emulator/opengl: refactor Thread class.

+ Add unit test.

Change-Id: I26d84cf590f6bfff3304be3f42dc0196bcc7f6d2

15 files changed, 467 insertions, 279 deletions

diff --git a/emulator/opengl/host/libs/libOpenglRender/RenderServer.cpp b/emulator/opengl/host/libs/libOpenglRender/RenderServer.cpp
index de28f8f..53c65ee 100644
--- a/emulator/opengl/host/libs/libOpenglRender/RenderServer.cpp
+++ b/emulator/opengl/host/libs/libOpenglRender/RenderServer.cpp
@@ -77,7 +77,7 @@ RenderServer *RenderServer::create(char* addr, size_t addrLen)
     return server;
 }
 
-int RenderServer::Main()
+intptr_t RenderServer::main()
 {
     RenderThreadsSet threads;
 
@@ -146,8 +146,7 @@ int RenderServer::Main()
     for (RenderThreadsSet::iterator t = threads.begin();
          t != threads.end();
          t++) {
-        int exitStatus;
-        (*t)->wait(&exitStatus);
+        (*t)->wait(NULL);
         delete (*t);
     }
     threads.clear();
diff --git a/emulator/opengl/host/libs/libOpenglRender/RenderServer.h b/emulator/opengl/host/libs/libOpenglRender/RenderServer.h
index ff63c94..8be8a17 100644
--- a/emulator/opengl/host/libs/libOpenglRender/RenderServer.h
+++ b/emulator/opengl/host/libs/libOpenglRender/RenderServer.h
@@ -18,15 +18,15 @@
 
 #include "SocketStream.h"
 #include "emugl/common/mutex.h"
-#include "osThread.h"
+#include "emugl/common/thread.h"
 
-class RenderServer : public osUtils::Thread
+class RenderServer : public emugl::Thread
 {
 public:
     static RenderServer *create(char* addr, size_t addrLen);
     virtual ~RenderServer();
 
-    virtual int Main();
+    virtual intptr_t main();
 
     bool isExiting() const { return m_exiting; }
 
diff --git a/emulator/opengl/host/libs/libOpenglRender/RenderThread.cpp b/emulator/opengl/host/libs/libOpenglRender/RenderThread.cpp
index 19d6c1f..3dcfdb5 100644
--- a/emulator/opengl/host/libs/libOpenglRender/RenderThread.cpp
+++ b/emulator/opengl/host/libs/libOpenglRender/RenderThread.cpp
@@ -26,7 +26,7 @@
 #define STREAM_BUFFER_SIZE 4*1024*1024
 
 RenderThread::RenderThread(IOStream *stream, emugl::Mutex *lock) :
-    osUtils::Thread(),
+    emugl::Thread(),
     m_lock(lock),
     m_stream(stream),
     m_finished(false)
@@ -43,7 +43,7 @@ RenderThread *RenderThread::create(IOStream *p_stream, emugl::Mutex *lock)
     return new RenderThread(p_stream, lock);
 }
 
-int RenderThread::Main()
+intptr_t RenderThread::main()
 {
     RenderThreadInfo tInfo;
 
diff --git a/emulator/opengl/host/libs/libOpenglRender/RenderThread.h b/emulator/opengl/host/libs/libOpenglRender/RenderThread.h
index e94d782..c1f919a 100644
--- a/emulator/opengl/host/libs/libOpenglRender/RenderThread.h
+++ b/emulator/opengl/host/libs/libOpenglRender/RenderThread.h
@@ -21,9 +21,9 @@
 #include "renderControl_dec.h"
 
 #include "emugl/common/mutex.h"
-#include "osThread.h"
+#include "emugl/common/thread.h"
 
-class RenderThread : public osUtils::Thread
+class RenderThread : public emugl::Thread
 {
 public:
     static RenderThread* create(IOStream* p_stream, emugl::Mutex* mutex);
@@ -32,7 +32,7 @@ public:
 
 private:
     RenderThread(IOStream* p_stream, emugl::Mutex* mutex);
-    virtual int Main();
+    virtual intptr_t main();
 
 private:
     emugl::Mutex *m_lock;
diff --git a/emulator/opengl/host/libs/libOpenglRender/render_api.cpp b/emulator/opengl/host/libs/libOpenglRender/render_api.cpp
index 5c9ffb1..42df668 100644
--- a/emulator/opengl/host/libs/libOpenglRender/render_api.cpp
+++ b/emulator/opengl/host/libs/libOpenglRender/render_api.cpp
@@ -243,8 +243,7 @@ int stopOpenGLRenderer(void)
     else if (s_renderThread) {
 
