gecko-dev/content/media/webaudio/MediaStreamAudioSourceNode.cpp
Ehsan Akhgari 0ab5221feb Bug 1015783 - Add a devtools API for Web Audio; r=padenot,smaug
See bug 980506 for an extensive discussion about this.  This patch adds
three APIs to AudioNode in order for us to be able to build awesome
devtools on top of it.

* Weak reference API.
  This patch allows one to hold a weak reference to all AudioNode's
  using Components.utils.getWeakReference().  That way, the devtool's
  inspection code would not change the lifetime of AudioNodes.
* AudioNode.id
  This is a chrome-only unique and monotonically incrementing ID for
  AudioNode objects.  It is supposed to be used in order for the
  devtools to be able to identify a node without having to keep it
  alive.
* webaudio-node-demise
  This is an observer notification that is called every time an
  AudioNode gets destroyed inside Gecko.  The ID of the corresponding
  node is passed to this notification.

--HG--
extra : rebase_source : 83246a990489daf44ddc97dd4ea372a8cebe8e00
2014-06-03 22:51:48 -04:00

122 lines
4.3 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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 "MediaStreamAudioSourceNode.h"
#include "mozilla/dom/MediaStreamAudioSourceNodeBinding.h"
#include "AudioNodeEngine.h"
#include "AudioNodeExternalInputStream.h"
#include "nsIDocument.h"
namespace mozilla {
namespace dom {
NS_IMPL_CYCLE_COLLECTION_CLASS(MediaStreamAudioSourceNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(MediaStreamAudioSourceNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mInputStream)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END_INHERITED(AudioNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(MediaStreamAudioSourceNode, AudioNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInputStream)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(MediaStreamAudioSourceNode)
NS_INTERFACE_MAP_END_INHERITING(AudioNode)
NS_IMPL_ADDREF_INHERITED(MediaStreamAudioSourceNode, AudioNode)
NS_IMPL_RELEASE_INHERITED(MediaStreamAudioSourceNode, AudioNode)
MediaStreamAudioSourceNode::MediaStreamAudioSourceNode(AudioContext* aContext,
DOMMediaStream* aMediaStream)
: AudioNode(aContext,
2,
ChannelCountMode::Max,
ChannelInterpretation::Speakers),
mInputStream(aMediaStream)
{
AudioNodeEngine* engine = new MediaStreamAudioSourceNodeEngine(this);
mStream = aContext->Graph()->CreateAudioNodeExternalInputStream(engine);
ProcessedMediaStream* outputStream = static_cast<ProcessedMediaStream*>(mStream.get());
mInputPort = outputStream->AllocateInputPort(aMediaStream->GetStream(),
MediaInputPort::FLAG_BLOCK_INPUT);
mInputStream->AddConsumerToKeepAlive(static_cast<nsIDOMEventTarget*>(this));
PrincipalChanged(mInputStream); // trigger enabling/disabling of the connector
mInputStream->AddPrincipalChangeObserver(this);
}
MediaStreamAudioSourceNode::~MediaStreamAudioSourceNode()
{
if (mInputStream) {
mInputStream->RemovePrincipalChangeObserver(this);
}
}
/**
* Changes the principal. Note that this will be called on the main thread, but
* changes will be enacted on the MediaStreamGraph thread. If the principal
* change results in the document principal losing access to the stream, then
* there needs to be other measures in place to ensure that any media that is
* governed by the new stream principal is not available to the Media Stream
* Graph before this change completes. Otherwise, a site could get access to
* media that they are not authorized to receive.
*
* One solution is to block the altered content, call this method, then dispatch
* another change request to the MediaStreamGraph thread that allows the content
* under the new principal to flow. This might be unnecessary if the principal
* change is changing to be the document principal.
*/
void
MediaStreamAudioSourceNode::PrincipalChanged(DOMMediaStream* ms)
{
bool subsumes = false;
nsIDocument* doc = Context()->GetParentObject()->GetExtantDoc();
if (doc) {
nsIPrincipal* docPrincipal = doc->NodePrincipal();
nsIPrincipal* streamPrincipal = mInputStream->GetPrincipal();
if (NS_FAILED(docPrincipal->Subsumes(streamPrincipal, &subsumes))) {
subsumes = false;
}
}
auto stream = static_cast<AudioNodeExternalInputStream*>(mStream.get());
stream->SetInt32Parameter(MediaStreamAudioSourceNodeEngine::ENABLE, subsumes);
}
size_t
MediaStreamAudioSourceNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
{
// Future:
// - mInputStream
size_t amount = AudioNode::SizeOfExcludingThis(aMallocSizeOf);
amount += mInputPort->SizeOfIncludingThis(aMallocSizeOf);
return amount;
}
size_t
MediaStreamAudioSourceNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
{
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
void
MediaStreamAudioSourceNode::DestroyMediaStream()
{
if (mInputPort) {
mInputPort->Destroy();
mInputPort = nullptr;
}
AudioNode::DestroyMediaStream();
}
JSObject*
MediaStreamAudioSourceNode::WrapObject(JSContext* aCx)
{
return MediaStreamAudioSourceNodeBinding::Wrap(aCx, this);
}
}
}