1/*
2 * Copyright (C) 2011, 2013 Google Inc. All rights reserved.
3 * Copyright (C) 2011-2017 Apple Inc. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "config.h"
28#include "HTMLTrackElement.h"
29
30#if ENABLE(VIDEO_TRACK)
31
32#include "ContentSecurityPolicy.h"
33#include "Event.h"
34#include "EventNames.h"
35#include "HTMLMediaElement.h"
36#include "HTMLNames.h"
37#include "Logging.h"
38#include "RuntimeEnabledFeatures.h"
39#include <wtf/IsoMallocInlines.h>
40#include <wtf/text/CString.h>
41
42namespace WebCore {
43
44WTF_MAKE_ISO_ALLOCATED_IMPL(HTMLTrackElement);
45
46using namespace HTMLNames;
47
48#if !LOG_DISABLED
49
50static String urlForLoggingTrack(const URL& url)
51{
52 static const unsigned maximumURLLengthForLogging = 128;
53
54 if (url.string().length() < maximumURLLengthForLogging)
55 return url.string();
56 return url.string().substring(0, maximumURLLengthForLogging) + "...";
57}
58
59#endif
60
61inline HTMLTrackElement::HTMLTrackElement(const QualifiedName& tagName, Document& document)
62 : HTMLElement(tagName, document)
63 , m_loadTimer(*this, &HTMLTrackElement::loadTimerFired)
64{
65 LOG(Media, "HTMLTrackElement::HTMLTrackElement - %p", this);
66 ASSERT(hasTagName(trackTag));
67}
68
69HTMLTrackElement::~HTMLTrackElement()
70{
71 if (m_track) {
72 m_track->clearElement();
73 m_track->clearClient();
74 }
75}
76
77Ref<HTMLTrackElement> HTMLTrackElement::create(const QualifiedName& tagName, Document& document)
78{
79 return adoptRef(*new HTMLTrackElement(tagName, document));
80}
81
82Node::InsertedIntoAncestorResult HTMLTrackElement::insertedIntoAncestor(InsertionType insertionType, ContainerNode& parentOfInsertedTree)
83{
84 HTMLElement::insertedIntoAncestor(insertionType, parentOfInsertedTree);
85
86 if (parentNode() == &parentOfInsertedTree && is<HTMLMediaElement>(parentOfInsertedTree)) {
87 downcast<HTMLMediaElement>(parentOfInsertedTree).didAddTextTrack(*this);
88 scheduleLoad();
89 }
90
91 return InsertedIntoAncestorResult::Done;
92}
93
94void HTMLTrackElement::removedFromAncestor(RemovalType removalType, ContainerNode& oldParentOfRemovedTree)
95{
96 HTMLElement::removedFromAncestor(removalType, oldParentOfRemovedTree);
97
98 if (!parentNode() && is<HTMLMediaElement>(oldParentOfRemovedTree))
99 downcast<HTMLMediaElement>(oldParentOfRemovedTree).didRemoveTextTrack(*this);
100}
101
102void HTMLTrackElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
103{
104 if (name == srcAttr) {
105 scheduleLoad();
106
107 // 4.8.10.12.3 Sourcing out-of-band text tracks
108 // As the kind, label, and srclang attributes are set, changed, or removed, the text track must update accordingly...
109 } else if (name == kindAttr)
110 track().setKindKeywordIgnoringASCIICase(value.string());
111 else if (name == labelAttr)
112 track().setLabel(value);
113 else if (name == srclangAttr)
114 track().setLanguage(value);
115 else if (name == defaultAttr)
116 track().setIsDefault(!value.isNull());
117
118 HTMLElement::parseAttribute(name, value);
119}
120
121const AtomicString& HTMLTrackElement::kind()
122{
123 return track().kindKeyword();
124}
125
126void HTMLTrackElement::setKind(const AtomicString& kind)
127{
128 setAttributeWithoutSynchronization(kindAttr, kind);
129}
130
131const AtomicString& HTMLTrackElement::srclang() const
132{
133 return attributeWithoutSynchronization(srclangAttr);
134}
135
136const AtomicString& HTMLTrackElement::label() const
137{
138 return attributeWithoutSynchronization(labelAttr);
139}
140
141bool HTMLTrackElement::isDefault() const
142{
143 return hasAttributeWithoutSynchronization(defaultAttr);
144}
145
146LoadableTextTrack& HTMLTrackElement::track()
147{
148 // FIXME: There is no practical value in lazily initializing this.
