Seeking media fragment URI before loadeddata event

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 337 matching lines @@
     , m_seeking(false)
     , m_sentStalledEvent(false)
     , m_sentEndEvent(false)
     , m_pausedInternal(false)
     , m_closedCaptionsVisible(false)
     , m_completelyLoaded(false)
     , m_havePreparedToPlay(false)
     , m_tracksAreReady(true)
     , m_haveVisibleTextTrack(false)
     , m_processingPreferenceChange(false)
+    , m_jumped(false)
 #if ENABLE(OILPAN)
     , m_isFinalizing(false)
     , m_closeMediaSourceWhenFinalizing(false)
 #endif
     , m_lastTextTrackUpdateTime(-1)
     , m_audioTracks(AudioTrackList::create(*this))
     , m_videoTracks(VideoTrackList::create(*this))
     , m_textTracks(nullptr)
     , m_ignoreTrackDisplayUpdate(0)
 #if ENABLE(WEB_AUDIO)
@@ skipping 1449 matching lines @@
 
         selectInitialTracksIfNecessary();
 
         m_duration = duration();
         scheduleEvent(EventTypeNames::durationchange);
 
         if (isHTMLVideoElement())
             scheduleEvent(EventTypeNames::resize);
         scheduleEvent(EventTypeNames::loadedmetadata);
 
+        m_jumped = false;
         if (m_defaultPlaybackStartPosition > 0) {
             seek(m_defaultPlaybackStartPosition);
+            m_jumped = true;
             m_defaultPlaybackStartPosition = 0;
         }
 
         if (hasMediaControls())
             mediaControls()->reset();
         if (renderer())
             renderer()->updateFromElement();
     }
 
     bool shouldUpdateDisplayState = false;
 
     if (m_readyState >= HAVE_CURRENT_DATA && oldState < HAVE_CURRENT_DATA && !m_haveFiredLoadedData) {
         m_haveFiredLoadedData = true;
         shouldUpdateDisplayState = true;
         scheduleEvent(EventTypeNames::loadeddata);
         setShouldDelayLoadEvent(false);
-        applyMediaFragmentURI();
+        if (!m_jumped)
+            applyMediaFragmentURI();

[amogh.bihani, 2014/09/04 13:44:18]

Could you help me understand why this is here? I mean in the spec this is step
10, before loadeddata event. If we move this up then it would be easy to remove
m_fragmentStartTime as well, otherwise I guess it is better to evaluate it
before hand when we evalute m_fragmentEndtime in prepareMediaFragmentURI.

[philipj_slow, 2014/09/04 13:46:45]

Sorry, I didn't see this comment at first. You're right, we shouldn't have a
split prepareMediaFragmentURI() and applyMediaFragmentURI(), it should all go in
a single place.

     }
 
     bool isPotentiallyPlaying = potentiallyPlaying();
     if (m_readyState == HAVE_FUTURE_DATA && oldState <= HAVE_CURRENT_DATA && tracksAreReady) {
         scheduleEvent(EventTypeNames::canplay);
         if (isPotentiallyPlaying)
             scheduleEvent(EventTypeNames::playing);
         shouldUpdateDisplayState = true;
     }
 
@@ skipping 2035 matching lines @@
         m_fragmentEndTime = MediaPlayer::invalidTime();
 
     // FIXME: Add support for selecting tracks by ID with the Media Fragments track dimension.
 
     if (m_fragmentStartTime != MediaPlayer::invalidTime() && m_readyState < HAVE_FUTURE_DATA)
         prepareToPlay();
 }
 
 void HTMLMediaElement::applyMediaFragmentURI()
 {
+    ASSERT(!m_jumped);
+
     if (m_fragmentStartTime != MediaPlayer::invalidTime()) {
         m_sentEndEvent = false;
         UseCounter::count(document(), UseCounter::HTMLMediaElementSeekToFragmentStart);
         seek(m_fragmentStartTime);
+        m_jumped = true;
     }
 }
 
 WebMediaPlayer::CORSMode HTMLMediaElement::corsMode() const
 {
     const AtomicString& crossOriginMode = fastGetAttribute(crossoriginAttr);
     if (crossOriginMode.isNull())
         return WebMediaPlayer::CORSModeUnspecified;
     if (equalIgnoringCase(crossOriginMode, "use-credentials"))
         return WebMediaPlayer::CORSModeUseCredentials;
@@ skipping 86 matching lines @@
 
 #if ENABLE(WEB_AUDIO)
 void HTMLMediaElement::clearWeakMembers(Visitor* visitor)
 {
     if (!visitor->isAlive(m_audioSourceNode) && audioSourceProvider())
         audioSourceProvider()->setClient(0);
 }
 #endif
 
 }