Mathias Agopian | 2bd9959 | 2012-02-25 23:02:14 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 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 | |
| 17 | #ifndef _LIBS_UTILS_THREAD_H |
| 18 | #define _LIBS_UTILS_THREAD_H |
| 19 | |
| 20 | #include <stdint.h> |
| 21 | #include <sys/types.h> |
| 22 | #include <time.h> |
| 23 | |
Yabin Cui | 4a6e5a3 | 2015-01-26 19:48:54 -0800 | [diff] [blame] | 24 | #if !defined(_WIN32) |
Mathias Agopian | 2bd9959 | 2012-02-25 23:02:14 -0800 | [diff] [blame] | 25 | # include <pthread.h> |
| 26 | #endif |
| 27 | |
| 28 | #include <utils/Condition.h> |
| 29 | #include <utils/Errors.h> |
| 30 | #include <utils/Mutex.h> |
| 31 | #include <utils/RefBase.h> |
| 32 | #include <utils/Timers.h> |
| 33 | #include <utils/ThreadDefs.h> |
| 34 | |
| 35 | // --------------------------------------------------------------------------- |
| 36 | namespace android { |
| 37 | // --------------------------------------------------------------------------- |
| 38 | |
| 39 | class Thread : virtual public RefBase |
| 40 | { |
| 41 | public: |
| 42 | // Create a Thread object, but doesn't create or start the associated |
| 43 | // thread. See the run() method. |
| 44 | Thread(bool canCallJava = true); |
| 45 | virtual ~Thread(); |
| 46 | |
| 47 | // Start the thread in threadLoop() which needs to be implemented. |
Brian Carlstrom | e71b914 | 2016-03-12 16:08:12 -0800 | [diff] [blame^] | 48 | virtual status_t run( const char* name, |
Mathias Agopian | 2bd9959 | 2012-02-25 23:02:14 -0800 | [diff] [blame] | 49 | int32_t priority = PRIORITY_DEFAULT, |
| 50 | size_t stack = 0); |
| 51 | |
| 52 | // Ask this object's thread to exit. This function is asynchronous, when the |
| 53 | // function returns the thread might still be running. Of course, this |
| 54 | // function can be called from a different thread. |
| 55 | virtual void requestExit(); |
| 56 | |
| 57 | // Good place to do one-time initializations |
| 58 | virtual status_t readyToRun(); |
| 59 | |
| 60 | // Call requestExit() and wait until this object's thread exits. |
| 61 | // BE VERY CAREFUL of deadlocks. In particular, it would be silly to call |
| 62 | // this function from this object's thread. Will return WOULD_BLOCK in |
| 63 | // that case. |
| 64 | status_t requestExitAndWait(); |
| 65 | |
| 66 | // Wait until this object's thread exits. Returns immediately if not yet running. |
| 67 | // Do not call from this object's thread; will return WOULD_BLOCK in that case. |
| 68 | status_t join(); |
| 69 | |
Romain Guy | 31ba37f | 2013-03-11 14:34:56 -0700 | [diff] [blame] | 70 | // Indicates whether this thread is running or not. |
| 71 | bool isRunning() const; |
| 72 | |
Elliott Hughes | 9b828ad | 2015-07-30 08:47:35 -0700 | [diff] [blame] | 73 | #if defined(__ANDROID__) |
Elliott Hughes | b765961 | 2014-08-18 10:47:37 -0700 | [diff] [blame] | 74 | // Return the thread's kernel ID, same as the thread itself calling gettid(), |
| 75 | // or -1 if the thread is not running. |
Mathias Agopian | 2bd9959 | 2012-02-25 23:02:14 -0800 | [diff] [blame] | 76 | pid_t getTid() const; |
| 77 | #endif |
| 78 | |
| 79 | protected: |
| 80 | // exitPending() returns true if requestExit() has been called. |
| 81 | bool exitPending() const; |
| 82 | |
| 83 | private: |
| 84 | // Derived class must implement threadLoop(). The thread starts its life |
| 85 | // here. There are two ways of using the Thread object: |
| 86 | // 1) loop: if threadLoop() returns true, it will be called again if |
| 87 | // requestExit() wasn't called. |
| 88 | // 2) once: if threadLoop() returns false, the thread will exit upon return. |
| 89 | virtual bool threadLoop() = 0; |
| 90 | |
| 91 | private: |
| 92 | Thread& operator=(const Thread&); |
| 93 | static int _threadLoop(void* user); |
| 94 | const bool mCanCallJava; |
| 95 | // always hold mLock when reading or writing |
| 96 | thread_id_t mThread; |
| 97 | mutable Mutex mLock; |
| 98 | Condition mThreadExitedCondition; |
| 99 | status_t mStatus; |
| 100 | // note that all accesses of mExitPending and mRunning need to hold mLock |
| 101 | volatile bool mExitPending; |
| 102 | volatile bool mRunning; |
| 103 | sp<Thread> mHoldSelf; |
Elliott Hughes | 9b828ad | 2015-07-30 08:47:35 -0700 | [diff] [blame] | 104 | #if defined(__ANDROID__) |
Mathias Agopian | 2bd9959 | 2012-02-25 23:02:14 -0800 | [diff] [blame] | 105 | // legacy for debugging, not used by getTid() as it is set by the child thread |
| 106 | // and so is not initialized until the child reaches that point |
| 107 | pid_t mTid; |
| 108 | #endif |
| 109 | }; |
| 110 | |
| 111 | |
| 112 | }; // namespace android |
| 113 | |
| 114 | // --------------------------------------------------------------------------- |
| 115 | #endif // _LIBS_UTILS_THREAD_H |
| 116 | // --------------------------------------------------------------------------- |