split utils/threads.h into multiple headers

AndroidDefs.h - C/C++ enums and types
Mutex.h - Mutex class declaration
Condition.h - Condition class declaration
RWLock.h - RWLock class declaration
Thread.h - Thread class declaration
AndroidThreads.h - low-level thread creation functions
threads.h - includes all the above for backward source compatibility

Change-Id: Ia2f80c175333b59a41d1720985810bb2346e94cb
Note: implementations are still in Threads.cpp

1 files changed, 113 insertions, 0 deletions

diff --git a/include/utils/Thread.h b/include/utils/Thread.h
new file mode 100644
index 0000000..4a34abd
--- /dev/null
+++ b/include/utils/Thread.h
@@ -0,0 +1,113 @@
+/*
+ * 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_THREAD_H
+#define _LIBS_UTILS_THREAD_H
+
+#include <stdint.h>
+#include <sys/types.h>
+#include <time.h>
+
+#if defined(HAVE_PTHREADS)
+# include <pthread.h>
+#endif
+
+#include <utils/Condition.h>
+#include <utils/Errors.h>
+#include <utils/Mutex.h>
+#include <utils/RefBase.h>
+#include <utils/Timers.h>
+#include <utils/ThreadDefs.h>
+
+// ---------------------------------------------------------------------------
+namespace android {
+// ---------------------------------------------------------------------------
+
+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();
+
+    // Wait until this object's thread exits. Returns immediately if not yet running.
+    // Do not call from this object's thread; will return WOULD_BLOCK in that case.
+            status_t    join();
+
+#ifdef HAVE_ANDROID_OS
+    // Return the thread's kernel ID, same as the thread itself calling gettid() or
+    // androidGetTid(), or -1 if the thread is not running.
+            pid_t       getTid() const;
+#endif
+
+protected:
+    // exitPending() returns true if requestExit() has been called.
+            bool        exitPending() const;
+    
+private:
+    // Derived class must implement 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;
+    // always hold mLock when reading or writing
+            thread_id_t     mThread;
+    mutable Mutex           mLock;
+            Condition       mThreadExitedCondition;
+            status_t        mStatus;
+    // note that all accesses of mExitPending and mRunning need to hold mLock
+    volatile bool           mExitPending;
+    volatile bool           mRunning;
+            sp<Thread>      mHoldSelf;
+#ifdef HAVE_ANDROID_OS
+    // legacy for debugging, not used by getTid() as it is set by the child thread
+    // and so is not initialized until the child reaches that point
+            pid_t           mTid;
+#endif
+};
+
+
+}; // namespace android
+
+// ---------------------------------------------------------------------------
+#endif // _LIBS_UTILS_THREAD_H
+// ---------------------------------------------------------------------------