Set up shell to use for unit tests

Sets up a unit test file that can be used to unit test the HalProxy. The
unit tests will eventually end up containing code that injects the fake
SensorsSubHal implementation into the HalProxy and verifies various
parts of the implementation. This will likely require some modifications
to the SensorsSubHal class to modify it during test execution, but it's
better that the same implementation is shared between unit / manual
integration testing.

Test: Run atest android.hardware.sensors@2.0-halproxy-unit-tests
Bug: 136511617
Change-Id: I7b6865564ea41ab3c58f77d3168366c95e3289e5
diff --git a/sensors/2.0/multihal/include/HalProxy.h b/sensors/2.0/multihal/include/HalProxy.h
new file mode 100644
index 0000000..9d5787c
--- /dev/null
+++ b/sensors/2.0/multihal/include/HalProxy.h
@@ -0,0 +1,127 @@
+/*
+ * 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 "SubHal.h"
+
+#include <android/hardware/sensors/2.0/ISensors.h>
+#include <fmq/MessageQueue.h>
+#include <hardware_legacy/power.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+
+namespace android {
+namespace hardware {
+namespace sensors {
+namespace V2_0 {
+namespace implementation {
+
+using ::android::sp;
+using ::android::hardware::EventFlag;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::MessageQueue;
+using ::android::hardware::MQDescriptor;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+
+struct HalProxy : public ISensors {
+    using Event = ::android::hardware::sensors::V1_0::Event;
+    using OperationMode = ::android::hardware::sensors::V1_0::OperationMode;
+    using RateLevel = ::android::hardware::sensors::V1_0::RateLevel;
+    using Result = ::android::hardware::sensors::V1_0::Result;
+    using SharedMemInfo = ::android::hardware::sensors::V1_0::SharedMemInfo;
+
+    explicit HalProxy();
+    // Test only constructor.
+    explicit HalProxy(std::vector<ISensorsSubHal*>& subHalList);
+    ~HalProxy();
+
+    // Methods from ::android::hardware::sensors::V2_0::ISensors follow.
+    Return<void> getSensorsList(getSensorsList_cb _hidl_cb) override;
+
+    Return<Result> setOperationMode(OperationMode mode) override;
+
+    Return<Result> activate(int32_t sensorHandle, bool enabled) override;
+
+    Return<Result> initialize(
+            const ::android::hardware::MQDescriptorSync<Event>& eventQueueDescriptor,
+            const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
+            const sp<ISensorsCallback>& sensorsCallback) override;
+
+    Return<Result> batch(int32_t sensorHandle, int64_t samplingPeriodNs,
+                         int64_t maxReportLatencyNs) override;
+
+    Return<Result> flush(int32_t sensorHandle) override;
+
+    Return<Result> injectSensorData(const Event& event) override;
+
+    Return<void> registerDirectChannel(const SharedMemInfo& mem,
+                                       registerDirectChannel_cb _hidl_cb) override;
+
+    Return<Result> unregisterDirectChannel(int32_t channelHandle) override;
+
+    Return<void> configDirectReport(int32_t sensorHandle, int32_t channelHandle, RateLevel rate,
+                                    configDirectReport_cb _hidl_cb) override;
+
+    Return<void> debug(const hidl_handle& fd, const hidl_vec<hidl_string>& args) override;
+
+    // Below methods from ::android::hardware::sensors::V2_0::ISensorsCallback with a minor change
+    // to pass in the sub-HAL index. While the above methods are invoked from the sensors framework
+    // via the binder, these methods are invoked from a callback provided to sub-HALs inside the
+    // same process as the HalProxy, but potentially running on different threads.
+    Return<void> onDynamicSensorsConnected(const hidl_vec<SensorInfo>& dynamicSensorsAdded,
+                                           int32_t subHalIndex);
+
+    Return<void> onDynamicSensorsDisconnected(const hidl_vec<int32_t>& dynamicSensorHandlesRemoved,
+                                              int32_t subHalIndex);
+
+  private:
+    using EventMessageQueue = MessageQueue<Event, kSynchronizedReadWrite>;
+    using WakeLockMessageQueue = MessageQueue<uint32_t, kSynchronizedReadWrite>;
+
+    /**
+     * The Event FMQ where sensor events are written
+     */
+    std::unique_ptr<EventMessageQueue> mEventQueue;
+
+    /**
+     * The Wake Lock FMQ that is read to determine when the framework has handled WAKE_UP events
+     */
+    std::unique_ptr<WakeLockMessageQueue> mWakeLockQueue;
+
+    /**
+     * Event Flag to signal to the framework when sensor events are available to be read
+     */
+    EventFlag* mEventQueueFlag;
+
+    /**
+     * Callback to the sensors framework to inform it that new sensors have been added or removed.
+     */
+    sp<ISensorsCallback> mDynamicSensorsCallback;
+
+    /**
+     * SubHal object pointers that have been saved from vendor dynamic libraries.
+     */
+    std::vector<ISensorsSubHal*> mSubHalList;
+};
+
+}  // namespace implementation
+}  // namespace V2_0
+}  // namespace sensors
+}  // namespace hardware
+}  // namespace android