         // wait for the thread to exit
-        int status;
-        ret = s_renderThread->wait(&status);
+        ret = s_renderThread->wait(NULL);
 
         delete s_renderThread;
         s_renderThread = NULL;
diff --git a/emulator/opengl/host/renderer/main.cpp b/emulator/opengl/host/renderer/main.cpp
index 2c3f8e2..470e692 100644
--- a/emulator/opengl/host/renderer/main.cpp
+++ b/emulator/opengl/host/renderer/main.cpp
@@ -141,7 +141,7 @@ int main(int argc, char *argv[])
     //
     // run the server listener loop
     //
-    server->Main();
+    server->main();
 #else
     //
     // on windows we need to handle messages for the
diff --git a/emulator/opengl/shared/OpenglOsUtils/Android.mk b/emulator/opengl/shared/OpenglOsUtils/Android.mk
index 42b57dd..4b1b05e 100644
--- a/emulator/opengl/shared/OpenglOsUtils/Android.mk
+++ b/emulator/opengl/shared/OpenglOsUtils/Android.mk
@@ -15,12 +15,12 @@ host_common_INCLUDES := $(LOCAL_PATH)
 ifeq ($(HOST_OS),windows)
     host_common_SRC_FILES += \
         osProcessWin.cpp \
-        osThreadWin.cpp
+
     host_common_LDLIBS += -lws2_32 -lpsapi
 else
     host_common_SRC_FILES += \
         osProcessUnix.cpp \
-        osThreadUnix.cpp
+
     host_common_LDLIBS += -ldl
 endif
 