149 // Instead this should be created in the constructor.
150 if (!m_track) {
151 // The kind attribute is an enumerated attribute, limited only to known values. It defaults to 'subtitles' if missing or invalid.
152 String kind = attributeWithoutSynchronization(kindAttr).convertToASCIILowercase();
153 if (!TextTrack::isValidKindKeyword(kind))
154 kind = TextTrack::subtitlesKeyword();
155 m_track = LoadableTextTrack::create(*this, kind, label(), srclang());
156 }
157 ASSERT(m_track->trackElement() == this);
158
159 return *m_track;
160}
161
162bool HTMLTrackElement::isURLAttribute(const Attribute& attribute) const
163{
164 return attribute.name() == srcAttr || HTMLElement::isURLAttribute(attribute);
165}
166
167void HTMLTrackElement::scheduleLoad()
168{
169 // 1. If another occurrence of this algorithm is already running for this text track and its track element,
170 // abort these steps, letting that other algorithm take care of this element.
171 if (m_loadTimer.isActive())
172 return;
173
174 // 2. If the text track's text track mode is not set to one of hidden or showing, abort these steps.
175 if (track().mode() != TextTrack::Mode::Hidden && track().mode() != TextTrack::Mode::Showing)
176 return;
177
178 // 3. If the text track's track element does not have a media element as a parent, abort these steps.
179 if (!mediaElement())
180 return;
181
182 // 4. Run the remainder of these steps asynchronously, allowing whatever caused these steps to run to continue.
183 m_loadTimer.startOneShot(0_s);
184}
185
186void HTMLTrackElement::loadTimerFired()
187{
188 if (!hasAttributeWithoutSynchronization(srcAttr)) {
189 track().removeAllCues();
190 return;
191 }
192
193 // 6. Set the text track readiness state to loading.
194 setReadyState(HTMLTrackElement::LOADING);
195
196 // 7. Let URL be the track URL of the track element.
197 URL url = getNonEmptyURLAttribute(srcAttr);
198
199 // ... if URL is the empty string, then queue a task to first change the text track readiness state
200 // to failed to load and then fire an event named error at the track element.
201 // 8. If the track element's parent is a media element then let CORS mode be the state of the parent media
202 // element's crossorigin content attribute. Otherwise, let CORS mode be No CORS.
203 if (url.isEmpty() || !canLoadURL(url)) {
204 track().removeAllCues();
205 didCompleteLoad(HTMLTrackElement::Failure);
206 return;
207 }
208
209 track().scheduleLoad(url);
210}
211
212bool HTMLTrackElement::canLoadURL(const URL& url)
213{
214 auto parent = mediaElement();
215 if (!parent)
216 return false;
217
218 // 4.8.10.12.3 Sourcing out-of-band text tracks
219
220 // 4. Download: If URL is not the empty string, perform a potentially CORS-enabled fetch of URL, with the
221 // mode being the state of the media element's crossorigin content attribute, the origin being the
222 // origin of the media element's Document, and the default origin behaviour set to fail.
223 if (url.isEmpty())
224 return false;
225
226 ASSERT(document().contentSecurityPolicy());
227 // Elements in user agent show tree should load whatever the embedding document policy is.
228 if (!isInUserAgentShadowTree() && !document().contentSecurityPolicy()->allowMediaFromSource(url)) {
229 LOG(Media, "HTMLTrackElement::canLoadURL(%s) -> rejected by Content Security Policy", urlForLoggingTrack(url).utf8().data());
230 return false;
231 }
232
233 return dispatchBeforeLoadEvent(url.string());
234}
235
236void HTMLTrackElement::didCompleteLoad(LoadStatus status)
237{
238 // 4.8.10.12.3 Sourcing out-of-band text tracks (continued)
239
240 // 4. Download: ...
241 // If the fetching algorithm fails for any reason (network error, the server returns an error
242 // code, a cross-origin check fails, etc), or if URL is the empty string or has the wrong origin
243 // as determined by the condition at the start of this step, or if the fetched resource is not in
244 // a supported format, then queue a task to first change the text track readiness state to failed
245 // to load and then fire a simple event named error at the track element; and then, once that task
246 // is queued, move on to the step below labeled monitoring.
