: indicates this is the last message in a stream
+  /// client-side:  makes Write the equivalent of performing Write, WritesDone
+  /// in a single step
+  /// server-side:  hold the Write until the service handler returns (sync api)
+  /// or until Finish is called (async api)
+  inline WriteOptions& set_last_message() {
+    last_message_ = true;
+    return *this;
+  }
+
+  /// Clears flag indicating that this is the last message in a stream,
+  /// disabling coalescing.
+  inline WriteOptions& clear_last_message() {
+    last_message_ = false;
+    return *this;
+  }
+
+  /// Get value for the flag indicating that this is the last message, and
+  /// should be coalesced with trailing metadata.
+  ///
+  /// \sa GRPC_WRITE_LAST_MESSAGE
+  bool is_last_message() const { return last_message_; }
+
+  /// Guarantee that all bytes have been written to the socket before completing
+  /// this write (usually writes are completed when they pass flow control).
+  inline WriteOptions& set_write_through() {
+    SetBit(GRPC_WRITE_THROUGH);
+    return *this;
+  }
+
+  inline WriteOptions& clear_write_through() {
+    ClearBit(GRPC_WRITE_THROUGH);
+    return *this;
+  }
+
+  inline bool is_write_through() const { return GetBit(GRPC_WRITE_THROUGH); }
+
+ private:
+  void SetBit(const uint32_t mask) { flags_ |= mask; }
+
+  void ClearBit(const uint32_t mask) { flags_ &= ~mask; }
+
+  bool GetBit(const uint32_t mask) const { return (flags_ & mask) != 0; }
+
+  uint32_t flags_;
+  bool last_message_;
+};
+
+namespace internal {
+
+/// Default argument for CallOpSet. The Unused parameter is unused by
+/// the class, but can be used for generating multiple names for the
+/// same thing.
+template <int Unused>
+class CallNoOp {
+ protected:
+  void AddOp(grpc_op* /*ops*/, size_t* /*nops*/) {}
+  void FinishOp(bool* /*status*/) {}
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* /*interceptor_methods*/) {}
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* /*interceptor_methods*/) {}
+  void SetHijackingState(InterceptorBatchMethodsImpl* /*interceptor_methods*/) {
+  }
+};
+
+class CallOpSendInitialMetadata {
+ public:
+  CallOpSendInitialMetadata() : send_(false) {
+    maybe_compression_level_.is_set = false;
+  }
+
+  void SendInitialMetadata(std::multimap<std::string, std::string>* metadata,
+                           uint32_t flags) {
+    maybe_compression_level_.is_set = false;
+    send_ = true;
+    flags_ = flags;
+    metadata_map_ = metadata;
+  }
+
+  void set_compression_level(grpc_compression_level level) {
+    maybe_compression_level_.is_set = true;
+    maybe_compression_level_.level = level;
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!send_ || hijacked_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_INITIAL_METADATA;
+    op->flags = flags_;
+    op->reserved = nullptr;
+    initial_metadata_ =
+        FillMetadataArray(*metadata_map_, &initial_metadata_count_, "");
+    op->data.send_initial_metadata.count = initial_metadata_count_;
+    op->data.send_initial_metadata.metadata = initial_metadata_;
+    op->data.send_initial_metadata.maybe_compression_level.is_set =
+        maybe_compression_level_.is_set;
+    if (maybe_compression_level_.is_set) {
+      op->data.send_initial_metadata.maybe_compression_level.level =
+          maybe_compression_level_.level;
+    }
+  }
+  void FinishOp(bool* /*status*/) {
+    if (!send_ || hijacked_) return;
+    gpr_free(initial_metadata_);
+    send_ = false;
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (!send_) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_SEND_INITIAL_METADATA);
+    interceptor_methods->SetSendInitialMetadata(metadata_map_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* /*interceptor_methods*/) {}
+
+  void SetHijackingState(InterceptorBatchMethodsImpl* /*interceptor_methods*/) {
+    hijacked_ = true;
+  }
+
+  bool hijacked_ = false;
+  bool send_;
+  uint32_t flags_;
+  size_t initial_metadata_count_;
+  std::multimap<std::string, std::string>* metadata_map_;
+  grpc_metadata* initial_metadata_;
+  struct {
+    bool is_set;
+    grpc_compression_level level;
+  } maybe_compression_level_;
+};
+
+class CallOpSendMessage {
+ public:
+  CallOpSendMessage() : send_buf_() {}
+
+  /// Send \a message using \a options for the write. The \a options are cleared
+  /// after use.
+  template <class M>
+  GRPC_MUST_USE_RESULT Status SendMessage(const M& message,
+                                          WriteOptions options);
+
+  template <class M>
+  GRPC_MUST_USE_RESULT Status SendMessage(const M& message);
+
+  /// Send \a message using \a options for the write. The \a options are cleared
+  /// after use. This form of SendMessage allows gRPC to reference \a message
+  /// beyond the lifetime of SendMessage.
+  template <class M>
+  GRPC_MUST_USE_RESULT Status SendMessagePtr(const M* message,
+                                             WriteOptions options);
+
+  /// This form of SendMessage allows gRPC to reference \a message beyond the
+  /// lifetime of SendMessage.
+  template <class M>
+  GRPC_MUST_USE_RESULT Status SendMessagePtr(const M* message);
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (msg_ == nullptr && !send_buf_.Valid()) return;
+    if (hijacked_) {
+      serializer_ = nullptr;
+      return;
+    }
+    if (msg_ != nullptr) {
+      GPR_ASSERT(serializer_(msg_).ok());
+    }
+    serializer_ = nullptr;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_MESSAGE;
+    op->flags = write_options_.flags();
+    op->reserved = nullptr;
+    op->data.send_message.send_message = send_buf_.c_buffer();
+    // Flags are per-message: clear them after use.
+    write_options_.Clear();
+  }
+  void FinishOp(bool* status) {
+    if (msg_ == nullptr && !send_buf_.Valid()) return;
+    send_buf_.Clear();
+    if (hijacked_ && failed_send_) {
+      // Hijacking interceptor failed this Op
+      *status = false;
+    } else if (!*status) {
+      // This Op was passed down to core and the Op failed
+      failed_send_ = true;
+    }
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (msg_ == nullptr && !send_buf_.Valid()) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_SEND_MESSAGE);
+    interceptor_methods->SetSendMessage(&send_buf_, &msg_, &failed_send_,
+                                        serializer_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (msg_ != nullptr || send_buf_.Valid()) {
+      interceptor_methods->AddInterceptionHookPoint(
+          experimental::InterceptionHookPoints::POST_SEND_MESSAGE);
+    }
+    send_buf_.Clear();
+    msg_ = nullptr;
+    // The contents of the SendMessage value that was previously set
+    // has had its references stolen by core's operations
+    interceptor_methods->SetSendMessage(nullptr, nullptr, &failed_send_,
+                                        nullptr);
+  }
+
+  void SetHijackingState(InterceptorBatchMethodsImpl* /*interceptor_methods*/) {
+    hijacked_ = true;
+  }
+
+ private:
+  const void* msg_ = nullptr;  // The original non-serialized message
+  bool hijacked_ = false;
+  bool failed_send_ = false;
+  ByteBuffer send_buf_;
+  WriteOptions write_options_;
+  std::function<Status(const void*)> serializer_;
+};
+
+template <class M>
+Status CallOpSendMessage::SendMessage(const M& message, WriteOptions options) {
+  write_options_ = options;
+  // Serialize immediately since we do not have access to the message pointer
+  bool own_buf;
+  Status result = SerializationTraits<M>::Serialize(
+      message, send_buf_.bbuf_ptr(), &own_buf);
+  if (!own_buf) {
+    send_buf_.Duplicate();
+  }
+  return result;
+}
+
+template <class M>
+Status CallOpSendMessage::SendMessage(const M& message) {
+  return SendMessage(message, WriteOptions());
+}
+
+template <class M>
+Status CallOpSendMessage::SendMessagePtr(const M* message,
+                                         WriteOptions options) {
+  msg_ = message;
+  write_options_ = options;
+  // Store the serializer for later since we have access to the message
+  serializer_ = [this](const void* message) {
+    bool own_buf;
+    // TODO(vjpai): Remove the void below when possible
+    // The void in the template parameter below should not be needed
+    // (since it should be implicit) but is needed due to an observed
+    // difference in behavior between clang and gcc for certain internal users
+    Status result = SerializationTraits<M>::Serialize(
+        *static_cast<const M*>(message), send_buf_.bbuf_ptr(), &own_buf);
+    if (!own_buf) {
+      send_buf_.Duplicate();
+    }
+    return result;
+  };
+  return Status();
+}
+
+template <class M>
+Status CallOpSendMessage::SendMessagePtr(const M* message) {
+  return SendMessagePtr(message, WriteOptions());
+}
+
+template <class R>
+class CallOpRecvMessage {
+ public:
+  void RecvMessage(R* message) { message_ = message; }
+
+  // Do not change status if no message is received.
+  void AllowNoMessage() { allow_not_getting_message_ = true; }
+
+  bool got_message = false;
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (message_ == nullptr || hijacked_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_MESSAGE;
+    op->flags = 0;
+    op->reserved = nullptr;
+    op->data.recv_message.recv_message = recv_buf_.c_buffer_ptr();
+  }
+
+  void FinishOp(bool* status) {
+    if (message_ == nullptr) return;
+    if (recv_buf_.Valid()) {
+      if (*status) {
+        got_message = *status =
+            SerializationTraits<R>::Deserialize(recv_buf_.bbuf_ptr(), message_)
+                .ok();
+        recv_buf_.Release();
+      } else {
+        got_message = false;
+        recv_buf_.Clear();
+      }
+    } else if (hijacked_) {
+      if (hijacked_recv_message_failed_) {
+        FinishOpRecvMessageFailureHandler(status);
+      } else {
+        // The op was hijacked and it was successful. There is no further action
+        // to be performed since the message is already in its non-serialized
+        // form.
+      }
+    } else {
+      FinishOpRecvMessageFailureHandler(status);
+    }
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (message_ == nullptr) return;
+    interceptor_methods->SetRecvMessage(message_,
+                                        &hijacked_recv_message_failed_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (message_ == nullptr) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::POST_RECV_MESSAGE);
+    if (!got_message) interceptor_methods->SetRecvMessage(nullptr, nullptr);
+  }
+  void SetHijackingState(InterceptorBatchMethodsImpl* interceptor_methods) {
+    hijacked_ = true;
+    if (message_ == nullptr) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_RECV_MESSAGE);
+    got_message = true;
+  }
+
+ private:
+  // Sets got_message and \a status for a failed recv message op
+  void FinishOpRecvMessageFailureHandler(bool* status) {
+    got_message = false;
+    if (!allow_not_getting_message_) {
+      *status = false;
+    }
+  }
+
+  R* message_ = nullptr;
+  ByteBuffer recv_buf_;
+  bool allow_not_getting_message_ = false;
+  bool hijacked_ = false;
+  bool hijacked_recv_message_failed_ = false;
+};
+
+class DeserializeFunc {
+ public:
+  virtual Status Deserialize(ByteBuffer* buf) = 0;
+  virtual ~DeserializeFunc() {}
+};
+
+template <class R>
+class DeserializeFuncType final : public DeserializeFunc {
+ public:
+  explicit DeserializeFuncType(R* message) : message_(message) {}
+  Status Deserialize(ByteBuffer* buf) override {
+    return SerializationTraits<R>::Deserialize(buf->bbuf_ptr(), message_);
+  }
+
+  ~DeserializeFuncType() override {}
+
+ private:
+  R* message_;  // Not a managed pointer because management is external to this
+};
+
+class CallOpGenericRecvMessage {
+ public:
+  template <class R>
+  void RecvMessage(R* message) {
+    // Use an explicit base class pointer to avoid resolution error in the
+    // following unique_ptr::reset for some old implementations.
+    DeserializeFunc* func = new DeserializeFuncType<R>(message);
+    deserialize_.reset(func);
+    message_ = message;
+  }
+
+  // Do not change status if no message is received.
+  void AllowNoMessage() { allow_not_getting_message_ = true; }
+
+  bool got_message = false;
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!deserialize_ || hijacked_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_MESSAGE;
+    op->flags = 0;
+    op->reserved = nullptr;
+    op->data.recv_message.recv_message = recv_buf_.c_buffer_ptr();
+  }
+
+  void FinishOp(bool* status) {
+    if (!deserialize_) return;
+    if (recv_buf_.Valid()) {
+      if (*status) {
+        got_message = true;
+        *status = deserialize_->Deserialize(&recv_buf_).ok();
+        recv_buf_.Release();
+      } else {
+        got_message = false;
+        recv_buf_.Clear();
+      }
+    } else if (hijacked_) {
+      if (hijacked_recv_message_failed_) {
+        FinishOpRecvMessageFailureHandler(status);
+      } else {
+        // The op was hijacked and it was successful. There is no further action
+        // to be performed since the message is already in its non-serialized
+        // form.
+      }
+    } else {
+      got_message = false;
+      if (!allow_not_getting_message_) {
+        *status = false;
+      }
+    }
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (!deserialize_) return;
+    interceptor_methods->SetRecvMessage(message_,
+                                        &hijacked_recv_message_failed_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (!deserialize_) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::POST_RECV_MESSAGE);
+    if (!got_message) interceptor_methods->SetRecvMessage(nullptr, nullptr);
+    deserialize_.reset();
+  }
+  void SetHijackingState(InterceptorBatchMethodsImpl* interceptor_methods) {
+    hijacked_ = true;
+    if (!deserialize_) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_RECV_MESSAGE);
+    got_message = true;
+  }
+
+ private:
+  // Sets got_message and \a status for a failed recv message op
+  void FinishOpRecvMessageFailureHandler(bool* status) {
+    got_message = false;
+    if (!allow_not_getting_message_) {
+      *status = false;
+    }
+  }
+
+  void* message_ = nullptr;
+  std::unique_ptr<DeserializeFunc> deserialize_;
+  ByteBuffer recv_buf_;
+  bool allow_not_getting_message_ = false;
+  bool hijacked_ = false;
+  bool hijacked_recv_message_failed_ = false;
+};
+
+class CallOpClientSendClose {
+ public:
+  CallOpClientSendClose() : send_(false) {}
+
+  void ClientSendClose() { send_ = true; }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!send_ || hijacked_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
+    op->flags = 0;
+    op->reserved = nullptr;
+  }
+  void FinishOp(bool* /*status*/) { send_ = false; }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (!send_) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_SEND_CLOSE);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* /*interceptor_methods*/) {}
+
+  void SetHijackingState(InterceptorBatchMethodsImpl* /*interceptor_methods*/) {
+    hijacked_ = true;
+  }
+
+ private:
+  bool hijacked_ = false;
+  bool send_;
+};
+
+class CallOpServerSendStatus {
+ public:
+  CallOpServerSendStatus() : send_status_available_(false) {}
+
+  void ServerSendStatus(
+      std::multimap<std::string, std::string>* trailing_metadata,
+      const Status& status) {
+    send_error_details_ = status.error_details();
+    metadata_map_ = trailing_metadata;
+    send_status_available_ = true;
+    send_status_code_ = static_cast<grpc_status_code>(status.error_code());
+    send_error_message_ = status.error_message();
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (!send_status_available_ || hijacked_) return;
+    trailing_metadata_ = FillMetadataArray(
+        *metadata_map_, &trailing_metadata_count_, send_error_details_);
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
+    op->data.send_status_from_server.trailing_metadata_count =
+        trailing_metadata_count_;
+    op->data.send_status_from_server.trailing_metadata = trailing_metadata_;
+    op->data.send_status_from_server.status = send_status_code_;
+    error_message_slice_ = SliceReferencingString(send_error_message_);
+    op->data.send_status_from_server.status_details =
+        send_error_message_.empty() ? nullptr : &error_message_slice_;
+    op->flags = 0;
+    op->reserved = nullptr;
+  }
+
+  void FinishOp(bool* /*status*/) {
+    if (!send_status_available_ || hijacked_) return;
+    gpr_free(trailing_metadata_);
+    send_status_available_ = false;
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (!send_status_available_) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_SEND_STATUS);
+    interceptor_methods->SetSendTrailingMetadata(metadata_map_);
+    interceptor_methods->SetSendStatus(&send_status_code_, &send_error_details_,
+                                       &send_error_message_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* /*interceptor_methods*/) {}
+
+  void SetHijackingState(InterceptorBatchMethodsImpl* /*interceptor_methods*/) {
+    hijacked_ = true;
+  }
+
+ private:
+  bool hijacked_ = false;
+  bool send_status_available_;
+  grpc_status_code send_status_code_;
+  std::string send_error_details_;
+  std::string send_error_message_;
+  size_t trailing_metadata_count_;
+  std::multimap<std::string, std::string>* metadata_map_;
+  grpc_metadata* trailing_metadata_;
+  grpc_slice error_message_slice_;
+};
+
+class CallOpRecvInitialMetadata {
+ public:
+  CallOpRecvInitialMetadata() : metadata_map_(nullptr) {}
+
+  void RecvInitialMetadata(grpc::ClientContext* context) {
+    context->initial_metadata_received_ = true;
+    metadata_map_ = &context->recv_initial_metadata_;
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (metadata_map_ == nullptr || hijacked_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_INITIAL_METADATA;
+    op->data.recv_initial_metadata.recv_initial_metadata = metadata_map_->arr();
+    op->flags = 0;
+    op->reserved = nullptr;
+  }
+
+  void FinishOp(bool* /*status*/) {
+    if (metadata_map_ == nullptr || hijacked_) return;
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    interceptor_methods->SetRecvInitialMetadata(metadata_map_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (metadata_map_ == nullptr) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::POST_RECV_INITIAL_METADATA);
+    metadata_map_ = nullptr;
+  }
+
+  void SetHijackingState(InterceptorBatchMethodsImpl* interceptor_methods) {
+    hijacked_ = true;
+    if (metadata_map_ == nullptr) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_RECV_INITIAL_METADATA);
+  }
+
+ private:
+  bool hijacked_ = false;
+  MetadataMap* metadata_map_;
+};
+
+class CallOpClientRecvStatus {
+ public:
+  CallOpClientRecvStatus()
+      : recv_status_(nullptr), debug_error_string_(nullptr) {}
+
+  void ClientRecvStatus(grpc::ClientContext* context, Status* status) {
+    client_context_ = context;
+    metadata_map_ = &client_context_->trailing_metadata_;
+    recv_status_ = status;
+    error_message_ = grpc_empty_slice();
+  }
+
+ protected:
+  void AddOp(grpc_op* ops, size_t* nops) {
+    if (recv_status_ == nullptr || hijacked_) return;
+    grpc_op* op = &ops[(*nops)++];
+    op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
+    op->data.recv_status_on_client.trailing_metadata = metadata_map_->arr();
+    op->data.recv_status_on_client.status = &status_code_;
+    op->data.recv_status_on_client.status_details = &error_message_;
+    op->data.recv_status_on_client.error_string = &debug_error_string_;
+    op->flags = 0;
+    op->reserved = nullptr;
+  }
+
+  void FinishOp(bool* /*status*/) {
+    if (recv_status_ == nullptr || hijacked_) return;
+    if (static_cast<StatusCode>(status_code_) == StatusCode::OK) {
+      *recv_status_ = Status();
+      GPR_DEBUG_ASSERT(debug_error_string_ == nullptr);
+    } else {
+      *recv_status_ =
+          Status(static_cast<StatusCode>(status_code_),
+                 GRPC_SLICE_IS_EMPTY(error_message_)
+                     ? std::string()
+                     : std::string(GRPC_SLICE_START_PTR(error_message_),
+                                   GRPC_SLICE_END_PTR(error_message_)),
+                 metadata_map_->GetBinaryErrorDetails());
+      if (debug_error_string_ != nullptr) {
+        client_context_->set_debug_error_string(debug_error_string_);
+        gpr_free(const_cast<char*>(debug_error_string_));
+      }
+    }
+    // TODO(soheil): Find callers that set debug string even for status OK,
+    //               and fix them.
+    grpc_slice_unref(error_message_);
+  }
+
+  void SetInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    interceptor_methods->SetRecvStatus(recv_status_);
+    interceptor_methods->SetRecvTrailingMetadata(metadata_map_);
+  }
+
+  void SetFinishInterceptionHookPoint(
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (recv_status_ == nullptr) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::POST_RECV_STATUS);
+    recv_status_ = nullptr;
+  }
+
+  void SetHijackingState(InterceptorBatchMethodsImpl* interceptor_methods) {
+    hijacked_ = true;
+    if (recv_status_ == nullptr) return;
+    interceptor_methods->AddInterceptionHookPoint(
+        experimental::InterceptionHookPoints::PRE_RECV_STATUS);
+  }
+
+ private:
+  bool hijacked_ = false;
+  grpc::ClientContext* client_context_;
+  MetadataMap* metadata_map_;
+  Status* recv_status_;
+  const char* debug_error_string_;
+  grpc_status_code status_code_;
+  grpc_slice error_message_;
+};
+
+template <class Op1 = CallNoOp<1>, class Op2 = CallNoOp<2>,
+          class Op3 = CallNoOp<3>, class Op4 = CallNoOp<4>,
+          class Op5 = CallNoOp<5>, class Op6 = CallNoOp<6>>
+class CallOpSet;
+
+/// Primary implementation of CallOpSetInterface.
+/// Since we cannot use variadic templates, we declare slots up to
+/// the maximum count of ops we'll need in a set. We leverage the
+/// empty base class optimization to slim this class (especially
+/// when there are many unused slots used). To avoid duplicate base classes,
+/// the template parameter for CallNoOp is varied by argument position.
+template <class Op1, class Op2, class Op3, class Op4, class Op5, class Op6>
+class CallOpSet : public CallOpSetInterface,
+                  public Op1,
+                  public Op2,
+                  public Op3,
+                  public Op4,
+                  public Op5,
+                  public Op6 {
+ public:
+  CallOpSet() : core_cq_tag_(this), return_tag_(this) {}
+  // The copy constructor and assignment operator reset the value of
+  // core_cq_tag_, return_tag_, done_intercepting_ and interceptor_methods_
+  // since those are only meaningful on a specific object, not across objects.
+  CallOpSet(const CallOpSet& other)
+      : core_cq_tag_(this),
+        return_tag_(this),
+        call_(other.call_),
+        done_intercepting_(false),
+        interceptor_methods_(InterceptorBatchMethodsImpl()) {}
+
+  CallOpSet& operator=(const CallOpSet& other) {
+    if (&other == this) {
+      return *this;
+    }
+    core_cq_tag_ = this;
+    return_tag_ = this;
+    call_ = other.call_;
+    done_intercepting_ = false;
+    interceptor_methods_ = InterceptorBatchMethodsImpl();
+    return *this;
+  }
+
+  void FillOps(Call* call) override {
+    done_intercepting_ = false;
+    grpc_call_ref(call->call());
+    call_ =
+        *call;  // It's fine to create a copy of call since it's just pointers
+
+    if (RunInterceptors()) {
+      ContinueFillOpsAfterInterception();
+    } else {
+      // After the interceptors are run, ContinueFillOpsAfterInterception will
+      // be run
+    }
+  }
+
+  bool FinalizeResult(void** tag, bool* status) override {
+    if (done_intercepting_) {
+      // Complete the avalanching since we are done with this batch of ops
+      call_.cq()->CompleteAvalanching();
+      // We have already finished intercepting and filling in the results. This
+      // round trip from the core needed to be made because interceptors were
+      // run
+      *tag = return_tag_;
+      *status = saved_status_;
+      grpc_call_unref(call_.call());
+      return true;
+    }
+
+    this->Op1::FinishOp(status);
+    this->Op2::FinishOp(status);
+    this->Op3::FinishOp(status);
+    this->Op4::FinishOp(status);
+    this->Op5::FinishOp(status);
+    this->Op6::FinishOp(status);
+    saved_status_ = *status;
+    if (RunInterceptorsPostRecv()) {
+      *tag = return_tag_;
+      grpc_call_unref(call_.call());
+      return true;
+    }
+    // Interceptors are going to be run, so we can't return the tag just yet.
+    // After the interceptors are run, ContinueFinalizeResultAfterInterception
+    return false;
+  }
+
+  void set_output_tag(void* return_tag) { return_tag_ = return_tag; }
+
+  void* core_cq_tag() override { return core_cq_tag_; }
+
+  /// set_core_cq_tag is used to provide a different core CQ tag than "this".
+  /// This is used for callback-based tags, where the core tag is the core
+  /// callback function. It does not change the use or behavior of any other
+  /// function (such as FinalizeResult)
+  void set_core_cq_tag(void* core_cq_tag) { core_cq_tag_ = core_cq_tag; }
+
+  // This will be called while interceptors are run if the RPC is a hijacked
+  // RPC. This should set hijacking state for each of the ops.
+  void SetHijackingState() override {
+    this->Op1::SetHijackingState(&interceptor_methods_);
+    this->Op2::SetHijackingState(&interceptor_methods_);
+    this->Op3::SetHijackingState(&interceptor_methods_);
+    this->Op4::SetHijackingState(&interceptor_methods_);
+    this->Op5::SetHijackingState(&interceptor_methods_);
+    this->Op6::SetHijackingState(&interceptor_methods_);
+  }
+
+  // Should be called after interceptors are done running
+  void ContinueFillOpsAfterInterception() override {
+    static const size_t MAX_OPS = 6;
+    grpc_op ops[MAX_OPS];
+    size_t nops = 0;
+    this->Op1::AddOp(ops, &nops);
+    this->Op2::AddOp(ops, &nops);
+    this->Op3::AddOp(ops, &nops);
+    this->Op4::AddOp(ops, &nops);
+    this->Op5::AddOp(ops, &nops);
+    this->Op6::AddOp(ops, &nops);
+
+    grpc_call_error err =
+        grpc_call_start_batch(call_.call(), ops, nops, core_cq_tag(), nullptr);
+
+    if (err != GRPC_CALL_OK) {
+      // A failure here indicates an API misuse; for example, doing a Write
+      // while another Write is already pending on the same RPC or invoking
+      // WritesDone multiple times
+      gpr_log(GPR_ERROR, "API misuse of type %s observed",
+              grpc_call_error_to_string(err));
+      GPR_ASSERT(false);
+    }
+  }
+
+  // Should be called after interceptors are done running on the finalize result
+  // path
+  void ContinueFinalizeResultAfterInterception() override {
+    done_intercepting_ = true;
+    // The following call_start_batch is internally-generated so no need for an
+    // explanatory log on failure.
+    GPR_ASSERT(grpc_call_start_batch(call_.call(), nullptr, 0, core_cq_tag(),
+                                     nullptr) == GRPC_CALL_OK);
+  }
+
+ private:
+  // Returns true if no interceptors need to be run
+  bool RunInterceptors() {
+    interceptor_methods_.ClearState();
+    interceptor_methods_.SetCallOpSetInterface(this);
+    interceptor_methods_.SetCall(&call_);
+    this->Op1::SetInterceptionHookPoint(&interceptor_methods_);
+    this->Op2::SetInterceptionHookPoint(&interceptor_methods_);
+    this->Op3::SetInterceptionHookPoint(&interceptor_methods_);
+    this->Op4::SetInterceptionHookPoint(&interceptor_methods_);
+    this->Op5::SetInterceptionHookPoint(&interceptor_methods_);
+    this->Op6::SetInterceptionHookPoint(&interceptor_methods_);
+    if (interceptor_methods_.InterceptorsListEmpty()) {
+      return true;
+    }
+    // This call will go through interceptors and would need to
+    // schedule new batches, so delay completion queue shutdown
+    call_.cq()->RegisterAvalanching();
+    return interceptor_methods_.RunInterceptors();
+  }
+  // Returns true if no interceptors need to be run
+  bool RunInterceptorsPostRecv() {
+    // Call and OpSet had already been set on the set state.
+    // SetReverse also clears previously set hook points
+    interceptor_methods_.SetReverse();
+    this->Op1::SetFinishInterceptionHookPoint(&interceptor_methods_);
+    this->Op2::SetFinishInterceptionHookPoint(&interceptor_methods_);
+    this->Op3::SetFinishInterceptionHookPoint(&interceptor_methods_);
+    this->Op4::SetFinishInterceptionHookPoint(&interceptor_methods_);
+    this->Op5::SetFinishInterceptionHookPoint(&interceptor_methods_);
+    this->Op6::SetFinishInterceptionHookPoint(&interceptor_methods_);
+    return interceptor_methods_.RunInterceptors();
+  }
+
+  void* core_cq_tag_;
+  void* return_tag_;
+  Call call_;
+  bool done_intercepting_ = false;
+  InterceptorBatchMethodsImpl interceptor_methods_;
+  bool saved_status_;
+};
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CALL_OP_SET_H

