Changeset 25777 in webkit

Timestamp:

Sep 27, 2007, 2:24:26 PM (18 years ago)

Author:

thatcher

Message:

Reviewed by Darin.

<rdar://problem/5199546> CrashTracer: [REGRESSION] 8216 crashes in Safari at com.apple.WebCore: WebCore::ResourceHandle::client const + 6

On Tiger CFURLConnection can sometimes call the connection:willCacheResponse: delegate method on
a secondary thread instead of the main thread. This was never an issue before, since the implementation
of this method was very simple and thread safe.

The fix is to block during connection:willCacheResponse: and perform the work on the main thread.
We need to block since this delegate method needs to return a result. If we are already on the
main thread (which sometimes we are), the method does nothing different. If we are on a secondary
thread, we make a mutable dictionary to hold all the arguments and later the result object.
Then performSelectorOnMainThread:withObject: using the _callConnectionWillCacheResponseWithInfo:
selector. This new method just pulls the arguments out for the dictionary and calls the real
connection:willCacheResponse: delegate method (this time on the main thread). The result is stored
in the dictionary, and when performSelectorOnMainThread:withObject: finishes the result is pulled
out and returned.

• platform/network/mac/ResourceHandleMac.mm: (-[WebCoreResourceHandleAsDelegate _callConnectionWillCacheResponseWithInfo:]): (-[WebCoreResourceHandleAsDelegate connection:willCacheResponse:]):

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/network/mac/ResourceHandleMac.mm (modified) (1 diff)

trunk/WebCore/ChangeLog

@@ +1 @@
+2007-09-27  Timothy Hatcher  <timothy@apple.com>
+
+        Reviewed by Darin.
+
+        <rdar://problem/5199546> CrashTracer: [REGRESSION] 8216 crashes in Safari at com.apple.WebCore: WebCore::ResourceHandle::client const + 6
+
+        On Tiger CFURLConnection can sometimes call the connection:willCacheResponse: delegate method on
+        a secondary thread instead of the main thread. This was never an issue before, since the implementation 
+        of this method was very simple and thread safe.
+
+        The fix is to block during connection:willCacheResponse: and perform the work on the main thread.
+        We need to block since this delegate method needs to return a result. If we are already on the
+        main thread (which sometimes we are), the method does nothing different. If we are on a secondary
+        thread, we make a mutable dictionary to hold all the arguments and later the result object.
+        Then performSelectorOnMainThread:withObject: using the _callConnectionWillCacheResponseWithInfo:
+        selector. This new method just pulls the arguments out for the dictionary and calls the real
+        connection:willCacheResponse: delegate method (this time on the main thread). The result is stored
+        in the dictionary, and when performSelectorOnMainThread:withObject: finishes the result is pulled
+        out and returned.
+
+        * platform/network/mac/ResourceHandleMac.mm:
+        (-[WebCoreResourceHandleAsDelegate _callConnectionWillCacheResponseWithInfo:]):
+        (-[WebCoreResourceHandleAsDelegate connection:willCacheResponse:]):
+
 2007-09-27  David Hyatt  <hyatt@apple.com>
 

trunk/WebCore/platform/network/mac/ResourceHandleMac.mm

@@ -466 +466 @@
 }
 
+#ifdef BUILDING_ON_TIGER
+- (void)_callConnectionWillCacheResponseWithInfo:(NSMutableDictionary *)info
+{
+    NSURLConnection *connection = [info objectForKey:@"connection"];
+    NSCachedURLResponse *cachedResponse = [info objectForKey:@"cachedResponse"];
+    NSCachedURLResponse *result = [self connection:connection willCacheResponse:cachedResponse];
+    if (result)
+        [info setObject:result forKey:@"result"];
+}
+#endif
+
 - (NSCachedURLResponse *)connection:(NSURLConnection *)connection willCacheResponse:(NSCachedURLResponse *)cachedResponse
 {
+#ifdef BUILDING_ON_TIGER
+    // On Tiger CFURLConnection can sometimes call the connection:willCacheResponse: delegate method on
+    // a secondary thread instead of the main thread. If this happens perform the work on the main thread.
+    if (!pthread_main_np()) {
+        NSMutableDictionary *info = [[NSMutableDictionary alloc] init];
+        if (connection)
+            [info setObject:connection forKey:@"connection"];
+        if (cachedResponse)
+            [info setObject:cachedResponse forKey:@"cachedResponse"];
+
+        [self performSelectorOnMainThread:@selector(_callConnectionWillCacheResponseWithInfo:) withObject:info waitUntilDone:YES];
+
+        NSCachedURLResponse *result = [[info valueForKey:@"result"] retain];
+        [info release];
+
+        return [result autorelease];
+    }
+#endif
+
 #ifndef NDEBUG
     if (isInitializingConnection)