247
248 if (status == Failure) {
249 setReadyState(HTMLTrackElement::TRACK_ERROR);
250 dispatchEvent(Event::create(eventNames().errorEvent, Event::CanBubble::No, Event::IsCancelable::No));
251 return;
252 }
253
254 // If the fetching algorithm does not fail, then the final task that is queued by the networking
255 // task source must run the following steps:
256 // 1. Change the text track readiness state to loaded.
257 setReadyState(HTMLTrackElement::LOADED);
258
259 // 2. If the file was successfully processed, fire a simple event named load at the
260 // track element.
261 dispatchEvent(Event::create(eventNames().loadEvent, Event::CanBubble::No, Event::IsCancelable::No));
262}
263
264// NOTE: The values in the TextTrack::ReadinessState enum must stay in sync with those in HTMLTrackElement::ReadyState.
265COMPILE_ASSERT(HTMLTrackElement::NONE == static_cast<HTMLTrackElement::ReadyState>(TextTrack::NotLoaded), TextTrackEnumNotLoaded_Is_Wrong_Should_Be_HTMLTrackElementEnumNONE);
266COMPILE_ASSERT(HTMLTrackElement::LOADING == static_cast<HTMLTrackElement::ReadyState>(TextTrack::Loading), TextTrackEnumLoadingIsWrong_ShouldBe_HTMLTrackElementEnumLOADING);
267COMPILE_ASSERT(HTMLTrackElement::LOADED == static_cast<HTMLTrackElement::ReadyState>(TextTrack::Loaded), TextTrackEnumLoaded_Is_Wrong_Should_Be_HTMLTrackElementEnumLOADED);
268COMPILE_ASSERT(HTMLTrackElement::TRACK_ERROR == static_cast<HTMLTrackElement::ReadyState>(TextTrack::FailedToLoad), TextTrackEnumFailedToLoad_Is_Wrong_Should_Be_HTMLTrackElementEnumTRACK_ERROR);
269
270void HTMLTrackElement::setReadyState(ReadyState state)
271{
272 track().setReadinessState(static_cast<TextTrack::ReadinessState>(state));
273 if (auto parent = mediaElement())
274 parent->textTrackReadyStateChanged(m_track.get());
275}
276
277HTMLTrackElement::ReadyState HTMLTrackElement::readyState()
278{
279 return static_cast<ReadyState>(track().readinessState());
280}
281
282const AtomicString& HTMLTrackElement::mediaElementCrossOriginAttribute() const
283{
284 if (auto parent = mediaElement())
285 return parent->attributeWithoutSynchronization(HTMLNames::crossoriginAttr);
286 return nullAtom();
287}
288
289void HTMLTrackElement::textTrackKindChanged(TextTrack& track)
290{
291 if (auto parent = mediaElement())
292 parent->textTrackKindChanged(track);
293}
294
295void HTMLTrackElement::textTrackModeChanged(TextTrack& track)
296{
297 // Since we've moved to a new parent, we may now be able to load.
298 if (readyState() == HTMLTrackElement::NONE)
299 scheduleLoad();
300
301 if (auto parent = mediaElement())
302 parent->textTrackModeChanged(track);
303}
304
305void HTMLTrackElement::textTrackAddCues(TextTrack& track, const TextTrackCueList& cues)
306{
307 if (auto parent = mediaElement())
308 parent->textTrackAddCues(track, cues);
309}
310
311void HTMLTrackElement::textTrackRemoveCues(TextTrack& track, const TextTrackCueList& cues)
312{
313 if (auto parent = mediaElement())
314 parent->textTrackRemoveCues(track, cues);
315}
316
317void HTMLTrackElement::textTrackAddCue(TextTrack& track, TextTrackCue& cue)
318{
319 if (auto parent = mediaElement())
320 parent->textTrackAddCue(track, cue);
321}
322
323void HTMLTrackElement::textTrackRemoveCue(TextTrack& track, TextTrackCue& cue)
324{
325 if (auto parent = mediaElement())
326 parent->textTrackRemoveCue(track, cue);
327}
328
329RefPtr<HTMLMediaElement> HTMLTrackElement::mediaElement() const
330{
331 auto parent = makeRefPtr(parentElement());
332 if (!is<HTMLMediaElement>(parent))
333 return nullptr;
334 return downcast<HTMLMediaElement>(parent.get());
335}
336
337}
338
339#endif
340