1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7 #include "ImageCapture.h"
8 #include "mozilla/dom/BlobEvent.h"
9 #include "mozilla/dom/DOMException.h"
10 #include "mozilla/dom/Event.h"
11 #include "mozilla/dom/File.h"
12 #include "mozilla/dom/ImageCaptureError.h"
13 #include "mozilla/dom/ImageCaptureErrorEvent.h"
14 #include "mozilla/dom/ImageCaptureErrorEventBinding.h"
15 #include "mozilla/dom/VideoStreamTrack.h"
16 #include "mozilla/dom/Document.h"
17 #include "CaptureTask.h"
18 #include "MediaEngineSource.h"
19
20 namespace mozilla {
21
GetICLog()22 LogModule* GetICLog() {
23 static LazyLogModule log("ImageCapture");
24 return log;
25 }
26
27 namespace dom {
28
NS_IMPL_CYCLE_COLLECTION_INHERITED(ImageCapture,DOMEventTargetHelper,mTrack)29 NS_IMPL_CYCLE_COLLECTION_INHERITED(ImageCapture, DOMEventTargetHelper, mTrack)
30
31 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ImageCapture)
32 NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
33
34 NS_IMPL_ADDREF_INHERITED(ImageCapture, DOMEventTargetHelper)
35 NS_IMPL_RELEASE_INHERITED(ImageCapture, DOMEventTargetHelper)
36
37 ImageCapture::ImageCapture(VideoStreamTrack* aTrack,
38 nsPIDOMWindowInner* aOwnerWindow)
39 : DOMEventTargetHelper(aOwnerWindow), mTrack(aTrack) {
40 MOZ_ASSERT(aOwnerWindow);
41 MOZ_ASSERT(aTrack);
42 }
43
~ImageCapture()44 ImageCapture::~ImageCapture() { MOZ_ASSERT(NS_IsMainThread()); }
45
Constructor(const GlobalObject & aGlobal,MediaStreamTrack & aTrack,ErrorResult & aRv)46 already_AddRefed<ImageCapture> ImageCapture::Constructor(
47 const GlobalObject& aGlobal, MediaStreamTrack& aTrack, ErrorResult& aRv) {
48 nsCOMPtr<nsPIDOMWindowInner> win = do_QueryInterface(aGlobal.GetAsSupports());
49 if (!win) {
50 aRv.Throw(NS_ERROR_FAILURE);
51 return nullptr;
52 }
53
54 if (!aTrack.AsVideoStreamTrack()) {
55 aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
56 return nullptr;
57 }
58
59 RefPtr<ImageCapture> object =
60 new ImageCapture(aTrack.AsVideoStreamTrack(), win);
61
62 return object.forget();
63 }
64
GetVideoStreamTrack() const65 MediaStreamTrack* ImageCapture::GetVideoStreamTrack() const { return mTrack; }
66
TakePhotoByMediaEngine()67 nsresult ImageCapture::TakePhotoByMediaEngine() {
68 // Callback for TakPhoto(), it also monitor the principal. If principal
69 // changes, it returns PHOTO_ERROR with security error.
70 class TakePhotoCallback : public MediaEnginePhotoCallback,
71 public PrincipalChangeObserver<MediaStreamTrack> {
72 public:
73 TakePhotoCallback(VideoStreamTrack* aVideoTrack,
74 ImageCapture* aImageCapture)
75 : mVideoTrack(aVideoTrack),
76 mImageCapture(aImageCapture),
77 mPrincipalChanged(false) {
78 MOZ_ASSERT(NS_IsMainThread());
79 mVideoTrack->AddPrincipalChangeObserver(this);
80 }
81
82 void PrincipalChanged(MediaStreamTrack* aMediaStream) override {
83 mPrincipalChanged = true;
84 }
85
86 nsresult PhotoComplete(already_AddRefed<Blob> aBlob) override {
87 RefPtr<Blob> blob = aBlob;
88
89 if (mPrincipalChanged) {
90 return PhotoError(NS_ERROR_DOM_SECURITY_ERR);
91 }
92 return mImageCapture->PostBlobEvent(blob);
93 }
94
95 nsresult PhotoError(nsresult aRv) override {
96 return mImageCapture->PostErrorEvent(ImageCaptureError::PHOTO_ERROR, aRv);
97 }
98
99 protected:
100 ~TakePhotoCallback() {
101 MOZ_ASSERT(NS_IsMainThread());
102 mVideoTrack->RemovePrincipalChangeObserver(this);
103 }
104
105 const RefPtr<VideoStreamTrack> mVideoTrack;
106 const RefPtr<ImageCapture> mImageCapture;
107 bool mPrincipalChanged;
108 };
109
110 RefPtr<MediaEnginePhotoCallback> callback =
111 new TakePhotoCallback(mTrack, this);
112 return mTrack->GetSource().TakePhoto(callback);
113 }
114
TakePhoto(ErrorResult & aResult)115 void ImageCapture::TakePhoto(ErrorResult& aResult) {
116 // According to spec, MediaStreamTrack.readyState must be "live"; however
117 // gecko doesn't implement it yet (bug 910249). Instead of readyState, we
118 // check MediaStreamTrack.enable before bug 910249 is fixed.
