SF: HWC2 C++ shim

Provides an object-based C++ interface to the HWC 2.0 HAL

Change-Id: Ie1a7bfd2f6faa548bc45da845a4f50f1915b5806
diff --git a/services/surfaceflinger/DisplayHardware/HWC2.h b/services/surfaceflinger/DisplayHardware/HWC2.h
new file mode 100644
index 0000000..a7bd28c
--- /dev/null
+++ b/services/surfaceflinger/DisplayHardware/HWC2.h
@@ -0,0 +1,377 @@
+/*
+ * Copyright 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_SF_HWC2_H
+#define ANDROID_SF_HWC2_H
+
+#define HWC2_INCLUDE_STRINGIFICATION
+#define HWC2_USE_CPP11
+#include <hardware/hwcomposer2.h>
+#undef HWC2_INCLUDE_STRINGIFICATION
+#undef HWC2_USE_CPP11
+
+#include <utils/Log.h>
+#include <utils/StrongPointer.h>
+#include <utils/Timers.h>
+
+#include <functional>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+namespace android {
+    class Fence;
+    class FloatRect;
+    class GraphicBuffer;
+    class Rect;
+    class Region;
+}
+
+namespace HWC2 {
+
+class Display;
+class Layer;
+
+typedef std::function<void(std::shared_ptr<Display>, Connection)>
+        HotplugCallback;
+typedef std::function<void(std::shared_ptr<Display>)> RefreshCallback;
+typedef std::function<void(std::shared_ptr<Display>, nsecs_t)> VsyncCallback;
+
+class Device
+{
+public:
+    Device(hwc2_device_t* device);
+    ~Device();
+
+    friend class HWC2::Display;
+    friend class HWC2::Layer;
+
+    // Required by HWC2
+
+    std::string dump() const;
+
+    const std::vector<Capability>& getCapabilities() const {
+        return mCapabilities;
+    };
+
+    uint32_t getMaxVirtualDisplayCount() const;
+    Error createVirtualDisplay(uint32_t width, uint32_t height,
+            std::shared_ptr<Display>* outDisplay);
+
+    void registerHotplugCallback(HotplugCallback hotplug);
+    void registerRefreshCallback(RefreshCallback refresh);
+    void registerVsyncCallback(VsyncCallback vsync);
+
+    // For use by callbacks
+
+    void callHotplug(std::shared_ptr<Display> display, Connection connected);
+    void callRefresh(std::shared_ptr<Display> display);
+    void callVsync(std::shared_ptr<Display> display, nsecs_t timestamp);
+
+    // Other Device methods
+
+    // This will create a Display if one is not found, but it will not be marked
+    // as connected
+    std::shared_ptr<Display> getDisplayById(hwc2_display_t id);
+
+private:
+    // Initialization methods
+
+    template <typename PFN>
+    [[clang::warn_unused_result]] bool loadFunctionPointer(
+            FunctionDescriptor desc, PFN& outPFN) {
+        auto intDesc = static_cast<int32_t>(desc);
+        auto pfn = mHwcDevice->getFunction(mHwcDevice, intDesc);
+        if (pfn != nullptr) {
+            outPFN = reinterpret_cast<PFN>(pfn);
+            return true;
+        } else {
+            ALOGE("Failed to load function %s", to_string(desc).c_str());
+            return false;
+        }
+    }
+
+    template <typename PFN, typename HOOK>
+    void registerCallback(Callback callback, HOOK hook) {
+        static_assert(std::is_same<PFN, HOOK>::value,
+                "Incompatible function pointer");
+        auto intCallback = static_cast<int32_t>(callback);
+        auto callbackData = static_cast<hwc2_callback_data_t>(this);
+        auto pfn = reinterpret_cast<hwc2_function_pointer_t>(hook);