Pods/gRPC-C++/include/grpcpp/impl/call_op_set_interface.h

@@ -0,0 +1,61 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CALL_OP_SET_INTERFACE_H
+#define GRPCPP_IMPL_CALL_OP_SET_INTERFACE_H
+
+// IWYU pragma: private
+
+#include <grpcpp/impl/completion_queue_tag.h>
+
+namespace grpc {
+namespace internal {
+
+class Call;
+
+/// An abstract collection of call ops, used to generate the
+/// grpc_call_op structure to pass down to the lower layers,
+/// and as it is-a CompletionQueueTag, also massages the final
+/// completion into the correct form for consumption in the C++
+/// API.
+class CallOpSetInterface : public CompletionQueueTag {
+ public:
+  /// Fills in grpc_op, starting from ops[*nops] and moving
+  /// upwards.
+  virtual void FillOps(internal::Call* call) = 0;
+
+  /// Get the tag to be used at the core completion queue. Generally, the
+  /// value of core_cq_tag will be "this". However, it can be overridden if we
+  /// want core to process the tag differently (e.g., as a core callback)
+  virtual void* core_cq_tag() = 0;
+
+  // This will be called while interceptors are run if the RPC is a hijacked
+  // RPC. This should set hijacking state for each of the ops.
+  virtual void SetHijackingState() = 0;
+
+  // Should be called after interceptors are done running
+  virtual void ContinueFillOpsAfterInterception() = 0;
+
+  // Should be called after interceptors are done running on the finalize result
+  // path
+  virtual void ContinueFinalizeResultAfterInterception() = 0;
+};
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CALL_OP_SET_INTERFACE_H

Pods/gRPC-C++/include/grpcpp/impl/channel_argument_option.h

@@ -0,0 +1,39 @@
+//
+//
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CHANNEL_ARGUMENT_OPTION_H
+#define GRPCPP_IMPL_CHANNEL_ARGUMENT_OPTION_H
+
+#include <map>
+#include <memory>
+
+#include <grpcpp/impl/server_builder_option.h>
+#include <grpcpp/support/channel_arguments.h>
+
+namespace grpc {
+
+std::unique_ptr<ServerBuilderOption> MakeChannelArgumentOption(
+    const std::string& name, const std::string& value);
+std::unique_ptr<ServerBuilderOption> MakeChannelArgumentOption(
+    const std::string& name, int value);
+std::unique_ptr<ServerBuilderOption> MakeChannelArgumentOption(
+    const std::string& name, void* value);
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CHANNEL_ARGUMENT_OPTION_H

Pods/gRPC-C++/include/grpcpp/impl/channel_interface.h

@@ -0,0 +1,170 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CHANNEL_INTERFACE_H
+#define GRPCPP_IMPL_CHANNEL_INTERFACE_H
+
+#include <grpc/impl/connectivity_state.h>
+#include <grpcpp/impl/call.h>
+#include <grpcpp/support/status.h>
+#include <grpcpp/support/time.h>
+
+namespace grpc {
+template <class R>
+class ClientReader;
+template <class W>
+class ClientWriter;
+template <class W, class R>
+class ClientReaderWriter;
+namespace internal {
+template <class InputMessage, class OutputMessage>
+class CallbackUnaryCallImpl;
+template <class R>
+class ClientAsyncReaderFactory;
+template <class W>
+class ClientAsyncWriterFactory;
+template <class W, class R>
+class ClientAsyncReaderWriterFactory;
+class ClientAsyncResponseReaderHelper;
+template <class W, class R>
+class ClientCallbackReaderWriterFactory;
+template <class R>
+class ClientCallbackReaderFactory;
+template <class W>
+class ClientCallbackWriterFactory;
+class ClientCallbackUnaryFactory;
+}  // namespace internal
+
+class ChannelInterface;
+class ClientContext;
+class CompletionQueue;
+
+namespace experimental {
+class DelegatingChannel;
+}
+
+namespace internal {
+class Call;
+class CallOpSetInterface;
+class RpcMethod;
+class InterceptedChannel;
+template <class InputMessage, class OutputMessage>
+class BlockingUnaryCallImpl;
+}  // namespace internal
+
+/// Codegen interface for \a grpc::Channel.
+class ChannelInterface {
+ public:
+  virtual ~ChannelInterface() {}
+  /// Get the current channel state. If the channel is in IDLE and
+  /// \a try_to_connect is set to true, try to connect.
+  virtual grpc_connectivity_state GetState(bool try_to_connect) = 0;
+
+  /// Return the \a tag on \a cq when the channel state is changed or \a
+  /// deadline expires. \a GetState needs to called to get the current state.
+  template <typename T>
+  void NotifyOnStateChange(grpc_connectivity_state last_observed, T deadline,
+                           grpc::CompletionQueue* cq, void* tag) {
+    TimePoint<T> deadline_tp(deadline);
+    NotifyOnStateChangeImpl(last_observed, deadline_tp.raw_time(), cq, tag);
+  }
+
+  /// Blocking wait for channel state change or \a deadline expiration.
+  /// \a GetState needs to called to get the current state.
+  template <typename T>
+  bool WaitForStateChange(grpc_connectivity_state last_observed, T deadline) {
+    TimePoint<T> deadline_tp(deadline);
+    return WaitForStateChangeImpl(last_observed, deadline_tp.raw_time());
+  }
+
+  /// Wait for this channel to be connected
+  template <typename T>
+  bool WaitForConnected(T deadline) {
+    grpc_connectivity_state state;
+    while ((state = GetState(true)) != GRPC_CHANNEL_READY) {
+      if (!WaitForStateChange(state, deadline)) return false;
+    }
+    return true;
+  }
+
+ private:
+  template <class R>
+  friend class grpc::ClientReader;
+  template <class W>
+  friend class grpc::ClientWriter;
+  template <class W, class R>
+  friend class grpc::ClientReaderWriter;
+  template <class R>
+  friend class grpc::internal::ClientAsyncReaderFactory;
+  template <class W>
+  friend class grpc::internal::ClientAsyncWriterFactory;
+  template <class W, class R>
+  friend class grpc::internal::ClientAsyncReaderWriterFactory;
+  friend class grpc::internal::ClientAsyncResponseReaderHelper;
+  template <class W, class R>
+  friend class grpc::internal::ClientCallbackReaderWriterFactory;
+  template <class R>
+  friend class grpc::internal::ClientCallbackReaderFactory;
+  template <class W>
+  friend class grpc::internal::ClientCallbackWriterFactory;
+  friend class grpc::internal::ClientCallbackUnaryFactory;
+  template <class InputMessage, class OutputMessage>
+  friend class grpc::internal::BlockingUnaryCallImpl;
+  template <class InputMessage, class OutputMessage>
+  friend class grpc::internal::CallbackUnaryCallImpl;
+  friend class grpc::internal::RpcMethod;
+  friend class grpc::experimental::DelegatingChannel;
+  friend class grpc::internal::InterceptedChannel;
+  virtual internal::Call CreateCall(const internal::RpcMethod& method,
+                                    grpc::ClientContext* context,
+                                    grpc::CompletionQueue* cq) = 0;
+  virtual void PerformOpsOnCall(internal::CallOpSetInterface* ops,
+                                internal::Call* call) = 0;
+  virtual void* RegisterMethod(const char* method) = 0;
+  virtual void NotifyOnStateChangeImpl(grpc_connectivity_state last_observed,
+                                       gpr_timespec deadline,
+                                       grpc::CompletionQueue* cq,
+                                       void* tag) = 0;
+  virtual bool WaitForStateChangeImpl(grpc_connectivity_state last_observed,
+                                      gpr_timespec deadline) = 0;
+
+  // EXPERIMENTAL
+  // This is needed to keep codegen_test_minimal happy. InterceptedChannel needs
+  // to make use of this but can't directly call Channel's implementation
+  // because of the test.
+  // Returns an empty Call object (rather than being pure) since this is a new
+  // method and adding a new pure method to an interface would be a breaking
+  // change (even though this is private and non-API)
+  virtual internal::Call CreateCallInternal(
+      const internal::RpcMethod& /*method*/, grpc::ClientContext* /*context*/,
+      grpc::CompletionQueue* /*cq*/, size_t /*interceptor_pos*/) {
+    return internal::Call();
+  }
+
+  // A method to get the callbackable completion queue associated with this
+  // channel. If the return value is nullptr, this channel doesn't support
+  // callback operations.
+  // TODO(vjpai): Consider a better default like using a global CQ
+  // Returns nullptr (rather than being pure) since this is a post-1.0 method
+  // and adding a new pure method to an interface would be a breaking change
+  // (even though this is private and non-API)
+  virtual grpc::CompletionQueue* CallbackCQ() { return nullptr; }
+};
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CHANNEL_INTERFACE_H

