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/* -*- 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
#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
// 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