Added ImagePipe

mojo/services/gfx/images/cpp/image_pipe_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_CPP_IMAGE_PIPE_ENDPOINT_H_
+#define MOJO_SERVICES_GFX_IMAGES_CPP_IMAGE_PIPE_ENDPOINT_H_
+
+#include <deque>
+#include <string>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+
+#include "mojo/public/c/system/macros.h"
+#include "mojo/services/gfx/images/interfaces/image_pipe.mojom.h"
+
+namespace image_pipe {
+
+class ImagePipeEndpoint {
+ public:
+  ImagePipeEndpoint(bool is_producer,
+                    std::function<void()> fatal_error_handler);
+  virtual ~ImagePipeEndpoint();
+
+  void ProducerFatalError(const std::string& message, uint32_t id);
+  void ConsumerFatalError(const std::string& message, uint32_t id);
+
+  bool AcquireNextImage(uint32_t* out_id);
+
+  void ProducerAdd(uint32_t id);
+  void ProducerRemove(uint32_t id);
+  void ProducerPresent(uint32_t id,
+                       mojo::gfx::ImagePipe::PresentImageCallback callback);
+  void ConsumerRelease(uint32_t id, mojo::gfx::PresentationStatus status);
+  void ProducerFlush();
+
+  // 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:
+  bool IsInPool(uint32_t id) const;
+  bool IsConsumerOwned(uint32_t id) const;
+  bool IsConsumerAcquirable(uint32_t id) const;
+  bool IsProducerOwned(uint32_t id) const;
+  bool IsProducerAcquirable(uint32_t id) const;
+  void CallPresentCallback(uint32_t id, mojo::gfx::PresentationStatus status);
+  void ReleaseInternal(uint32_t id, bool released_by_producer);
+
+  static void ImagePipeLogError(const std::string& entity,
+                                const std::string& message,
+                                uint32_t id);
+
+  // Used for internal state tracking and validation
+  std::unordered_map<uint32_t, mojo::gfx::ImagePipe::PresentImageCallback>
+      present_callback_map_;
+
+  // ids that have been added to the pipe's image pool and have not been removed
+  std::unordered_set<uint32_t> image_pool_ids_;
+
+  // images that have been aquired by the consumer
+  std::unordered_set<uint32_t> consumer_owned_ids_;
+  // images that have been presented by the producer but have not been aquired
+  // by the consumer
+  std::deque<uint32_t> consumer_acquirable_ids_;
+
+  // images that have been aquired by the producer
+  std::unordered_set<uint32_t> producer_owned_ids_;
+  // images that have been released by the producer but have not been aquired
+  // by the consumer
+  std::deque<uint32_t> producer_acquirable_ids_;
+
+  bool is_producer_;
+  bool is_checked_;
+  std::function<void()> fatal_error_handler_;
+};
+}
+
+#endif  // MOJO_SERVICES_GFX_IMAGES_CPP_IMAGE_PIPE_ENDPOINT_H_