+        mRegisterCallback(mHwcDevice, intCallback, callbackData, pfn);
+    }
+
+    void loadCapabilities();
+    void loadFunctionPointers();
+    void registerCallbacks();
+
+    // For use by Display
+
+    void destroyVirtualDisplay(hwc2_display_t display);
+
+    // Member variables
+
+    hwc2_device_t* mHwcDevice;
+
+    // Device function pointers
+    HWC2_PFN_CREATE_VIRTUAL_DISPLAY mCreateVirtualDisplay;
+    HWC2_PFN_DESTROY_VIRTUAL_DISPLAY mDestroyVirtualDisplay;
+    HWC2_PFN_DUMP mDump;
+    HWC2_PFN_GET_MAX_VIRTUAL_DISPLAY_COUNT mGetMaxVirtualDisplayCount;
+    HWC2_PFN_REGISTER_CALLBACK mRegisterCallback;
+
+    // Display function pointers
+    HWC2_PFN_ACCEPT_DISPLAY_CHANGES mAcceptDisplayChanges;
+    HWC2_PFN_CREATE_LAYER mCreateLayer;
+    HWC2_PFN_DESTROY_LAYER mDestroyLayer;
+    HWC2_PFN_GET_ACTIVE_CONFIG mGetActiveConfig;
+    HWC2_PFN_GET_CHANGED_COMPOSITION_TYPES mGetChangedCompositionTypes;
+    HWC2_PFN_GET_DISPLAY_ATTRIBUTE mGetDisplayAttribute;
+    HWC2_PFN_GET_DISPLAY_CONFIGS mGetDisplayConfigs;
+    HWC2_PFN_GET_DISPLAY_NAME mGetDisplayName;
+    HWC2_PFN_GET_DISPLAY_REQUESTS mGetDisplayRequests;
+    HWC2_PFN_GET_DISPLAY_TYPE mGetDisplayType;
+    HWC2_PFN_GET_DOZE_SUPPORT mGetDozeSupport;
+    HWC2_PFN_GET_RELEASE_FENCES mGetReleaseFences;
+    HWC2_PFN_PRESENT_DISPLAY mPresentDisplay;
+    HWC2_PFN_SET_ACTIVE_CONFIG mSetActiveConfig;
+    HWC2_PFN_SET_CLIENT_TARGET mSetClientTarget;
+    HWC2_PFN_SET_OUTPUT_BUFFER mSetOutputBuffer;
+    HWC2_PFN_SET_POWER_MODE mSetPowerMode;
+    HWC2_PFN_SET_VSYNC_ENABLED mSetVsyncEnabled;
+    HWC2_PFN_VALIDATE_DISPLAY mValidateDisplay;
+
+    // Layer function pointers
+    HWC2_PFN_SET_CURSOR_POSITION mSetCursorPosition;
+    HWC2_PFN_SET_LAYER_BUFFER mSetLayerBuffer;
+    HWC2_PFN_SET_LAYER_SURFACE_DAMAGE mSetLayerSurfaceDamage;
+    HWC2_PFN_SET_LAYER_BLEND_MODE mSetLayerBlendMode;
+    HWC2_PFN_SET_LAYER_COLOR mSetLayerColor;
+    HWC2_PFN_SET_LAYER_COMPOSITION_TYPE mSetLayerCompositionType;
+    HWC2_PFN_SET_LAYER_DISPLAY_FRAME mSetLayerDisplayFrame;
+    HWC2_PFN_SET_LAYER_PLANE_ALPHA mSetLayerPlaneAlpha;
+    HWC2_PFN_SET_LAYER_SIDEBAND_STREAM mSetLayerSidebandStream;
+    HWC2_PFN_SET_LAYER_SOURCE_CROP mSetLayerSourceCrop;
+    HWC2_PFN_SET_LAYER_TRANSFORM mSetLayerTransform;
+    HWC2_PFN_SET_LAYER_VISIBLE_REGION mSetLayerVisibleRegion;
+    HWC2_PFN_SET_LAYER_Z_ORDER mSetLayerZOrder;
+
+    std::vector<Capability> mCapabilities;
+    std::unordered_map<hwc2_display_t, std::shared_ptr<Display>> mDisplays;
+
+    HotplugCallback mHotplug;
+    std::vector<std::pair<std::shared_ptr<Display>, Connection>>
+            mPendingHotplugs;
+    RefreshCallback mRefresh;
+    std::vector<std::shared_ptr<Display>> mPendingRefreshes;
+    VsyncCallback mVsync;
+    std::vector<std::pair<std::shared_ptr<Display>, nsecs_t>> mPendingVsyncs;
+};
+
+class Display : public std::enable_shared_from_this<Display>
+{
+public:
+    Display(Device& device, hwc2_display_t id);
+    ~Display();
+
+    friend class HWC2::Device;
+    friend class HWC2::Layer;
+
+    class Config
+    {
+    public:
+        class Builder
+        {
+        public:
+            Builder(Display& display, hwc2_config_t id);
+
+            std::shared_ptr<const Config> build() {
+                return std::const_pointer_cast<const Config>(
