diff options
Diffstat (limited to 'dom/media/imagecapture/ImageCapture.cpp')
| -rw-r--r-- | dom/media/imagecapture/ImageCapture.cpp | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/dom/media/imagecapture/ImageCapture.cpp b/dom/media/imagecapture/ImageCapture.cpp new file mode 100644 index 0000000000..d32c22d054 --- /dev/null +++ b/dom/media/imagecapture/ImageCapture.cpp @@ -0,0 +1,212 @@ +/* -*- 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 "ImageCapture.h" +#include "mozilla/dom/BlobEvent.h" +#include "mozilla/dom/DOMException.h" +#include "mozilla/dom/Event.h" +#include "mozilla/dom/File.h" +#include "mozilla/dom/ImageCaptureError.h" +#include "mozilla/dom/ImageCaptureErrorEvent.h" +#include "mozilla/dom/ImageCaptureErrorEventBinding.h" +#include "mozilla/dom/VideoStreamTrack.h" +#include "mozilla/dom/Document.h" +#include "CaptureTask.h" +#include "MediaEngineSource.h" + +namespace mozilla { + +LogModule* GetICLog() { + static LazyLogModule log("ImageCapture"); + return log; +} + +namespace dom { + +NS_IMPL_CYCLE_COLLECTION_INHERITED(ImageCapture, DOMEventTargetHelper, mTrack) + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ImageCapture) +NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper) + +NS_IMPL_ADDREF_INHERITED(ImageCapture, DOMEventTargetHelper) +NS_IMPL_RELEASE_INHERITED(ImageCapture, DOMEventTargetHelper) + +ImageCapture::ImageCapture(VideoStreamTrack* aTrack, + nsPIDOMWindowInner* aOwnerWindow) + : DOMEventTargetHelper(aOwnerWindow), mTrack(aTrack) { + MOZ_ASSERT(aOwnerWindow); + MOZ_ASSERT(aTrack); +} + +ImageCapture::~ImageCapture() { MOZ_ASSERT(NS_IsMainThread()); } + +already_AddRefed<ImageCapture> ImageCapture::Constructor( + const GlobalObject& aGlobal, MediaStreamTrack& aTrack, ErrorResult& aRv) { + nsCOMPtr<nsPIDOMWindowInner> win = do_QueryInterface(aGlobal.GetAsSupports()); + if (!win) { + aRv.Throw(NS_ERROR_FAILURE); + return nullptr; + } + + if (!aTrack.AsVideoStreamTrack()) { + aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR); + return nullptr; + } + + RefPtr<ImageCapture> object = + new ImageCapture(aTrack.AsVideoStreamTrack(), win); + + return object.forget(); +} + +MediaStreamTrack* ImageCapture::GetVideoStreamTrack() const { return mTrack; } + +nsresult ImageCapture::TakePhotoByMediaEngine() { + // Callback for TakPhoto(), it also monitor the principal. If principal + // changes, it returns PHOTO_ERROR with security error. + class TakePhotoCallback : public MediaEnginePhotoCallback, + public PrincipalChangeObserver<MediaStreamTrack> { + public: + TakePhotoCallback(VideoStreamTrack* aVideoTrack, + ImageCapture* aImageCapture) + : mVideoTrack(aVideoTrack), + mImageCapture(aImageCapture), + mPrincipalChanged(false) { + MOZ_ASSERT(NS_IsMainThread()); + mVideoTrack->AddPrincipalChangeObserver(this); + } + + void PrincipalChanged(MediaStreamTrack* aMediaStream) override { + mPrincipalChanged = true; + } + + nsresult PhotoComplete(already_AddRefed<Blob> aBlob) override { + RefPtr<Blob> blob = aBlob; + + if (mPrincipalChanged) { + return PhotoError(NS_ERROR_DOM_SECURITY_ERR); + } + return mImageCapture->PostBlobEvent(blob); + } + + nsresult PhotoError(nsresult aRv) override { + return