path: root/gfx/layers/ipc/CanvasTranslator.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

#ifndef mozilla_layers_CanvasTranslator_h
#define mozilla_layers_CanvasTranslator_h

#include <unordered_map>
#include <vector>

#include "mozilla/dom/ipc/IdType.h"
#include "mozilla/gfx/InlineTranslator.h"
#include "mozilla/gfx/RecordedEvent.h"
#include "CanvasChild.h"
#include "mozilla/layers/CanvasDrawEventRecorder.h"
#include "mozilla/layers/LayersSurfaces.h"
#include "mozilla/layers/PCanvasParent.h"
#include "mozilla/layers/RemoteTextureMap.h"
#include "mozilla/ipc/CrossProcessSemaphore.h"
#include "mozilla/Monitor.h"
#include "mozilla/UniquePtr.h"

namespace mozilla {

using EventType = gfx::RecordedEvent::EventType;
class TaskQueue;

namespace gfx {
class DrawTargetWebgl;
class SharedContextWebgl;
}  // namespace gfx

namespace layers {

class SharedSurfacesHolder;
class TextureData;

class CanvasTranslator final : public gfx::InlineTranslator,
                               public PCanvasParent {
 public:
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(CanvasTranslator)

  friend class PProtocolParent;

  CanvasTranslator(layers::SharedSurfacesHolder* aSharedSurfacesHolder,
                   const dom::ContentParentId& aContentId, uint32_t aManagerId);

  const dom::ContentParentId& GetContentId() const { return mContentId; }

  uint32_t GetManagerId() const { return mManagerId; }

  /**
   * Dispatches a runnable to the preferred task queue or thread.
   *
   * @param aRunnable the runnable to dispatch
   */
  void DispatchToTaskQueue(already_AddRefed<nsIRunnable> aRunnable);

  /**
   * @returns true if running in the preferred task queue or thread for
   * translation.
   */
  bool IsInTaskQueue() const;

  /**
   * Initialize the canvas translator for a particular TextureType and
   * CanvasEventRingBuffer.
   *
   * @param aTextureType the TextureType the translator will create
   * @param aWebglTextureType the TextureType of any WebGL buffers
   * @param aBackendType the BackendType for texture data
   * @param aHeaderHandle handle for the control header
   * @param aBufferHandles handles for the initial buffers for translation
   * @param aBufferSize size of buffers and the default size
   * @param aReaderSem reading blocked semaphore for the CanvasEventRingBuffer
   * @param aWriterSem writing blocked semaphore for the CanvasEventRingBuffer
   */
  ipc::IPCResult RecvInitTranslator(TextureType aTextureType,
                                    TextureType aWebglTextureType,
                                    gfx::BackendType aBackendType,
                                    Handle&& aReadHandle,
                                    nsTArray<Handle>&& aBufferHandles,
                                    uint64_t aBufferSize,
                                    CrossProcessSemaphoreHandle&& aReaderSem,
                                    CrossProcessSemaphoreHandle&& aWriterSem);

  /**
   * Restart the translation from a Stopped state.
   */
  ipc::IPCResult RecvRestartTranslation();

  /**
   * Adds a new buffer to be translated. The current buffer will be recycled if
   * it is of the default size. The translation will then be restarted.
   */
  ipc::IPCResult RecvAddBuffer(Handle&& aBufferHandle, uint64_t aBufferSize);

  /**
   * Sets the shared memory to be used for readback.
   */
  ipc::IPCResult RecvSetDataSurfaceBuffer(Handle&& aBufferHandle,
                                          uint64_t aBufferSize);

  ipc::IPCResult RecvClearCachedResources();

  void ActorDestroy(ActorDestroyReason why) final;

  void CheckAndSignalWriter();

  /**
   * Translates events until no more are available or the end of a transaction
   * If this returns false the caller of this is responsible for re-calling
   * this function.
   */
  void TranslateRecording();

  /**
   * Marks the beginning of rendering for a transaction. While in a transaction
   * the translator will wait for a short time for events before returning.
   * When not in a transaction the translator will only translate one event at a
   * time.
   */
  void BeginTransaction();

  /**
   * Marks the end of a transaction.
   */
  void EndTransaction();

  /**
   * Flushes canvas drawing, for example to a device.
   */
  void Flush();

  /**
   * Marks that device change processing in the writing process has finished.
   */
  void DeviceChangeAcknowledged();

