auto import from //depot/cupcake/@135843
diff --git a/include/utils/threads.h b/include/utils/threads.h
new file mode 100644
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--- /dev/null
+++ b/include/utils/threads.h
@@ -0,0 +1,347 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LIBS_UTILS_THREADS_H
+#define _LIBS_UTILS_THREADS_H
+
+#include <stdint.h>
+#include <sys/types.h>
+#include <time.h>
+
+// ------------------------------------------------------------------
+// C API
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void* android_thread_id_t;
+
+typedef int (*android_thread_func_t)(void*);
+
+enum {
+ /*
+ * ***********************************************
+ * ** Keep in sync with android.os.Process.java **
+ * ***********************************************
+ *
+ * This maps directly to the "nice" priorites we use in Android.
+ * A thread priority should be chosen inverse-proportinally to
+ * the amount of work the thread is expected to do. The more work
+ * a thread will do, the less favorable priority it should get so that
+ * it doesn't starve the system. Threads not behaving properly might
+ * be "punished" by the kernel.
+ * Use the levels below when appropriate. Intermediate values are
+ * acceptable, preferably use the {MORE|LESS}_FAVORABLE constants below.
+ */
+ ANDROID_PRIORITY_LOWEST = 19,
+
+ /* use for background tasks */
+ ANDROID_PRIORITY_BACKGROUND = 10,
+
+ /* most threads run at normal priority */
+ ANDROID_PRIORITY_NORMAL = 0,
+
+ /* threads currently running a UI that the user is interacting with */
+ ANDROID_PRIORITY_FOREGROUND = -2,
+
+ /* the main UI thread has a slightly more favorable priority */
+ ANDROID_PRIORITY_DISPLAY = -4,
+
+ /* ui service treads might want to run at a urgent display (uncommon) */
+ ANDROID_PRIORITY_URGENT_DISPLAY = -8,
+
+ /* all normal audio threads */
+ ANDROID_PRIORITY_AUDIO = -16,
+
+ /* service audio threads (uncommon) */
+ ANDROID_PRIORITY_URGENT_AUDIO = -19,
+
+ /* should never be used in practice. regular process might not
+ * be allowed to use this level */
+ ANDROID_PRIORITY_HIGHEST = -20,
+
+ ANDROID_PRIORITY_DEFAULT = ANDROID_PRIORITY_NORMAL,
+ ANDROID_PRIORITY_MORE_FAVORABLE = -1,
+ ANDROID_PRIORITY_LESS_FAVORABLE = +1,
+};
+
+// Create and run a new thread.
+extern int androidCreateThread(android_thread_func_t, void *);
+
+// Create thread with lots of parameters
+extern int androidCreateThreadEtc(android_thread_func_t entryFunction,
+ void *userData,
+ const char* threadName,
+ int32_t threadPriority,
+ size_t threadStackSize,
+ android_thread_id_t *threadId);
+
+// Get some sort of unique identifier for the current thread.
+extern android_thread_id_t androidGetThreadId();
+
+// Low-level thread creation -- never creates threads that can
+// interact with the Java VM.
+extern int androidCreateRawThreadEtc(android_thread_func_t entryFunction,
+ void *userData,
+ const char* threadName,
+ int32_t threadPriority,
+ size_t threadStackSize,
+ android_thread_id_t *threadId);
+
+// Used by the Java Runtime to control how threads are created, so that
+// they can be proper and lovely Java threads.
+typedef int (*android_create_thread_fn)(android_thread_func_t entryFunction,
+ void *userData,
+ const char* threadName,
+ int32_t threadPriority,
+ size_t threadStackSize,
+ android_thread_id_t *threadId);
+
+extern void androidSetCreateThreadFunc(android_create_thread_fn func);
+
+#ifdef __cplusplus
+}
+#endif
+
+// ------------------------------------------------------------------
+// C++ API
+
+#ifdef __cplusplus
+
+#include <utils/Errors.h>
+#include <utils/RefBase.h>
+#include <utils/Timers.h>
+
+namespace android {
+
+typedef android_thread_id_t thread_id_t;
+
+typedef android_thread_func_t thread_func_t;
+
+enum {
+ PRIORITY_LOWEST = ANDROID_PRIORITY_LOWEST,
+ PRIORITY_BACKGROUND = ANDROID_PRIORITY_BACKGROUND,
+ PRIORITY_NORMAL = ANDROID_PRIORITY_NORMAL,
+ PRIORITY_FOREGROUND = ANDROID_PRIORITY_FOREGROUND,
+ PRIORITY_DISPLAY = ANDROID_PRIORITY_DISPLAY,
+ PRIORITY_URGENT_DISPLAY = ANDROID_PRIORITY_URGENT_DISPLAY,
+ PRIORITY_AUDIO = ANDROID_PRIORITY_AUDIO,
+ PRIORITY_URGENT_AUDIO = ANDROID_PRIORITY_URGENT_AUDIO,
+ PRIORITY_HIGHEST = ANDROID_PRIORITY_HIGHEST,
+ PRIORITY_DEFAULT = ANDROID_PRIORITY_DEFAULT,
+ PRIORITY_MORE_FAVORABLE = ANDROID_PRIORITY_MORE_FAVORABLE,
+ PRIORITY_LESS_FAVORABLE = ANDROID_PRIORITY_LESS_FAVORABLE,
+};
+
+// Create and run a new thread.
+inline bool createThread(thread_func_t f, void *a) {
+ return androidCreateThread(f, a) ? true : false;
+}
+
+// Create thread with lots of parameters
+inline bool createThreadEtc(thread_func_t entryFunction,
+ void *userData,
+ const char* threadName = "android:unnamed_thread",
+ int32_t threadPriority = PRIORITY_DEFAULT,
+ size_t threadStackSize = 0,
+ thread_id_t *threadId = 0)
+{
+ return androidCreateThreadEtc(entryFunction, userData, threadName,
+ threadPriority, threadStackSize, threadId) ? true : false;
+}
+
+// Get some sort of unique identifier for the current thread.
