1 /* 2 * Copyright (c) 2012 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 #ifndef WEBRTC_MODULES_INCLUDE_MODULE_H_ 12 #define WEBRTC_MODULES_INCLUDE_MODULE_H_ 13 14 #include "webrtc/typedefs.h" 15 16 namespace webrtc { 17 18 class ProcessThread; 19 20 class Module { 21 public: 22 // Returns the number of milliseconds until the module wants a worker 23 // thread to call Process. 24 // This method is called on the same worker thread as Process will 25 // be called on. 26 // TODO(tommi): Almost all implementations of this function, need to know 27 // the current tick count. Consider passing it as an argument. It could 28 // also improve the accuracy of when the next callback occurs since the 29 // thread that calls Process() will also have it's tick count reference 30 // which might not match with what the implementations use. 31 virtual int64_t TimeUntilNextProcess() = 0; 32 33 // Process any pending tasks such as timeouts. 34 // Called on a worker thread. 35 virtual int32_t Process() = 0; 36 37 // This method is called when the module is attached to a *running* process 38 // thread or detached from one. In the case of detaching, |process_thread| 39 // will be nullptr. 40 // 41 // This method will be called in the following cases: 42 // 43 // * Non-null process_thread: 44 // * ProcessThread::RegisterModule() is called while the thread is running. 45 // * ProcessThread::Start() is called and RegisterModule has previously 46 // been called. The thread will be started immediately after notifying 47 // all modules. 48 // 49 // * Null process_thread: 50 // * ProcessThread::DeRegisterModule() is called while the thread is 51 // running. 52 // * ProcessThread::Stop() was called and the thread has been stopped. 53 // 54 // NOTE: This method is not called from the worker thread itself, but from 55 // the thread that registers/deregisters the module or calls Start/Stop. 56 virtual void ProcessThreadAttached(ProcessThread* process_thread) {} 57 58 protected: 59 virtual ~Module() {} 60 }; 61 62 // Reference counted version of the Module interface. 63 class RefCountedModule : public Module { 64 public: 65 // Increase the reference count by one. 66 // Returns the incremented reference count. 67 virtual int32_t AddRef() const = 0; 68 69 // Decrease the reference count by one. 70 // Returns the decreased reference count. 71 // Returns 0 if the last reference was just released. 72 // When the reference count reaches 0 the object will self-destruct. 73 virtual int32_t Release() const = 0; 74 75 protected: 76 ~RefCountedModule() override = default; 77 }; 78 79 } // namespace webrtc 80 81 #endif // WEBRTC_MODULES_INCLUDE_MODULE_H_ 82
