297862 - Provide an API to restart the application

Status: RESOLVED FIXED

(Toolkit :: Startup and Profile System, enhancement)

Description

[Darin Fisher]

Provide an API to restart the application

I suspect that this involves adding an API to nsIXULRuntime to "schedule" a
restart to happen when nsAppRunner.cpp is shutting down.  Then, someone
interested in restarting the application would use nsICloseAllWindows to cause
the application to shutdown.

Comment 1

[Darin Fisher]

This approach basically involves finding a way to set needsRestart to TRUE in
nsAppRunner.cpp and setting a flag to cause it to avoid checking the
NO_EM_RESTART environment variable.

Comment 2

[Benjamin Smedberg]

What's the use-case? I've thought about this several times before (my original
spec for nsICommandLine actually had a restart flag), but I haven't discovered
any uses for it.

Comment 3

[James Ross]

I would assume the use-case is the new update stuff, which probably wants to
actually be user friendly and offer to restart the app for the user (except
it'll lose everything they're doing, which I hope it will mention, and wont
force anyone into it ;) ). I can't think that anything else would need it, though.

Comment 4

[Darin Fisher]

bsmedberg: The use case is the update system.  Ben wants to be able to offer to
apply an available software update "now," which in the new system means
restarting the app.

Comment 5

[Darin Fisher]

I think that Ben also wants extension manager to present the user with similar
UI after they make a change that requires a restart.

Comment 6

[Benjamin Smedberg]

OK, makes sense. I'm cautious about the "avoid checking the NO_EM_RESTART" bit:
we should make sure that our tinderbox test builds don't end up doing this restart.

Regarding the impl, I don't think you need to use the closeallwindows impl
yourself (which doesn't do what you expect on mac), and I don't think we should
attach this to nsIXULRuntime; instead, modify nsIAppStartup.quit with an extra
"restart" flag, and use it directly. It will call the closeallwindows impl in
the appropriate situations. You can pass a result code or a PRBool flag from
nsIAppStartup.run() back to nsAppRunner.

Finally, I think you should use the eAttemptQuit version instead of eForceQuit
for both software update and EM "restart now": that way people won't
accidentally lose work-in-progress if they click "cancel" on one of the
"download in progress" or "multiple tabs open" dialogs.

Comment 7

[Darin Fisher]

Sounds reasonable.  If closeallwindows is not what I want on Mac, then what is?

By the way, I believe that NO_EM_RESTART is actually not an issue since we clear
NO_EM_RESTART once we load the application for real ;-) 

Comment 8

[Benjamin Smedberg]

nsIAppStartup.quit will clean up windows for you (either with warning dialogs
for eAttemptQuit or without for eForceQuit), you don't need to mess with that
manually at all.

Comment 9

[Darin Fisher]

Attachment: v1 patch

Comment 10

[Benjamin Smedberg]

Comment on attachment 186646 [details] [diff] [review]
v1 patch

Remember to remove extraneous printf (nsAppStartup::Quit).

I also thought that gSavedVars was supposed to have XRE_PROFILE_PATH and
LOCAL_PROFILE_PATH.

Comment 11

[Darin Fisher]

(In reply to comment #10)
> (From update of attachment 186646 [details] [diff] [review] [edit])
> Remember to remove extraneous printf (nsAppStartup::Quit).

Yes :)


> I also thought that gSavedVars was supposed to have XRE_PROFILE_PATH and
> LOCAL_PROFILE_PATH.

I thought so too, until I realized that we set those env vars when we restart
the app from the bottom of XRE_Main.  So there is no reason to set them twice.

Comment 12

[Darin Fisher]

Comment on attachment 186646 [details] [diff] [review]
v1 patch

This is needed by the new software update system.

Comment 13

[Darin Fisher]

fixed-on-trunk

Comment 14

[Henrik Gemal]

With this fixed now would it be possible to add a button to restart Firefox
after you install an extension? Perhaps a restart extension?

Comment 15

[Benjamin Smedberg]

Henrik: that is the plan, yes.

Comment 16

[Steve Russell (RaiseMachine)]

(In reply to comment #14)
> With this fixed now would it be possible to add a button to restart Firefox
> after you install an extension? Perhaps a restart extension?

Done by jedbro.
http://forums.mozillazine.org/viewtopic.php?t=319438

Comment 17

[Mel Reyes]

One nice feature would be to be able to pass a command line param on restart for
example to create a mock Profile Manager or to restart in Safe Mode, etc.  Thanks.

Comment 18

[Darin Fisher]

(In reply to comment #17)
> One nice feature would be to be able to pass a command line param on restart for
> example to create a mock Profile Manager or to restart in Safe Mode, etc.  Thanks.

Agreed.  Please file a new bug for that.  I don't expect it to be fixed in time
for 1.5 though :(

Comment 19

[Mel Reyes]

Submitted Command-Line Request here
https://bugzilla.mozilla.org/show_bug.cgi?id=310378