/* * Copyright (c) 2017 Cisco and/or its affiliates. * 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 __VOM_EVENT_CMD_H__ #define __VOM_EVENT_CMD_H__ #include <mutex> #include "vom/rpc_cmd.hpp" #include <vapi/vapi.hpp> namespace VOM { /** * An Event command base class. * Events are one of the sub-set of command type to VPP. * A client performs a one time 'registration/subsription' to VPP for the * event in question and then is notified asynchronously when those events * occur. * The model here then is that the lifetime of the event command represensts * the during of the clients subscription. When the command is 'issued' the * subscription begins, when it is 'retired' the subscription ends. For the * subscription duration the client will be notified as events are recieved. * The client can then 'pop' these events from this command object. */ template <typename WANT, typename EVENT> class event_cmd : public rpc_cmd<HW::item<bool>, rc_t, WANT> { public: /** * Default constructor */ event_cmd(HW::item<bool>& b) : rpc_cmd<HW::item<bool>, rc_t, WANT>(b) { } /** * Default destructor */ virtual ~event_cmd() {} /** * Typedef for the event type */ typedef typename vapi::Event_registration<EVENT>::resp_type event_t; typedef typename vapi::Event_registration<EVENT> reg_t; typedef typename vapi::Result_set<typename reg_t::resp_type>::const_iterator const_iterator; const_iterator begin() { return (m_reg->get_result_set().begin()); } const_iterator end() { return (m_reg->get_result_set().end()); } void lock() { m_mutex.lock(); } void unlock() { m_mutex.unlock(); } /** * flush/free all the events thus far reeived. * Call with the lock held! */ void flush() { m_reg->get_result_set().free_all_responses(); } /** * Retire the command. This is only appropriate for Event Commands * As they persist until retired. */ virtual void retire(connection& con) = 0; vapi_error_e operator()(reg_t& dl) { notify(); return (VAPI_OK); } protected: /** * Notify the command that data from VPP has arrived and been stored. * The command should now inform its clients/listeners. */ virtual void notify() = 0; /** * The VAPI event registration */ std::unique_ptr<vapi::Event_registration<EVENT>> m_reg; /** * Mutex protection for the events */ std::mutex m_mutex; }; }; /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "mozilla") * End: */ #endif