// Copyright 2024 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_SUPPORT_GLOBAL_CALLBACK_HOOK_H #define GRPCPP_SUPPORT_GLOBAL_CALLBACK_HOOK_H #include "absl/functional/function_ref.h" struct grpc_call; namespace grpc { class GlobalCallbackHook { public: virtual ~GlobalCallbackHook() = default; virtual void RunCallback(grpc_call* call, absl::FunctionRef callback) = 0; protected: // An exception-safe way of invoking a user-specified callback function. template void CatchingCallback(Func&& func, Args&&... args) { #if GRPC_ALLOW_EXCEPTIONS try { func(std::forward(args)...); } catch (...) { // nothing to return or change here, just don't crash the library } #else // GRPC_ALLOW_EXCEPTIONS func(std::forward(args)...); #endif // GRPC_ALLOW_EXCEPTIONS } }; class DefaultGlobalCallbackHook final : public GlobalCallbackHook { public: void RunCallback(grpc_call* call, absl::FunctionRef callback) override { CatchingCallback(callback); } }; std::shared_ptr GetGlobalCallbackHook(); void SetGlobalCallbackHook(GlobalCallbackHook* hook); } // namespace grpc #endif // GRPCPP_SUPPORT_GLOBAL_CALLBACK_HOOK_H