diff --git a/emulator/opengl/shared/OpenglOsUtils/osThread.h b/emulator/opengl/shared/OpenglOsUtils/osThread.h
deleted file mode 100644
index 970396d..0000000
--- a/emulator/opengl/shared/OpenglOsUtils/osThread.h
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
-* Copyright (C) 2011 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 _OSUTILS_THREAD_H
-#define _OSUTILS_THREAD_H
-
-#ifdef _WIN32
-#include <windows.h>
-#else // !WIN32
-#include <pthread.h>
-#endif
-
-namespace osUtils {
-
-class Thread
-{
-public:
-    Thread();
-    virtual ~Thread();
-
-    virtual int Main() = 0;
-
-    bool start();
-    bool  wait(int *exitStatus);
-    bool trywait(int *exitStatus);
-
-private:
-#ifdef _WIN32
-    static DWORD WINAPI thread_main(void *p_arg);
-#else // !WIN32
-    static void* thread_main(void *p_arg);
-#endif
-
-private:
-#ifdef _WIN32
-    HANDLE m_thread;
-    DWORD m_threadId;
-#else // !WIN32
-    pthread_t m_thread;
-    int       m_exitStatus;
-    pthread_mutex_t m_lock;
-#endif
-    bool m_isRunning;
-};
-
-} // of namespace osUtils
-
-#endif
diff --git a/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp b/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp
deleted file mode 100644
index ef2bebc..0000000
--- a/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp
+++ /dev/null
@@ -1,98 +0,0 @@
-/*
-* Copyright (C) 2011 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.
-*/
-#include "osThread.h"
-
-#include "emugl/common/thread_store.h"
-
-#include <stdint.h>
-
-namespace osUtils {
-
-Thread::Thread() :
-    m_thread((pthread_t)NULL),
-    m_exitStatus(0),
-    m_isRunning(false)
-{
-    pthread_mutex_init(&m_lock, NULL);
-}
-
-Thread::~Thread()
-{
-    pthread_mutex_destroy(&m_lock);
-}
-
-bool
-Thread::start()
-{
-    pthread_mutex_lock(&m_lock);
-    m_isRunning = true;
-    int ret = pthread_create(&m_thread, NULL, Thread::thread_main, this);
-    if(ret) {
-        m_isRunning = false;
-    }
-    pthread_mutex_unlock(&m_lock);
-    return m_isRunning;
-}
-
-bool
-Thread::wait(int *exitStatus)
-{
-    if (!m_isRunning) {
-        return false;
-    }
-
-    void *retval;
-    if (pthread_join(m_thread,&retval)) {
-        return false;
-    }
-
-    if (exitStatus) {
-        *exitStatus = (int)(uintptr_t)retval;
-    }
-    return true;
-}
-
-bool
-Thread::trywait(int *exitStatus)
-{
-    bool ret = false;
-
-    pthread_mutex_lock(&m_lock);
-    if (!m_isRunning) {
-        *exitStatus = m_exitStatus;
-        ret = true;
-    }
-    pthread_mutex_unlock(&m_lock);
-    return ret;
-}
-
-void *
-Thread::thread_main(void *p_arg)
-{
-    Thread *self = (Thread *)p_arg;
-    int ret = self->Main();
-
-    pthread_mutex_lock(&self->m_lock);
-    self->m_isRunning = false;
-    self->m_exitStatus = ret;
-    pthread_mutex_unlock(&self->m_lock);
-
-    ::emugl::ThreadStore::OnThreadExit();
-    return (void*)(uintptr_t)ret;
-}
-
-} // of namespace osUtils
-
diff --git a/emulator/opengl/shared/OpenglOsUtils/osThreadWin.cpp b/emulator/opengl/shared/OpenglOsUtils/osThreadWin.cpp
deleted file mode 100644
index 1a30b97..0000000
--- a/emulator/opengl/shared/OpenglOsUtils/osThreadWin.cpp
+++ /dev/null
@@ -1,104 +0,0 @@
-/*
-* Copyright (C) 2011 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.
-*/
-#include "osThread.h"
-
-#include "emugl/common/thread_store.h"
-
-namespace osUtils {
-
-Thread::Thread() :
-    m_thread(NULL),
-    m_threadId(0),
-    m_isRunning(false)
-{
-}
-
-Thread::~Thread()
-{
-    if(m_thread) {
-        CloseHandle(m_thread);
-    }
-}
-
-bool
-Thread::start()
-{
-    m_isRunning = true;
-    m_thread = CreateThread(NULL, 0, &Thread::thread_main, this, 0, &m_threadId);
-    if(!m_thread) {
-        m_isRunning = false;
-    }
-    return m_isRunning;
-}
-
-bool
-Thread::wait(int *exitStatus)
-{
-    if (!m_isRunning) {
-        return false;
-    }
-
-    if(WaitForSingleObject(m_thread, INFINITE) == WAIT_FAILED) {
-        return false;
-    }
-
-    DWORD retval;
-    if (!GetExitCodeThread(m_thread,&retval)) {
-        return false;
-    }
-
-    m_isRunning = 0;
-
-    if (exitStatus) {
-        *exitStatus = retval;
-    }
-    return true;
-}
-
-bool
-Thread::trywait(int *exitStatus)
-{
-    if (!m_isRunning) {
-        return false;
-    }
-
-    if(WaitForSingleObject(m_thread, 0) == WAIT_OBJECT_0) {
-
-        DWORD retval;
-        if (!GetExitCodeThread(m_thread,&retval)) {
-            return true;
-        }
-
-        if (exitStatus) {
-            *exitStatus = retval;
-        }
-        return true;
-    }
-
-    return false;
-}
-
-DWORD WINAPI
-Thread::thread_main(void *p_arg)
-{
-    Thread *self = (Thread *)p_arg;
-    int ret = self->Main();
-    self->m_isRunning = false;
-    ::emugl::ThreadStore::OnThreadExit();
-    return ret;
-}
-
-} // of namespace osUtils
diff --git a/emulator/opengl/shared/emugl/common/Android.mk b/emulator/opengl/shared/emugl/common/Android.mk
index e75f887..fb9ab57 100644
--- a/emulator/opengl/shared/emugl/common/Android.mk
+++ b/emulator/opengl/shared/emugl/common/Android.mk
@@ -17,8 +17,12 @@ commonSources := \
 host_commonSources := $(commonSources)
 
 host_commonLdLibs := -lstdc++
+
 ifneq (windows,$(HOST_OS))
-    host_commonLdLibs += -ldl
+    host_commonSources += thread_pthread.cpp
+    host_commonLdLibs += -ldl -lpthread
+else
+    host_commonSources += thread_win32.cpp
 endif
 
