gecko-dev/ipc/glue/PChildToParentStream.ipdl

/* 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/. */

include protocol PBackground;
include protocol PContent;
include protocol PContentBridge;

include "mozilla/layers/WebRenderMessageUtils.h";

using mozilla::wr::ByteBuffer from "mozilla/webrender/WebRenderTypes.h";

namespace mozilla {
namespace ipc {

// This is protocol is the opposite of PParentToChildStream. Please keep these
// protocols in sync.
protocol PChildToParentStream
{
  manager PBackground or PContent or PContentBridge;

parent:
  async Buffer(ByteBuffer aBuffer);
  async Close(nsresult aRv);

child:
  // The remote stream can be used in 2 ways: it can start receiving data
  // immediately after the creation of the child actor, or it can wait until
  // the child stream is actually used. This second configuration is enabled by
  // passing 'true' to delayedStart in AutoIPCStream CTOR.
  // If we are delaying the reading, at the first use of the remote stream, we
  // must activate the sending of data. This happens by calling this method.
  async StartReading();

  // The parent side has hit an error condition and has requested the child
  // actor issue a Close() message.  The close must be initiated by the child
  // to avoid racing with an in-flight Buffer() message.
  async RequestClose(nsresult aRv);

  // Stream is always destroyed from the parent side.  This occurs if the
  // parent encounters an error while writing to its pipe or if the child
  // signals the stream should close by SendClose().
  async __delete__();
};

} // namespace ipc
} // namespace mozilla