--- /dev/null
+// 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 <assert.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),
+ mLock(),
+ mJoined(false),
+ mExitStatus(0),
+ mIsRunning(false) {
+ pthread_mutex_init(&mLock, NULL);
+}
+
+Thread::~Thread() {
+ assert(!mIsRunning);
+ assert(mJoined);
+ 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;
+ }
+ if (!mJoined) {
+ // reclaim thread stack
+ pthread_join(mThread, NULL);
+ mJoined = true;
+ }
+ 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;
+ }
+ // Note: Updating mJoined must be performed inside the lock to avoid
+ // race conditions between two threads waiting for the same thread
+ // that just completed its execution.
+ {
+ ScopedLocker locker(&mLock);
+ mJoined = true;
+ }
+ return true;
+}
+
+bool Thread::tryWait(intptr_t *exitStatus) {
+ ScopedLocker locker(&mLock);
+ if (mIsRunning) {
+ return false;
+ }
+ if (!mJoined) {
+ // Reclaim stack.
+ pthread_join(mThread, NULL);
+ mJoined = true;
+ }
+ 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