Added ImagePipe

mojo/services/gfx/images/cpp/image_pipe_consumer_endpoint.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 MOJO_SERVICES_GFX_IMAGES_INTERFACES_IMAGE_PIPE_CONSUMER_ENDPOINT_H_
+#define MOJO_SERVICES_GFX_IMAGES_INTERFACES_IMAGE_PIPE_CONSUMER_ENDPOINT_H_
+
+#include "image_pipe_endpoint.h"
+#include "mojo/public/c/system/macros.h"
+#include "mojo/public/cpp/bindings/strong_binding.h"
+#include "mojo/services/gfx/images/cpp/image_pipe_consumer_delegate.h"
+#include "mojo/services/gfx/images/interfaces/image_pipe.mojom.h"
+
+namespace image_pipe {
+
+// |ImagePipeConsumerEndpoint| is a state tracking wrapper for the consumer end
+// of an |ImagePipe| that enforces the constraints documented in the mojom
+// interface. Using |ImagePipeConsumerEndpoint| is not required to use
+// |ImagePipe|, but it may help you use it correctly
+class ImagePipeConsumerEndpoint : private mojo::gfx::ImagePipe {
+ public:
+  ImagePipeConsumerEndpoint(
+      mojo::InterfaceRequest<mojo::gfx::ImagePipe> request,
+      ImagePipeConsumerDelegate* delegate);
+  ~ImagePipeConsumerEndpoint() override;
+
+  // Aquire the Image presented least recently (queue like behavior). If no
+  // images are available that match the selection criteria this function will
+  // return false otherwise it will write the selected id into its id argument
+  // and return true.
+  bool AcquireNextImage(uint32_t* out_id);
+
+  // Releases an image back to the producer.
+  void ReleaseImage(uint32_t id, mojo::gfx::PresentationStatus status);
+
+  // For testing only, makes fatal errors not quite fatal, which allows tests
+  // to cause a fatal error and check that it was caught correctly without
+  // dying a horrible death in the process. If you are using this for something
+  // other than testing you are probably doing something very wrong.
+  void DisableFatalErrorsForTesting();
+
+ private:
+  void CloseEndpoint();
+
+  // Inherited from mojo::gfx::ImagePipe, see image_pipe.mojom for comments
+  void AddImage(mojo::gfx::ImagePtr image, uint32_t id) override;
+  void RemoveImage(uint32_t id) override;
+  void PresentImage(uint32_t id, const PresentImageCallback& callback) override;
+  void FlushImages() override;
+
+  ImagePipeEndpoint state_tracker_;
+  ImagePipeConsumerDelegate* delegate_;
+
+  mojo::Binding<mojo::gfx::ImagePipe> image_pipe_binding_;
+
+  MOJO_DISALLOW_COPY_AND_ASSIGN(ImagePipeConsumerEndpoint);
+};
+
+}  // namespace image_pipe
+
+#endif  // MOJO_SERVICES_GFX_IMAGES_INTERFACES_IMAGE_PIPE_CONSUMER_ENDPOINT_H_