Avoid crashing on non-fatal Objective-C exceptions caused by a 10.4-only Apple bug. b=461381 r=josh sr=roc

widget/src/cocoa/nsMenuX.mm

@@ -88,14 +88,19 @@ nsMenuX::nsMenuX()
 {
   NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
 
-  if (nsToolkit::OnLeopardOrLater() && !gMenuMethodsSwizzled) {
-    nsToolkit::SwizzleMethods([NSMenu class], @selector(_addItem:toTable:),
-                              @selector(nsMenuX_NSMenu_addItem:toTable:), PR_TRUE);
-    nsToolkit::SwizzleMethods([NSMenu class], @selector(_removeItem:fromTable:),
-                              @selector(nsMenuX_NSMenu_removeItem:fromTable:), PR_TRUE);
-    Class SCTGRLIndexClass = ::NSClassFromString(@"SCTGRLIndex");
-    nsToolkit::SwizzleMethods(SCTGRLIndexClass, @selector(indexMenuBarDynamically),
-                              @selector(nsMenuX_SCTGRLIndex_indexMenuBarDynamically));
+  if (!gMenuMethodsSwizzled) {
+    if (nsToolkit::OnLeopardOrLater()) {
+      nsToolkit::SwizzleMethods([NSMenu class], @selector(_addItem:toTable:),
+                                @selector(nsMenuX_NSMenu_addItem:toTable:), PR_TRUE);
+      nsToolkit::SwizzleMethods([NSMenu class], @selector(_removeItem:fromTable:),
+                                @selector(nsMenuX_NSMenu_removeItem:fromTable:), PR_TRUE);
+      Class SCTGRLIndexClass = ::NSClassFromString(@"SCTGRLIndex");
+      nsToolkit::SwizzleMethods(SCTGRLIndexClass, @selector(indexMenuBarDynamically),
+                                @selector(nsMenuX_SCTGRLIndex_indexMenuBarDynamically));
+    } else {
+      nsToolkit::SwizzleMethods([NSMenu class], @selector(performKeyEquivalent:),
+                                @selector(nsMenuX_NSMenu_performKeyEquivalent:));
+    }
     gMenuMethodsSwizzled = PR_TRUE;
   }
 
@@ -1120,6 +1125,7 @@ static NSMutableDictionary *gShadowKeyEquivDB = nil;
 @interface NSMenu (MethodSwizzling)
 + (void)nsMenuX_NSMenu_addItem:(NSMenuItem *)aItem toTable:(NSMapTable *)aTable;
 + (void)nsMenuX_NSMenu_removeItem:(NSMenuItem *)aItem fromTable:(NSMapTable *)aTable;
+- (BOOL)nsMenuX_NSMenu_performKeyEquivalent:(NSEvent *)theEvent;
 @end
 
 @implementation NSMenu (MethodSwizzling)
@@ -1165,6 +1171,20 @@ static NSMutableDictionary *gShadowKeyEquivDB = nil;
   NS_OBJC_END_TRY_ABORT_BLOCK;
 }
 
+- (BOOL)nsMenuX_NSMenu_performKeyEquivalent:(NSEvent *)theEvent
+{
+  // On OS X 10.4.X (Tiger), Objective-C exceptions can occur during calls to
+  // [NSMenu performKeyEquivalent:] (from [GeckoNSMenu performKeyEquivalent:]
+  // or otherwise) that shouldn't be fatal (see bmo bug 461381).  So on Tiger
+  // we hook this system call to eat (and log) all Objective-C exceptions that
+  // occur during its execution.  Since we don't call XPCOM code from here,
+  // this will never cause XPCOM objects to be left on the stack without
+  // cleanup.
+  NS_OBJC_BEGIN_TRY_LOGONLY_BLOCK_RETURN;
+  return [self nsMenuX_NSMenu_performKeyEquivalent:theEvent];
+  NS_OBJC_END_TRY_LOGONLY_BLOCK_RETURN(NO);
+}
+
 @end
 
 // This class is needed to keep track of when the OS is (re)indexing all of

xpcom/base/nsObjCExceptions.h

@@ -240,4 +240,10 @@ NS_OBJC_TRY(_e, )
                                           nsObjCExceptionLog(_exn);             \
                                         }
 
+#define NS_OBJC_BEGIN_TRY_LOGONLY_BLOCK_RETURN    @try {
+#define NS_OBJC_END_TRY_LOGONLY_BLOCK_RETURN(_rv) } @catch(NSException *_exn) { \
+                                                    nsObjCExceptionLog(_exn);   \
+                                                  }                             \
+                                                  return _rv;
+
 #endif // nsObjCExceptions_h_