+                        std::move(mConfig));
+            }
+
+            Builder& setWidth(int32_t width) {
+                mConfig->mWidth = width;
+                return *this;
+            }
+            Builder& setHeight(int32_t height) {
+                mConfig->mHeight = height;
+                return *this;
+            }
+            Builder& setVsyncPeriod(int32_t vsyncPeriod) {
+                mConfig->mVsyncPeriod = vsyncPeriod;
+                return *this;
+            }
+            Builder& setDpiX(int32_t dpiX) {
+                if (dpiX == -1) {
+                    mConfig->mDpiX = getDefaultDensity();
+                } else {
+                    mConfig->mDpiX = dpiX / 1000.0f;
+                }
+                return *this;
+            }
+            Builder& setDpiY(int32_t dpiY) {
+                if (dpiY == -1) {
+                    mConfig->mDpiY = getDefaultDensity();
+                } else {
+                    mConfig->mDpiY = dpiY / 1000.0f;
+                }
+                return *this;
+            }
+
+        private:
+            float getDefaultDensity();
+            std::shared_ptr<Config> mConfig;
+        };
+
+        hwc2_display_t getDisplayId() const { return mDisplay.getId(); }
+        hwc2_config_t getId() const { return mId; }
+
+        int32_t getWidth() const { return mWidth; }
+        int32_t getHeight() const { return mHeight; }
+        nsecs_t getVsyncPeriod() const { return mVsyncPeriod; }
+        float getDpiX() const { return mDpiX; }
+        float getDpiY() const { return mDpiY; }
+
+    private:
+        Config(Display& display, hwc2_config_t id);
+
+        Display& mDisplay;
+        hwc2_config_t mId;
+
+        int32_t mWidth;
+        int32_t mHeight;
+        nsecs_t mVsyncPeriod;
+        float mDpiX;
+        float mDpiY;
+    };
+
+    // Required by HWC2
+
+    [[clang::warn_unused_result]] Error acceptChanges();
+    [[clang::warn_unused_result]] Error createLayer(
+            std::shared_ptr<Layer>* outLayer);
+    [[clang::warn_unused_result]] Error getActiveConfig(
+            std::shared_ptr<const Config>* outConfig) const;
+    [[clang::warn_unused_result]] Error getChangedCompositionTypes(
+            std::unordered_map<std::shared_ptr<Layer>, Composition>* outTypes);
+
+    // Doesn't call into the HWC2 device, so no errors are possible
+    std::vector<std::shared_ptr<const Config>> getConfigs() const;
+
+    [[clang::warn_unused_result]] Error getName(std::string* outName) const;
+    [[clang::warn_unused_result]] Error getRequests(
+            DisplayRequest* outDisplayRequests,
+            std::unordered_map<std::shared_ptr<Layer>, LayerRequest>*
+                    outLayerRequests);
+    [[clang::warn_unused_result]] Error getType(DisplayType* outType) const;
+    [[clang::warn_unused_result]] Error supportsDoze(bool* outSupport) const;
+    [[clang::warn_unused_result]] Error getReleaseFences(
+            std::unordered_map<std::shared_ptr<Layer>,
+                    android::sp<android::Fence>>* outFences) const;
+    [[clang::warn_unused_result]] Error present(
+            android::sp<android::Fence>* outRetireFence);
+    [[clang::warn_unused_result]] Error setActiveConfig(
+            const std::shared_ptr<const Config>& config);
