1 files changed, 90 insertions, 0 deletions
diff --git a/gfx/layers/ipc/TextureForwarder.h b/gfx/layers/ipc/TextureForwarder.h
new file mode 100644
index 0000000000..28a2d861ff
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+++ b/gfx/layers/ipc/TextureForwarder.h
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+/* -*- 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 http://mozilla.org/MPL/2.0/. */
+
+#ifndef MOZILLA_LAYERS_TEXTUREFORWARDER
+#define MOZILLA_LAYERS_TEXTUREFORWARDER
+
+#include <stdint.h>  // for int32_t, uint64_t
+#include "gfxTypes.h"
+#include "mozilla/ipc/ProtocolUtils.h"
+#include "mozilla/layers/LayersMessages.h"  // for Edit, etc
+#include "mozilla/layers/LayersTypes.h"     // for LayersBackend
+#include "mozilla/layers/TextureClient.h"   // for TextureClient
+#include "mozilla/layers/KnowsCompositor.h"
+#include "nsISerialEventTarget.h"
+
+namespace mozilla {
+namespace layers {
+class CanvasChild;
+
+/**
+ * An abstract interface for classes that implement the autogenerated
+ * IPDL actor class. Lets us check if they are still valid for IPC.
+ */
+class LayersIPCActor {
+ public:
+  virtual bool IPCOpen() const { return true; }
+};
+
+/**
+ * An abstract interface for LayersIPCActors that implement a top-level
+ * IPDL protocol so also have their own channel.
+ * Has their own MessageLoop for message dispatch, and can allocate
+ * shmem.
+ */
+class LayersIPCChannel : public LayersIPCActor,
+                         public mozilla::ipc::IShmemAllocator {
+ public:
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  virtual bool IsSameProcess() const = 0;
+
+  virtual bool UsesImageBridge() const { return false; }
+
+  virtual base::ProcessId GetParentPid() const = 0;
+
+  virtual nsISerialEventTarget* GetThread() const = 0;
+
+  virtual FixedSizeSmallShmemSectionAllocator* GetTileLockAllocator() {
+    return nullptr;
+  }
+
+  virtual void CancelWaitForNotifyNotUsed(uint64_t aTextureId) = 0;
+
+  virtual wr::MaybeExternalImageId GetNextExternalImageId() {
+    return Nothing();
+  }
+
+ protected:
+  virtual ~LayersIPCChannel() = default;
+};
+
+/**
+ * An abstract interface for classes that can allocate PTexture objects
+ * across IPDL. Currently a sub-class of LayersIPCChannel for simplicity
+ * since all our implementations use both, but could be independant if needed.
+ */
+class TextureForwarder : public LayersIPCChannel {
+ public:
+  /**
+   * Create a TextureChild/Parent pair as as well as the TextureHost on the
+   * parent side.
+   */
+  virtual PTextureChild* CreateTexture(
+      const SurfaceDescriptor& aSharedData, ReadLockDescriptor&& aReadLock,
+      LayersBackend aLayersBackend, TextureFlags aFlags, uint64_t aSerial,
+      wr::MaybeExternalImageId& aExternalImageId) = 0;
+
+  /**
+   * Returns the CanvasChild for this TextureForwarder.
+   */
+  virtual already_AddRefed<CanvasChild> GetCanvasChild() { return nullptr; };
+};
+
+}  // namespace layers
+}  // namespace mozilla
+
+#endif