Add computepipe example implementation

Fix: 148017613

Change-Id: I0b579cd5ce45deff0e723634fdf4a09513715e83
diff --git a/computepipe/example/FaceTracker.h b/computepipe/example/FaceTracker.h
new file mode 100644
index 0000000..ea6ba8b
--- /dev/null
+++ b/computepipe/example/FaceTracker.h
@@ -0,0 +1,106 @@
+// Copyright 2020 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 COMPUTEPIPE_EXAMPLE_FACE_TRACKER_H
+#define COMPUTEPIPE_EXAMPLE_FACE_TRACKER_H
+
+#include <aidl/android/automotive/computepipe/registry/BnClientInfo.h>
+#include <aidl/android/automotive/computepipe/registry/IPipeQuery.h>
+#include <aidl/android/automotive/computepipe/registry/IPipeRegistration.h>
+#include <aidl/android/automotive/computepipe/runner/BnPipeStateCallback.h>
+#include <aidl/android/automotive/computepipe/runner/BnPipeStream.h>
+#include <aidl/android/automotive/computepipe/runner/PipeState.h>
+
+#include <condition_variable>
+#include <iostream>
+#include <memory>
+
+#include "FaceOutput.pb.h"
+
+namespace android {
+namespace automotive {
+namespace computepipe {
+
+using ::aidl::android::automotive::computepipe::registry::BnClientInfo;
+using ::aidl::android::automotive::computepipe::registry::IPipeQuery;
+using ::aidl::android::automotive::computepipe::runner::BnPipeStateCallback;
+using ::aidl::android::automotive::computepipe::runner::BnPipeStream;
+using ::aidl::android::automotive::computepipe::runner::IPipeRunner;
+using ::aidl::android::automotive::computepipe::runner::IPipeStream;
+using ::aidl::android::automotive::computepipe::runner::PacketDescriptor;
+using ::aidl::android::automotive::computepipe::runner::PipeState;
+using ::android::automotive::computepipe::example::BoundingBox;
+
+class RemoteState {
+  public:
+    explicit RemoteState(std::function<void(bool, std::string)>& cb);
+    PipeState GetCurrentState();
+    void UpdateCurrentState(const PipeState& state);
+
+  private:
+    bool hasChanged = false;
+    PipeState mState = PipeState::RESET;
+    std::mutex mStateLock;
+    std::condition_variable mWait;
+    std::function<void(bool, std::string)> mTerminationCb;
+};
+
+class ClientInfo : public BnClientInfo {
+  public:
+    ndk::ScopedAStatus getClientId(int32_t* _aidl_return) {
+        if (_aidl_return) {
+            *_aidl_return = 0;
+            return ndk::ScopedAStatus::ok();
+        }
+        return ndk::ScopedAStatus::fromExceptionCode(EX_TRANSACTION_FAILED);
+    }
+};
+
+class StreamCallback : public BnPipeStream {
+  public:
+    StreamCallback() = default;
+    ndk::ScopedAStatus deliverPacket(const PacketDescriptor& in_packet) override;
+
+  private:
+    BoundingBox mLastBox;
+};
+
+class StateCallback : public BnPipeStateCallback {
+  public:
+    explicit StateCallback(std::shared_ptr<RemoteState> s);
+    ndk::ScopedAStatus handleState(PipeState state) override;
+
+  private:
+    std::shared_ptr<RemoteState> mStateTracker = nullptr;
+};
+
+class FaceTracker {
+  public:
+    FaceTracker() = default;
+    ndk::ScopedAStatus init(std::function<void(bool, std::string)>&& termination);
+    void start();
+    void stop();
+
+  private:
+    ndk::ScopedAStatus setupConfig();
+    std::shared_ptr<IPipeRunner> mPipeRunner = nullptr;
+    std::shared_ptr<ClientInfo> mClientInfo = nullptr;
+    std::shared_ptr<StreamCallback> mStreamCallback = nullptr;
+    std::shared_ptr<StateCallback> mStateCallback = nullptr;
+    std::shared_ptr<RemoteState> mRemoteState = nullptr;
+};
+
+}  // namespace computepipe
+}  // namespace automotive
+}  // namespace android
+#endif