Pods/gRPC-C++/include/grpcpp/impl/client_unary_call.h

@@ -0,0 +1,102 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CLIENT_UNARY_CALL_H
+#define GRPCPP_IMPL_CLIENT_UNARY_CALL_H
+
+#include <grpcpp/impl/call.h>
+#include <grpcpp/impl/call_op_set.h>
+#include <grpcpp/impl/channel_interface.h>
+#include <grpcpp/support/config.h>
+#include <grpcpp/support/status.h>
+
+namespace grpc {
+
+class ClientContext;
+namespace internal {
+class RpcMethod;
+
+/// Wrapper that performs a blocking unary call. May optionally specify the base
+/// class of the Request and Response so that the internal calls and structures
+/// below this may be based on those base classes and thus achieve code reuse
+/// across different RPCs (e.g., for protobuf, MessageLite would be a base
+/// class).
+template <class InputMessage, class OutputMessage,
+          class BaseInputMessage = InputMessage,
+          class BaseOutputMessage = OutputMessage>
+Status BlockingUnaryCall(ChannelInterface* channel, const RpcMethod& method,
+                         grpc::ClientContext* context,
+                         const InputMessage& request, OutputMessage* result) {
+  static_assert(std::is_base_of<BaseInputMessage, InputMessage>::value,
+                "Invalid input message specification");
+  static_assert(std::is_base_of<BaseOutputMessage, OutputMessage>::value,
+                "Invalid output message specification");
+  return BlockingUnaryCallImpl<BaseInputMessage, BaseOutputMessage>(
+             channel, method, context, request, result)
+      .status();
+}
+
+template <class InputMessage, class OutputMessage>
+class BlockingUnaryCallImpl {
+ public:
+  BlockingUnaryCallImpl(ChannelInterface* channel, const RpcMethod& method,
+                        grpc::ClientContext* context,
+                        const InputMessage& request, OutputMessage* result) {
+    grpc::CompletionQueue cq(grpc_completion_queue_attributes{
+        GRPC_CQ_CURRENT_VERSION, GRPC_CQ_PLUCK, GRPC_CQ_DEFAULT_POLLING,
+        nullptr});  // Pluckable completion queue
+    grpc::internal::Call call(channel->CreateCall(method, context, &cq));
+    CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
+              CallOpRecvInitialMetadata, CallOpRecvMessage<OutputMessage>,
+              CallOpClientSendClose, CallOpClientRecvStatus>
+        ops;
+    status_ = ops.SendMessagePtr(&request);
+    if (!status_.ok()) {
+      return;
+    }
+    ops.SendInitialMetadata(&context->send_initial_metadata_,
+                            context->initial_metadata_flags());
+    ops.RecvInitialMetadata(context);
+    ops.RecvMessage(result);
+    ops.AllowNoMessage();
+    ops.ClientSendClose();
+    ops.ClientRecvStatus(context, &status_);
+    call.PerformOps(&ops);
+    cq.Pluck(&ops);
+    // Some of the ops might fail. If the ops fail in the core layer, status
+    // would reflect the error. But, if the ops fail in the C++ layer, the
+    // status would still be the same as the one returned by gRPC Core. This can
+    // happen if deserialization of the message fails.
+    // TODO(yashykt): If deserialization fails, but the status received is OK,
+    // then it might be a good idea to change the status to something better
+    // than StatusCode::UNIMPLEMENTED to reflect this.
+    if (!ops.got_message && status_.ok()) {
+      status_ = Status(StatusCode::UNIMPLEMENTED,
+                       "No message returned for unary request");
+    }
+  }
+  Status status() { return status_; }
+
+ private:
+  Status status_;
+};
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CLIENT_UNARY_CALL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/async_generic_service.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_ASYNC_GENERIC_SERVICE_H
+#define GRPCPP_IMPL_CODEGEN_ASYNC_GENERIC_SERVICE_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/generic/async_generic_service.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_ASYNC_GENERIC_SERVICE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/async_stream.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_ASYNC_STREAM_H
+#define GRPCPP_IMPL_CODEGEN_ASYNC_STREAM_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/async_stream.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_ASYNC_STREAM_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/async_unary_call.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_ASYNC_UNARY_CALL_H
+#define GRPCPP_IMPL_CODEGEN_ASYNC_UNARY_CALL_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/async_unary_call.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_ASYNC_UNARY_CALL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/byte_buffer.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_BYTE_BUFFER_H
+#define GRPCPP_IMPL_CODEGEN_BYTE_BUFFER_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/byte_buffer.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_BYTE_BUFFER_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/call.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+#ifndef GRPCPP_IMPL_CODEGEN_CALL_H
+#define GRPCPP_IMPL_CODEGEN_CALL_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/call.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CALL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/call_hook.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CALL_HOOK_H
+#define GRPCPP_IMPL_CODEGEN_CALL_HOOK_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/call_hook.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CALL_HOOK_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/call_op_set.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CALL_OP_SET_H
+#define GRPCPP_IMPL_CODEGEN_CALL_OP_SET_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/call_op_set.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CALL_OP_SET_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/call_op_set_interface.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CALL_OP_SET_INTERFACE_H
+#define GRPCPP_IMPL_CODEGEN_CALL_OP_SET_INTERFACE_H
+
+// IWYU pragma: private
+
+#include <grpcpp/impl/call_op_set_interface.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CALL_OP_SET_INTERFACE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/callback_common.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CALLBACK_COMMON_H
+#define GRPCPP_IMPL_CODEGEN_CALLBACK_COMMON_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/callback_common.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CALLBACK_COMMON_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/channel_interface.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CHANNEL_INTERFACE_H
+#define GRPCPP_IMPL_CODEGEN_CHANNEL_INTERFACE_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/channel_interface.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CHANNEL_INTERFACE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/client_callback.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CLIENT_CALLBACK_H
+#define GRPCPP_IMPL_CODEGEN_CLIENT_CALLBACK_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/client_callback.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CLIENT_CALLBACK_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/client_context.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CLIENT_CONTEXT_H
+#define GRPCPP_IMPL_CODEGEN_CLIENT_CONTEXT_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/client_context.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CLIENT_CONTEXT_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/client_interceptor.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CLIENT_INTERCEPTOR_H
+#define GRPCPP_IMPL_CODEGEN_CLIENT_INTERCEPTOR_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/client_interceptor.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CLIENT_INTERCEPTOR_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/client_unary_call.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CLIENT_UNARY_CALL_H
+#define GRPCPP_IMPL_CODEGEN_CLIENT_UNARY_CALL_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/client_unary_call.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CLIENT_UNARY_CALL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/completion_queue.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015-2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_COMPLETION_QUEUE_H
+#define GRPCPP_IMPL_CODEGEN_COMPLETION_QUEUE_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/completion_queue.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_COMPLETION_QUEUE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/completion_queue_tag.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_COMPLETION_QUEUE_TAG_H
+#define GRPCPP_IMPL_CODEGEN_COMPLETION_QUEUE_TAG_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/completion_queue_tag.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_COMPLETION_QUEUE_TAG_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/config.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CONFIG_H
+#define GRPCPP_IMPL_CODEGEN_CONFIG_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/config.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CONFIG_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/create_auth_context.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_CREATE_AUTH_CONTEXT_H
+#define GRPCPP_IMPL_CODEGEN_CREATE_AUTH_CONTEXT_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/create_auth_context.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_CREATE_AUTH_CONTEXT_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/delegating_channel.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_DELEGATING_CHANNEL_H
+#define GRPCPP_IMPL_CODEGEN_DELEGATING_CHANNEL_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/delegating_channel.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_DELEGATING_CHANNEL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/intercepted_channel.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_INTERCEPTED_CHANNEL_H
+#define GRPCPP_IMPL_CODEGEN_INTERCEPTED_CHANNEL_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/intercepted_channel.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_INTERCEPTED_CHANNEL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/interceptor.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_INTERCEPTOR_H
+#define GRPCPP_IMPL_CODEGEN_INTERCEPTOR_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/interceptor.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_INTERCEPTOR_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/interceptor_common.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_INTERCEPTOR_COMMON_H
+#define GRPCPP_IMPL_CODEGEN_INTERCEPTOR_COMMON_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/interceptor_common.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_INTERCEPTOR_COMMON_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/message_allocator.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_MESSAGE_ALLOCATOR_H
+#define GRPCPP_IMPL_CODEGEN_MESSAGE_ALLOCATOR_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/message_allocator.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_MESSAGE_ALLOCATOR_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/metadata_map.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_METADATA_MAP_H
+#define GRPCPP_IMPL_CODEGEN_METADATA_MAP_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/metadata_map.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_METADATA_MAP_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/method_handler.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_METHOD_HANDLER_H
+#define GRPCPP_IMPL_CODEGEN_METHOD_HANDLER_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/method_handler.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_METHOD_HANDLER_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/method_handler_impl.h

@@ -0,0 +1,24 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_METHOD_HANDLER_IMPL_H
+#define GRPCPP_IMPL_CODEGEN_METHOD_HANDLER_IMPL_H
+
+// IWYU pragma: private
+
+#endif  // GRPCPP_IMPL_CODEGEN_METHOD_HANDLER_IMPL_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/rpc_method.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_RPC_METHOD_H
+#define GRPCPP_IMPL_CODEGEN_RPC_METHOD_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/rpc_method.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_RPC_METHOD_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/rpc_service_method.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_RPC_SERVICE_METHOD_H
+#define GRPCPP_IMPL_CODEGEN_RPC_SERVICE_METHOD_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/rpc_service_method.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_RPC_SERVICE_METHOD_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/security/auth_context.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SECURITY_AUTH_CONTEXT_H
+#define GRPCPP_IMPL_CODEGEN_SECURITY_AUTH_CONTEXT_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/security/auth_context.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SECURITY_AUTH_CONTEXT_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/serialization_traits.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERIALIZATION_TRAITS_H
+#define GRPCPP_IMPL_CODEGEN_SERIALIZATION_TRAITS_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/serialization_traits.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERIALIZATION_TRAITS_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/server_callback.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERVER_CALLBACK_H
+#define GRPCPP_IMPL_CODEGEN_SERVER_CALLBACK_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/server_callback.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERVER_CALLBACK_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/server_callback_handlers.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERVER_CALLBACK_HANDLERS_H
+#define GRPCPP_IMPL_CODEGEN_SERVER_CALLBACK_HANDLERS_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/server_callback_handlers.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERVER_CALLBACK_HANDLERS_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/server_context.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERVER_CONTEXT_H
+#define GRPCPP_IMPL_CODEGEN_SERVER_CONTEXT_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/server_context.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERVER_CONTEXT_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/server_interceptor.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERVER_INTERCEPTOR_H
+#define GRPCPP_IMPL_CODEGEN_SERVER_INTERCEPTOR_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/server_interceptor.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERVER_INTERCEPTOR_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/server_interface.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERVER_INTERFACE_H
+#define GRPCPP_IMPL_CODEGEN_SERVER_INTERFACE_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/server_interface.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERVER_INTERFACE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/service_type.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SERVICE_TYPE_H
+#define GRPCPP_IMPL_CODEGEN_SERVICE_TYPE_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/service_type.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SERVICE_TYPE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/slice.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SLICE_H
+#define GRPCPP_IMPL_CODEGEN_SLICE_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/slice.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SLICE_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/status.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_STATUS_H
+#define GRPCPP_IMPL_CODEGEN_STATUS_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/status.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_STATUS_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/status_code_enum.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_STATUS_CODE_ENUM_H
+#define GRPCPP_IMPL_CODEGEN_STATUS_CODE_ENUM_H
+
+// IWYU pragma: private, include <grpcpp/support/status.h>
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/status_code_enum.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_STATUS_CODE_ENUM_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/string_ref.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_STRING_REF_H
+#define GRPCPP_IMPL_CODEGEN_STRING_REF_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/string_ref.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_STRING_REF_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/stub_options.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_STUB_OPTIONS_H
+#define GRPCPP_IMPL_CODEGEN_STUB_OPTIONS_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/stub_options.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_STUB_OPTIONS_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/sync.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SYNC_H
+#define GRPCPP_IMPL_CODEGEN_SYNC_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/impl/sync.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SYNC_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/sync_stream.h

@@ -0,0 +1,26 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_SYNC_STREAM_H
+#define GRPCPP_IMPL_CODEGEN_SYNC_STREAM_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/sync_stream.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_SYNC_STREAM_H

Pods/gRPC-C++/include/grpcpp/impl/codegen/time.h

@@ -0,0 +1,27 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CODEGEN_TIME_H
+#define GRPCPP_IMPL_CODEGEN_TIME_H
+
+// IWYU pragma: private
+
+/// TODO(chengyuc): Remove this file after solving compatibility.
+#include <grpcpp/support/time.h>
+
+#endif  // GRPCPP_IMPL_CODEGEN_TIME_H

Pods/gRPC-C++/include/grpcpp/impl/completion_queue_tag.h

@@ -0,0 +1,54 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_COMPLETION_QUEUE_TAG_H
+#define GRPCPP_IMPL_COMPLETION_QUEUE_TAG_H
+
+namespace grpc {
+
+namespace internal {
+/// An interface allowing implementors to process and filter event tags.
+class CompletionQueueTag {
+ public:
+  virtual ~CompletionQueueTag() {}
+
+  /// FinalizeResult must be called before informing user code that the
+  /// operation bound to the underlying core completion queue tag has
+  /// completed. In practice, this means:
+  ///
+  ///   1. For the sync API - before returning from Pluck
+  ///   2. For the CQ-based async API - before returning from Next
+  ///   3. For the callback-based API - before invoking the user callback
+  ///
+  /// This is the method that translates from core-side tag/status to
+  /// C++ API-observable tag/status.
+  ///
+  /// The return value is the status of the operation (returning status is the
+  /// general behavior of this function). If this function returns false, the
+  /// tag is dropped and not returned from the completion queue: this concept is
+  /// for events that are observed at core but not requested by the user
+  /// application (e.g., server shutdown, for server unimplemented method
+  /// responses, or for cases where a server-side RPC doesn't have a completion
+  /// notification registered using AsyncNotifyWhenDone)
+  virtual bool FinalizeResult(void** tag, bool* status) = 0;
+};
+}  // namespace internal
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_COMPLETION_QUEUE_TAG_H

Pods/gRPC-C++/include/grpcpp/impl/create_auth_context.h

@@ -0,0 +1,34 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_CREATE_AUTH_CONTEXT_H
+#define GRPCPP_IMPL_CREATE_AUTH_CONTEXT_H
+
+#include <memory>
+
+#include <grpc/impl/grpc_types.h>
+#include <grpcpp/security/auth_context.h>
+
+namespace grpc {
+
+/// TODO(ctiller): not sure we want to make this a permanent thing
+std::shared_ptr<const AuthContext> CreateAuthContext(grpc_call* call);
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CREATE_AUTH_CONTEXT_H

Pods/gRPC-C++/include/grpcpp/impl/delegating_channel.h

@@ -0,0 +1,91 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_DELEGATING_CHANNEL_H
+#define GRPCPP_IMPL_DELEGATING_CHANNEL_H
+
+#include <memory>
+
+#include <grpcpp/impl/channel_interface.h>
+
+namespace grpc {
+namespace experimental {
+
+class DelegatingChannel : public grpc::ChannelInterface {
+ public:
+  ~DelegatingChannel() override {}
+
+  explicit DelegatingChannel(
+      std::shared_ptr<grpc::ChannelInterface> delegate_channel)
+      : delegate_channel_(delegate_channel) {}
+
+  grpc_connectivity_state GetState(bool try_to_connect) override {
+    return delegate_channel()->GetState(try_to_connect);
+  }
+
+  std::shared_ptr<grpc::ChannelInterface> delegate_channel() {
+    return delegate_channel_;
+  }
+
+ private:
+  internal::Call CreateCall(const internal::RpcMethod& method,
+                            ClientContext* context,
+                            grpc::CompletionQueue* cq) final {
+    return delegate_channel()->CreateCall(method, context, cq);
+  }
+
+  void PerformOpsOnCall(internal::CallOpSetInterface* ops,
+                        internal::Call* call) final {
+    delegate_channel()->PerformOpsOnCall(ops, call);
+  }
+
+  void* RegisterMethod(const char* method) final {
+    return delegate_channel()->RegisterMethod(method);
+  }
+
+  void NotifyOnStateChangeImpl(grpc_connectivity_state last_observed,
+                               gpr_timespec deadline, grpc::CompletionQueue* cq,
+                               void* tag) override {
+    delegate_channel()->NotifyOnStateChangeImpl(last_observed, deadline, cq,
+                                                tag);
+  }
+
+  bool WaitForStateChangeImpl(grpc_connectivity_state last_observed,
+                              gpr_timespec deadline) override {
+    return delegate_channel()->WaitForStateChangeImpl(last_observed, deadline);
+  }
+
+  internal::Call CreateCallInternal(const internal::RpcMethod& method,
+                                    ClientContext* context,
+                                    grpc::CompletionQueue* cq,
+                                    size_t interceptor_pos) final {
+    return delegate_channel()->CreateCallInternal(method, context, cq,
+                                                  interceptor_pos);
+  }
+
+  grpc::CompletionQueue* CallbackCQ() final {
+    return delegate_channel()->CallbackCQ();
+  }
+
+  std::shared_ptr<grpc::ChannelInterface> delegate_channel_;
+};
+
+}  // namespace experimental
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_DELEGATING_CHANNEL_H

Pods/gRPC-C++/include/grpcpp/impl/grpc_library.h

@@ -0,0 +1,53 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_GRPC_LIBRARY_H
+#define GRPCPP_IMPL_GRPC_LIBRARY_H
+
+#include <iostream>
+
+#include <grpc/grpc.h>
+#include <grpcpp/impl/codegen/config.h>
+
+namespace grpc {
+
+namespace internal {
+
+/// Classes that require gRPC to be initialized should inherit from this class.
+class GrpcLibrary {
+ public:
+  explicit GrpcLibrary(bool call_grpc_init = true) : grpc_init_called_(false) {
+    if (call_grpc_init) {
+      grpc_init();
+      grpc_init_called_ = true;
+    }
+  }
+  virtual ~GrpcLibrary() {
+    if (grpc_init_called_) {
+      grpc_shutdown();
+    }
+  }
+
+ private:
+  bool grpc_init_called_;
+};
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_GRPC_LIBRARY_H

