Implement HTMLMediaElement::srcObject.

Source/core/html/HTMLMediaElement.cpp

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 30 matching lines @@
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/frame/UseCounter.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/html/HTMLMediaSource.h"
 #include "core/html/HTMLSourceElement.h"
 #include "core/html/HTMLTrackElement.h"
 #include "core/html/MediaController.h"
 #include "core/html/MediaError.h"
 #include "core/html/MediaFragmentURIParser.h"
+#include "core/html/MediaProvider.h"
 #include "core/html/TimeRanges.h"
 #include "core/html/shadow/MediaControls.h"
 #include "core/html/track/AudioTrack.h"
 #include "core/html/track/AudioTrackList.h"
 #include "core/html/track/InbandTextTrack.h"
 #include "core/html/track/TextTrackCueList.h"
 #include "core/html/track/TextTrackList.h"
 #include "core/html/track/VideoTrack.h"
 #include "core/html/track/VideoTrackList.h"
 #include "core/loader/FrameLoader.h"
@@ skipping 257 matching lines @@
     , m_networkState(NETWORK_EMPTY)
     , m_readyState(HAVE_NOTHING)
     , m_readyStateMaximum(HAVE_NOTHING)
     , m_volume(1.0f)
     , m_lastSeekTime(0)
     , m_previousProgressTime(std::numeric_limits<double>::max())
     , m_duration(std::numeric_limits<double>::quiet_NaN())
     , m_lastTimeUpdateEventWallTime(0)
     , m_defaultPlaybackStartPosition(0)
     , m_loadState(WaitingForSource)
+    , m_srcObject(std::nullptr_t())

[sof, 2014/09/18 07:33:17]

m_srcObject(nullptr)

[perkj_chrome, 2014/09/18 14:47:08]

Done.

     , m_deferredLoadState(NotDeferred)
     , m_deferredLoadTimer(this, &HTMLMediaElement::deferredLoadTimerFired)
     , m_webLayer(0)
     , m_preload(MediaPlayer::Auto)
     , m_displayMode(Unknown)
     , m_cachedTime(MediaPlayer::invalidTime())
     , m_fragmentStartTime(MediaPlayer::invalidTime())
     , m_fragmentEndTime(MediaPlayer::invalidTime())
     , m_pendingActionFlags(0)
     , m_userGestureRequiredForPlay(false)
@@ skipping 334 matching lines @@
     }
 
     m_pendingActionFlags = 0;
 }
 
 PassRefPtrWillBeRawPtr<MediaError> HTMLMediaElement::error() const
 {
     return m_error;
 }
 
+MediaProvider* HTMLMediaElement::srcObject() const
+{
+    return m_srcObject.get();
+}
+
+void HTMLMediaElement::setSrcObject(MediaProvider* mediaProvider)
+{
+    WTF_LOG(Media, "HTMLMediaElement::setSrcObject(%p)", this);
+    m_srcObject = mediaProvider;
+    clearMediaPlayer(LoadMediaResource);
+    load();
+}
+
 void HTMLMediaElement::setSrc(const AtomicString& url)
 {
     setAttribute(srcAttr, url);
 }
 
 HTMLMediaElement::NetworkState HTMLMediaElement::networkState() const
 {
     return m_networkState;
 }
 
@@ skipping 151 matching lines @@
         }
     }
 
     selectMediaResource();
 }
 
 void HTMLMediaElement::selectMediaResource()
 {
     WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p)", this);
 
-    enum Mode { attribute, children };
+    enum Mode { Object, Attribute, Children };
 
