1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 // System independant wrapper for spawning threads 12 // Note: the spawned thread will loop over the callback function until stopped. 13 // Note: The callback function is expected to return every 2 seconds or more 14 // often. 15 16 #ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_THREAD_WRAPPER_H_ 17 #define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_THREAD_WRAPPER_H_ 18 19 namespace webrtc { 20 // Object that will be passed by the spawned thread when it enters the callback 21 // function. 22 #define ThreadObj void* 23 24 // Callback function that the spawned thread will enter once spawned. 25 // A return value of false is interpreted as that the function has no 26 // more work to do and that the thread can be released. 27 typedef bool(*ThreadRunFunction)(ThreadObj); 28 29 enum ThreadPriority 30 { 31 kLowPriority = 1, 32 kNormalPriority = 2, 33 kHighPriority = 3, 34 kHighestPriority = 4, 35 kRealtimePriority = 5 36 }; 37 38 class ThreadWrapper 39 { 40 public: 41 enum {kThreadMaxNameLength = 64}; 42 ~ThreadWrapper()43 virtual ~ThreadWrapper() {}; 44 45 // Factory method. Constructor disabled. 46 // 47 // func Pointer to a, by user, specified callback function. 48 // obj Object associated with the thread. Passed in the callback 49 // function. 50 // prio Thread priority. May require root/admin rights. 51 // threadName NULL terminated thread name, will be visable in the Windows 52 // debugger. 53 static ThreadWrapper* CreateThread(ThreadRunFunction func = 0, 54 ThreadObj obj= 0, 55 ThreadPriority prio = kNormalPriority, 56 const char* threadName = 0); 57 58 // Non blocking termination of the spawned thread. Note that it is not safe 59 // to delete this class until the spawned thread has been reclaimed. 60 virtual void SetNotAlive() = 0; 61 62 // Spawns the thread. This will start the triggering of the callback 63 // function. 64 virtual bool Start(unsigned int& id) = 0; 65 66 // Sets the threads CPU affinity. CPUs are listed 0 - (number of CPUs - 1). 67 // The numbers in processorNumbers specify which CPUs are allowed to run the 68 // thread. processorNumbers should not contain any duplicates and elements 69 // should be lower than (number of CPUs - 1). amountOfProcessors should be 70 // equal to the number of processors listed in processorNumbers SetAffinity(const int *,const unsigned int)71 virtual bool SetAffinity(const int* /*processorNumbers*/, 72 const unsigned int /*amountOfProcessors*/) 73 {return false;} 74 75 // Stops the spawned thread and waits for it to be reclaimed with a timeout 76 // of two seconds. Will return false if the thread was not reclaimed. 77 // Multiple tries to Stop are allowed (e.g. to wait longer than 2 seconds). 78 // It's ok to call Stop() even if the spawned thread has been reclaimed. 79 virtual bool Stop() = 0; 80 81 // Stops the spawned thread dead in its tracks. Will likely result in a 82 // corrupt state. There should be an extremely good reason for even looking 83 // at this function. Can cause many problems deadlock being one of them. Shutdown()84 virtual bool Shutdown() {return false;} 85 }; 86 } // namespace webrtc 87 88 #endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_THREAD_WRAPPER_H_ 89