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diff --git a/services/camera/libcameraservice/utils/AutoConditionLock.h b/services/camera/libcameraservice/utils/AutoConditionLock.h
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+/*
+ * Copyright (C) 2015 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 ANDROID_SERVICE_UTILS_SCOPED_CONDITION_H
+#define ANDROID_SERVICE_UTILS_SCOPED_CONDITION_H
+
+#include <utils/Timers.h>
+#include <utils/Condition.h>
+#include <utils/Errors.h>
+#include <utils/Mutex.h>
+
+#include <memory>
+
+namespace android {
+
+/**
+ * WaitableMutexWrapper can be used with AutoConditionLock to construct scoped locks for the
+ * wrapped Mutex with timeouts for lock acquisition.
+ */
+class WaitableMutexWrapper {
+    friend class AutoConditionLock;
+public:
+    /**
+     * Construct the ConditionManger with the given Mutex.
+     */
+    WaitableMutexWrapper(Mutex* mutex);
+
+    virtual ~WaitableMutexWrapper();
+private:
+    Mutex* mMutex;
+    bool mState;
+    Condition mCondition;
+};
+
+/**
+ * AutoConditionLock is a scoped lock similar to Mutex::Autolock, but allows timeouts to be
+ * specified for lock acquisition.
+ *
+ * AutoConditionLock is used with a WaitableMutexWrapper to lock/unlock the WaitableMutexWrapper's
+ * wrapped Mutex, and wait/set/signal the WaitableMutexWrapper's wrapped condition. To use this,
+ * call AutoConditionLock::waitAndAcquire to get an instance.  This will:
+ *      - Lock the given WaitableMutexWrapper's mutex.
+ *      - Wait for the WaitableMutexWrapper's condition to become false, or timeout.
+ *      - Set the WaitableMutexWrapper's condition to true.
+ *
+ * When the AutoConditionLock goes out of scope and is destroyed, this will:
+ *      - Set the WaitableMutexWrapper's condition to false.
+ *      - Signal threads waiting on this condition to wakeup.
+ *      - Release WaitableMutexWrapper's mutex.
+ */
+class AutoConditionLock final {
+public:
+    AutoConditionLock() = delete;
+    AutoConditionLock(const AutoConditionLock& other) = delete;
+    AutoConditionLock & operator=(const AutoConditionLock&) = delete;
+
+    ~AutoConditionLock();
+
+    /**
+     * Make a new AutoConditionLock from a given WaitableMutexWrapper, waiting up to waitTime
+     * nanoseconds to acquire the WaitableMutexWrapper's wrapped lock.
+     *
+     * Return an empty unique_ptr if this fails, or a timeout occurs.
+     */
+    static std::unique_ptr<AutoConditionLock> waitAndAcquire(
+            const std::shared_ptr<WaitableMutexWrapper>& manager, nsecs_t waitTime);
+
+    /**
+     * Make a new AutoConditionLock from a given WaitableMutexWrapper, waiting indefinitely to
+     * acquire the WaitableMutexWrapper's wrapped lock.
+     *
+     * Return an empty unique_ptr if this fails.
+     */
+    static std::unique_ptr<AutoConditionLock> waitAndAcquire(
+            const std::shared_ptr<WaitableMutexWrapper>& manager);
+private:
+    AutoConditionLock(const std::shared_ptr<WaitableMutexWrapper>& manager);
+
+    std::shared_ptr<WaitableMutexWrapper> mManager;
+    Mutex::Autolock mAutoLock;
+};
+
+}; // namespace android
+
+#endif // ANDROID_SERVICE_UTILS_SCOPED_CONDITION_H