-    // 3 - If the media element has a src attribute, then let mode be attribute.
-    Mode mode = attribute;
-    if (!fastHasAttribute(srcAttr)) {
-        // Otherwise, if the media element does not have a src attribute but has a source
-        // element child, then let mode be children and let candidate be the first such
-        // source element child in tree order.
-        if (HTMLSourceElement* element = Traversal<HTMLSourceElement>::firstChild(*this)) {
-            mode = children;
-            m_nextChildNodeToConsider = element;
-            m_currentSourceNode = nullptr;
-        } else {
-            // Otherwise the media element has neither a src attribute nor a source element
-            // child: set the networkState to NETWORK_EMPTY, and abort these steps; the
-            // synchronous section ends.
-            m_loadState = WaitingForSource;
-            setShouldDelayLoadEvent(false);
-            m_networkState = NETWORK_EMPTY;
+    // 6 - If the media element has an assigned media provider object, then let mode be object.
+    Mode mode;
+    if (srcObject()) {
+        mode = Object;
+    } else if (fastHasAttribute(srcAttr)) {
+        // Otherwise, if the media element has no assigned media provider object but has a src attribute, then let mode be attribute.
+        mode = Attribute;
+    } else if (Traversal<HTMLSourceElement>::firstChild(*this)) {
+        // Otherwise, if the media element does not have an assigned media provider object and does not have a src attribute,
+        // but does have a source element child, then let mode be children and let candidate be the first such source element child in tree order.
+        mode = Children;
+        HTMLSourceElement* element = Traversal<HTMLSourceElement>::firstChild(*this);
+        m_nextChildNodeToConsider = element;
+        m_currentSourceNode = nullptr;
+    } else {
+        // Otherwise the media element has no source.
+        // set the networkState to NETWORK_EMPTY, and abort these steps; the
+        // synchronous section ends.
+        m_loadState = WaitingForSource;
+        setShouldDelayLoadEvent(false);
+        m_networkState = NETWORK_EMPTY;
 
-            WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p), nothing to load", this);
-            return;
-        }
+        WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p), nothing to load", this);
+        return;
     }
 
-    // 4 - Set the media element's delaying-the-load-event flag to true (this delays the load event),
+    // 7 - Set the media element's delaying-the-load-event flag to true (this delays the load event),
     // and set its networkState to NETWORK_LOADING.
     setShouldDelayLoadEvent(true);
     m_networkState = NETWORK_LOADING;
 
-    // 5 - Queue a task to fire a simple event named loadstart at the media element.
+    // 8 - Queue a task to fire a simple event named loadstart at the media element.
     scheduleEvent(EventTypeNames::loadstart);
 
-    // 6 - If mode is attribute, then run these substeps
-    if (mode == attribute) {
-        m_loadState = LoadingFromSrcAttr;
+    // 9 - Run the appropriate steps from the following list.
+    switch (mode) {
+    case Object:
+        loadFromObject();
+        break;
+    case Attribute:
+        loadFromAttribute();
+        break;
+    case Children:
+        loadNextSourceChild();
+        break;
+    }
+}
 
-        // If the src attribute's value is the empty string ... jump down to the failed step below
-        KURL mediaURL = getNonEmptyURLAttribute(srcAttr);
-        if (mediaURL.isEmpty()) {
-            mediaLoadingFailed(WebMediaPlayer::NetworkStateFormatError);
-            WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p), empty 'src'", this);
-            return;
-        }
+void HTMLMediaElement::loadFromObject()
+{
+    m_loadState = LoadingFromSrcObject;
 
-        if (!isSafeToLoadURL(mediaURL, Complain)) {
-            mediaLoadingFailed(WebMediaPlayer::NetworkStateFormatError);
-            return;
-        }
+    KURL mediaURL = document().completeURL(m_srcObject->getObjectUrl());
+    ASSERT(isSafeToLoadURL(mediaURL, Complain));
 
-        // No type or key system information is available when the url comes
-        // from the 'src' attribute so MediaPlayer
-        // will have to pick a media engine based on the file extension.
-        ContentType contentType((String()));
-        loadResource(mediaURL, contentType, String());
-        WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p), using 'src' attribute url", this);
+    loadResource(mediaURL);
+
+    // Set the currentSrc attribute to the empty string.
+    // FIXME |m_currentSrc| is set in loadResource and then reset here. The reason is that MediaProviders currently
+    // uses a url for loading, and uses the same algorithm as if the src attribute is set with createObjectURL.
+    m_currentSrc = KURL();
+    WTF_LOG(Media, "HTMLMediaElement::selectMediaResource, using 'srcObject' attribute.");
+    return;
+}
+
+void HTMLMediaElement::loadFromAttribute()
+{
+    m_loadState = LoadingFromSrcAttr;
+
+    // If the src attribute's value is the empty string ... jump down to the failed step below
+    KURL mediaURL = getNonEmptyURLAttribute(srcAttr);
+    if (mediaURL.isEmpty()) {
+        mediaLoadingFailed(WebMediaPlayer::NetworkStateFormatError);
+        WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p), empty 'src'", this);
         return;
     }
 
