Changeset 254141 in webkit

Timestamp:

Jan 7, 2020, 11:27:11 AM (7 years ago)

Author:

jer.noble@apple.com

Message:

Flaky API Test: TestWebKitAPI.WebKitLegacy.AudioSessionCategoryIOS
​https://bugs.webkit.org/show_bug.cgi?id=194340
<rdar://problem/50507254>

Reviewed by Eric Carlson.

Workaround for AVFoundation crash for OS versions prior to platform fix. This crash occurrs infrequently
while triggering KVO due to an internal @property change. Work around the crash by disabling KVO for that
property at runtime, by injecting a new class method +automaticallyNotifiesObserversOfSuppressesVideoLayers
immediately after soft linking the AVFoundation library.

• pal/cocoa/AVFoundationSoftLink.mm:

(PAL::justReturnsNO):
(PAL::AVFoundationLibrary):

Location:

trunk/Source/WebCore/PAL

Files:

• ChangeLog (modified) (1 diff)
• pal/cocoa/AVFoundationSoftLink.mm (modified) (1 diff)

trunk/Source/WebCore/PAL/ChangeLog

@@ +1 @@
+2020-01-07  Jer Noble  <jer.noble@apple.com>
+
+        Flaky API Test: TestWebKitAPI.WebKitLegacy.AudioSessionCategoryIOS
+        https://bugs.webkit.org/show_bug.cgi?id=194340
+        <rdar://problem/50507254>
+
+        Reviewed by Eric Carlson.
+
+        Workaround for AVFoundation crash for OS versions prior to platform fix. This crash occurrs infrequently
+        while triggering KVO due to an internal @property change. Work around the crash by disabling KVO for that
+        property at runtime, by injecting a new class method +automaticallyNotifiesObserversOfSuppressesVideoLayers
+        immediately after soft linking the AVFoundation library.
+
+        * pal/cocoa/AVFoundationSoftLink.mm:
+        (PAL::justReturnsNO):
+        (PAL::AVFoundationLibrary):
+
 2020-01-07  Chris Fleizach  <cfleizach@apple.com>
 

trunk/Source/WebCore/PAL/pal/cocoa/AVFoundationSoftLink.mm

@@ -31 +31 @@
 #import <wtf/SoftLinking.h>
 
+#if (PLATFORM(MAC) && __MAC_OS_X_VERSION_MIN_REQUIRED >= 101500) || (PLATFORM(IOS_FAMILY) && __IPHONE_OS_VERSION_MIN_REQUIRED >= 130000)
 SOFT_LINK_FRAMEWORK_FOR_SOURCE_WITH_EXPORT(PAL, AVFoundation, PAL_EXPORT)
+#else
+@interface AVPlayerItem (DisableKVOOnSupressesVideoLayers)
++ (BOOL)automaticallyNotifiesObserversOfSuppressesVideoLayers;
+@end
+
+namespace PAL {
+
+static BOOL justReturnsNO()
+{
+    return NO;
+}
+
+PAL_EXPORT void* AVFoundationLibrary(bool isOptional = false);
+void* AVFoundationLibrary(bool isOptional)
+{
+    static void* frameworkLibrary;
+    static dispatch_once_t once;
+    dispatch_once(&once, ^{
+        frameworkLibrary = dlopen("/System/Library/Frameworks/AVFoundation.framework/AVFoundation", RTLD_NOW);
+        if (!isOptional)
+            RELEASE_ASSERT_WITH_MESSAGE(frameworkLibrary, "%s", dlerror());
+
+        class_addMethod(objc_getClass("AVPlayerItem"), @selector(automaticallyNotifiesObserversOfSuppressesVideoLayers), (IMP)justReturnsNO, "B@:");
+    });
+    return frameworkLibrary;
+}
+
+}
+#endif
 
 SOFT_LINK_CLASS_FOR_SOURCE_WITH_EXPORT(PAL, AVFoundation, AVAssetCache, PAL_EXPORT)