[sensors] Generic Sensors Framework blink side

third_party/WebKit/Source/modules/sensor/SensorProxy.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SensorProxy_h
+#define SensorProxy_h
+
+#include "device/generic_sensor/public/interfaces/sensor.mojom-blink.h"
+#include "device/generic_sensor/public/interfaces/sensor_provider.mojom-blink.h"
+#include "mojo/public/cpp/bindings/binding.h"
+#include "platform/Supplementable.h"
+#include "platform/heap/Handle.h"
+
+namespace blink {
+
+class SensorProviderProxy;
+
+// This class wraps 'Sensor' mojo interface and used by multiple
+// JS sensor instances of the same type (within a single frame).
+class SensorProxy final
+    : public GarbageCollectedFinalized<SensorProxy>
+    , public device::mojom::blink::SensorClient {
+    USING_PRE_FINALIZER(SensorProxy, dispose);
+    WTF_MAKE_NONCOPYABLE(SensorProxy);
+public:
+    class Observer : public GarbageCollectedMixin {
+    public:
+        // Has valid 'Sensor' binding, {add, remove}Configuration()
+        // methods can be called.
+        virtual void onSensorInitialized() {}
+        // Platfrom sensort reading has changed (for 'ONCHANGE' reporting mode).
+        virtual void onSensorReadingChanged() {}
+        // An error has occurred.
+        virtual void onSensorError() {}
+    };
+
+    ~SensorProxy();
+
+    void dispose();
+
+    void addObserver(Observer*);
+    void removeObserver(Observer*);
+
+    void initialize();
+
+    bool isInitializing() const { return m_state == Initializing; }
+    bool isInitialized() const { return m_state == Initialized; }
+
+    void addConfiguration(device::mojom::blink::SensorConfigurationPtr, std::unique_ptr<Function<void(bool)>>);
+    void removeConfiguration(device::mojom::blink::SensorConfigurationPtr, std::unique_ptr<Function<void(bool)>>);
+
+    device::mojom::blink::SensorType type() const { return m_type; }
+    device::mojom::blink::ReportingMode reportingMode() const { return m_mode; }
+
+    struct Reading {
+        double timestamp;
+        double reading[3];
+    };
+    static_assert(sizeof(Reading) == device::mojom::blink::SensorReadBuffer::kReadBufferSize, "Check reading size");
+
+    const Reading& reading() const { return m_reading; }
+
+    // Updates internal reading from shared buffer.
+    void updateInternalReading();
+
+    DECLARE_VIRTUAL_TRACE();
+
+private:
+    friend class SensorProviderProxy;
+    SensorProxy(device::mojom::blink::SensorType, SensorProviderProxy*);
+
+    // device::mojom::blink::SensorClient overrides.
+    void RaiseError() override;
+    void SensorReadingChanged() override;
+
+    // Generic handler for a fatal error.
+    void handleSensorError();
+
+    void onSensorCreated(device::mojom::blink::SensorReadBufferPtr, device::mojom::blink::SensorClientRequest);
+
+    device::mojom::blink::SensorType m_type;
+    device::mojom::blink::ReportingMode m_mode;
+    Member<SensorProviderProxy> m_provider;
+    using ObserversSet = HeapHashSet<WeakMember<Observer>>;
+    ObserversSet m_observers;
+
+    device::mojom::blink::SensorPtr m_sensor;
+    mojo::Binding<device::mojom::blink::SensorClient> m_clientBinding;
+    enum State {
+        Uninitialized,
+        Initializing,
+        Initialized
+    };
+    State m_state;
+    mojo::ScopedSharedBufferHandle m_sharedBufferHandle;
+    mojo::ScopedSharedBufferMapping m_sharedBuffer;
+    Reading m_reading;
+};
+
+} // namespace blink
+
+#endif // SensorProxy_h