-    // Otherwise, the source elements will be used
-    loadNextSourceChild();
+    if (!isSafeToLoadURL(mediaURL, Complain)) {
+        mediaLoadingFailed(WebMediaPlayer::NetworkStateFormatError);
+        return;
+    }
+
+    loadResource(mediaURL);
+    WTF_LOG(Media, "HTMLMediaElement::selectMediaResource(%p), using 'src' attribute url", this);
+    return;
 }
 
 void HTMLMediaElement::loadNextSourceChild()
 {
     ContentType contentType((String()));
     String keySystem;
     KURL mediaURL = selectNextSourceChild(&contentType, &keySystem, Complain);
     if (!mediaURL.isValid()) {
         waitForSourceChange();
         return;
     }
 
     // Recreate the media player for the new url
     createMediaPlayer();
 
     m_loadState = LoadingFromSourceElement;
     loadResource(mediaURL, contentType, keySystem);
 }
 
+void HTMLMediaElement::loadResource(const KURL& url)
+{
+    // No type or key system information is available when the url comes
+    // from the 'src' attribute or a srcObject.
+    ContentType contentType((String()));

[sof, 2014/09/18 07:33:17]

redundant ()

[perkj_chrome, 2014/09/18 14:47:08]

This does not compile without the extra parenthesis.
ContentType(const String& contentType)

Also see loadNextSourceChild().

[sof, 2014/09/19 06:26:23]

Oh, I see. Why not use emptyString?

+    loadResource(url, contentType, String());
+}
+
 void HTMLMediaElement::loadResource(const KURL& url, ContentType& contentType, const String& keySystem)
 {
     ASSERT(isSafeToLoadURL(url, Complain));
 
     WTF_LOG(Media, "HTMLMediaElement::loadResource(%p, %s, %s, %s)", this, urlForLoggingMedia(url).utf8().data(), contentType.raw().utf8().data(), keySystem.utf8().data());
 
     LocalFrame* frame = document().frame();
     if (!frame) {
         mediaLoadingFailed(WebMediaPlayer::NetworkStateFormatError);
         return;
@@ skipping 2981 matching lines @@
             mediaControls()->mediaElementFocused();
     }
     HTMLElement::defaultEventHandler(event);
 }
 
 void HTMLMediaElement::trace(Visitor* visitor)
 {
     visitor->trace(m_playedTimeRanges);
     visitor->trace(m_asyncEventQueue);
     visitor->trace(m_error);
     visitor->trace(m_currentSourceNode);

[sof, 2014/09/18 07:33:17]

Fields that refer to objects that are on the Oilpan heap needs to be traced
during a garbage collection, so as to keep them alive. So, whenever you add a
Member<T> (via the transition type RawPtrWillBeMember<T> right now), you need to
extend trace() accordingly. So, add

   visitor->trace(m_srvObject);

right here.

[perkj_chrome, 2014/09/18 14:47:08]

oops, right- thanks.

     visitor->trace(m_nextChildNodeToConsider);
     visitor->trace(m_mediaSource);
     visitor->trace(m_audioTracks);
     visitor->trace(m_videoTracks);
     visitor->trace(m_textTracks);
     visitor->trace(m_textTracksWhenResourceSelectionBegan);
     visitor->trace(m_mediaController);
 #if ENABLE(WEB_AUDIO)
     visitor->registerWeakMembers<HTMLMediaElement, &HTMLMediaElement::clearWeakMembers>(this);
 #endif
@@ skipping 31 matching lines @@
 
 #if ENABLE(WEB_AUDIO)
 void HTMLMediaElement::clearWeakMembers(Visitor* visitor)
 {
     if (!visitor->isAlive(m_audioSourceNode) && audioSourceProvider())
         audioSourceProvider()->setClient(0);
 }
 #endif
 
 }