Pods/gRPC-C++/include/grpcpp/impl/intercepted_channel.h

@@ -0,0 +1,83 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_INTERCEPTED_CHANNEL_H
+#define GRPCPP_IMPL_INTERCEPTED_CHANNEL_H
+
+#include <grpcpp/impl/channel_interface.h>
+
+namespace grpc {
+class CompletionQueue;
+
+namespace internal {
+
+class InterceptorBatchMethodsImpl;
+
+/// An InterceptedChannel is available to client Interceptors. An
+/// InterceptedChannel is unique to an interceptor, and when an RPC is started
+/// on this channel, only those interceptors that come after this interceptor
+/// see the RPC.
+class InterceptedChannel : public ChannelInterface {
+ public:
+  ~InterceptedChannel() override { channel_ = nullptr; }
+
+  /// Get the current channel state. If the channel is in IDLE and
+  /// \a try_to_connect is set to true, try to connect.
+  grpc_connectivity_state GetState(bool try_to_connect) override {
+    return channel_->GetState(try_to_connect);
+  }
+
+ private:
+  InterceptedChannel(ChannelInterface* channel, size_t pos)
+      : channel_(channel), interceptor_pos_(pos) {}
+
+  Call CreateCall(const RpcMethod& method, grpc::ClientContext* context,
+                  grpc::CompletionQueue* cq) override {
+    return channel_->CreateCallInternal(method, context, cq, interceptor_pos_);
+  }
+
+  void PerformOpsOnCall(CallOpSetInterface* ops, Call* call) override {
+    return channel_->PerformOpsOnCall(ops, call);
+  }
+  void* RegisterMethod(const char* method) override {
+    return channel_->RegisterMethod(method);
+  }
+
+  void NotifyOnStateChangeImpl(grpc_connectivity_state last_observed,
+                               gpr_timespec deadline, grpc::CompletionQueue* cq,
+                               void* tag) override {
+    return channel_->NotifyOnStateChangeImpl(last_observed, deadline, cq, tag);
+  }
+  bool WaitForStateChangeImpl(grpc_connectivity_state last_observed,
+                              gpr_timespec deadline) override {
+    return channel_->WaitForStateChangeImpl(last_observed, deadline);
+  }
+
+  grpc::CompletionQueue* CallbackCQ() override {
+    return channel_->CallbackCQ();
+  }
+
+  ChannelInterface* channel_;
+  size_t interceptor_pos_;
+
+  friend class InterceptorBatchMethodsImpl;
+};
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_INTERCEPTED_CHANNEL_H

Pods/gRPC-C++/include/grpcpp/impl/interceptor_common.h

@@ -0,0 +1,536 @@
+//
+//
+// Copyright 2018 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_INTERCEPTOR_COMMON_H
+#define GRPCPP_IMPL_INTERCEPTOR_COMMON_H
+
+#include <array>
+#include <functional>
+
+#include <grpc/impl/grpc_types.h>
+#include <grpc/support/log.h>
+#include <grpcpp/impl/call.h>
+#include <grpcpp/impl/call_op_set_interface.h>
+#include <grpcpp/impl/intercepted_channel.h>
+#include <grpcpp/support/client_interceptor.h>
+#include <grpcpp/support/server_interceptor.h>
+
+namespace grpc {
+namespace internal {
+
+class InterceptorBatchMethodsImpl
+    : public experimental::InterceptorBatchMethods {
+ public:
+  InterceptorBatchMethodsImpl() {
+    for (auto i = static_cast<experimental::InterceptionHookPoints>(0);
+         i < experimental::InterceptionHookPoints::NUM_INTERCEPTION_HOOKS;
+         i = static_cast<experimental::InterceptionHookPoints>(
+             static_cast<size_t>(i) + 1)) {
+      hooks_[static_cast<size_t>(i)] = false;
+    }
+  }
+
+  ~InterceptorBatchMethodsImpl() override {}
+
+  bool QueryInterceptionHookPoint(
+      experimental::InterceptionHookPoints type) override {
+    return hooks_[static_cast<size_t>(type)];
+  }
+
+  void Proceed() override {
+    if (call_->client_rpc_info() != nullptr) {
+      return ProceedClient();
+    }
+    GPR_ASSERT(call_->server_rpc_info() != nullptr);
+    ProceedServer();
+  }
+
+  void Hijack() override {
+    // Only the client can hijack when sending down initial metadata
+    GPR_ASSERT(!reverse_ && ops_ != nullptr &&
+               call_->client_rpc_info() != nullptr);
+    // It is illegal to call Hijack twice
+    GPR_ASSERT(!ran_hijacking_interceptor_);
+    auto* rpc_info = call_->client_rpc_info();
+    rpc_info->hijacked_ = true;
+    rpc_info->hijacked_interceptor_ = current_interceptor_index_;
+    ClearHookPoints();
+    ops_->SetHijackingState();
+    ran_hijacking_interceptor_ = true;
+    rpc_info->RunInterceptor(this, current_interceptor_index_);
+  }
+
+  void AddInterceptionHookPoint(experimental::InterceptionHookPoints type) {
+    hooks_[static_cast<size_t>(type)] = true;
+  }
+
+  ByteBuffer* GetSerializedSendMessage() override {
+    GPR_ASSERT(orig_send_message_ != nullptr);
+    if (*orig_send_message_ != nullptr) {
+      GPR_ASSERT(serializer_(*orig_send_message_).ok());
+      *orig_send_message_ = nullptr;
+    }
+    return send_message_;
+  }
+
+  const void* GetSendMessage() override {
+    GPR_ASSERT(orig_send_message_ != nullptr);
+    return *orig_send_message_;
+  }
+
+  void ModifySendMessage(const void* message) override {
+    GPR_ASSERT(orig_send_message_ != nullptr);
+    *orig_send_message_ = message;
+  }
+
+  bool GetSendMessageStatus() override { return !*fail_send_message_; }
+
+  std::multimap<std::string, std::string>* GetSendInitialMetadata() override {
+    return send_initial_metadata_;
+  }
+
+  Status GetSendStatus() override {
+    return Status(static_cast<StatusCode>(*code_), *error_message_,
+                  *error_details_);
+  }
+
+  void ModifySendStatus(const Status& status) override {
+    *code_ = static_cast<grpc_status_code>(status.error_code());
+    *error_details_ = status.error_details();
+    *error_message_ = status.error_message();
+  }
+
+  std::multimap<std::string, std::string>* GetSendTrailingMetadata() override {
+    return send_trailing_metadata_;
+  }
+
+  void* GetRecvMessage() override { return recv_message_; }
+
+  std::multimap<grpc::string_ref, grpc::string_ref>* GetRecvInitialMetadata()
+      override {
+    return recv_initial_metadata_->map();
+  }
+
+  Status* GetRecvStatus() override { return recv_status_; }
+
+  void FailHijackedSendMessage() override {
+    GPR_ASSERT(hooks_[static_cast<size_t>(
+        experimental::InterceptionHookPoints::PRE_SEND_MESSAGE)]);
+    *fail_send_message_ = true;
+  }
+
+  std::multimap<grpc::string_ref, grpc::string_ref>* GetRecvTrailingMetadata()
+      override {
+    return recv_trailing_metadata_->map();
+  }
+
+  void SetSendMessage(ByteBuffer* buf, const void** msg,
+                      bool* fail_send_message,
+                      std::function<Status(const void*)> serializer) {
+    send_message_ = buf;
+    orig_send_message_ = msg;
+    fail_send_message_ = fail_send_message;
+    serializer_ = serializer;
+  }
+
+  void SetSendInitialMetadata(
+      std::multimap<std::string, std::string>* metadata) {
+    send_initial_metadata_ = metadata;
+  }
+
+  void SetSendStatus(grpc_status_code* code, std::string* error_details,
+                     std::string* error_message) {
+    code_ = code;
+    error_details_ = error_details;
+    error_message_ = error_message;
+  }
+
+  void SetSendTrailingMetadata(
+      std::multimap<std::string, std::string>* metadata) {
+    send_trailing_metadata_ = metadata;
+  }
+
+  void SetRecvMessage(void* message, bool* hijacked_recv_message_failed) {
+    recv_message_ = message;
+    hijacked_recv_message_failed_ = hijacked_recv_message_failed;
+  }
+
+  void SetRecvInitialMetadata(MetadataMap* map) {
+    recv_initial_metadata_ = map;
+  }
+
+  void SetRecvStatus(Status* status) { recv_status_ = status; }
+
+  void SetRecvTrailingMetadata(MetadataMap* map) {
+    recv_trailing_metadata_ = map;
+  }
+
+  std::unique_ptr<ChannelInterface> GetInterceptedChannel() override {
+    auto* info = call_->client_rpc_info();
+    if (info == nullptr) {
+      return std::unique_ptr<ChannelInterface>(nullptr);
+    }
+    // The intercepted channel starts from the interceptor just after the
+    // current interceptor
+    return std::unique_ptr<ChannelInterface>(new InterceptedChannel(
+        info->channel(), current_interceptor_index_ + 1));
+  }
+
+  void FailHijackedRecvMessage() override {
+    GPR_ASSERT(hooks_[static_cast<size_t>(
+        experimental::InterceptionHookPoints::PRE_RECV_MESSAGE)]);
+    *hijacked_recv_message_failed_ = true;
+  }
+
+  // Clears all state
+  void ClearState() {
+    reverse_ = false;
+    ran_hijacking_interceptor_ = false;
+    ClearHookPoints();
+  }
+
+  // Prepares for Post_recv operations
+  void SetReverse() {
+    reverse_ = true;
+    ran_hijacking_interceptor_ = false;
+    ClearHookPoints();
+  }
+
+  // This needs to be set before interceptors are run
+  void SetCall(Call* call) { call_ = call; }
+
+  // This needs to be set before interceptors are run using RunInterceptors().
+  // Alternatively, RunInterceptors(std::function<void(void)> f) can be used.
+  void SetCallOpSetInterface(CallOpSetInterface* ops) { ops_ = ops; }
+
+  // SetCall should have been called before this.
+  // Returns true if the interceptors list is empty
+  bool InterceptorsListEmpty() {
+    auto* client_rpc_info = call_->client_rpc_info();
+    if (client_rpc_info != nullptr) {
+      return client_rpc_info->interceptors_.empty();
+    }
+
+    auto* server_rpc_info = call_->server_rpc_info();
+    return server_rpc_info == nullptr || server_rpc_info->interceptors_.empty();
+  }
+
+  // This should be used only by subclasses of CallOpSetInterface. SetCall and
+  // SetCallOpSetInterface should have been called before this. After all the
+  // interceptors are done running, either ContinueFillOpsAfterInterception or
+  // ContinueFinalizeOpsAfterInterception will be called. Note that neither of
+  // them is invoked if there were no interceptors registered.
+  bool RunInterceptors() {
+    GPR_ASSERT(ops_);
+    auto* client_rpc_info = call_->client_rpc_info();
+    if (client_rpc_info != nullptr) {
+      if (client_rpc_info->interceptors_.empty()) {
+        return true;
+      } else {
+        RunClientInterceptors();
+        return false;
+      }
+    }
+
+    auto* server_rpc_info = call_->server_rpc_info();
+    if (server_rpc_info == nullptr || server_rpc_info->interceptors_.empty()) {
+      return true;
+    }
+    RunServerInterceptors();
+    return false;
+  }
+
+  // Returns true if no interceptors are run. Returns false otherwise if there
+  // are interceptors registered. After the interceptors are done running \a f
+  // will be invoked. This is to be used only by BaseAsyncRequest and
+  // SyncRequest.
+  bool RunInterceptors(std::function<void(void)> f) {
+    // This is used only by the server for initial call request
+    GPR_ASSERT(reverse_ == true);
+    GPR_ASSERT(call_->client_rpc_info() == nullptr);
+    auto* server_rpc_info = call_->server_rpc_info();
+    if (server_rpc_info == nullptr || server_rpc_info->interceptors_.empty()) {
+      return true;
+    }
+    callback_ = std::move(f);
+    RunServerInterceptors();
+    return false;
+  }
+
+ private:
+  void RunClientInterceptors() {
+    auto* rpc_info = call_->client_rpc_info();
+    if (!reverse_) {
+      current_interceptor_index_ = 0;
+    } else {
+      if (rpc_info->hijacked_) {
+        current_interceptor_index_ = rpc_info->hijacked_interceptor_;
+      } else {
+        current_interceptor_index_ = rpc_info->interceptors_.size() - 1;
+      }
+    }
+    rpc_info->RunInterceptor(this, current_interceptor_index_);
+  }
+
+  void RunServerInterceptors() {
+    auto* rpc_info = call_->server_rpc_info();
+    if (!reverse_) {
+      current_interceptor_index_ = 0;
+    } else {
+      current_interceptor_index_ = rpc_info->interceptors_.size() - 1;
+    }
+    rpc_info->RunInterceptor(this, current_interceptor_index_);
+  }
+
+  void ProceedClient() {
+    auto* rpc_info = call_->client_rpc_info();
+    if (rpc_info->hijacked_ && !reverse_ &&
+        current_interceptor_index_ == rpc_info->hijacked_interceptor_ &&
+        !ran_hijacking_interceptor_) {
+      // We now need to provide hijacked recv ops to this interceptor
+      ClearHookPoints();
+      ops_->SetHijackingState();
+      ran_hijacking_interceptor_ = true;
+      rpc_info->RunInterceptor(this, current_interceptor_index_);
+      return;
+    }
+    if (!reverse_) {
+      current_interceptor_index_++;
+      // We are going down the stack of interceptors
+      if (current_interceptor_index_ < rpc_info->interceptors_.size()) {
+        if (rpc_info->hijacked_ &&
+            current_interceptor_index_ > rpc_info->hijacked_interceptor_) {
+          // This is a hijacked RPC and we are done with hijacking
+          ops_->ContinueFillOpsAfterInterception();
+        } else {
+          rpc_info->RunInterceptor(this, current_interceptor_index_);
+        }
+      } else {
+        // we are done running all the interceptors without any hijacking
+        ops_->ContinueFillOpsAfterInterception();
+      }
+    } else {
+      // We are going up the stack of interceptors
+      if (current_interceptor_index_ > 0) {
+        // Continue running interceptors
+        current_interceptor_index_--;
+        rpc_info->RunInterceptor(this, current_interceptor_index_);
+      } else {
+        // we are done running all the interceptors without any hijacking
+        ops_->ContinueFinalizeResultAfterInterception();
+      }
+    }
+  }
+
+  void ProceedServer() {
+    auto* rpc_info = call_->server_rpc_info();
+    if (!reverse_) {
+      current_interceptor_index_++;
+      if (current_interceptor_index_ < rpc_info->interceptors_.size()) {
+        return rpc_info->RunInterceptor(this, current_interceptor_index_);
+      } else if (ops_) {
+        return ops_->ContinueFillOpsAfterInterception();
+      }
+    } else {
+      // We are going up the stack of interceptors
+      if (current_interceptor_index_ > 0) {
+        // Continue running interceptors
+        current_interceptor_index_--;
+        return rpc_info->RunInterceptor(this, current_interceptor_index_);
+      } else if (ops_) {
+        return ops_->ContinueFinalizeResultAfterInterception();
+      }
+    }
+    GPR_ASSERT(callback_);
+    callback_();
+  }
+
+  void ClearHookPoints() {
+    for (auto i = static_cast<experimental::InterceptionHookPoints>(0);
+         i < experimental::InterceptionHookPoints::NUM_INTERCEPTION_HOOKS;
+         i = static_cast<experimental::InterceptionHookPoints>(
+             static_cast<size_t>(i) + 1)) {
+      hooks_[static_cast<size_t>(i)] = false;
+    }
+  }
+
+  std::array<bool,
+             static_cast<size_t>(
+                 experimental::InterceptionHookPoints::NUM_INTERCEPTION_HOOKS)>
+      hooks_;
+
+  size_t current_interceptor_index_ = 0;  // Current iterator
+  bool reverse_ = false;
+  bool ran_hijacking_interceptor_ = false;
+  Call* call_ = nullptr;  // The Call object is present along with CallOpSet
+                          // object/callback
+  CallOpSetInterface* ops_ = nullptr;
+  std::function<void(void)> callback_;
+
+  ByteBuffer* send_message_ = nullptr;
+  bool* fail_send_message_ = nullptr;
+  const void** orig_send_message_ = nullptr;
+  std::function<Status(const void*)> serializer_;
+
+  std::multimap<std::string, std::string>* send_initial_metadata_;
+
+  grpc_status_code* code_ = nullptr;
+  std::string* error_details_ = nullptr;
+  std::string* error_message_ = nullptr;
+
+  std::multimap<std::string, std::string>* send_trailing_metadata_ = nullptr;
+
+  void* recv_message_ = nullptr;
+  bool* hijacked_recv_message_failed_ = nullptr;
+
+  MetadataMap* recv_initial_metadata_ = nullptr;
+
+  Status* recv_status_ = nullptr;
+
+  MetadataMap* recv_trailing_metadata_ = nullptr;
+};
+
+// A special implementation of InterceptorBatchMethods to send a Cancel
+// notification down the interceptor stack
+class CancelInterceptorBatchMethods
+    : public experimental::InterceptorBatchMethods {
+ public:
+  bool QueryInterceptionHookPoint(
+      experimental::InterceptionHookPoints type) override {
+    return type == experimental::InterceptionHookPoints::PRE_SEND_CANCEL;
+  }
+
+  void Proceed() override {
+    // This is a no-op. For actual continuation of the RPC simply needs to
+    // return from the Intercept method
+  }
+
+  void Hijack() override {
+    // Only the client can hijack when sending down initial metadata
+    GPR_ASSERT(false &&
+               "It is illegal to call Hijack on a method which has a "
+               "Cancel notification");
+  }
+
+  ByteBuffer* GetSerializedSendMessage() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetSendMessage on a method which "
+               "has a Cancel notification");
+    return nullptr;
+  }
+
+  bool GetSendMessageStatus() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetSendMessageStatus on a method which "
+               "has a Cancel notification");
+    return false;
+  }
+
+  const void* GetSendMessage() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetOriginalSendMessage on a method which "
+               "has a Cancel notification");
+    return nullptr;
+  }
+
+  void ModifySendMessage(const void* /*message*/) override {
+    GPR_ASSERT(false &&
+               "It is illegal to call ModifySendMessage on a method which "
+               "has a Cancel notification");
+  }
+
+  std::multimap<std::string, std::string>* GetSendInitialMetadata() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetSendInitialMetadata on a "
+               "method which has a Cancel notification");
+    return nullptr;
+  }
+
+  Status GetSendStatus() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetSendStatus on a method which "
+               "has a Cancel notification");
+    return Status();
+  }
+
+  void ModifySendStatus(const Status& /*status*/) override {
+    GPR_ASSERT(false &&
+               "It is illegal to call ModifySendStatus on a method "
+               "which has a Cancel notification");
+  }
+
+  std::multimap<std::string, std::string>* GetSendTrailingMetadata() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetSendTrailingMetadata on a "
+               "method which has a Cancel notification");
+    return nullptr;
+  }
+
+  void* GetRecvMessage() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetRecvMessage on a method which "
+               "has a Cancel notification");
+    return nullptr;
+  }
+
+  std::multimap<grpc::string_ref, grpc::string_ref>* GetRecvInitialMetadata()
+      override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetRecvInitialMetadata on a "
+               "method which has a Cancel notification");
+    return nullptr;
+  }
+
+  Status* GetRecvStatus() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetRecvStatus on a method which "
+               "has a Cancel notification");
+    return nullptr;
+  }
+
+  std::multimap<grpc::string_ref, grpc::string_ref>* GetRecvTrailingMetadata()
+      override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetRecvTrailingMetadata on a "
+               "method which has a Cancel notification");
+    return nullptr;
+  }
+
+  std::unique_ptr<ChannelInterface> GetInterceptedChannel() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call GetInterceptedChannel on a "
+               "method which has a Cancel notification");
+    return std::unique_ptr<ChannelInterface>(nullptr);
+  }
+
+  void FailHijackedRecvMessage() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call FailHijackedRecvMessage on a "
+               "method which has a Cancel notification");
+  }
+
+  void FailHijackedSendMessage() override {
+    GPR_ASSERT(false &&
+               "It is illegal to call FailHijackedSendMessage on a "
+               "method which has a Cancel notification");
+  }
+};
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_INTERCEPTOR_COMMON_H