  /**
   * Used during playback of events to create DrawTargets. For the
   * CanvasTranslator this means creating TextureDatas and getting the
   * DrawTargets from those.
   *
   * @param aRefPtr the key to store the created DrawTarget against
   * @param aTextureId texture ID for this DrawTarget
   * @param aTextureOwnerId texture owner ID for this DrawTarget
   * @param aSize the size of the DrawTarget
   * @param aFormat the surface format for the DrawTarget
   * @returns the new DrawTarget
   */
  already_AddRefed<gfx::DrawTarget> CreateDrawTarget(
      gfx::ReferencePtr aRefPtr, int64_t aTextureId,
      RemoteTextureOwnerId aTextureOwnerId, const gfx::IntSize& aSize,
      gfx::SurfaceFormat aFormat);

  already_AddRefed<gfx::DrawTarget> CreateDrawTarget(
      gfx::ReferencePtr aRefPtr, const gfx::IntSize& aSize,
      gfx::SurfaceFormat aFormat) final;

  already_AddRefed<gfx::GradientStops> GetOrCreateGradientStops(
      gfx::DrawTarget* aDrawTarget, gfx::GradientStop* aRawStops,
      uint32_t aNumStops, gfx::ExtendMode aExtendMode) final;

  void CheckpointReached();

  void PauseTranslation();

  /**
   * Removes the texture and other objects associated with a texture ID.
   *
   * @param aTextureId the texture ID to remove
   */
  void RemoveTexture(int64_t aTextureId, RemoteTextureTxnType aTxnType = 0,
                     RemoteTextureTxnId aTxnId = 0);

  bool LockTexture(int64_t aTextureId, OpenMode aMode,
                   bool aInvalidContents = false);
  bool UnlockTexture(int64_t aTextureId);

  bool PresentTexture(int64_t aTextureId, RemoteTextureId aId);

  bool PushRemoteTexture(int64_t aTextureId, TextureData* aData,
                         RemoteTextureId aId, RemoteTextureOwnerId aOwnerId);

  /**
   * Overriden to remove any DataSourceSurfaces associated with the RefPtr.
   *
   * @param aRefPtr the key to the surface
   * @param aSurface the surface to store
   */
  void AddSourceSurface(gfx::ReferencePtr aRefPtr,
                        gfx::SourceSurface* aSurface) final {
    if (mMappedSurface == aRefPtr) {
      mPreparedMap = nullptr;
      mMappedSurface = nullptr;
    }
    RemoveDataSurface(aRefPtr);
    InlineTranslator::AddSourceSurface(aRefPtr, aSurface);
  }

  /**
   * Removes the SourceSurface and other objects associated with a SourceSurface
   * from another process.
   *
   * @param aRefPtr the key to the objects to remove
   */
  void RemoveSourceSurface(gfx::ReferencePtr aRefPtr) final {
    if (mMappedSurface == aRefPtr) {
      mPreparedMap = nullptr;
      mMappedSurface = nullptr;
    }
    RemoveDataSurface(aRefPtr);
    InlineTranslator::RemoveSourceSurface(aRefPtr);
  }

  already_AddRefed<gfx::SourceSurface> LookupExternalSurface(
      uint64_t aKey) final;

  /**
   * Gets the cached DataSourceSurface, if it exists, associated with a
   * SourceSurface from another process.
   *
   * @param aRefPtr the key used to find the DataSourceSurface
   * @returns the DataSourceSurface or nullptr if not found
   */
  gfx::DataSourceSurface* LookupDataSurface(gfx::ReferencePtr aRefPtr);

  /**
   * Used to cache the DataSourceSurface from a SourceSurface associated with a
   * SourceSurface from another process. This is to improve performance if we
   * require the data for that SourceSurface.
   *
   * @param aRefPtr the key used to store the DataSourceSurface
   * @param aSurface the DataSourceSurface to store
   */
  void AddDataSurface(gfx::ReferencePtr aRefPtr,
                      RefPtr<gfx::DataSourceSurface>&& aSurface);

  /**
   * Gets the cached DataSourceSurface, if it exists, associated with a
   * SourceSurface from another process.
   *
   * @param aRefPtr the key used to find the DataSourceSurface
   * @returns the DataSourceSurface or nullptr if not found
   */
  void RemoveDataSurface(gfx::ReferencePtr aRefPtr);

  /**
   * Sets a ScopedMap, to be used in a later event.
   *
   * @param aSurface the associated surface in the other process
   * @param aMap the ScopedMap to store
   */
  void SetPreparedMap(gfx::ReferencePtr aSurface,
                      UniquePtr<gfx::DataSourceSurface::ScopedMap> aMap);

  /**
   * Gets the ScopedMap stored using SetPreparedMap.
   *
   * @param aSurface must match the surface from the SetPreparedMap call
   * @returns the ScopedMap if aSurface matches otherwise nullptr
   */
  UniquePtr<gfx::DataSourceSurface::ScopedMap> GetPreparedMap(
      gfx::ReferencePtr aSurface);

  void PrepareShmem(int64_t aTextureId);

  void RecycleBuffer();

  void NextBuffer();

  void GetDataSurface(uint64_t aSurfaceRef);

 private:
  ~CanvasTranslator();

  void AddBuffer(Handle&& aBufferHandle, size_t aBufferSize);

  void SetDataSurfaceBuffer(Handle&& aBufferHandle, size_t aBufferSize);

  bool ReadNextEvent(EventType& aEventType);

  bool HasPendingEvent();

  bool ReadPendingEvent(EventType& aEventType);

  bool CheckDeactivated();

  void Deactivate();

  bool TryDrawTargetWebglFallback(int64_t aTextureId,
                                  gfx::DrawTargetWebgl* aWebgl);
  void ForceDrawTargetWebglFallback();

  void BlockCanvas();