mImageCapture->PostErrorEvent(ImageCaptureError::PHOTO_ERROR, aRv); + } + + protected: + ~TakePhotoCallback() { + MOZ_ASSERT(NS_IsMainThread()); + mVideoTrack->RemovePrincipalChangeObserver(this); + } + + const RefPtr<VideoStreamTrack> mVideoTrack; + const RefPtr<ImageCapture> mImageCapture; + bool mPrincipalChanged; + }; + + RefPtr<MediaEnginePhotoCallback> callback = + new TakePhotoCallback(mTrack, this); + return mTrack->GetSource().TakePhoto(callback); +} + +void ImageCapture::TakePhoto(ErrorResult& aResult) { + // According to spec, MediaStreamTrack.readyState must be "live"; however + // gecko doesn't implement it yet (bug 910249). Instead of readyState, we + // check MediaStreamTrack.enable before bug 910249 is fixed. + // The error code should be INVALID_TRACK, but spec doesn't define it in + // ImageCaptureError. So it returns PHOTO_ERROR here before spec updates. + if (!mTrack->Enabled()) { + PostErrorEvent(ImageCaptureError::PHOTO_ERROR, NS_ERROR_FAILURE); + return; + } + + // Try if MediaEngine supports taking photo. + nsresult rv = TakePhotoByMediaEngine(); + + // It falls back to MediaTrackGraph image capture if MediaEngine doesn't + // support TakePhoto(). + if (rv == NS_ERROR_NOT_IMPLEMENTED) { + IC_LOG( + "MediaEngine doesn't support TakePhoto(), it falls back to " + "MediaTrackGraph."); + RefPtr<CaptureTask> task = new CaptureTask(this); + + // It adds itself into MediaTrackGraph, so ImageCapture doesn't need to + // hold the reference. + task->AttachTrack(); + } +} + +nsresult ImageCapture::PostBlobEvent(Blob* aBlob) { + MOZ_ASSERT(NS_IsMainThread()); + if (!CheckPrincipal()) { + // Media is not same-origin, don't allow the data out. + return PostErrorEvent(ImageCaptureError::PHOTO_ERROR, + NS_ERROR_DOM_SECURITY_ERR); + } + + BlobEventInit init; + init.mBubbles = false; + init.mCancelable = false; + init.mData = aBlob; + + RefPtr<BlobEvent> blob_event = + BlobEvent::Constructor(this, u"photo"_ns, init); + + return DispatchTrustedEvent(blob_event); +} + +nsresult ImageCapture::PostErrorEvent(uint16_t aErrorCode, nsresult aReason) { + MOZ_ASSERT(NS_IsMainThread()); + nsresult rv = CheckCurrentGlobalCorrectness(); + NS_ENSURE_SUCCESS(rv, rv); + + nsString errorMsg; + if (NS_FAILED(aReason)) { + nsCString name, message; + rv = NS_GetNameAndMessageForDOMNSResult(aReason, name, message); + if (NS_SUCCEEDED(rv)) { + CopyASCIItoUTF16(message, errorMsg); + } + } + + RefPtr<ImageCaptureError> error = new ImageCaptureError( + static_cast<EventTarget*>(this), aErrorCode, errorMsg); + + ImageCaptureErrorEventInit init; + init.mBubbles = false; + init.mCancelable = false; + init.mImageCaptureError = error; + + RefPtr<Event> event = + ImageCaptureErrorEvent::Constructor(this, u"error"_ns, init); + + return DispatchTrustedEvent(event); +} + +bool ImageCapture::CheckPrincipal() { + MOZ_ASSERT(NS_IsMainThread()); + + nsCOMPtr<nsIPrincipal> principal = mTrack->GetPrincipal(); + + if (!GetOwner()) { + return false; + } + nsCOMPtr<Document> doc = GetOwner()->GetExtantDoc(); + if (!doc || !principal) { + return false; + } + + bool subsumes; + if (NS_FAILED(doc->NodePrincipal()->Subsumes(principal, &subsumes))) { + return false; + } + + return subsumes; +} + +} // namespace dom +} // namespace mozilla |