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 #include "common_types.h" 20 #include "typedefs.h" 21 22 namespace webrtc { 23 // Object that will be passed by the spawned thread when it enters the callback 24 // function. 25 #define ThreadObj void* 26 27 // Callback function that the spawned thread will enter once spawned. 28 // A return value of false is interpreted as that the function has no 29 // more work to do and that the thread can be released. 30 typedef bool(*ThreadRunFunction)(ThreadObj); 31 32 enum ThreadPriority 33 { 34 kLowPriority = 1, 35 kNormalPriority = 2, 36 kHighPriority = 3, 37 kHighestPriority = 4, 38 kRealtimePriority = 5 39 }; 40 41 class ThreadWrapper 42 { 43 public: 44 enum {kThreadMaxNameLength = 64}; 45 ~ThreadWrapper()46 virtual ~ThreadWrapper() {}; 47 48 // Factory method. Constructor disabled. 49 // 50 // func Pointer to a, by user, specified callback function. 51 // obj Object associated with the thread. Passed in the callback 52 // function. 53 // prio Thread priority. May require root/admin rights. 54 // threadName NULL terminated thread name, will be visable in the Windows 55 // debugger. 56 static ThreadWrapper* CreateThread(ThreadRunFunction func = 0, 57 ThreadObj obj= 0, 58 ThreadPriority prio = kNormalPriority, 59 const char* threadName = 0); 60 61 // Get the current thread's kernel thread ID. 62 static uint32_t GetThreadId(); 63 64 // Non blocking termination of the spawned thread. Note that it is not safe 65 // to delete this class until the spawned thread has been reclaimed. 66 virtual void SetNotAlive() = 0; 67 68 // Spawns the thread. This will start the triggering of the callback 69 // function. 70 virtual bool Start(unsigned int& id) = 0; 71 72 // Sets the threads CPU affinity. CPUs are listed 0 - (number of CPUs - 1). 73 // The numbers in processorNumbers specify which CPUs are allowed to run the 74 // thread. processorNumbers should not contain any duplicates and elements 75 // should be lower than (number of CPUs - 1). amountOfProcessors should be 76 // equal to the number of processors listed in processorNumbers SetAffinity(const int *,const unsigned int)77 virtual bool SetAffinity(const int* /*processorNumbers*/, 78 const unsigned int /*amountOfProcessors*/) { 79 return false; 80 } 81 82 // Stops the spawned thread and waits for it to be reclaimed with a timeout 83 // of two seconds. Will return false if the thread was not reclaimed. 84 // Multiple tries to Stop are allowed (e.g. to wait longer than 2 seconds). 85 // It's ok to call Stop() even if the spawned thread has been reclaimed. 86 virtual bool Stop() = 0; 87 88 // Stops the spawned thread dead in its tracks. Will likely result in a 89 // corrupt state. There should be an extremely good reason for even looking 90 // at this function. Can cause many problems deadlock being one of them. Shutdown()91 virtual bool Shutdown() {return false;} 92 }; 93 } // namespace webrtc 94 95 #endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_THREAD_WRAPPER_H_ 96