Bug 32827 – Crash when calling IWebView::close, then releasing the WebView, without calling DestroyWindow

• Component: WebKit API
• Status: RESOLVED FIXED

[Adam Roben (:aroben)]

Created attachment 45337 [details]
Patch

WebKit clients can currently cleanly get rid of a WebView in two ways.
A)
1) DestroyWindow(webViewHWND)
2) webView->Release()
B)
1) webView->close()
2) DestroyWindow(webViewHWND) (can be swapped with (1))
3) webView->Release()

We'd like clients to be able to get rid of a WebView just by releasing
the last reference to it. This patch gets us a little closer to that
by removing step B2 above (though calling DestroyWindow in this case
is harmless). A future patch will make steps A1 and B1 unnecessary, as
well.

Fixes <rdar://problem/7374218> Crash in WebView::updateActiveState
when closing "Welcome to iTunes" window

Reviewed by NOBODY (OOPS!).

* WebView.cpp:
(WebView::~WebView): Call setIsBeingDestroyed() so that we won't be
ref'd by our WndProc, which would result in this destructor being
re-entered.
(WebView::close): Moved the call to revokeDragDrop here...
(WebView::WebViewWndProc): ...from here. This is important in order to
release the reference that OLE holds while we're registered as a drop
target. Otherwise, clients that call IWebView::close but not
DestroyWindow would leak the WebView.

* WebView.h:
(WebView::setIsBeingDestroyed):
(WebView::isBeingDestroyed):
Made these private, and added a comment about what isBeingDestroyed()
now means.
---
 3 files changed, 52 insertions(+), 5 deletions(-)

[Adam Roben (:aroben)]

<rdar://problem/7374218>

[WebKit Review Bot]

style-queue ran check-webkit-style on attachment 45337 [details] without any errors.

[Adam Roben (:aroben)]

Comment on attachment 45337 [details]
Patch

I'm going to try tackling this a different way.

[Adam Roben (:aroben)]

Created attachment 45912 [details]
Make it safe to call IWebView::close when IWebView::initWithFrame hasn't been called

[WebKit Review Bot]

style-queue ran check-webkit-style on attachment 45912 [details] without any errors.

[Adam Roben (:aroben)]

Created attachment 45916 [details]
Make IWebView::close and destroying a WebView's HWND optional for WebKit clients

[Eric Seidel (no email)]

Comment on attachment 45912 [details]
Make it safe to call IWebView::close when IWebView::initWithFrame hasn't been called

Looks sane to me too.

[Adam Roben (:aroben)]

Committed r52829: <http://trac.webkit.org/changeset/52829>

[Adam Roben (:aroben)]

Committed r52830: <http://trac.webkit.org/changeset/52830>