 $(call emugl-begin-host-static-library,libemugl_common)
@@ -47,6 +51,7 @@ host_commonSources := \
     shared_library_unittest.cpp \
     smart_ptr_unittest.cpp \
     thread_store_unittest.cpp \
+    thread_unittest.cpp \
 
 $(call emugl-begin-host-executable,emugl_common_host_unittests)
 LOCAL_SRC_FILES := $(host_commonSources)
diff --git a/emulator/opengl/shared/emugl/common/thread.h b/emulator/opengl/shared/emugl/common/thread.h
new file mode 100644
index 0000000..d0f7d20
--- /dev/null
+++ b/emulator/opengl/shared/emugl/common/thread.h
@@ -0,0 +1,102 @@
+// Copyright (C) 2014 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 EMUGL_COMMON_THREAD_H
+#define EMUGL_COMMON_THREAD_H
+
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <pthread.h>
+#endif
+
+#include <stdint.h>
+
+namespace emugl {
+
+// Wrapper class for platform-specific threads.
+// To create your own thread, define a sub-class of emugl::Thread
+// and override its main() method.
+//
+// For example:
+//
+//    class MyThread : public emugl::Thread {
+//    public:
+//        MyThread() : Thread() {}
+//
+//        virtual intptr_t main() {
+//            ... main thread loop implementation
+//            return 0;
+//        }
+//    };
+//
+//    ...
+//
+//    // Create new instance, but does not start it.
+//    MyThread* thread = new MyThread();
+//
+//    // Start the thread.
+//    thread->start();
+//
+//    // Wait for thread completion, and gets result into |exitStatus|.
+//    int exitStatus;
+//    thread->wait(&exitStatus);
+//
+class Thread {
+public:
+    // Public constructor.
+    Thread();
+
+    // Virtual destructor.
+    virtual ~Thread();
+
+    // Override this method in your own thread sub-classes. This will
+    // be called when start() is invoked on the Thread instance.
+    virtual intptr_t main() = 0;
+
+    // Start a thread instance. Return true on success, false otherwise
+    // (e.g. if the thread was already started or terminated).
+    bool start();
+
+    // Wait for thread termination and retrieve exist status into
+    // |*exitStatus|. Return true on success, false otherwise.
+    // NOTE: |exitStatus| can be NULL.
+    bool  wait(intptr_t *exitStatus);
+
+    // Check whether a thread has terminated. On success, return true
+    // and sets |*exitStatus|. On failure, return false.
+    // NOTE: |exitStatus| can be NULL.
+    bool tryWait(intptr_t *exitStatus);
+
+private:
+#ifdef _WIN32
+    static DWORD WINAPI thread_main(void* arg);
+
+    HANDLE mThread;
+    DWORD mThreadId;
+    CRITICAL_SECTION mLock;
+#else // !WIN32
+    static void* thread_main(void* arg);
+
+    pthread_t mThread;
+    pthread_mutex_t mLock;
+#endif
+    intptr_t mExitStatus;
+    bool mIsRunning;
+};
+
+}  // namespace emugl
+
+#endif  // EMUGL_COMMON_THREAD_H
+
diff --git a/emulator/opengl/shared/emugl/common/thread_pthread.cpp b/emulator/opengl/shared/emugl/common/thread_pthread.cpp
new file mode 100644
index 0000000..5dbc3ab
--- /dev/null
+++ b/emulator/opengl/shared/emugl/common/thread_pthread.cpp
@@ -0,0 +1,114 @@
+// Copyright (C) 2014 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.
+
+#include "emugl/common/thread.h"
+
+#include "emugl/common/thread_store.h"
+
+#include <stdio.h>
+
+namespace emugl {
+
+namespace {
+
+class ScopedLocker {
+public:
+    ScopedLocker(pthread_mutex_t* mutex) : mMutex(mutex) {
+        pthread_mutex_lock(mMutex);
+    }
+
+    ~ScopedLocker() {
+        pthread_mutex_unlock(mMutex);
+    }