+inline thread_id_t getThreadId() {
+ return androidGetThreadId();
+}
+
+/*
+ * Simple mutex class. The implementation is system-dependent.
+ *
+ * The mutex must be unlocked by the thread that locked it. They are not
+ * recursive, i.e. the same thread can't lock it multiple times.
+ */
+class Mutex {
+public:
+ Mutex();
+ Mutex(const char* name);
+ ~Mutex();
+
+ // lock or unlock the mutex
+ status_t lock();
+ void unlock();
+
+ // lock if possible; returns 0 on success, error otherwise
+ status_t tryLock();
+
+ // Manages the mutex automatically. It'll be locked when Autolock is
+ // constructed and released when Autolock goes out of scope.
+ class Autolock {
+ public:
+ inline Autolock(Mutex& mutex) : mpMutex(&mutex) { mutex.lock(); }
+ inline Autolock(Mutex* mutex) : mpMutex(mutex) { mutex->lock(); }
+ inline ~Autolock() { mpMutex->unlock(); }
+ private:
+ Mutex* mpMutex;
+ };
+
+private:
+ friend class Condition;
+
+ // A mutex cannot be copied
+ Mutex(const Mutex&);
+ Mutex& operator = (const Mutex&);
+ void _init();
+
+ void* mState;
+};
+
+/*
+ * Automatic mutex. Declare one of these at the top of a function.
+ * When the function returns, it will go out of scope, and release the
+ * mutex.
+ */
+
+typedef Mutex::Autolock AutoMutex;
+
+
+/*
+ * Condition variable class. The implementation is system-dependent.
+ *
+ * Condition variables are paired up with mutexes. Lock the mutex,
+ * call wait(), then either re-wait() if things aren't quite what you want,
+ * or unlock the mutex and continue. All threads calling wait() must
+ * use the same mutex for a given Condition.
+ */
+class Condition {
+public:
+ Condition();
+ ~Condition();
+ // Wait on the condition variable. Lock the mutex before calling.
+ status_t wait(Mutex& mutex);
+ // Wait on the condition variable until the given time. Lock the mutex
+ // before calling.
+ status_t wait(Mutex& mutex, nsecs_t abstime);
+ // same with relative timeout
+ status_t waitRelative(Mutex& mutex, nsecs_t reltime);
+ // Signal the condition variable, allowing one thread to continue.
+ void signal();
+ // Signal the condition variable, allowing all threads to continue.
+ void broadcast();
+
+private:
+ void* mState;
+};
+
+
+/*
+ * Read/write lock. The resource can have multiple readers or one writer,
+ * but can't be read and written at the same time.
+ *
+ * The same thread should not call a lock function while it already has
+ * a lock. (Should be okay for multiple readers.)
+ */
+class ReadWriteLock {
+public:
+ ReadWriteLock()
+ : mNumReaders(0), mNumWriters(0)
+ {}
+ ~ReadWriteLock() {}
+
+ void lockForRead();
+ bool tryLockForRead();
+ void unlockForRead();
+
+ void lockForWrite();
+ bool tryLockForWrite();
+ void unlockForWrite();
+
+private:
+ int mNumReaders;
+ int mNumWriters;
+
+ Mutex mLock;
+ Condition mReadWaiter;
+ Condition mWriteWaiter;
+#if defined(PRINT_RENDER_TIMES)
+ DurationTimer mDebugTimer;
+#endif
+};
+
+
+/*
+ * This is our spiffy thread object!
+ */
+
+class Thread : virtual public RefBase
+{
+public:
+ // Create a Thread object, but doesn't create or start the associated
+ // thread. See the run() method.
+ Thread(bool canCallJava = true);
+ virtual ~Thread();
+
+ // Start the thread in threadLoop() which needs to be implemented.
+ virtual status_t run( const char* name = 0,
+ int32_t priority = PRIORITY_DEFAULT,
+ size_t stack = 0);
+
+ // Ask this object's thread to exit. This function is asynchronous, when the
+ // function returns the thread might still be running. Of course, this
+ // function can be called from a different thread.
+ virtual void requestExit();
+
+ // Good place to do one-time initializations
+ virtual status_t readyToRun();
+
+ // Call requestExit() and wait until this object's thread exits.
+ // BE VERY CAREFUL of deadlocks. In particular, it would be silly to call
+ // this function from this object's thread. Will return WOULD_BLOCK in
+ // that case.
+ status_t requestExitAndWait();
+
+protected:
+ // exitPending() returns true if requestExit() has been called.
+ bool exitPending() const;
+
+private:
+ // Derived class must implemtent threadLoop(). The thread starts its life
+ // here. There are two ways of using the Thread object:
+ // 1) loop: if threadLoop() returns true, it will be called again if
+ // requestExit() wasn't called.
+ // 2) once: if threadLoop() returns false, the thread will exit upon return.
+ virtual bool threadLoop() = 0;
+
+private:
+ Thread& operator=(const Thread&);
+ static int _threadLoop(void* user);
+ const bool mCanCallJava;
+ thread_id_t mThread;
+ Mutex mLock;
+ Condition mThreadExitedCondition;
+ status_t mStatus;
+ volatile bool mExitPending;
+ volatile bool mRunning;
+ sp<Thread> mHoldSelf;
+};
+
+
+}; // namespace android
+
+#endif // __cplusplus
+
+#endif // _LIBS_UTILS_THREADS_H