509046 - Gtk embedding code locks up when a modal window is created, and doesn't handle chrome windows correctly

Status: RESOLVED WONTFIX

(Core Graveyard :: Embedding: GTK Widget, defect)

Description

[Chris Lord [:cwiiis]]

User-Agent:       Mozilla/5.0 (X11; U; Linux x86_64; en-GB; rv:1.9.1.2) Gecko/20090803 Fedora/3.5.2-2.fc11 Firefox/3.5.2
Build Identifier: 

If you disable the nsIPromptService for gtkmozembed and you cause a modal window to be created, the process will lock up and have to be killed.

Further to this, chrome windows aren't handled correctly (window item type is always set as content, regardless of the chromeflags sent to the WindowCreator). If you fix the lock-up, you will then notice that all dialogs appear as empty with non-working OK/Cancel buttons (for the most-part).

I encountered these bugs while writing the headless backend and was guided through fixing them on Mozilla IRC - attached is a patch that back-ports these fixes to the gtk backend.

Note that ABI is preserved, but a new API call is added that is required if the user wants chrome dialogs to work correctly.

Reproducible: Always

Steps to Reproduce:
Reproducing without disabling the PromptService is hard, but there's a further bug that causes components to be de-registered it seems, so users of Epiphany (the Gnome web browser) would occasionally encounter this.

Although the first bug should be fixed, tracking that down is much harder (as it's intermittent), so this patch should at least stop the process from locking up and allow continuation and safe shut-down (possibly).

If you disable the the PromptService in the gtk embedding code though, just go to the url 'javascript:alert("Hello")'.
Actual Results:  
It locks the embedding process (note, it hasn't locked, it just stops responding to input).

Expected Results:  
I'd expect the above to launch a window with the text 'Hello', etc., as you'd expect, without locking up.

It locks up because EmbedWindow::ShowModal calls 'gtk_main', which then proceeds to sit there and do nothing. The attached patch replaces this part by spinning the mozilla mainloop instead, similar to xulrunner.

Comment 1

[Chris Lord [:cwiiis]]

Attachment: Patch that fixes modal windows and chrome windows in gtkmozembed

Comment 2

[Sylvestre Ledru [:Sylvestre]]

Embedding: GTK Widget isn't a thing, closing.