Changeset 170988 in webkit

Timestamp:

Jul 10, 2014, 7:29:33 PM (11 years ago)

Author:

benjamin@webkit.org

Message:

[iOS][WK2] It should be safe to call WKContentViewInteraction's cleanupInteraction multiple times
​https://bugs.webkit.org/show_bug.cgi?id=134820

Patch by Benjamin Poulain <​bpoulain@apple.com> on 2014-07-10
Reviewed by Andreas Kling.

If a view is destroyed just after a crash, "cleanupInteraction" is called twice: once on crash,
once on dealloc.

The code handling _interactionViewsContainerView is using KVO to monitor transform changes. It is not safe
to remove the observer if we are not already observing on that view.

To solve the problem, this patch makes the cleanup actually remove the view so that setup and cleanup
are completely symmetrical. If cleanup is called twice, the second time would not enter the branch because
the view is already nil.

• UIProcess/ios/WKContentViewInteraction.mm:

(-[WKContentView setupInteraction]):
(-[WKContentView cleanupInteraction]):

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• UIProcess/ios/WKContentViewInteraction.mm (modified) (2 diffs)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2014-07-10  Benjamin Poulain  <bpoulain@apple.com>
+
+        [iOS][WK2] It should be safe to call WKContentViewInteraction's cleanupInteraction multiple times
+        https://bugs.webkit.org/show_bug.cgi?id=134820
+
+        Reviewed by Andreas Kling.
+
+        If a view is destroyed just after a crash, "cleanupInteraction" is called twice: once on crash,
+        once on dealloc.
+
+        The code handling _interactionViewsContainerView is using KVO to monitor transform changes. It is not safe
+        to remove the observer if we are not already observing on that view.
+
+        To solve the problem, this patch makes the cleanup actually remove the view so that setup and cleanup
+        are completely symmetrical. If cleanup is called twice, the second time would not enter the branch because
+        the view is already nil.
+
+        * UIProcess/ios/WKContentViewInteraction.mm:
+        (-[WKContentView setupInteraction]):
+        (-[WKContentView cleanupInteraction]):
+
 2014-07-10  Simon Fraser  <simon.fraser@apple.com>
 

trunk/Source/WebKit2/UIProcess/ios/WKContentViewInteraction.mm

@@ -221 +221 @@
         [_interactionViewsContainerView setOpaque:NO];
         [_interactionViewsContainerView layer].anchorPoint = CGPointZero;
-    }
-    [_interactionViewsContainerView setHidden:NO];
+        [self.superview addSubview:_interactionViewsContainerView.get()];
+    }
+
     [self.layer addObserver:self forKeyPath:@"transform" options:NSKeyValueObservingOptionInitial context:nil];
 
@@ -277 +278 @@
     _formInputSession = nil;
     [_highlightView removeFromSuperview];
-    [self.layer removeObserver:self forKeyPath:@"transform"];
-    [_interactionViewsContainerView setHidden:YES];
+
+    if (_interactionViewsContainerView) {
+        [self.layer removeObserver:self forKeyPath:@"transform"];
+        [_interactionViewsContainerView removeFromSuperview];
+        _interactionViewsContainerView = nil;
+    }
+
     [_touchEventGestureRecognizer setDelegate:nil];
     [self removeGestureRecognizer:_touchEventGestureRecognizer.get()];