1 files changed, 142 insertions, 0 deletions
diff --git a/Source/WebCore/dom/NoEventDispatchAssertion.h b/Source/WebCore/dom/NoEventDispatchAssertion.h
new file mode 100644
index 000000000..16038611b
--- /dev/null
+++ b/Source/WebCore/dom/NoEventDispatchAssertion.h
@@ -0,0 +1,142 @@
+/*
+ * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
+ *           (C) 1999 Antti Koivisto (koivisto@kde.org)
+ *           (C) 2001 Dirk Mueller (mueller@kde.org)
+ * Copyright (C) 2004-2016 Apple Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#pragma once
+
+#include "ContainerNode.h"
+#include <wtf/MainThread.h>
+
+namespace WebCore {
+
+class NoEventDispatchAssertion {
+public:
+    NoEventDispatchAssertion()
+    {
+#if !ASSERT_DISABLED
+        if (!isMainThread())
+            return;
+        ++s_count;
+#endif
+    }
+
+    NoEventDispatchAssertion(const NoEventDispatchAssertion&)
+        : NoEventDispatchAssertion()
+    {
+    }
+
+    ~NoEventDispatchAssertion()
+    {
+#if !ASSERT_DISABLED
+        if (!isMainThread())
+            return;
+        ASSERT(s_count);
+        s_count--;
+#endif
+    }
+
+    static bool isEventAllowedInMainThread()
+    {
+#if ASSERT_DISABLED
+        return true;
+#else
+        return !isMainThread() || !s_count;
+#endif
+    }
+
+    static bool isEventDispatchAllowedInSubtree(Node& node)
+    {
+        return isEventAllowedInMainThread() || EventAllowedScope::isAllowedNode(node);
+    }
+
+#if !ASSERT_DISABLED
+    class EventAllowedScope {
+    public:
+        explicit EventAllowedScope(ContainerNode& userAgentContentRoot)
+            : m_eventAllowedTreeRoot(userAgentContentRoot)
+            , m_previousScope(s_currentScope)
+        {
+            s_currentScope = this;
+        }
+
+        ~EventAllowedScope()
+        {
+            s_currentScope = m_previousScope;
+        }
+
+        static bool isAllowedNode(Node& node)
+        {
+            return s_currentScope && s_currentScope->isAllowedNodeInternal(node);
+        }
+
+    private:
+        bool isAllowedNodeInternal(Node& node)
+        {
+            return m_eventAllowedTreeRoot->contains(&node) || (m_previousScope && m_previousScope->isAllowedNodeInternal(node));
+        }
+
+        Ref<ContainerNode> m_eventAllowedTreeRoot;
+
+        EventAllowedScope* m_previousScope;
+        static EventAllowedScope* s_currentScope;
+    };
+#else
+    class EventAllowedScope {
+    public:
+        explicit EventAllowedScope(ContainerNode&) { }
+        static bool isAllowedNode(Node&) { return true; }
+    };
+#endif
+
+#if !ASSERT_DISABLED
+    class DisableAssertionsInScope {
+    public:
+        DisableAssertionsInScope()
+        {
+            if (!isMainThread())
+                return;
+            s_existingCount = s_count;
+            s_count = 0;
+        }
+
+        ~DisableAssertionsInScope()
+        {
+            s_count = s_existingCount;
+            s_existingCount = 0;
+        }
+    private:
+        WEBCORE_EXPORT static unsigned s_existingCount;
+    };
+#else
+    class DisableAssertionsInScope {
+    public:
+        DisableAssertionsInScope() { }
+    };
+#endif
+
+#if !ASSERT_DISABLED
+private:
+    WEBCORE_EXPORT static unsigned s_count;
+#endif
+};
+
+} // namespace WebCore