Pods/gRPC-C++/include/grpcpp/impl/metadata_map.h

@@ -0,0 +1,104 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_METADATA_MAP_H
+#define GRPCPP_IMPL_METADATA_MAP_H
+
+#include <map>
+
+#include <grpc/grpc.h>
+#include <grpc/support/log.h>
+#include <grpcpp/support/slice.h>
+
+namespace grpc {
+
+namespace internal {
+
+const char kBinaryErrorDetailsKey[] = "grpc-status-details-bin";
+
+class MetadataMap {
+ public:
+  MetadataMap() { Setup(); }
+
+  ~MetadataMap() { Destroy(); }
+
+  std::string GetBinaryErrorDetails() {
+    // if filled_, extract from the multimap for O(log(n))
+    if (filled_) {
+      auto iter = map_.find(kBinaryErrorDetailsKey);
+      if (iter != map_.end()) {
+        return std::string(iter->second.begin(), iter->second.length());
+      }
+    }
+    // if not yet filled, take the O(n) lookup to avoid allocating the
+    // multimap until it is requested.
+    // TODO(ncteisen): plumb this through core as a first class object, just
+    // like code and message.
+    else {
+      for (size_t i = 0; i < arr_.count; i++) {
+        if (strncmp(reinterpret_cast<const char*>(
+                        GRPC_SLICE_START_PTR(arr_.metadata[i].key)),
+                    kBinaryErrorDetailsKey,
+                    GRPC_SLICE_LENGTH(arr_.metadata[i].key)) == 0) {
+          return std::string(reinterpret_cast<const char*>(
+                                 GRPC_SLICE_START_PTR(arr_.metadata[i].value)),
+                             GRPC_SLICE_LENGTH(arr_.metadata[i].value));
+        }
+      }
+    }
+    return std::string();
+  }
+
+  std::multimap<grpc::string_ref, grpc::string_ref>* map() {
+    FillMap();
+    return &map_;
+  }
+  grpc_metadata_array* arr() { return &arr_; }
+
+  void Reset() {
+    filled_ = false;
+    map_.clear();
+    Destroy();
+    Setup();
+  }
+
+ private:
+  bool filled_ = false;
+  grpc_metadata_array arr_;
+  std::multimap<grpc::string_ref, grpc::string_ref> map_;
+
+  void Destroy() { grpc_metadata_array_destroy(&arr_); }
+
+  void Setup() { memset(&arr_, 0, sizeof(arr_)); }
+
+  void FillMap() {
+    if (filled_) return;
+    filled_ = true;
+    for (size_t i = 0; i < arr_.count; i++) {
+      // TODO(yangg) handle duplicates?
+      map_.insert(std::pair<grpc::string_ref, grpc::string_ref>(
+          StringRefFromSlice(&arr_.metadata[i].key),
+          StringRefFromSlice(&arr_.metadata[i].value)));
+    }
+  }
+};
+}  // namespace internal
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_METADATA_MAP_H

Pods/gRPC-C++/include/grpcpp/impl/method_handler_impl.h

@@ -0,0 +1,24 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_METHOD_HANDLER_IMPL_H
+#define GRPCPP_IMPL_METHOD_HANDLER_IMPL_H
+
+#include <grpcpp/support/method_handler.h>
+
+#endif  // GRPCPP_IMPL_METHOD_HANDLER_IMPL_H

Pods/gRPC-C++/include/grpcpp/impl/proto_utils.h

@@ -0,0 +1,117 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_PROTO_UTILS_H
+#define GRPCPP_IMPL_PROTO_UTILS_H
+
+#include <type_traits>
+
+#include <grpc/byte_buffer_reader.h>
+#include <grpc/impl/grpc_types.h>
+#include <grpc/slice.h>
+#include <grpc/support/log.h>
+#include <grpcpp/impl/codegen/config_protobuf.h>
+#include <grpcpp/impl/serialization_traits.h>
+#include <grpcpp/support/byte_buffer.h>
+#include <grpcpp/support/proto_buffer_reader.h>
+#include <grpcpp/support/proto_buffer_writer.h>
+#include <grpcpp/support/slice.h>
+#include <grpcpp/support/status.h>
+
+/// This header provides serialization and deserialization between gRPC
+/// messages serialized using protobuf and the C++ objects they represent.
+
+namespace grpc {
+
+// ProtoBufferWriter must be a subclass of ::protobuf::io::ZeroCopyOutputStream.
+template <class ProtoBufferWriter, class T>
+Status GenericSerialize(const grpc::protobuf::MessageLite& msg, ByteBuffer* bb,
+                        bool* own_buffer) {
+  static_assert(std::is_base_of<protobuf::io::ZeroCopyOutputStream,
+                                ProtoBufferWriter>::value,
+                "ProtoBufferWriter must be a subclass of "
+                "::protobuf::io::ZeroCopyOutputStream");
+  *own_buffer = true;
+  int byte_size = static_cast<int>(msg.ByteSizeLong());
+  if (static_cast<size_t>(byte_size) <= GRPC_SLICE_INLINED_SIZE) {
+    Slice slice(byte_size);
+    // We serialize directly into the allocated slices memory
+    GPR_ASSERT(slice.end() == msg.SerializeWithCachedSizesToArray(
+                                  const_cast<uint8_t*>(slice.begin())));
+    ByteBuffer tmp(&slice, 1);
+    bb->Swap(&tmp);
+
+    return grpc::Status::OK;
+  }
+  ProtoBufferWriter writer(bb, kProtoBufferWriterMaxBufferLength, byte_size);
+  return msg.SerializeToZeroCopyStream(&writer)
+             ? grpc::Status::OK
+             : Status(StatusCode::INTERNAL, "Failed to serialize message");
+}
+
+// BufferReader must be a subclass of ::protobuf::io::ZeroCopyInputStream.
+template <class ProtoBufferReader, class T>
+Status GenericDeserialize(ByteBuffer* buffer,
+                          grpc::protobuf::MessageLite* msg) {
+  static_assert(std::is_base_of<protobuf::io::ZeroCopyInputStream,
+                                ProtoBufferReader>::value,
+                "ProtoBufferReader must be a subclass of "
+                "::protobuf::io::ZeroCopyInputStream");
+  if (buffer == nullptr) {
+    return Status(StatusCode::INTERNAL, "No payload");
+  }
+  Status result = grpc::Status::OK;
+  {
+    ProtoBufferReader reader(buffer);
+    if (!reader.status().ok()) {
+      return reader.status();
+    }
+    if (!msg->ParseFromZeroCopyStream(&reader)) {
+      result = Status(StatusCode::INTERNAL, msg->InitializationErrorString());
+    }
+  }
+  buffer->Clear();
+  return result;
+}
+
+// this is needed so the following class does not conflict with protobuf
+// serializers that utilize internal-only tools.
+#ifdef GRPC_OPEN_SOURCE_PROTO
+// This class provides a protobuf serializer. It translates between protobuf
+// objects and grpc_byte_buffers. More information about SerializationTraits can
+// be found in include/grpcpp/impl/codegen/serialization_traits.h.
+template <class T>
+class SerializationTraits<
+    T, typename std::enable_if<
+           std::is_base_of<grpc::protobuf::MessageLite, T>::value>::type> {
+ public:
+  static Status Serialize(const grpc::protobuf::MessageLite& msg,
+                          ByteBuffer* bb, bool* own_buffer) {
+    return GenericSerialize<ProtoBufferWriter, T>(msg, bb, own_buffer);
+  }
+
+  static Status Deserialize(ByteBuffer* buffer,
+                            grpc::protobuf::MessageLite* msg) {
+    return GenericDeserialize<ProtoBufferReader, T>(buffer, msg);
+  }
+};
+#endif
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_PROTO_UTILS_H

Pods/gRPC-C++/include/grpcpp/impl/rpc_method.h

@@ -0,0 +1,80 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_RPC_METHOD_H
+#define GRPCPP_IMPL_RPC_METHOD_H
+
+#include <memory>
+
+#include <grpcpp/impl/codegen/channel_interface.h>
+
+namespace grpc {
+namespace internal {
+/// Descriptor of an RPC method
+class RpcMethod {
+ public:
+  enum RpcType {
+    NORMAL_RPC = 0,
+    CLIENT_STREAMING,  // request streaming
+    SERVER_STREAMING,  // response streaming
+    BIDI_STREAMING
+  };
+
+  RpcMethod(const char* name, RpcType type)
+      : name_(name),
+        suffix_for_stats_(nullptr),
+        method_type_(type),
+        channel_tag_(nullptr) {}
+
+  RpcMethod(const char* name, const char* suffix_for_stats, RpcType type)
+      : name_(name),
+        suffix_for_stats_(suffix_for_stats),
+        method_type_(type),
+        channel_tag_(nullptr) {}
+
+  RpcMethod(const char* name, RpcType type,
+            const std::shared_ptr<ChannelInterface>& channel)
+      : name_(name),
+        suffix_for_stats_(nullptr),
+        method_type_(type),
+        channel_tag_(channel->RegisterMethod(name)) {}
+
+  RpcMethod(const char* name, const char* suffix_for_stats, RpcType type,
+            const std::shared_ptr<ChannelInterface>& channel)
+      : name_(name),
+        suffix_for_stats_(suffix_for_stats),
+        method_type_(type),
+        channel_tag_(channel->RegisterMethod(name)) {}
+
+  const char* name() const { return name_; }
+  const char* suffix_for_stats() const { return suffix_for_stats_; }
+  RpcType method_type() const { return method_type_; }
+  void SetMethodType(RpcType type) { method_type_ = type; }
+  void* channel_tag() const { return channel_tag_; }
+
+ private:
+  const char* const name_;
+  const char* const suffix_for_stats_;
+  RpcType method_type_;
+  void* const channel_tag_;
+};
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_RPC_METHOD_H

Pods/gRPC-C++/include/grpcpp/impl/rpc_service_method.h

@@ -0,0 +1,153 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_RPC_SERVICE_METHOD_H
+#define GRPCPP_IMPL_RPC_SERVICE_METHOD_H
+
+#include <climits>
+#include <functional>
+#include <map>
+#include <memory>
+#include <vector>
+
+#include <grpc/support/log.h>
+#include <grpcpp/impl/rpc_method.h>
+#include <grpcpp/support/byte_buffer.h>
+#include <grpcpp/support/config.h>
+#include <grpcpp/support/status.h>
+
+namespace grpc {
+class ServerContextBase;
+namespace internal {
+/// Base class for running an RPC handler.
+class MethodHandler {
+ public:
+  virtual ~MethodHandler() {}
+  struct HandlerParameter {
+    /// Constructor for HandlerParameter
+    ///
+    /// \param c : the gRPC Call structure for this server call
+    /// \param context : the ServerContext structure for this server call
+    /// \param req : the request payload, if appropriate for this RPC
+    /// \param req_status : the request status after any interceptors have run
+    /// \param handler_data: internal data for the handler.
+    /// \param requester : used only by the callback API. It is a function
+    ///        called by the RPC Controller to request another RPC (and also
+    ///        to set up the state required to make that request possible)
+    HandlerParameter(Call* c, grpc::ServerContextBase* context, void* req,
+                     Status req_status, void* handler_data,
+                     std::function<void()> requester)
+        : call(c),
+          server_context(context),
+          request(req),
+          status(req_status),
+          internal_data(handler_data),
+          call_requester(std::move(requester)) {}
+    ~HandlerParameter() {}
+    Call* const call;
+    grpc::ServerContextBase* const server_context;
+    void* const request;
+    const Status status;
+    void* const internal_data;
+    const std::function<void()> call_requester;
+  };
+  virtual void RunHandler(const HandlerParameter& param) = 0;
+
+  // Returns a pointer to the deserialized request. \a status reflects the
+  // result of deserialization. This pointer and the status should be filled in
+  // a HandlerParameter and passed to RunHandler. It is illegal to access the
+  // pointer after calling RunHandler. Ownership of the deserialized request is
+  // retained by the handler. Returns nullptr if deserialization failed.
+  virtual void* Deserialize(grpc_call* /*call*/, grpc_byte_buffer* req,
+                            Status* /*status*/, void** /*handler_data*/) {
+    GPR_ASSERT(req == nullptr);
+    return nullptr;
+  }
+};
+
+/// Server side rpc method class
+class RpcServiceMethod : public RpcMethod {
+ public:
+  /// Takes ownership of the handler
+  RpcServiceMethod(const char* name, RpcMethod::RpcType type,
+                   MethodHandler* handler)
+      : RpcMethod(name, type),
+        server_tag_(nullptr),
+        api_type_(ApiType::SYNC),
+        handler_(handler) {}
+
+  enum class ApiType {
+    SYNC,
+    ASYNC,
+    RAW,
+    CALL_BACK,  // not CALLBACK because that is reserved in Windows
+    RAW_CALL_BACK,
+  };
+
+  void set_server_tag(void* tag) { server_tag_ = tag; }
+  void* server_tag() const { return server_tag_; }
+  /// if MethodHandler is nullptr, then this is an async method
+  MethodHandler* handler() const { return handler_.get(); }
+  ApiType api_type() const { return api_type_; }
+  void SetHandler(MethodHandler* handler) { handler_.reset(handler); }
+  void SetServerApiType(RpcServiceMethod::ApiType type) {
+    if ((api_type_ == ApiType::SYNC) &&
+        (type == ApiType::ASYNC || type == ApiType::RAW)) {
+      // this marks this method as async
+      handler_.reset();
+    } else if (api_type_ != ApiType::SYNC) {
+      // this is not an error condition, as it allows users to declare a server
+      // like WithRawMethod_foo<AsyncService>. However since it
+      // overwrites behavior, it should be logged.
+      gpr_log(
+          GPR_INFO,
+          "You are marking method %s as '%s', even though it was "
+          "previously marked '%s'. This behavior will overwrite the original "
+          "behavior. If you expected this then ignore this message.",
+          name(), TypeToString(api_type_), TypeToString(type));
+    }
+    api_type_ = type;
+  }
+
+ private:
+  void* server_tag_;
+  ApiType api_type_;
+  std::unique_ptr<MethodHandler> handler_;
+
+  const char* TypeToString(RpcServiceMethod::ApiType type) {
+    switch (type) {
+      case ApiType::SYNC:
+        return "sync";
+      case ApiType::ASYNC:
+        return "async";
+      case ApiType::RAW:
+        return "raw";
+      case ApiType::CALL_BACK:
+        return "callback";
+      case ApiType::RAW_CALL_BACK:
+        return "raw_callback";
+      default:
+        GPR_UNREACHABLE_CODE(return "unknown");
+    }
+  }
+};
+}  // namespace internal
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_RPC_SERVICE_METHOD_H

Pods/gRPC-C++/include/grpcpp/impl/serialization_traits.h

@@ -0,0 +1,62 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_SERIALIZATION_TRAITS_H
+#define GRPCPP_IMPL_SERIALIZATION_TRAITS_H
+
+namespace grpc {
+
+/// Defines how to serialize and deserialize some type.
+///
+/// Used for hooking different message serialization API's into GRPC.
+/// Each SerializationTraits<Message> implementation must provide the
+/// following functions:
+/// 1.  static Status Serialize(const Message& msg,
+///                             ByteBuffer* buffer,
+///                             bool* own_buffer);
+///     OR
+///     static Status Serialize(const Message& msg,
+///                             grpc_byte_buffer** buffer,
+///                             bool* own_buffer);
+///     The former is preferred; the latter is deprecated
+///
+/// 2.  static Status Deserialize(ByteBuffer* buffer,
+///                               Message* msg);
+///     OR
+///     static Status Deserialize(grpc_byte_buffer* buffer,
+///                               Message* msg);
+///     The former is preferred; the latter is deprecated
+///
+/// Serialize is required to convert message to a ByteBuffer, and
+/// return that byte buffer through *buffer. *own_buffer should
+/// be set to true if the caller owns said byte buffer, or false if
+/// ownership is retained elsewhere.
+///
+/// Deserialize is required to convert buffer into the message stored at
+/// msg. max_receive_message_size is passed in as a bound on the maximum
+/// number of message bytes Deserialize should accept.
+///
+/// Both functions return a Status, allowing them to explain what went
+/// wrong if required.
+template <class Message,
+          class UnusedButHereForPartialTemplateSpecialization = void>
+class SerializationTraits;
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SERIALIZATION_TRAITS_H

Pods/gRPC-C++/include/grpcpp/impl/server_builder_option.h

@@ -0,0 +1,43 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_SERVER_BUILDER_OPTION_H
+#define GRPCPP_IMPL_SERVER_BUILDER_OPTION_H
+
+#include <map>
+#include <memory>
+
+#include <grpcpp/impl/server_builder_plugin.h>
+#include <grpcpp/support/channel_arguments.h>
+
+namespace grpc {
+
+/// Interface to pass an option to a \a ServerBuilder.
+class ServerBuilderOption {
+ public:
+  virtual ~ServerBuilderOption() {}
+  /// Alter the \a ChannelArguments used to create the gRPC server.
+  virtual void UpdateArguments(grpc::ChannelArguments* args) = 0;
+  /// Alter the ServerBuilderPlugin map that will be added into ServerBuilder.
+  virtual void UpdatePlugins(
+      std::vector<std::unique_ptr<grpc::ServerBuilderPlugin>>* plugins) = 0;
+};
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SERVER_BUILDER_OPTION_H