+private:
+    pthread_mutex_t* mMutex;
+};
+
+}  // namespace
+
+Thread::Thread() :
+    mThread((pthread_t)NULL),
+    mExitStatus(0),
+    mIsRunning(false) {
+    pthread_mutex_init(&mLock, NULL);
+}
+
+Thread::~Thread() {
+    pthread_mutex_destroy(&mLock);
+}
+
+bool Thread::start() {
+    bool ret = true;
+    pthread_mutex_lock(&mLock);
+    mIsRunning = true;
+    if (pthread_create(&mThread, NULL, thread_main, this)) {
+        ret = false;
+        mIsRunning = false;
+    }
+    pthread_mutex_unlock(&mLock);
+    return ret;
+}
+
+bool Thread::wait(intptr_t *exitStatus) {
+    {
+        ScopedLocker locker(&mLock);
+        if (!mIsRunning) {
+            // Thread already stopped.
+            if (exitStatus) {
+                *exitStatus = mExitStatus;
+            }
+            return true;
+        }
+    }
+
+    // NOTE: Do not hold the lock when waiting for the thread to ensure
+    // it can update mIsRunning and mExitStatus properly in thread_main
+    // without blocking.
+    void *retval;
+    if (pthread_join(mThread, &retval)) {
+        return false;
+    }
+    if (exitStatus) {
+        *exitStatus = (intptr_t)retval;
+    }
+    return true;
+}
+
+bool Thread::tryWait(intptr_t *exitStatus) {
+    ScopedLocker locker(&mLock);
+    if (!mIsRunning) {
+        return false;
+    }
+    if (exitStatus) {
+        *exitStatus = mExitStatus;
+    }
+    return true;
+}
+
+// static
+void* Thread::thread_main(void *arg) {
+    Thread* self = reinterpret_cast<Thread*>(arg);
+    intptr_t ret = self->main();
+
+    pthread_mutex_lock(&self->mLock);
+    self->mIsRunning = false;
+    self->mExitStatus = ret;
+    pthread_mutex_unlock(&self->mLock);
+
+    ::emugl::ThreadStore::OnThreadExit();
+
+    return (void*)ret;
+}
+
+}  // namespace emugl
diff --git a/emulator/opengl/shared/emugl/common/thread_unittest.cpp b/emulator/opengl/shared/emugl/common/thread_unittest.cpp
new file mode 100644
index 0000000..db1931f
--- /dev/null
+++ b/emulator/opengl/shared/emugl/common/thread_unittest.cpp
@@ -0,0 +1,109 @@
+// Copyright (C) 2014 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.
+
+#include "emugl/common/thread.h"
+
+#include "emugl/common/mutex.h"
+
+#include <gtest/gtest.h>
+
+namespace emugl {
+
+namespace {
+
+// A simple thread instance that does nothing at all and exits immediately.
+class EmptyThread : public ::emugl::Thread {
+public:
+    intptr_t main() { return 42; }
+};
+
+class CountingThread : public ::emugl::Thread {
+public:
+    class State {
+    public:
+        State() : mLock(), mCount(0) {}
+        ~State() {}
+
+        void increment() {
+            mLock.lock();
+            mCount++;
+            mLock.unlock();
+        }
+
+        int count() const {
+            int ret;
+            mLock.lock();
+            ret = mCount;
+            mLock.unlock();
+            return ret;
+        }
+
+    private:
+        mutable Mutex mLock;
+        int mCount;
+    };
+
+    CountingThread(State* state) : mState(state) {}
+
+    intptr_t main() {
+        mState->increment();
+        return 0;
+    }
+
+private:
+    State* mState;
+};
+
+}  // namespace
+
+TEST(ThreadTest, SimpleThread) {
+    Thread* thread = new EmptyThread();
+    EXPECT_TRUE(thread);
+    EXPECT_TRUE(thread->start());
+    intptr_t status;
+    EXPECT_TRUE(thread->wait(&status));
+    EXPECT_EQ(42, status);
+}
+
+TEST(ThreadTest, MultipleThreads) {
+    CountingThread::State state;