+    [[clang::warn_unused_result]] Error setClientTarget(
+            buffer_handle_t target,
+            const android::sp<android::Fence>& acquireFence,
+            android_dataspace_t dataspace);
+    [[clang::warn_unused_result]] Error setOutputBuffer(
+            const android::sp<android::GraphicBuffer>& buffer,
+            const android::sp<android::Fence>& releaseFence);
+    [[clang::warn_unused_result]] Error setPowerMode(PowerMode mode);
+    [[clang::warn_unused_result]] Error setVsyncEnabled(Vsync enabled);
+    [[clang::warn_unused_result]] Error validate(uint32_t* outNumTypes,
+            uint32_t* outNumRequests);
+
+    // Other Display methods
+
+    Device& getDevice() const { return mDevice; }
+    hwc2_display_t getId() const { return mId; }
+    bool isConnected() const { return mIsConnected; }
+
+private:
+    // For use by Device
+
+    // Virtual displays are always connected
+    void setVirtual() {
+        mIsVirtual = true;
+        mIsConnected = true;
+    }
+
+    void setConnected(bool connected) { mIsConnected = connected; }
+    int32_t getAttribute(hwc2_config_t configId, Attribute attribute);
+    void loadConfig(hwc2_config_t configId);
+    void loadConfigs();
+
+    // For use by Layer
+    void destroyLayer(hwc2_layer_t layerId);
+
+    // This may fail (and return a null pointer) if no layer with this ID exists
+    // on this display
+    std::shared_ptr<Layer> getLayerById(hwc2_layer_t id) const;
+
+    // Member variables
+
+    Device& mDevice;
+    hwc2_display_t mId;
+    bool mIsConnected;
+    bool mIsVirtual;
+    std::unordered_map<hwc2_layer_t, std::weak_ptr<Layer>> mLayers;
+    std::unordered_map<hwc2_config_t, std::shared_ptr<const Config>> mConfigs;
+};
+
+class Layer
+{
+public:
+    Layer(const std::shared_ptr<Display>& display, hwc2_layer_t id);
+    ~Layer();
+
+    bool isAbandoned() const { return mDisplay.expired(); }
+    hwc2_layer_t getId() const { return mId; }
+
+    [[clang::warn_unused_result]] Error setCursorPosition(int32_t x, int32_t y);
+    [[clang::warn_unused_result]] Error setBuffer(buffer_handle_t buffer,
+            const android::sp<android::Fence>& acquireFence);
+    [[clang::warn_unused_result]] Error setSurfaceDamage(
+            const android::Region& damage);
+
+    [[clang::warn_unused_result]] Error setBlendMode(BlendMode mode);
+    [[clang::warn_unused_result]] Error setColor(hwc_color_t color);
+    [[clang::warn_unused_result]] Error setCompositionType(Composition type);
+    [[clang::warn_unused_result]] Error setDisplayFrame(
+            const android::Rect& frame);
+    [[clang::warn_unused_result]] Error setPlaneAlpha(float alpha);
+    [[clang::warn_unused_result]] Error setSidebandStream(
+            const native_handle_t* stream);
+    [[clang::warn_unused_result]] Error setSourceCrop(
+            const android::FloatRect& crop);
+    [[clang::warn_unused_result]] Error setTransform(Transform transform);
+    [[clang::warn_unused_result]] Error setVisibleRegion(
+            const android::Region& region);
+    [[clang::warn_unused_result]] Error setZOrder(uint32_t z);
+
+private:
+    std::weak_ptr<Display> mDisplay;
+    hwc2_display_t mDisplayId;
+    Device& mDevice;
+    hwc2_layer_t mId;
+};
+
+} // namespace HWC2
+
+#endif // ANDROID_SF_HWC2_H