Bug 178713 – [iOS] MediaPlayer::isAvailable() takes ~150 ms during web process initialization

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Wenson Hsieh]

<rdar://problem/35115906>

[Wenson Hsieh]

Created attachment 324651 [details]
Patch

[Eric Carlson]

Comment on attachment 324651 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=324651&action=review

> Source/WebCore/platform/graphics/MediaPlayer.cpp:961
> +#if USE(AVFOUNDATION)
> +    if (DeprecatedGlobalSettings::isAVFoundationEnabled())
> +        return true;
> +#endif

The AVFoundation and CoreMedia frameworks are not installed on a recovery partition, so this will cause HTMLMediaElement to be in the DOM but MediaPlayerPrivateAVFoundationObjC::registerMediaEngine will fail so <audio> and <video> elements won't work. You might make MediaPlayerPrivateAVFoundationObjC::isAvailable() public and call it here instead.

[Wenson Hsieh]

(In reply to Eric Carlson from comment #2)
> Comment on attachment 324651 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=324651&action=review
> 
> > Source/WebCore/platform/graphics/MediaPlayer.cpp:961
> > +#if USE(AVFOUNDATION)
> > +    if (DeprecatedGlobalSettings::isAVFoundationEnabled())
> > +        return true;
> > +#endif
> 
> The AVFoundation and CoreMedia frameworks are not installed on a recovery
> partition, so this will cause HTMLMediaElement to be in the DOM but
> MediaPlayerPrivateAVFoundationObjC::registerMediaEngine will fail so <audio>
> and <video> elements won't work. You might make
> MediaPlayerPrivateAVFoundationObjC::isAvailable() public and call it here
> instead.

Ah, ok...I suspected there might be a case where this would fail :/

My goal is to avoid invoking MediaPlayerPrivateAVFoundationObjC::isAvailable() altogether, since that tries to dlopen() AVFoundation...I'll see if there's another way to address this. Thanks!

[Wenson Hsieh]

(In reply to Wenson Hsieh from comment #3)
> (In reply to Eric Carlson from comment #2)
> > Comment on attachment 324651 [details]
> > Patch
> > 
> > View in context:
> > https://bugs.webkit.org/attachment.cgi?id=324651&action=review
> > 
> > > Source/WebCore/platform/graphics/MediaPlayer.cpp:961
> > > +#if USE(AVFOUNDATION)
> > > +    if (DeprecatedGlobalSettings::isAVFoundationEnabled())
> > > +        return true;
> > > +#endif
> > 
> > The AVFoundation and CoreMedia frameworks are not installed on a recovery
> > partition, so this will cause HTMLMediaElement to be in the DOM but
> > MediaPlayerPrivateAVFoundationObjC::registerMediaEngine will fail so <audio>
> > and <video> elements won't work. You might make
> > MediaPlayerPrivateAVFoundationObjC::isAvailable() public and call it here
> > instead.
> 
> Ah, ok...I suspected there might be a case where this would fail :/
> 
> My goal is to avoid invoking
> MediaPlayerPrivateAVFoundationObjC::isAvailable() altogether, since that
> tries to dlopen() AVFoundation...I'll see if there's another way to address
> this. Thanks!

Spoke to Eric in person -- while AVFoundation and CoreMedia may not exist in recovery partitions, this is only the case on Mac. On iOS, it is generally safe to assume that AVFoundation and CoreMedia exist (otherwise, many other system apps and frameworks would fail anyways). Since this early return is desired for improving performance on iOS-based platforms in the first place, we can just guard it with PLATFORM(IOS).

[Wenson Hsieh]

Created attachment 324679 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 324679 [details]
Patch

Clearing flags on attachment: 324679

Committed r223897: <https://trac.webkit.org/changeset/223897>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.