Pods/gRPC-C++/include/grpcpp/impl/server_builder_plugin.h

@@ -0,0 +1,66 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_SERVER_BUILDER_PLUGIN_H
+#define GRPCPP_IMPL_SERVER_BUILDER_PLUGIN_H
+
+#include <memory>
+
+#include <grpcpp/support/channel_arguments.h>
+#include <grpcpp/support/config.h>
+
+namespace grpc {
+
+class ServerBuilder;
+class ServerInitializer;
+
+/// This interface is meant for internal usage only. Implementations of this
+/// interface should add themselves to a \a ServerBuilder instance through the
+/// \a InternalAddPluginFactory method.
+class ServerBuilderPlugin {
+ public:
+  virtual ~ServerBuilderPlugin() {}
+  virtual std::string name() = 0;
+
+  /// UpdateServerBuilder will be called at an early stage in
+  /// ServerBuilder::BuildAndStart(), right after the ServerBuilderOptions have
+  /// done their updates.
+  virtual void UpdateServerBuilder(ServerBuilder* /*builder*/) {}
+
+  /// InitServer will be called in ServerBuilder::BuildAndStart(), after the
+  /// Server instance is created.
+  virtual void InitServer(ServerInitializer* si) = 0;
+
+  /// Finish will be called at the end of ServerBuilder::BuildAndStart().
+  virtual void Finish(ServerInitializer* si) = 0;
+
+  /// ChangeArguments is an interface that can be used in
+  /// ServerBuilderOption::UpdatePlugins
+  virtual void ChangeArguments(const std::string& name, void* value) = 0;
+
+  /// UpdateChannelArguments will be called in ServerBuilder::BuildAndStart(),
+  /// before the Server instance is created.
+  virtual void UpdateChannelArguments(ChannelArguments* /*args*/) {}
+
+  virtual bool has_sync_methods() const { return false; }
+  virtual bool has_async_methods() const { return false; }
+};
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SERVER_BUILDER_PLUGIN_H

