Bug 194086 – [GLIB] WebDriver: race condition when session starts

• Status: RESOLVED
• Resolution: FIXED
• Component: WebDriver

[Carlos Garcia Campos]

This is causing flakiness in WebDriver bots, I can only reproduce it locally when my CPUs are at 100%. The thing is that sometimes we receive an empty target list right after the connection is established because RemoteInspector::setClient() calls pushListingsSoon() before a target has been registered. Most of the times the target is registered before the listing is pushed, but it can happen that when pushed the listing is still empty. After the target is registered an empty target list means the connection was lost, so we clear the connection and target. We need to ensure we do that only after the target has been registered.

[Carlos Garcia Campos]

Created attachment 360716 [details]
Patch

[Philippe Normand]

Comment on attachment 360716 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=360716&action=review

> Source/WebDriver/glib/SessionHostGlib.cpp:335
>          m_connectionID = 0;
> -        if (m_dbusConnection)
> +        if (m_connectionID && m_dbusConnection)

So now this condition is always false because m_connectionID is set to 0 before the if. Is this correct? Why not remove the if block then?

[Carlos Garcia Campos]

(In reply to Philippe Normand from comment #2)
> Comment on attachment 360716 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=360716&action=review
> 
> > Source/WebDriver/glib/SessionHostGlib.cpp:335
> >          m_connectionID = 0;
> > -        if (m_dbusConnection)
> > +        if (m_connectionID && m_dbusConnection)
> 
> So now this condition is always false because m_connectionID is set to 0
> before the if. Is this correct? Why not remove the if block then?

Oops, you are right!

[Carlos Garcia Campos]

Created attachment 360717 [details]
Updated patch

[Carlos Garcia Campos]

Committed r240778: <https://trac.webkit.org/changeset/240778>

[Radar WebKit Bug Importer]

<rdar://problem/47699722>