+    const size_t kMaxThreads = 100;
+    Thread* threads[kMaxThreads];
+
+    // Create all threads.
+    for (size_t n = 0; n < kMaxThreads; ++n) {
+        threads[n] = new CountingThread(&state);
+        EXPECT_TRUE(threads[n]) << "thread " << n;
+    }
+
+    // Start them all.
+    for (size_t n = 0; n < kMaxThreads; ++n) {
+        EXPECT_TRUE(threads[n]->start()) << "thread " << n;
+    }
+
+    // Wait for them all.
+    for (size_t n = 0; n < kMaxThreads; ++n) {
+        EXPECT_TRUE(threads[n]->wait(NULL)) << "thread " << n;
+    }
+
+    // Check state.
+    EXPECT_EQ((int)kMaxThreads, state.count());
+
+    // Delete them all.
+    for (size_t n = 0; n < kMaxThreads; ++n) {
+        delete threads[n];
+    }
+}
+
+}  // namespace emugl
diff --git a/emulator/opengl/shared/emugl/common/thread_win32.cpp b/emulator/opengl/shared/emugl/common/thread_win32.cpp
new file mode 100644
index 0000000..f348ca8
--- /dev/null
+++ b/emulator/opengl/shared/emugl/common/thread_win32.cpp
@@ -0,0 +1,122 @@
+// Copyright (C) 2014 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.
+
+#include "emugl/common/thread.h"
+
+#include "emugl/common/thread_store.h"
+
+namespace emugl {
+
+namespace {
+
+class ScopedLocker {
+public:
+    ScopedLocker(CRITICAL_SECTION* section) : mSection(section) {
+        EnterCriticalSection(mSection);
+    }
+
+    ~ScopedLocker() {
+        LeaveCriticalSection(mSection);
+    }
+private:
+    CRITICAL_SECTION* mSection;
+};
+
+}  // namespace
+
+Thread::Thread() :
+    mThread(INVALID_HANDLE_VALUE),
+    mThreadId(0),
+    mExitStatus(0),
+    mIsRunning(false) {
+    InitializeCriticalSection(&mLock);
+}
+
+Thread::~Thread() {
+    if(mThread != INVALID_HANDLE_VALUE) {
+        CloseHandle(mThread);
+    }
+    DeleteCriticalSection(&mLock);
+}
+
+bool Thread::start() {
+    ScopedLocker locker(&mLock);
+
+    bool ret = true;
+    mIsRunning = true;
+    mThread = CreateThread(NULL, 0, &Thread::thread_main, this, 0, &mThreadId);
+    if (!mThread) {
+        ret = false;
+        mIsRunning = false;
+    }
+    return ret;
+}
+
+bool Thread::wait(intptr_t* exitStatus) {
+    {
+        ScopedLocker locker(&mLock);
+        if (!mIsRunning) {
+            // Thread already stopped.
+            if (exitStatus) {
+                *exitStatus = mExitStatus;
+            }
+            return true;
+        }
+    }
+
+    // NOTE: Do not hold lock during wait to aloow thread_main to
+    // properly update mIsRunning and mExitStatus on thread exit.
+    if (WaitForSingleObject(mThread, INFINITE) == WAIT_FAILED) {
+        return false;
+    }
+
+    if (exitStatus) {
+        ScopedLocker locker(&mLock);
+        *exitStatus = mExitStatus;
+    }
+    return true;
+}
+
+bool Thread::tryWait(intptr_t* exitStatus) {
+    ScopedLocker locker(&mLock);
+
+    if (!mIsRunning ||
+        WaitForSingleObject(mThread, 0) != WAIT_OBJECT_0) {
+        return false;
+    }
+
+    if (exitStatus) {
+        *exitStatus = mExitStatus;
+    }
+    return true;
+}
+
+// static
+DWORD WINAPI Thread::thread_main(void *arg)
+{
+    Thread* self = reinterpret_cast<Thread*>(arg);
+    intptr_t ret = self->main();
+
+    EnterCriticalSection(&self->mLock);
+    self->mIsRunning = false;
+    self->mExitStatus = ret;
+    LeaveCriticalSection(&self->mLock);
+
+    // Ensure all thread-local values are released for this thread.
+    ::emugl::ThreadStore::OnThreadExit();
+
+    return static_cast<DWORD>(ret);
+}
+
+}  // namespace emugl