1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #pragma once 17 18 #include <memory> 19 #include <mutex> 20 #include <thread> 21 #include <vector> 22 23 #include <common/libs/utils/subprocess.h> 24 25 namespace cvd { 26 27 struct MonitorEntry; 28 using OnSocketReadyCb = std::function<bool(MonitorEntry*)>; 29 30 struct MonitorEntry { 31 std::unique_ptr<Command> cmd; 32 std::unique_ptr<Subprocess> proc; 33 OnSocketReadyCb on_control_socket_ready_cb; 34 }; 35 36 // Keeps track of launched subprocesses, restarts them if they unexpectedly exit 37 class ProcessMonitor { 38 public: 39 ProcessMonitor(); 40 // Starts a managed subprocess with a controlling socket. The 41 // on_control_socket_ready_cb callback will be called when data is ready to be 42 // read from the socket or the subprocess has ended. No member functions of 43 // the process monitor object should be called from the callback as it may 44 // lead to a dealock. If the callback returns false the subprocess will no 45 // longer be monitored 46 void StartSubprocess(Command cmd, OnSocketReadyCb on_control_socket_ready_cb); 47 // Monitors an alreacy started subprocess 48 void MonitorExistingSubprocess(Command cmd, Subprocess sub_process, 49 OnSocketReadyCb on_control_socket_ready_cb); 50 static bool RestartOnExitCb(MonitorEntry* entry); 51 static bool DoNotMonitorCb(MonitorEntry* entry); 52 53 private: 54 void MonitorRoutine(); 55 56 std::vector<MonitorEntry> monitored_processes_; 57 // Used for communication with the restarter thread 58 cvd::SharedFD thread_comm_main_, thread_comm_monitor_; 59 std::thread monitor_thread_; 60 // Protects access to the monitored_processes_ 61 std::mutex processes_mutex_; 62 }; 63 } // namespace cvd 64
