Added ImagePipe
ImagePipe is a Mojo interface designed to provide synchronized transport of
graphics buffers residing on the GPU (though in principle it could be used for
the transport of any type media buffer that can be accessed via a mojo handle).
The semantics of this interface are designed mainly to support the creation of
accelerated rendering contexts (e.g. OpenGL contexts) whose output is consumed
by a different Mojo application than the one doing the rendering.
This interface can be used directly, but we also provide endpoint classes which
provide state tracking and state validation functionality, which should
generally be used unless there is a compeeling reason not to.
Change-Id: I389ec3519314da2623a65051ef9786282a28e3ac
BUG=
R=jeffbrown@google.com
Review URL: https://codereview.chromium.org/1595773002 .
diff --git a/mojo/services/gfx/images/cpp/image_pipe_producer_endpoint.h b/mojo/services/gfx/images/cpp/image_pipe_producer_endpoint.h
new file mode 100644
index 0000000..d2cbbf9
--- /dev/null
+++ b/mojo/services/gfx/images/cpp/image_pipe_producer_endpoint.h
@@ -0,0 +1,70 @@
+// 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_PRODUCER_ENDPOINT_H_
+#define MOJO_SERVICES_GFX_IMAGES_INTERFACES_IMAGE_PIPE_PRODUCER_ENDPOINT_H_
+
+#include "image_pipe_endpoint.h"
+#include "mojo/public/c/system/macros.h"
+#include "mojo/services/gfx/images/interfaces/image_pipe.mojom.h"
+
+namespace image_pipe {
+
+// This class wraps the producer end of an ImagePipe and validates the sanity
+// of both the producer actions and the consumer actions coming over the
+// message pipe. It also tracks the state of Images in the pipe's image pool
+// and provides conviennce mechanisms for accessing this state (like the ability
+// to get the ID of an available image without having to manually track the
+// lifecycle of these images.
+class ImagePipeProducerEndpoint : public mojo::gfx::ImagePipe {
+ public:
+ ImagePipeProducerEndpoint(mojo::gfx::ImagePipePtr image_pipe,
+ std::function<void()> endpoint_closed_callback);
+
+ ~ImagePipeProducerEndpoint() override;
+
+ // Ask the endpoint for an available image to draw into
+ // returns false if no images are available, otherwise returns true and
+ // sets |id| to the acquired ID.
+ bool AcquireImage(uint32_t* out_id);
+
+ // The blocking version of the above function. This function will block until
+ // an Image is available or the deadline is met. If there are no images in the
+ // pool or the underlying message pipe has errors then false will be returned
+ bool AcquireImageBlocking(uint32_t* out_id, MojoDeadline deadline);
+
+ // 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;
+
+ // Returns true if and only if the message pipe underlying the image pipe has
+ // enountered errors or closed
+ bool HasEncounteredError();
+
+ // 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();
+
+ // This exists wrap ImagePipeEndpoint::ConsumerRelease because for some reason
+ // GCC doesnt like us calling protected methods on our base class from inside
+ // a lambda that captures 'this', which breaks the fnl build. Clang handles it
+ // fine, but its unclear whos right here, so we trampoline it as a workaround
+ void ConsumerReleaseInternal(uint32_t id,
+ mojo::gfx::PresentationStatus status);
+
+ ImagePipeEndpoint state_tracker_;
+ mojo::gfx::ImagePipePtr image_pipe_ptr_;
+ std::function<void()> endpoint_closed_callback_;
+};
+
+} // namespace image_pipe
+
+#endif // MOJO_SERVICES_GFX_IMAGES_INTERFACES_IMAGE_PIPE_PRODUCER_ENDPOINT_H_
\ No newline at end of file
