1231586 - ServiceWorkerManager singleton is cleared too late during shutdown

Status: RESOLVED WONTFIX

(Core :: DOM: Service Workers, defect)

Description

[Ben Kelly [:bkelly, not reviewing]]

Currently ServiceWorkerManager uses ClearOnShutdown() to drop its singleton reference.  This occurs around "XPCOM Component Shutdown" in this table:

  https://wiki.mozilla.org/XPCOM_Shutdown

Thats pretty late in the process.

The SWM, however, does a bunch of cleanup much earlier at "xpcom-shutdown".

It seems this leaves a window during shutdown where a reference to the SWM can still be found, but the SWM is not in a fully initialized state.

We should either clear the SWM singleton ref at xpcom-shutdown time or check mShuttingDown in GetInstance.

Comment 1

[Ben Kelly [:bkelly, not reviewing]]

I guess keeping the ref might be necessary for clearing events through shutdown.  Maybe the mShuttingDown variable is the way to handle this.

I'm going to leave this bug open for now, but not actively work on a patch.

Comment 2

[Ben Kelly [:bkelly, not reviewing]]

Yea, mShuttingDown is the way to go.  Sorry for the noise here.