Pods/gRPC-C++/include/grpcpp/impl/server_callback_handlers.h

@@ -0,0 +1,888 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPCPP_IMPL_SERVER_CALLBACK_HANDLERS_H
+#define GRPCPP_IMPL_SERVER_CALLBACK_HANDLERS_H
+
+#include <grpc/grpc.h>
+#include <grpc/support/log.h>
+#include <grpcpp/impl/rpc_service_method.h>
+#include <grpcpp/server_context.h>
+#include <grpcpp/support/message_allocator.h>
+#include <grpcpp/support/server_callback.h>
+#include <grpcpp/support/status.h>
+
+namespace grpc {
+namespace internal {
+
+template <class RequestType, class ResponseType>
+class CallbackUnaryHandler : public grpc::internal::MethodHandler {
+ public:
+  explicit CallbackUnaryHandler(
+      std::function<ServerUnaryReactor*(grpc::CallbackServerContext*,
+                                        const RequestType*, ResponseType*)>
+          get_reactor)
+      : get_reactor_(std::move(get_reactor)) {}
+
+  void SetMessageAllocator(
+      MessageAllocator<RequestType, ResponseType>* allocator) {
+    allocator_ = allocator;
+  }
+
+  void RunHandler(const HandlerParameter& param) final {
+    // Arena allocate a controller structure (that includes request/response)
+    grpc_call_ref(param.call->call());
+    auto* allocator_state =
+        static_cast<MessageHolder<RequestType, ResponseType>*>(
+            param.internal_data);
+
+    auto* call = new (grpc_call_arena_alloc(param.call->call(),
+                                            sizeof(ServerCallbackUnaryImpl)))
+        ServerCallbackUnaryImpl(
+            static_cast<grpc::CallbackServerContext*>(param.server_context),
+            param.call, allocator_state, param.call_requester);
+    param.server_context->BeginCompletionOp(
+        param.call, [call](bool) { call->MaybeDone(); }, call);
+
+    ServerUnaryReactor* reactor = nullptr;
+    if (param.status.ok()) {
+      reactor = grpc::internal::CatchingReactorGetter<ServerUnaryReactor>(
+          get_reactor_,
+          static_cast<grpc::CallbackServerContext*>(param.server_context),
+          call->request(), call->response());
+    }
+
+    if (reactor == nullptr) {
+      // if deserialization or reactor creator failed, we need to fail the call
+      reactor = new (grpc_call_arena_alloc(param.call->call(),
+                                           sizeof(UnimplementedUnaryReactor)))
+          UnimplementedUnaryReactor(
+              grpc::Status(grpc::StatusCode::UNIMPLEMENTED, ""));
+    }
+
+    /// Invoke SetupReactor as the last part of the handler
+    call->SetupReactor(reactor);
+  }
+
+  void* Deserialize(grpc_call* call, grpc_byte_buffer* req,
+                    grpc::Status* status, void** handler_data) final {
+    grpc::ByteBuffer buf;
+    buf.set_buffer(req);
+    RequestType* request = nullptr;
+    MessageHolder<RequestType, ResponseType>* allocator_state;
+    if (allocator_ != nullptr) {
+      allocator_state = allocator_->AllocateMessages();
+    } else {
+      allocator_state = new (grpc_call_arena_alloc(
+          call, sizeof(DefaultMessageHolder<RequestType, ResponseType>)))
+          DefaultMessageHolder<RequestType, ResponseType>();
+    }
+    *handler_data = allocator_state;
+    request = allocator_state->request();
+    *status =
+        grpc::SerializationTraits<RequestType>::Deserialize(&buf, request);
+    buf.Release();
+    if (status->ok()) {
+      return request;
+    }
+    return nullptr;
+  }
+
+ private:
+  std::function<ServerUnaryReactor*(grpc::CallbackServerContext*,
+                                    const RequestType*, ResponseType*)>
+      get_reactor_;
+  MessageAllocator<RequestType, ResponseType>* allocator_ = nullptr;
+
+  class ServerCallbackUnaryImpl : public ServerCallbackUnary {
+   public:
+    void Finish(grpc::Status s) override {
+      // A callback that only contains a call to MaybeDone can be run as an
+      // inline callback regardless of whether or not OnDone is inlineable
+      // because if the actual OnDone callback needs to be scheduled, MaybeDone
+      // is responsible for dispatching to an executor thread if needed. Thus,
+      // when setting up the finish_tag_, we can set its own callback to
+      // inlineable.
+      finish_tag_.Set(
+          call_.call(),
+          [this](bool) {
+            this->MaybeDone(
+                reactor_.load(std::memory_order_relaxed)->InternalInlineable());
+          },
+          &finish_ops_, /*can_inline=*/true);
+      finish_ops_.set_core_cq_tag(&finish_tag_);
+
+      if (!ctx_->sent_initial_metadata_) {
+        finish_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                        ctx_->initial_metadata_flags());
+        if (ctx_->compression_level_set()) {
+          finish_ops_.set_compression_level(ctx_->compression_level());
+        }
+        ctx_->sent_initial_metadata_ = true;
+      }
+      // The response is dropped if the status is not OK.
+      if (s.ok()) {
+        finish_ops_.ServerSendStatus(&ctx_->trailing_metadata_,
+                                     finish_ops_.SendMessagePtr(response()));
+      } else {
+        finish_ops_.ServerSendStatus(&ctx_->trailing_metadata_, s);
+      }
+      finish_ops_.set_core_cq_tag(&finish_tag_);
+      call_.PerformOps(&finish_ops_);
+    }
+
+    void SendInitialMetadata() override {
+      GPR_ASSERT(!ctx_->sent_initial_metadata_);
+      this->Ref();
+      // The callback for this function should not be marked inline because it
+      // is directly invoking a user-controlled reaction
+      // (OnSendInitialMetadataDone). Thus it must be dispatched to an executor
+      // thread. However, any OnDone needed after that can be inlined because it
+      // is already running on an executor thread.
+      meta_tag_.Set(
+          call_.call(),
+          [this](bool ok) {
+            ServerUnaryReactor* reactor =
+                reactor_.load(std::memory_order_relaxed);
+            reactor->OnSendInitialMetadataDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &meta_ops_, /*can_inline=*/false);
+      meta_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                    ctx_->initial_metadata_flags());
+      if (ctx_->compression_level_set()) {
+        meta_ops_.set_compression_level(ctx_->compression_level());
+      }
+      ctx_->sent_initial_metadata_ = true;
+      meta_ops_.set_core_cq_tag(&meta_tag_);
+      call_.PerformOps(&meta_ops_);
+    }
+
+   private:
+    friend class CallbackUnaryHandler<RequestType, ResponseType>;
+
+    ServerCallbackUnaryImpl(
+        grpc::CallbackServerContext* ctx, grpc::internal::Call* call,
+        MessageHolder<RequestType, ResponseType>* allocator_state,
+        std::function<void()> call_requester)
+        : ctx_(ctx),
+          call_(*call),
+          allocator_state_(allocator_state),
+          call_requester_(std::move(call_requester)) {
+      ctx_->set_message_allocator_state(allocator_state);
+    }
+
+    /// SetupReactor binds the reactor (which also releases any queued
+    /// operations), maybe calls OnCancel if possible/needed, and maybe marks
+    /// the completion of the RPC. This should be the last component of the
+    /// handler.
+    void SetupReactor(ServerUnaryReactor* reactor) {
+      reactor_.store(reactor, std::memory_order_relaxed);
+      this->BindReactor(reactor);
+      this->MaybeCallOnCancel(reactor);
+      this->MaybeDone(reactor->InternalInlineable());
+    }
+
+    const RequestType* request() { return allocator_state_->request(); }
+    ResponseType* response() { return allocator_state_->response(); }
+
+    void CallOnDone() override {
+      reactor_.load(std::memory_order_relaxed)->OnDone();
+      grpc_call* call = call_.call();
+      auto call_requester = std::move(call_requester_);
+      allocator_state_->Release();
+      if (ctx_->context_allocator() != nullptr) {
+        ctx_->context_allocator()->Release(ctx_);
+      }
+      this->~ServerCallbackUnaryImpl();  // explicitly call destructor
+      grpc_call_unref(call);
+      call_requester();
+    }
+
+    ServerReactor* reactor() override {
+      return reactor_.load(std::memory_order_relaxed);
+    }
+
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata>
+        meta_ops_;
+    grpc::internal::CallbackWithSuccessTag meta_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata,
+                              grpc::internal::CallOpSendMessage,
+                              grpc::internal::CallOpServerSendStatus>
+        finish_ops_;
+    grpc::internal::CallbackWithSuccessTag finish_tag_;
+
+    grpc::CallbackServerContext* const ctx_;
+    grpc::internal::Call call_;
+    MessageHolder<RequestType, ResponseType>* const allocator_state_;
+    std::function<void()> call_requester_;
+    // reactor_ can always be loaded/stored with relaxed memory ordering because
+    // its value is only set once, independently of other data in the object,
+    // and the loads that use it will always actually come provably later even
+    // though they are from different threads since they are triggered by
+    // actions initiated only by the setting up of the reactor_ variable. In
+    // a sense, it's a delayed "const": it gets its value from the SetupReactor
+    // method (not the constructor, so it's not a true const), but it doesn't
+    // change after that and it only gets used by actions caused, directly or
+    // indirectly, by that setup. This comment also applies to the reactor_
+    // variables of the other streaming objects in this file.
+    std::atomic<ServerUnaryReactor*> reactor_;
+    // callbacks_outstanding_ follows a refcount pattern
+    std::atomic<intptr_t> callbacks_outstanding_{
+        3};  // reserve for start, Finish, and CompletionOp
+  };
+};
+
+template <class RequestType, class ResponseType>
+class CallbackClientStreamingHandler : public grpc::internal::MethodHandler {
+ public:
+  explicit CallbackClientStreamingHandler(
+      std::function<ServerReadReactor<RequestType>*(
+          grpc::CallbackServerContext*, ResponseType*)>
+          get_reactor)
+      : get_reactor_(std::move(get_reactor)) {}
+  void RunHandler(const HandlerParameter& param) final {
+    // Arena allocate a reader structure (that includes response)
+    grpc_call_ref(param.call->call());
+
+    auto* reader = new (grpc_call_arena_alloc(param.call->call(),
+                                              sizeof(ServerCallbackReaderImpl)))
+        ServerCallbackReaderImpl(
+            static_cast<grpc::CallbackServerContext*>(param.server_context),
+            param.call, param.call_requester);
+    // Inlineable OnDone can be false in the CompletionOp callback because there
+    // is no read reactor that has an inlineable OnDone; this only applies to
+    // the DefaultReactor (which is unary).
+    param.server_context->BeginCompletionOp(
+        param.call,
+        [reader](bool) { reader->MaybeDone(/*inlineable_ondone=*/false); },
+        reader);
+
+    ServerReadReactor<RequestType>* reactor = nullptr;
+    if (param.status.ok()) {
+      reactor =
+          grpc::internal::CatchingReactorGetter<ServerReadReactor<RequestType>>(
+              get_reactor_,
+              static_cast<grpc::CallbackServerContext*>(param.server_context),
+              reader->response());
+    }
+
+    if (reactor == nullptr) {
+      // if deserialization or reactor creator failed, we need to fail the call
+      reactor = new (grpc_call_arena_alloc(
+          param.call->call(), sizeof(UnimplementedReadReactor<RequestType>)))
+          UnimplementedReadReactor<RequestType>(
+              grpc::Status(grpc::StatusCode::UNIMPLEMENTED, ""));
+    }
+
+    reader->SetupReactor(reactor);
+  }
+
+ private:
+  std::function<ServerReadReactor<RequestType>*(grpc::CallbackServerContext*,
+                                                ResponseType*)>
+      get_reactor_;
+
+  class ServerCallbackReaderImpl : public ServerCallbackReader<RequestType> {
+   public:
+    void Finish(grpc::Status s) override {
+      // A finish tag with only MaybeDone can have its callback inlined
+      // regardless even if OnDone is not inlineable because this callback just
+      // checks a ref and then decides whether or not to dispatch OnDone.
+      finish_tag_.Set(
+          call_.call(),
+          [this](bool) {
+            // Inlineable OnDone can be false here because there is
+            // no read reactor that has an inlineable OnDone; this
+            // only applies to the DefaultReactor (which is unary).
+            this->MaybeDone(/*inlineable_ondone=*/false);
+          },
+          &finish_ops_, /*can_inline=*/true);
+      if (!ctx_->sent_initial_metadata_) {
+        finish_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                        ctx_->initial_metadata_flags());
+        if (ctx_->compression_level_set()) {
+          finish_ops_.set_compression_level(ctx_->compression_level());
+        }
+        ctx_->sent_initial_metadata_ = true;
+      }
+      // The response is dropped if the status is not OK.
+      if (s.ok()) {
+        finish_ops_.ServerSendStatus(&ctx_->trailing_metadata_,
+                                     finish_ops_.SendMessagePtr(&resp_));
+      } else {
+        finish_ops_.ServerSendStatus(&ctx_->trailing_metadata_, s);
+      }
+      finish_ops_.set_core_cq_tag(&finish_tag_);
+      call_.PerformOps(&finish_ops_);
+    }
+
+    void SendInitialMetadata() override {
+      GPR_ASSERT(!ctx_->sent_initial_metadata_);
+      this->Ref();
+      // The callback for this function should not be inlined because it invokes
+      // a user-controlled reaction, but any resulting OnDone can be inlined in
+      // the executor to which this callback is dispatched.
+      meta_tag_.Set(
+          call_.call(),
+          [this](bool ok) {
+            ServerReadReactor<RequestType>* reactor =
+                reactor_.load(std::memory_order_relaxed);
+            reactor->OnSendInitialMetadataDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &meta_ops_, /*can_inline=*/false);
+      meta_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                    ctx_->initial_metadata_flags());
+      if (ctx_->compression_level_set()) {
+        meta_ops_.set_compression_level(ctx_->compression_level());
+      }
+      ctx_->sent_initial_metadata_ = true;
+      meta_ops_.set_core_cq_tag(&meta_tag_);
+      call_.PerformOps(&meta_ops_);
+    }
+
+    void Read(RequestType* req) override {
+      this->Ref();
+      read_ops_.RecvMessage(req);
+      call_.PerformOps(&read_ops_);
+    }
+
+   private:
+    friend class CallbackClientStreamingHandler<RequestType, ResponseType>;
+
+    ServerCallbackReaderImpl(grpc::CallbackServerContext* ctx,
+                             grpc::internal::Call* call,
+                             std::function<void()> call_requester)
+        : ctx_(ctx), call_(*call), call_requester_(std::move(call_requester)) {}
+
+    void SetupReactor(ServerReadReactor<RequestType>* reactor) {
+      reactor_.store(reactor, std::memory_order_relaxed);
+      // The callback for this function should not be inlined because it invokes
+      // a user-controlled reaction, but any resulting OnDone can be inlined in
+      // the executor to which this callback is dispatched.
+      read_tag_.Set(
+          call_.call(),
+          [this, reactor](bool ok) {
+            if (GPR_UNLIKELY(!ok)) {
+              ctx_->MaybeMarkCancelledOnRead();
+            }
+            reactor->OnReadDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &read_ops_, /*can_inline=*/false);
+      read_ops_.set_core_cq_tag(&read_tag_);
+      this->BindReactor(reactor);
+      this->MaybeCallOnCancel(reactor);
+      // Inlineable OnDone can be false here because there is no read
+      // reactor that has an inlineable OnDone; this only applies to the
+      // DefaultReactor (which is unary).
+      this->MaybeDone(/*inlineable_ondone=*/false);
+    }
+
+    ~ServerCallbackReaderImpl() {}
+
+    ResponseType* response() { return &resp_; }
+
+    void CallOnDone() override {
+      reactor_.load(std::memory_order_relaxed)->OnDone();
+      grpc_call* call = call_.call();
+      auto call_requester = std::move(call_requester_);
+      if (ctx_->context_allocator() != nullptr) {
+        ctx_->context_allocator()->Release(ctx_);
+      }
+      this->~ServerCallbackReaderImpl();  // explicitly call destructor
+      grpc_call_unref(call);
+      call_requester();
+    }
+
+    ServerReactor* reactor() override {
+      return reactor_.load(std::memory_order_relaxed);
+    }
+
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata>
+        meta_ops_;
+    grpc::internal::CallbackWithSuccessTag meta_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata,
+                              grpc::internal::CallOpSendMessage,
+                              grpc::internal::CallOpServerSendStatus>
+        finish_ops_;
+    grpc::internal::CallbackWithSuccessTag finish_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpRecvMessage<RequestType>>
+        read_ops_;
+    grpc::internal::CallbackWithSuccessTag read_tag_;
+
+    grpc::CallbackServerContext* const ctx_;
+    grpc::internal::Call call_;
+    ResponseType resp_;
+    std::function<void()> call_requester_;
+    // The memory ordering of reactor_ follows ServerCallbackUnaryImpl.
+    std::atomic<ServerReadReactor<RequestType>*> reactor_;
+    // callbacks_outstanding_ follows a refcount pattern
+    std::atomic<intptr_t> callbacks_outstanding_{
+        3};  // reserve for OnStarted, Finish, and CompletionOp
+  };
+};
+
+template <class RequestType, class ResponseType>
+class CallbackServerStreamingHandler : public grpc::internal::MethodHandler {
+ public:
+  explicit CallbackServerStreamingHandler(
+      std::function<ServerWriteReactor<ResponseType>*(
+          grpc::CallbackServerContext*, const RequestType*)>
+          get_reactor)
+      : get_reactor_(std::move(get_reactor)) {}
+  void RunHandler(const HandlerParameter& param) final {
+    // Arena allocate a writer structure
+    grpc_call_ref(param.call->call());
+
+    auto* writer = new (grpc_call_arena_alloc(param.call->call(),
+                                              sizeof(ServerCallbackWriterImpl)))
+        ServerCallbackWriterImpl(
+            static_cast<grpc::CallbackServerContext*>(param.server_context),
+            param.call, static_cast<RequestType*>(param.request),
+            param.call_requester);
+    // Inlineable OnDone can be false in the CompletionOp callback because there
+    // is no write reactor that has an inlineable OnDone; this only applies to
+    // the DefaultReactor (which is unary).
+    param.server_context->BeginCompletionOp(
+        param.call,
+        [writer](bool) { writer->MaybeDone(/*inlineable_ondone=*/false); },
+        writer);
+
+    ServerWriteReactor<ResponseType>* reactor = nullptr;
+    if (param.status.ok()) {
+      reactor = grpc::internal::CatchingReactorGetter<
+          ServerWriteReactor<ResponseType>>(
+          get_reactor_,
+          static_cast<grpc::CallbackServerContext*>(param.server_context),
+          writer->request());
+    }
+    if (reactor == nullptr) {
+      // if deserialization or reactor creator failed, we need to fail the call
+      reactor = new (grpc_call_arena_alloc(
+          param.call->call(), sizeof(UnimplementedWriteReactor<ResponseType>)))
+          UnimplementedWriteReactor<ResponseType>(
+              grpc::Status(grpc::StatusCode::UNIMPLEMENTED, ""));
+    }
+
+    writer->SetupReactor(reactor);
+  }
+
+  void* Deserialize(grpc_call* call, grpc_byte_buffer* req,
+                    grpc::Status* status, void** /*handler_data*/) final {
+    grpc::ByteBuffer buf;
+    buf.set_buffer(req);
+    auto* request =
+        new (grpc_call_arena_alloc(call, sizeof(RequestType))) RequestType();
+    *status =
+        grpc::SerializationTraits<RequestType>::Deserialize(&buf, request);
+    buf.Release();
+    if (status->ok()) {
+      return request;
+    }
+    request->~RequestType();
+    return nullptr;
+  }
+
+ private:
+  std::function<ServerWriteReactor<ResponseType>*(grpc::CallbackServerContext*,
+                                                  const RequestType*)>
+      get_reactor_;
+
+  class ServerCallbackWriterImpl : public ServerCallbackWriter<ResponseType> {
+   public:
+    void Finish(grpc::Status s) override {
+      // A finish tag with only MaybeDone can have its callback inlined
+      // regardless even if OnDone is not inlineable because this callback just
+      // checks a ref and then decides whether or not to dispatch OnDone.
+      finish_tag_.Set(
+          call_.call(),
+          [this](bool) {
+            // Inlineable OnDone can be false here because there is
+            // no write reactor that has an inlineable OnDone; this
+            // only applies to the DefaultReactor (which is unary).
+            this->MaybeDone(/*inlineable_ondone=*/false);
+          },
+          &finish_ops_, /*can_inline=*/true);
+      finish_ops_.set_core_cq_tag(&finish_tag_);
+
+      if (!ctx_->sent_initial_metadata_) {
+        finish_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                        ctx_->initial_metadata_flags());
+        if (ctx_->compression_level_set()) {
+          finish_ops_.set_compression_level(ctx_->compression_level());
+        }
+        ctx_->sent_initial_metadata_ = true;
+      }
+      finish_ops_.ServerSendStatus(&ctx_->trailing_metadata_, s);
+      call_.PerformOps(&finish_ops_);
+    }
+
+    void SendInitialMetadata() override {
+      GPR_ASSERT(!ctx_->sent_initial_metadata_);
+      this->Ref();
+      // The callback for this function should not be inlined because it invokes
+      // a user-controlled reaction, but any resulting OnDone can be inlined in
+      // the executor to which this callback is dispatched.
+      meta_tag_.Set(
+          call_.call(),
+          [this](bool ok) {
+            ServerWriteReactor<ResponseType>* reactor =
+                reactor_.load(std::memory_order_relaxed);
+            reactor->OnSendInitialMetadataDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &meta_ops_, /*can_inline=*/false);
+      meta_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                    ctx_->initial_metadata_flags());
+      if (ctx_->compression_level_set()) {
+        meta_ops_.set_compression_level(ctx_->compression_level());
+      }
+      ctx_->sent_initial_metadata_ = true;
+      meta_ops_.set_core_cq_tag(&meta_tag_);
+      call_.PerformOps(&meta_ops_);
+    }
+
+    void Write(const ResponseType* resp, grpc::WriteOptions options) override {
+      this->Ref();
+      if (options.is_last_message()) {
+        options.set_buffer_hint();
+      }
+      if (!ctx_->sent_initial_metadata_) {
+        write_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                       ctx_->initial_metadata_flags());
+        if (ctx_->compression_level_set()) {
+          write_ops_.set_compression_level(ctx_->compression_level());
+        }
+        ctx_->sent_initial_metadata_ = true;
+      }
+      // TODO(vjpai): don't assert
+      GPR_ASSERT(write_ops_.SendMessagePtr(resp, options).ok());
+      call_.PerformOps(&write_ops_);
+    }
+
+    void WriteAndFinish(const ResponseType* resp, grpc::WriteOptions options,
+                        grpc::Status s) override {
+      // This combines the write into the finish callback
+      // TODO(vjpai): don't assert
+      GPR_ASSERT(finish_ops_.SendMessagePtr(resp, options).ok());
+      Finish(std::move(s));
+    }
+
+   private:
+    friend class CallbackServerStreamingHandler<RequestType, ResponseType>;
+
+    ServerCallbackWriterImpl(grpc::CallbackServerContext* ctx,
+                             grpc::internal::Call* call, const RequestType* req,
+                             std::function<void()> call_requester)
+        : ctx_(ctx),
+          call_(*call),
+          req_(req),
+          call_requester_(std::move(call_requester)) {}
+
+    void SetupReactor(ServerWriteReactor<ResponseType>* reactor) {
+      reactor_.store(reactor, std::memory_order_relaxed);
+      // The callback for this function should not be inlined because it invokes
+      // a user-controlled reaction, but any resulting OnDone can be inlined in
+      // the executor to which this callback is dispatched.
+      write_tag_.Set(
+          call_.call(),
+          [this, reactor](bool ok) {
+            reactor->OnWriteDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &write_ops_, /*can_inline=*/false);
+      write_ops_.set_core_cq_tag(&write_tag_);
+      this->BindReactor(reactor);
+      this->MaybeCallOnCancel(reactor);
+      // Inlineable OnDone can be false here because there is no write
+      // reactor that has an inlineable OnDone; this only applies to the
+      // DefaultReactor (which is unary).
+      this->MaybeDone(/*inlineable_ondone=*/false);
+    }
+    ~ServerCallbackWriterImpl() {
+      if (req_ != nullptr) {
+        req_->~RequestType();
+      }
+    }
+
+    const RequestType* request() { return req_; }
+
+    void CallOnDone() override {
+      reactor_.load(std::memory_order_relaxed)->OnDone();
+      grpc_call* call = call_.call();
+      auto call_requester = std::move(call_requester_);
+      if (ctx_->context_allocator() != nullptr) {
+        ctx_->context_allocator()->Release(ctx_);
+      }
+      this->~ServerCallbackWriterImpl();  // explicitly call destructor
+      grpc_call_unref(call);
+      call_requester();
+    }
+
+    ServerReactor* reactor() override {
+      return reactor_.load(std::memory_order_relaxed);
+    }
+
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata>
+        meta_ops_;
+    grpc::internal::CallbackWithSuccessTag meta_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata,
+                              grpc::internal::CallOpSendMessage,
+                              grpc::internal::CallOpServerSendStatus>
+        finish_ops_;
+    grpc::internal::CallbackWithSuccessTag finish_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata,
+                              grpc::internal::CallOpSendMessage>
+        write_ops_;
+    grpc::internal::CallbackWithSuccessTag write_tag_;
+
+    grpc::CallbackServerContext* const ctx_;
+    grpc::internal::Call call_;
+    const RequestType* req_;
+    std::function<void()> call_requester_;
+    // The memory ordering of reactor_ follows ServerCallbackUnaryImpl.
+    std::atomic<ServerWriteReactor<ResponseType>*> reactor_;
+    // callbacks_outstanding_ follows a refcount pattern
+    std::atomic<intptr_t> callbacks_outstanding_{
+        3};  // reserve for OnStarted, Finish, and CompletionOp
+  };
+};
+
+template <class RequestType, class ResponseType>
+class CallbackBidiHandler : public grpc::internal::MethodHandler {
+ public:
+  explicit CallbackBidiHandler(
+      std::function<ServerBidiReactor<RequestType, ResponseType>*(
+          grpc::CallbackServerContext*)>
+          get_reactor)
+      : get_reactor_(std::move(get_reactor)) {}
+  void RunHandler(const HandlerParameter& param) final {
+    grpc_call_ref(param.call->call());
+
+    auto* stream = new (grpc_call_arena_alloc(
+        param.call->call(), sizeof(ServerCallbackReaderWriterImpl)))
+        ServerCallbackReaderWriterImpl(
+            static_cast<grpc::CallbackServerContext*>(param.server_context),
+            param.call, param.call_requester);
+    // Inlineable OnDone can be false in the CompletionOp callback because there
+    // is no bidi reactor that has an inlineable OnDone; this only applies to
+    // the DefaultReactor (which is unary).
+    param.server_context->BeginCompletionOp(
+        param.call,
+        [stream](bool) { stream->MaybeDone(/*inlineable_ondone=*/false); },
+        stream);
+
+    ServerBidiReactor<RequestType, ResponseType>* reactor = nullptr;
+    if (param.status.ok()) {
+      reactor = grpc::internal::CatchingReactorGetter<
+          ServerBidiReactor<RequestType, ResponseType>>(
+          get_reactor_,
+          static_cast<grpc::CallbackServerContext*>(param.server_context));
+    }
+
+    if (reactor == nullptr) {
+      // if deserialization or reactor creator failed, we need to fail the call
+      reactor = new (grpc_call_arena_alloc(
+          param.call->call(),
+          sizeof(UnimplementedBidiReactor<RequestType, ResponseType>)))
+          UnimplementedBidiReactor<RequestType, ResponseType>(
+              grpc::Status(grpc::StatusCode::UNIMPLEMENTED, ""));
+    }
+
+    stream->SetupReactor(reactor);
+  }
+
+ private:
+  std::function<ServerBidiReactor<RequestType, ResponseType>*(
+      grpc::CallbackServerContext*)>
+      get_reactor_;
+
+  class ServerCallbackReaderWriterImpl
+      : public ServerCallbackReaderWriter<RequestType, ResponseType> {
+   public:
+    void Finish(grpc::Status s) override {
+      // A finish tag with only MaybeDone can have its callback inlined
+      // regardless even if OnDone is not inlineable because this callback just
+      // checks a ref and then decides whether or not to dispatch OnDone.
+      finish_tag_.Set(
+          call_.call(),
+          [this](bool) {
+            // Inlineable OnDone can be false here because there is
+            // no bidi reactor that has an inlineable OnDone; this
+            // only applies to the DefaultReactor (which is unary).
+            this->MaybeDone(/*inlineable_ondone=*/false);
+          },
+          &finish_ops_, /*can_inline=*/true);
+      finish_ops_.set_core_cq_tag(&finish_tag_);
+
+      if (!ctx_->sent_initial_metadata_) {
+        finish_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                        ctx_->initial_metadata_flags());
+        if (ctx_->compression_level_set()) {
+          finish_ops_.set_compression_level(ctx_->compression_level());
+        }
+        ctx_->sent_initial_metadata_ = true;
+      }
+      finish_ops_.ServerSendStatus(&ctx_->trailing_metadata_, s);
+      call_.PerformOps(&finish_ops_);
+    }
+
+    void SendInitialMetadata() override {
+      GPR_ASSERT(!ctx_->sent_initial_metadata_);
+      this->Ref();
+      // The callback for this function should not be inlined because it invokes
+      // a user-controlled reaction, but any resulting OnDone can be inlined in
+      // the executor to which this callback is dispatched.
+      meta_tag_.Set(
+          call_.call(),
+          [this](bool ok) {
+            ServerBidiReactor<RequestType, ResponseType>* reactor =
+                reactor_.load(std::memory_order_relaxed);
+            reactor->OnSendInitialMetadataDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &meta_ops_, /*can_inline=*/false);
+      meta_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                    ctx_->initial_metadata_flags());
+      if (ctx_->compression_level_set()) {
+        meta_ops_.set_compression_level(ctx_->compression_level());
+      }
+      ctx_->sent_initial_metadata_ = true;
+      meta_ops_.set_core_cq_tag(&meta_tag_);
+      call_.PerformOps(&meta_ops_);
+    }
+
+    void Write(const ResponseType* resp, grpc::WriteOptions options) override {
+      this->Ref();
+      if (options.is_last_message()) {
+        options.set_buffer_hint();
+      }
+      if (!ctx_->sent_initial_metadata_) {
+        write_ops_.SendInitialMetadata(&ctx_->initial_metadata_,
+                                       ctx_->initial_metadata_flags());
+        if (ctx_->compression_level_set()) {
+          write_ops_.set_compression_level(ctx_->compression_level());
+        }
+        ctx_->sent_initial_metadata_ = true;
+      }
+      // TODO(vjpai): don't assert
+      GPR_ASSERT(write_ops_.SendMessagePtr(resp, options).ok());
+      call_.PerformOps(&write_ops_);
+    }
+
+    void WriteAndFinish(const ResponseType* resp, grpc::WriteOptions options,
+                        grpc::Status s) override {
+      // TODO(vjpai): don't assert
+      GPR_ASSERT(finish_ops_.SendMessagePtr(resp, options).ok());
+      Finish(std::move(s));
+    }
+
+    void Read(RequestType* req) override {
+      this->Ref();
+      read_ops_.RecvMessage(req);
+      call_.PerformOps(&read_ops_);
+    }
+
+   private:
+    friend class CallbackBidiHandler<RequestType, ResponseType>;
+
+    ServerCallbackReaderWriterImpl(grpc::CallbackServerContext* ctx,
+                                   grpc::internal::Call* call,
+                                   std::function<void()> call_requester)
+        : ctx_(ctx), call_(*call), call_requester_(std::move(call_requester)) {}
+
+    void SetupReactor(ServerBidiReactor<RequestType, ResponseType>* reactor) {
+      reactor_.store(reactor, std::memory_order_relaxed);
+      // The callbacks for these functions should not be inlined because they
+      // invoke user-controlled reactions, but any resulting OnDones can be
+      // inlined in the executor to which a callback is dispatched.
+      write_tag_.Set(
+          call_.call(),
+          [this, reactor](bool ok) {
+            reactor->OnWriteDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &write_ops_, /*can_inline=*/false);
+      write_ops_.set_core_cq_tag(&write_tag_);
+      read_tag_.Set(
+          call_.call(),
+          [this, reactor](bool ok) {
+            if (GPR_UNLIKELY(!ok)) {
+              ctx_->MaybeMarkCancelledOnRead();
+            }
+            reactor->OnReadDone(ok);
+            this->MaybeDone(/*inlineable_ondone=*/true);
+          },
+          &read_ops_, /*can_inline=*/false);
+      read_ops_.set_core_cq_tag(&read_tag_);
+      this->BindReactor(reactor);
+      this->MaybeCallOnCancel(reactor);
+      // Inlineable OnDone can be false here because there is no bidi
+      // reactor that has an inlineable OnDone; this only applies to the
+      // DefaultReactor (which is unary).
+      this->MaybeDone(/*inlineable_ondone=*/false);
+    }
+
+    void CallOnDone() override {
+      reactor_.load(std::memory_order_relaxed)->OnDone();
+      grpc_call* call = call_.call();
+      auto call_requester = std::move(call_requester_);
+      if (ctx_->context_allocator() != nullptr) {
+        ctx_->context_allocator()->Release(ctx_);
+      }
+      this->~ServerCallbackReaderWriterImpl();  // explicitly call destructor
+      grpc_call_unref(call);
+      call_requester();
+    }
+
+    ServerReactor* reactor() override {
+      return reactor_.load(std::memory_order_relaxed);
+    }
+
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata>
+        meta_ops_;
+    grpc::internal::CallbackWithSuccessTag meta_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata,
+                              grpc::internal::CallOpSendMessage,
+                              grpc::internal::CallOpServerSendStatus>
+        finish_ops_;
+    grpc::internal::CallbackWithSuccessTag finish_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpSendInitialMetadata,
+                              grpc::internal::CallOpSendMessage>
+        write_ops_;
+    grpc::internal::CallbackWithSuccessTag write_tag_;
+    grpc::internal::CallOpSet<grpc::internal::CallOpRecvMessage<RequestType>>
+        read_ops_;
+    grpc::internal::CallbackWithSuccessTag read_tag_;
+
+    grpc::CallbackServerContext* const ctx_;
+    grpc::internal::Call call_;
+    std::function<void()> call_requester_;
+    // The memory ordering of reactor_ follows ServerCallbackUnaryImpl.
+    std::atomic<ServerBidiReactor<RequestType, ResponseType>*> reactor_;
+    // callbacks_outstanding_ follows a refcount pattern
+    std::atomic<intptr_t> callbacks_outstanding_{
+        3};  // reserve for OnStarted, Finish, and CompletionOp
+  };
+};
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SERVER_CALLBACK_HANDLERS_H

Pods/gRPC-C++/include/grpcpp/impl/server_initializer.h

@@ -0,0 +1,54 @@
+//
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_SERVER_INITIALIZER_H
+#define GRPCPP_IMPL_SERVER_INITIALIZER_H
+
+#include <memory>
+#include <vector>
+
+#include <grpcpp/server.h>
+
+namespace grpc {
+class Server;
+class Service;
+
+class ServerInitializer {
+ public:
+  explicit ServerInitializer(grpc::Server* server) : server_(server) {}
+
+  bool RegisterService(std::shared_ptr<grpc::Service> service) {
+    if (!server_->RegisterService(nullptr, service.get())) {
+      return false;
+    }
+    default_services_.push_back(service);
+    return true;
+  }
+
+  const std::vector<std::string>* GetServiceList() {
+    return &server_->services_;
+  }
+
+ private:
+  grpc::Server* server_;
+  std::vector<std::shared_ptr<grpc::Service> > default_services_;
+};
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SERVER_INITIALIZER_H

