1408722 - Fix sync runnables to return NS_OK and pass result some other way

Status: RESOLVED FIXED

(MailNews Core :: Backend, enhancement)

Description

[Jorg K (CEST = GMT+2)]

While fixing bug 1176748 I noticed that sync runnables must return NS_OK or else the caller will assert here:
https://dxr.mozilla.org/mozilla-central/rev/a31334a65a1c75638efae4452ecd271450df2ad0/xpcom/threads/nsThreadSyncDispatch.h#40
In any case, even in an opt build the error is silently ignored, hey, no one noticed so far :-(

We use sync runnables in four files:
https://dxr.mozilla.org/comm-central/search?q=NS_DISPATCH_SYNC&redirect=false
nsImapProtocol.cpp, nsBeckyMail.cpp, nsImportMail.cpp, mimecms.cpp.

I'm fixing nsImportMail.cpp in bug 1176748 and the one in nsImapProtocol.cpp is already OK. That leaved Becky import and Mime CMS.

Patch coming.

Comment 1

[Jorg K (CEST = GMT+2)]

Attachment: 1408722-sync-runnables.patch (v1)

Comment 2

[:aceman]

Comment on attachment 8918616 [details] [diff] [review]
1408722-sync-runnables.patch (v1)

Review of attachment 8918616 [details] [diff] [review]:
-----------------------------------------------------------------

Thanks, looks reasonable.

Comment 3

[Jorg K (CEST = GMT+2)]

Attachment: 1408722-sync-runnables.patch (v2)

Oops, status of NS_DispatchToMainThread() should be checked, too.

Comment 4

[Jorg K (CEST = GMT+2)]

Here's an example showing "my method" used in M-C, albeit not with a failure result but something else:
http://searchfox.org/mozilla-central/rev/01970ed92d74f82d4e94a1e4365892bbcc593889/widget/windows/WidgetTraceEvent.cpp#79
  NS_DispatchToMainThread(getter, NS_DISPATCH_SYNC);
  return getter->hidden_window_hwnd;

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/af57e5297b94
Fix sync runnables to return NS_OK and pass result differently. r=aceman