119 // The error code should be INVALID_TRACK, but spec doesn't define it in
120 // ImageCaptureError. So it returns PHOTO_ERROR here before spec updates.
121 if (!mTrack->Enabled()) {
122 PostErrorEvent(ImageCaptureError::PHOTO_ERROR, NS_ERROR_FAILURE);
123 return;
124 }
125
126 // Try if MediaEngine supports taking photo.
127 nsresult rv = TakePhotoByMediaEngine();
128
129 // It falls back to MediaTrackGraph image capture if MediaEngine doesn't
130 // support TakePhoto().
131 if (rv == NS_ERROR_NOT_IMPLEMENTED) {
132 IC_LOG(
133 "MediaEngine doesn't support TakePhoto(), it falls back to "
134 "MediaTrackGraph.");
135 RefPtr<CaptureTask> task = new CaptureTask(this);
136
137 // It adds itself into MediaTrackGraph, so ImageCapture doesn't need to
138 // hold the reference.
139 task->AttachTrack();
140 }
141 }
142
PostBlobEvent(Blob * aBlob)143 nsresult ImageCapture::PostBlobEvent(Blob* aBlob) {
144 MOZ_ASSERT(NS_IsMainThread());
145 if (!CheckPrincipal()) {
146 // Media is not same-origin, don't allow the data out.
147 return PostErrorEvent(ImageCaptureError::PHOTO_ERROR,
148 NS_ERROR_DOM_SECURITY_ERR);
149 }
150
151 BlobEventInit init;
152 init.mBubbles = false;
153 init.mCancelable = false;
154 init.mData = aBlob;
155
156 RefPtr<BlobEvent> blob_event =
157 BlobEvent::Constructor(this, u"photo"_ns, init);
158
159 return DispatchTrustedEvent(blob_event);
160 }
161
PostErrorEvent(uint16_t aErrorCode,nsresult aReason)162 nsresult ImageCapture::PostErrorEvent(uint16_t aErrorCode, nsresult aReason) {
163 MOZ_ASSERT(NS_IsMainThread());
164 nsresult rv = CheckCurrentGlobalCorrectness();
165 NS_ENSURE_SUCCESS(rv, rv);
166
167 nsString errorMsg;
168 if (NS_FAILED(aReason)) {
169 nsCString name, message;
170 rv = NS_GetNameAndMessageForDOMNSResult(aReason, name, message);
171 if (NS_SUCCEEDED(rv)) {
172 CopyASCIItoUTF16(message, errorMsg);
173 }
174 }
175
176 RefPtr<ImageCaptureError> error =
177 new ImageCaptureError(this, aErrorCode, errorMsg);
178
179 ImageCaptureErrorEventInit init;
180 init.mBubbles = false;
181 init.mCancelable = false;
182 init.mImageCaptureError = error;
183
184 RefPtr<Event> event =
185 ImageCaptureErrorEvent::Constructor(this, u"error"_ns, init);
186
187 return DispatchTrustedEvent(event);
188 }
189
CheckPrincipal()190 bool ImageCapture::CheckPrincipal() {
191 MOZ_ASSERT(NS_IsMainThread());
192
193 nsCOMPtr<nsIPrincipal> principal = mTrack->GetPrincipal();
194
195 if (!GetOwner()) {
196 return false;
197 }
198 nsCOMPtr<Document> doc = GetOwner()->GetExtantDoc();
199 if (!doc || !principal) {
200 return false;
201 }
202
203 bool subsumes;
204 if (NS_FAILED(doc->NodePrincipal()->Subsumes(principal, &subsumes))) {
205 return false;
206 }
207
208 return subsumes;
209 }
210
211 } // namespace dom
212 } // namespace mozilla
213