Default hal for Occupant Awareness.

Bug: 142383127
Test: Verified that the system starts the default hal automatically.
Change-Id: I851f85bc283165891943b82c6c07f3273847b032
diff --git a/automotive/occupant_awareness/aidl/default/OccupantAwareness.h b/automotive/occupant_awareness/aidl/default/OccupantAwareness.h
new file mode 100644
index 0000000..ac51aa4
--- /dev/null
+++ b/automotive/occupant_awareness/aidl/default/OccupantAwareness.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#pragma once
+#include <aidl/android/hardware/automotive/occupant_awareness/BnOccupantAwareness.h>
+#include <aidl/android/hardware/automotive/occupant_awareness/BnOccupantAwarenessClientCallback.h>
+#include <utils/StrongPointer.h>
+
+namespace android {
+namespace hardware {
+namespace automotive {
+namespace occupant_awareness {
+namespace V1_0 {
+namespace implementation {
+
+using ::aidl::android::hardware::automotive::occupant_awareness::BnOccupantAwareness;
+using ::aidl::android::hardware::automotive::occupant_awareness::IOccupantAwarenessClientCallback;
+using ::aidl::android::hardware::automotive::occupant_awareness::OccupantAwarenessStatus;
+using ::aidl::android::hardware::automotive::occupant_awareness::OccupantDetections;
+using ::aidl::android::hardware::automotive::occupant_awareness::Role;
+
+/**
+ * The default HAL mimics a system which has no Occupant awareness capability. The hal does not
+ * do any useful work, and returns appropriate failure code / status.
+ **/
+class OccupantAwareness : public BnOccupantAwareness {
+  public:
+    // Methods from ::android::hardware::automotive::occupant_awareness::IOccupantAwareness
+    // follow.
+    ndk::ScopedAStatus startDetection(OccupantAwarenessStatus* status) override;
+    ndk::ScopedAStatus stopDetection(OccupantAwarenessStatus* status) override;
+    ndk::ScopedAStatus getCapabilityForRole(Role occupantRole, int32_t* capabilities) override;
+    ndk::ScopedAStatus getState(Role occupantRole, int detectionCapability,
+                                OccupantAwarenessStatus* status) override;
+    ndk::ScopedAStatus setCallback(
+            const std::shared_ptr<IOccupantAwarenessClientCallback>& callback) override;
+    ndk::ScopedAStatus getLatestDetection(OccupantDetections* detections) override;
+
+  private:
+    bool isValidRole(Role occupantRole);
+    bool isValidDetectionCapabilities(int detectionCapabilities);
+    bool isSingularCapability(int detectionCapability);
+
+    std::mutex mMutex;
+    std::shared_ptr<IOccupantAwarenessClientCallback> mCallback = nullptr;
+    OccupantAwarenessStatus mStatus = OccupantAwarenessStatus::NOT_INITIALIZED;
+};
+
+}  // namespace implementation
+}  // namespace V1_0
+}  // namespace occupant_awareness
+}  // namespace automotive
+}  // namespace hardware
+}  // namespace android