  UniquePtr<TextureData> CreateTextureData(const gfx::IntSize& aSize,
                                           gfx::SurfaceFormat aFormat,
                                           bool aClear);

  void EnsureRemoteTextureOwner(
      RemoteTextureOwnerId aOwnerId = RemoteTextureOwnerId());

  UniquePtr<TextureData> CreateOrRecycleTextureData(const gfx::IntSize& aSize,
                                                    gfx::SurfaceFormat aFormat);

  already_AddRefed<gfx::DrawTarget> CreateFallbackDrawTarget(
      gfx::ReferencePtr aRefPtr, int64_t aTextureId,
      RemoteTextureOwnerId aTextureOwnerId, const gfx::IntSize& aSize,
      gfx::SurfaceFormat aFormat);

  void ClearTextureInfo();

  bool HandleExtensionEvent(int32_t aType);

  bool CreateReferenceTexture();
  bool CheckForFreshCanvasDevice(int aLineNumber);
  void NotifyDeviceChanged();

  bool EnsureSharedContextWebgl();
  gfx::DrawTargetWebgl* GetDrawTargetWebgl(int64_t aTextureId,
                                           bool aCheckForFallback = true) const;
  void NotifyRequiresRefresh(int64_t aTextureId, bool aDispatch = true);
  void CacheSnapshotShmem(int64_t aTextureId, bool aDispatch = true);

  void ClearCachedResources();

  const RefPtr<TaskQueue> mTranslationTaskQueue;
  const RefPtr<SharedSurfacesHolder> mSharedSurfacesHolder;
#if defined(XP_WIN)
  RefPtr<ID3D11Device> mDevice;
#endif
  RefPtr<gfx::SharedContextWebgl> mSharedContext;
  RefPtr<RemoteTextureOwnerClient> mRemoteTextureOwner;

  size_t mDefaultBufferSize = 0;
  uint32_t mMaxSpinCount;
  TimeDuration mNextEventTimeout;

  using State = CanvasDrawEventRecorder::State;
  using Header = CanvasDrawEventRecorder::Header;

  RefPtr<ipc::SharedMemoryBasic> mHeaderShmem;
  Header* mHeader = nullptr;

  struct CanvasShmem {
    RefPtr<ipc::SharedMemoryBasic> shmem;
    auto Size() { return shmem->Size(); }
    gfx::MemReader CreateMemReader() {
      return {static_cast<char*>(shmem->memory()), Size()};
    }
  };
  std::queue<CanvasShmem> mCanvasShmems;
  CanvasShmem mCurrentShmem;
  gfx::MemReader mCurrentMemReader{0, 0};
  RefPtr<ipc::SharedMemoryBasic> mDataSurfaceShmem;
  UniquePtr<CrossProcessSemaphore> mWriterSemaphore;
  UniquePtr<CrossProcessSemaphore> mReaderSemaphore;
  TextureType mTextureType = TextureType::Unknown;
  TextureType mWebglTextureType = TextureType::Unknown;
  UniquePtr<TextureData> mReferenceTextureData;
  dom::ContentParentId mContentId;
  uint32_t mManagerId;
  // Sometimes during device reset our reference DrawTarget can be null, so we
  // hold the BackendType separately.
  gfx::BackendType mBackendType = gfx::BackendType::NONE;
  base::ProcessId mOtherPid = base::kInvalidProcessId;
  struct TextureInfo {
    gfx::ReferencePtr mRefPtr;
    UniquePtr<TextureData> mTextureData;
    RefPtr<gfx::DrawTarget> mDrawTarget;
    RemoteTextureOwnerId mRemoteTextureOwnerId;
    bool mNotifiedRequiresRefresh = false;
    // Ref-count of how active uses of the DT. Avoids deletion when locked.
    int32_t mLocked = 1;
    OpenMode mTextureLockMode = OpenMode::OPEN_NONE;

    gfx::DrawTargetWebgl* GetDrawTargetWebgl(
        bool aCheckForFallback = true) const;
  };
  std::unordered_map<int64_t, TextureInfo> mTextureInfo;
  nsRefPtrHashtable<nsPtrHashKey<void>, gfx::DataSourceSurface> mDataSurfaces;
  gfx::ReferencePtr mMappedSurface;
  UniquePtr<gfx::DataSourceSurface::ScopedMap> mPreparedMap;
  Atomic<bool> mDeactivated{false};
  Atomic<bool> mBlocked{false};
  Atomic<bool> mIPDLClosed{false};
  bool mIsInTransaction = false;
  bool mDeviceResetInProgress = false;
};

}  // namespace layers
}  // namespace mozilla

#endif  // mozilla_layers_CanvasTranslator_h