Pods/gRPC-C++/include/grpcpp/impl/service_type.h

@@ -0,0 +1,235 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_SERVICE_TYPE_H
+#define GRPCPP_IMPL_SERVICE_TYPE_H
+
+#include <grpc/support/log.h>
+#include <grpcpp/impl/rpc_service_method.h>
+#include <grpcpp/impl/serialization_traits.h>
+#include <grpcpp/server_interface.h>
+#include <grpcpp/support/config.h>
+#include <grpcpp/support/status.h>
+
+namespace grpc {
+
+class CompletionQueue;
+class ServerContext;
+class ServerInterface;
+
+namespace internal {
+class Call;
+class ServerAsyncStreamingInterface {
+ public:
+  virtual ~ServerAsyncStreamingInterface() {}
+
+  /// Request notification of the sending of initial metadata to the client.
+  /// Completion will be notified by \a tag on the associated completion
+  /// queue. This call is optional, but if it is used, it cannot be used
+  /// concurrently with or after the \a Finish method.
+  ///
+  /// \param[in] tag Tag identifying this request.
+  virtual void SendInitialMetadata(void* tag) = 0;
+
+ private:
+  friend class grpc::ServerInterface;
+  virtual void BindCall(Call* call) = 0;
+};
+}  // namespace internal
+
+/// Descriptor of an RPC service and its various RPC methods
+class Service {
+ public:
+  Service() : server_(nullptr) {}
+  virtual ~Service() {}
+
+  bool has_async_methods() const {
+    for (const auto& method : methods_) {
+      if (method && method->handler() == nullptr) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  bool has_synchronous_methods() const {
+    for (const auto& method : methods_) {
+      if (method &&
+          method->api_type() == internal::RpcServiceMethod::ApiType::SYNC) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  bool has_callback_methods() const {
+    for (const auto& method : methods_) {
+      if (method && (method->api_type() ==
+                         internal::RpcServiceMethod::ApiType::CALL_BACK ||
+                     method->api_type() ==
+                         internal::RpcServiceMethod::ApiType::RAW_CALL_BACK)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  bool has_generic_methods() const {
+    for (const auto& method : methods_) {
+      if (method == nullptr) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+ protected:
+  template <class Message>
+  void RequestAsyncUnary(int index, grpc::ServerContext* context,
+                         Message* request,
+                         internal::ServerAsyncStreamingInterface* stream,
+                         grpc::CompletionQueue* call_cq,
+                         grpc::ServerCompletionQueue* notification_cq,
+                         void* tag) {
+    // Typecast the index to size_t for indexing into a vector
+    // while preserving the API that existed before a compiler
+    // warning was first seen (grpc/grpc#11664)
+    size_t idx = static_cast<size_t>(index);
+    server_->RequestAsyncCall(methods_[idx].get(), context, stream, call_cq,
+                              notification_cq, tag, request);
+  }
+  void RequestAsyncClientStreaming(
+      int index, grpc::ServerContext* context,
+      internal::ServerAsyncStreamingInterface* stream,
+      grpc::CompletionQueue* call_cq,
+      grpc::ServerCompletionQueue* notification_cq, void* tag) {
+    size_t idx = static_cast<size_t>(index);
+    server_->RequestAsyncCall(methods_[idx].get(), context, stream, call_cq,
+                              notification_cq, tag);
+  }
+  template <class Message>
+  void RequestAsyncServerStreaming(
+      int index, grpc::ServerContext* context, Message* request,
+      internal::ServerAsyncStreamingInterface* stream,
+      grpc::CompletionQueue* call_cq,
+      grpc::ServerCompletionQueue* notification_cq, void* tag) {
+    size_t idx = static_cast<size_t>(index);
+    server_->RequestAsyncCall(methods_[idx].get(), context, stream, call_cq,
+                              notification_cq, tag, request);
+  }
+  void RequestAsyncBidiStreaming(
+      int index, grpc::ServerContext* context,
+      internal::ServerAsyncStreamingInterface* stream,
+      grpc::CompletionQueue* call_cq,
+      grpc::ServerCompletionQueue* notification_cq, void* tag) {
+    size_t idx = static_cast<size_t>(index);
+    server_->RequestAsyncCall(methods_[idx].get(), context, stream, call_cq,
+                              notification_cq, tag);
+  }
+
+  void AddMethod(internal::RpcServiceMethod* method) {
+    methods_.emplace_back(method);
+  }
+
+  void MarkMethodAsync(int index) {
+    // This does not have to be a hard error, however no one has approached us
+    // with a use case yet. Please file an issue if you believe you have one.
+    size_t idx = static_cast<size_t>(index);
+    GPR_ASSERT(methods_[idx].get() != nullptr &&
+               "Cannot mark the method as 'async' because it has already been "
+               "marked as 'generic'.");
+    methods_[idx]->SetServerApiType(internal::RpcServiceMethod::ApiType::ASYNC);
+  }
+
+  void MarkMethodRaw(int index) {
+    // This does not have to be a hard error, however no one has approached us
+    // with a use case yet. Please file an issue if you believe you have one.
+    size_t idx = static_cast<size_t>(index);
+    GPR_ASSERT(methods_[idx].get() != nullptr &&
+               "Cannot mark the method as 'raw' because it has already "
+               "been marked as 'generic'.");
+    methods_[idx]->SetServerApiType(internal::RpcServiceMethod::ApiType::RAW);
+  }
+
+  void MarkMethodGeneric(int index) {
+    // This does not have to be a hard error, however no one has approached us
+    // with a use case yet. Please file an issue if you believe you have one.
+    size_t idx = static_cast<size_t>(index);
+    GPR_ASSERT(
+        methods_[idx]->handler() != nullptr &&
+        "Cannot mark the method as 'generic' because it has already been "
+        "marked as 'async' or 'raw'.");
+    methods_[idx].reset();
+  }
+
+  void MarkMethodStreamed(int index, internal::MethodHandler* streamed_method) {
+    // This does not have to be a hard error, however no one has approached us
+    // with a use case yet. Please file an issue if you believe you have one.
+    size_t idx = static_cast<size_t>(index);
+    GPR_ASSERT(methods_[idx] && methods_[idx]->handler() &&
+               "Cannot mark an async or generic method Streamed");
+    methods_[idx]->SetHandler(streamed_method);
+
+    // From the server's point of view, streamed unary is a special
+    // case of BIDI_STREAMING that has 1 read and 1 write, in that order,
+    // and split server-side streaming is BIDI_STREAMING with 1 read and
+    // any number of writes, in that order.
+    methods_[idx]->SetMethodType(internal::RpcMethod::BIDI_STREAMING);
+  }
+
+  void MarkMethodCallback(int index, internal::MethodHandler* handler) {
+    // This does not have to be a hard error, however no one has approached us
+    // with a use case yet. Please file an issue if you believe you have one.
+    size_t idx = static_cast<size_t>(index);
+    GPR_ASSERT(
+        methods_[idx].get() != nullptr &&
+        "Cannot mark the method as 'callback' because it has already been "
+        "marked as 'generic'.");
+    methods_[idx]->SetHandler(handler);
+    methods_[idx]->SetServerApiType(
+        internal::RpcServiceMethod::ApiType::CALL_BACK);
+  }
+
+  void MarkMethodRawCallback(int index, internal::MethodHandler* handler) {
+    // This does not have to be a hard error, however no one has approached us
+    // with a use case yet. Please file an issue if you believe you have one.
+    size_t idx = static_cast<size_t>(index);
+    GPR_ASSERT(
+        methods_[idx].get() != nullptr &&
+        "Cannot mark the method as 'raw callback' because it has already "
+        "been marked as 'generic'.");
+    methods_[idx]->SetHandler(handler);
+    methods_[idx]->SetServerApiType(
+        internal::RpcServiceMethod::ApiType::RAW_CALL_BACK);
+  }
+
+  internal::MethodHandler* GetHandler(int index) {
+    size_t idx = static_cast<size_t>(index);
+    return methods_[idx]->handler();
+  }
+
+ private:
+  friend class Server;
+  friend class ServerInterface;
+  ServerInterface* server_;
+  std::vector<std::unique_ptr<internal::RpcServiceMethod>> methods_;
+};
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SERVICE_TYPE_H

Pods/gRPC-C++/include/grpcpp/impl/status.h

@@ -0,0 +1,141 @@
+//
+//
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_STATUS_H
+#define GRPCPP_IMPL_STATUS_H
+
+// IWYU pragma: private, include <grpcpp/support/status.h>
+
+#include <grpc/support/port_platform.h>
+
+#include <grpc/status.h>
+#include <grpcpp/support/config.h>
+#include <grpcpp/support/status_code_enum.h>
+
+namespace grpc {
+
+/// Did it work? If it didn't, why?
+///
+/// See \a grpc::StatusCode for details on the available code and their meaning.
+class GRPC_MUST_USE_RESULT_WHEN_USE_STRICT_WARNING GRPCXX_DLL Status {
+ public:
+  /// Construct an OK instance.
+  Status() : code_(StatusCode::OK) {
+    // Static assertions to make sure that the C++ API value correctly
+    // maps to the core surface API value
+    static_assert(StatusCode::OK == static_cast<StatusCode>(GRPC_STATUS_OK),
+                  "Mismatched status code");
+    static_assert(
+        StatusCode::CANCELLED == static_cast<StatusCode>(GRPC_STATUS_CANCELLED),
+        "Mismatched status code");
+    static_assert(
+        StatusCode::UNKNOWN == static_cast<StatusCode>(GRPC_STATUS_UNKNOWN),
+        "Mismatched status code");
+    static_assert(StatusCode::INVALID_ARGUMENT ==
+                      static_cast<StatusCode>(GRPC_STATUS_INVALID_ARGUMENT),
+                  "Mismatched status code");
+    static_assert(StatusCode::DEADLINE_EXCEEDED ==
+                      static_cast<StatusCode>(GRPC_STATUS_DEADLINE_EXCEEDED),
+                  "Mismatched status code");
+    static_assert(
+        StatusCode::NOT_FOUND == static_cast<StatusCode>(GRPC_STATUS_NOT_FOUND),
+        "Mismatched status code");
+    static_assert(StatusCode::ALREADY_EXISTS ==
+                      static_cast<StatusCode>(GRPC_STATUS_ALREADY_EXISTS),
+                  "Mismatched status code");
+    static_assert(StatusCode::PERMISSION_DENIED ==
+                      static_cast<StatusCode>(GRPC_STATUS_PERMISSION_DENIED),
+                  "Mismatched status code");
+    static_assert(StatusCode::UNAUTHENTICATED ==
+                      static_cast<StatusCode>(GRPC_STATUS_UNAUTHENTICATED),
+                  "Mismatched status code");
+    static_assert(StatusCode::RESOURCE_EXHAUSTED ==
+                      static_cast<StatusCode>(GRPC_STATUS_RESOURCE_EXHAUSTED),
+                  "Mismatched status code");
+    static_assert(StatusCode::FAILED_PRECONDITION ==
+                      static_cast<StatusCode>(GRPC_STATUS_FAILED_PRECONDITION),
+                  "Mismatched status code");
+    static_assert(
+        StatusCode::ABORTED == static_cast<StatusCode>(GRPC_STATUS_ABORTED),
+        "Mismatched status code");
+    static_assert(StatusCode::OUT_OF_RANGE ==
+                      static_cast<StatusCode>(GRPC_STATUS_OUT_OF_RANGE),
+                  "Mismatched status code");
+    static_assert(StatusCode::UNIMPLEMENTED ==
+                      static_cast<StatusCode>(GRPC_STATUS_UNIMPLEMENTED),
+                  "Mismatched status code");
+    static_assert(
+        StatusCode::INTERNAL == static_cast<StatusCode>(GRPC_STATUS_INTERNAL),
+        "Mismatched status code");
+    static_assert(StatusCode::UNAVAILABLE ==
+                      static_cast<StatusCode>(GRPC_STATUS_UNAVAILABLE),
+                  "Mismatched status code");
+    static_assert(
+        StatusCode::DATA_LOSS == static_cast<StatusCode>(GRPC_STATUS_DATA_LOSS),
+        "Mismatched status code");
+  }
+
+  /// Construct an instance with associated \a code and \a error_message.
+  /// It is an error to construct an OK status with non-empty \a error_message.
+  /// Note that \a message is intentionally accepted as a const reference
+  /// instead of a value (which results in a copy instead of a move) to allow
+  /// for easy transition to absl::Status in the future which accepts an
+  /// absl::string_view as a parameter.
+  Status(StatusCode code, const std::string& error_message)
+      : code_(code), error_message_(error_message) {}
+
+  /// Construct an instance with \a code,  \a error_message and
+  /// \a error_details. It is an error to construct an OK status with non-empty
+  /// \a error_message and/or \a error_details.
+  Status(StatusCode code, const std::string& error_message,
+         const std::string& error_details)
+      : code_(code),
+        error_message_(error_message),
+        binary_error_details_(error_details) {}
+
+  // Pre-defined special status objects.
+  /// An OK pre-defined instance.
+  static const Status& OK;
+  /// A CANCELLED pre-defined instance.
+  static const Status& CANCELLED;
+
+  /// Return the instance's error code.
+  StatusCode error_code() const { return code_; }
+  /// Return the instance's error message.
+  std::string error_message() const { return error_message_; }
+  /// Return the (binary) error details.
+  // Usually it contains a serialized google.rpc.Status proto.
+  std::string error_details() const { return binary_error_details_; }
+
+  /// Is the status OK?
+  bool ok() const { return code_ == StatusCode::OK; }
+
+  // Ignores any errors. This method does nothing except potentially suppress
+  // complaints from any tools that are checking that errors are not dropped on
+  // the floor.
+  void IgnoreError() const {}
+
+ private:
+  StatusCode code_;
+  std::string error_message_;
+  std::string binary_error_details_;
+};
+
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_STATUS_H

Pods/gRPC-C++/include/grpcpp/impl/sync.h

@@ -0,0 +1,150 @@
+//
+//
+// Copyright 2019 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPCPP_IMPL_SYNC_H
+#define GRPCPP_IMPL_SYNC_H
+
+#include <grpc/support/port_platform.h>
+
+#ifdef GPR_HAS_PTHREAD_H
+#include <pthread.h>
+#endif
+
+#include <mutex>
+
+#include "absl/synchronization/mutex.h"
+
+#include <grpc/support/log.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/time.h>
+
+// The core library is not accessible in C++ codegen headers, and vice versa.
+// Thus, we need to have duplicate headers with similar functionality.
+// Make sure any change to this file is also reflected in
+// src/core/lib/gprpp/sync.h too.
+//
+// Whenever possible, prefer "src/core/lib/gprpp/sync.h" over this file,
+// since in core we do not rely on g_core_codegen_interface and hence do not
+// pay the costs of virtual function calls.
+
+namespace grpc {
+namespace internal {
+
+#ifdef GPR_ABSEIL_SYNC
+
+using Mutex = absl::Mutex;
+using MutexLock = absl::MutexLock;
+using ReleasableMutexLock = absl::ReleasableMutexLock;
+using CondVar = absl::CondVar;
+
+#else
+
+class ABSL_LOCKABLE Mutex {
+ public:
+  Mutex() { gpr_mu_init(&mu_); }
+  ~Mutex() { gpr_mu_destroy(&mu_); }
+
+  Mutex(const Mutex&) = delete;
+  Mutex& operator=(const Mutex&) = delete;
+
+  void Lock() ABSL_EXCLUSIVE_LOCK_FUNCTION() { gpr_mu_lock(&mu_); }
+  void Unlock() ABSL_UNLOCK_FUNCTION() { gpr_mu_unlock(&mu_); }
+
+ private:
+  union {
+    gpr_mu mu_;
+    std::mutex do_not_use_sth_;
+#ifdef GPR_HAS_PTHREAD_H
+    pthread_mutex_t do_not_use_pth_;
+#endif
+  };
+
+  friend class CondVar;
+};
+
+class ABSL_SCOPED_LOCKABLE MutexLock {
+ public:
+  explicit MutexLock(Mutex* mu) ABSL_EXCLUSIVE_LOCK_FUNCTION(mu) : mu_(mu) {
+    mu_->Lock();
+  }
+  ~MutexLock() ABSL_UNLOCK_FUNCTION() { mu_->Unlock(); }
+
+  MutexLock(const MutexLock&) = delete;
+  MutexLock& operator=(const MutexLock&) = delete;
+
+ private:
+  Mutex* const mu_;
+};
+
+class ABSL_SCOPED_LOCKABLE ReleasableMutexLock {
+ public:
+  explicit ReleasableMutexLock(Mutex* mu) ABSL_EXCLUSIVE_LOCK_FUNCTION(mu)
+      : mu_(mu) {
+    mu_->Lock();
+  }
+  ~ReleasableMutexLock() ABSL_UNLOCK_FUNCTION() {
+    if (!released_) mu_->Unlock();
+  }
+
+  ReleasableMutexLock(const ReleasableMutexLock&) = delete;
+  ReleasableMutexLock& operator=(const ReleasableMutexLock&) = delete;
+
+  void Release() ABSL_UNLOCK_FUNCTION() {
+    GPR_DEBUG_ASSERT(!released_);
+    released_ = true;
+    mu_->Unlock();
+  }
+
+ private:
+  Mutex* const mu_;
+  bool released_ = false;
+};
+
+class CondVar {
+ public:
+  CondVar() { gpr_cv_init(&cv_); }
+  ~CondVar() { gpr_cv_destroy(&cv_); }
+
+  CondVar(const CondVar&) = delete;
+  CondVar& operator=(const CondVar&) = delete;
+
+  void Signal() { gpr_cv_signal(&cv_); }
+  void SignalAll() { gpr_cv_broadcast(&cv_); }
+
+  void Wait(Mutex* mu) {
+    gpr_cv_wait(&cv_, &mu->mu_, gpr_inf_future(GPR_CLOCK_REALTIME));
+  }
+
+ private:
+  gpr_cv cv_;
+};
+
+#endif  // GPR_ABSEIL_SYNC
+
+template <typename Predicate>
+GRPC_DEPRECATED("incompatible with thread safety analysis")
+static void WaitUntil(CondVar* cv, Mutex* mu, Predicate pred) {
+  while (!pred()) {
+    cv->Wait(mu);
+  }
+}
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_SYNC_H