Bug 221695 – [GPUP] <audio> won't load when URL ends with .php causing some tests to time out

• Component: Media
• Status: RESOLVED FIXED

[Peng Liu]

http/tests/security/webaudio-render-remote-audio-allowed-crossorigin-redirect.html
http/tests/security/webaudio-render-remote-audio-allowed-crossorigin.html
http/tests/security/webaudio-render-remote-audio-blocked-no-crossorigin-redirect.html
http/tests/security/webaudio-render-remote-audio-blocked-no-crossorigin.html

[Chris Dumez]

May not be a webaudio issue. The HTMLAudioElement.play() promise is getting rejected with:
NotSupportedError: The operation is not supported

[Chris Dumez]

It is hitting this code path in HTMLMediaElement::play():
```
    if (m_error && m_error->code() == MediaError::MEDIA_ERR_SRC_NOT_SUPPORTED) {
        ERROR_LOG(LOGIDENTIFIER, "rejecting promise because of error");
        promise.reject(NotSupportedError, "The operation is not supported.");
        return;
    }
```

[Chris Dumez]

In the GPUProcess, in MediaPlayer::loadWithNextMediaEngine(), nextBestMediaEngine(current) returns null so we end up with m_private being null and lient().mediaPlayerResourceNotSupported() getting called.

m_contentType is {"containerType":"text/php","codecs":"codecs","profiles":"profiles"}

[Chris Dumez]

When the GPUProcess is disabled, nextBestMediaEngine() also returns null in this case. However, we end up calling nextMediaEngine() as fallback and this does return a non-null engine.

So now the question is, why isn't nextMediaEngine() getting called in the GPU Process when nextBestMediaEngine() returns null. May be due to the value for m_contentMIMETypeWasInferredFromExtension being different?

[Chris Dumez]

(In reply to Chris Dumez from comment #4)
> When the GPUProcess is disabled, nextBestMediaEngine() also returns null in
> this case. However, we end up calling nextMediaEngine() as fallback and this
> does return a non-null engine.
> 
> So now the question is, why isn't nextMediaEngine() getting called in the
> GPU Process when nextBestMediaEngine() returns null. May be due to the value
> for m_contentMIMETypeWasInferredFromExtension being different?

m_contentMIMETypeWasInferredFromExtension is indeed true in the WebProcess but false in the GPUProcess, which is why we don't end up calling nextMediaEngine().

When MediaPlayer::load() gets called in the WebProcess, m_contentType.containerType() returns an empty string so we end up setting the m_contentMIMETypeWasInferredFromExtension flag to true. In the GPUProcess though, when MediaPlayer::load() gets called, m_contentType.containerType() returns "text/php" so we don't end up setting the m_contentMIMETypeWasInferredFromExtension flag.

In any case, this is clearly a media issue, not a WebAudio one.

[Chris Dumez]

Basically seems to have regressed Eric's fix in Bug 86308.

[Chris Dumez]

This makes 2 out of the 4 tests pass:
diff --git a/Source/WebCore/platform/graphics/MediaPlayer.cpp b/Source/WebCore/platform/graphics/MediaPlayer.cpp
index 2bc8070055ca..7ecf2d09b085 100644
--- a/Source/WebCore/platform/graphics/MediaPlayer.cpp
+++ b/Source/WebCore/platform/graphics/MediaPlayer.cpp
@@ -577,7 +577,7 @@ void MediaPlayer::loadWithNextMediaEngine(const MediaPlayerFactory* current)
     if (m_private) {
 #if ENABLE(MEDIA_SOURCE)
         if (m_mediaSource)
-            m_private->load(m_url, m_contentType, m_mediaSource.get());
+            m_private->load(m_url, m_contentMIMETypeWasInferredFromExtension ? ContentType() : m_contentType, m_mediaSource.get());
         else
 #endif
 #if ENABLE(MEDIA_STREAM)
@@ -585,7 +585,7 @@ void MediaPlayer::loadWithNextMediaEngine(const MediaPlayerFactory* current)
             m_private->load(*m_mediaStream);
         else
 #endif
-        m_private->load(m_url, m_contentType, m_keySystem);
+        m_private->load(m_url, m_contentMIMETypeWasInferredFromExtension ? ContentType() : m_contentType, m_keySystem);
     } else {
         m_private = makeUnique<NullMediaPlayerPrivate>(this);
         if (!m_activeEngineIdentifier && installedMediaEngines().size() > 1 && nextBestMediaEngine(m_currentMediaEngine))

The other 2 tests (the "allowed" variants) still fail because it seems we are rendering silence. I am not sure if this means the fix is wrong or if there are 2 separate bugs.

[Chris Dumez]

Created attachment 420014 [details]
Patch

[Chris Dumez]

Created attachment 420017 [details]
Patch

[Chris Dumez]

Created attachment 420019 [details]
Patch

[Eric Carlson]

Comment on attachment 420019 [details]
Patch

Nice detective work, thanks!

r=me once the bots are happy

[EWS]

Committed r272750: <https://commits.webkit.org/r272750>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 420019 [details].

[Radar WebKit Bug Importer]

<rdar://problem/74250095>