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