1 files changed, 85 insertions, 0 deletions
diff --git a/Source/WebCore/platform/GenericTaskQueue.cpp b/Source/WebCore/platform/GenericTaskQueue.cpp
new file mode 100644
index 000000000..1aa7e1b87
--- /dev/null
+++ b/Source/WebCore/platform/GenericTaskQueue.cpp
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2016 Apple Inc. All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "GenericTaskQueue.h"
+
+#include <wtf/MainThread.h>
+#include <wtf/NeverDestroyed.h>
+
+namespace WebCore {
+
+TaskDispatcher<Timer>::TaskDispatcher()
+    : m_weakPtrFactory(this)
+{
+}
+
+void TaskDispatcher<Timer>::postTask(Function<void()>&& function)
+{
+    m_pendingTasks.append(WTFMove(function));
+    pendingDispatchers().append(m_weakPtrFactory.createWeakPtr());
+    if (!sharedTimer().isActive())
+        sharedTimer().startOneShot(0);
+}
+
+Timer& TaskDispatcher<Timer>::sharedTimer()
+{
+    ASSERT(isMainThread());
+    static NeverDestroyed<Timer> timer(TaskDispatcher<Timer>::sharedTimerFired);
+    return timer.get();
+}
+
+void TaskDispatcher<Timer>::sharedTimerFired()
+{
+    ASSERT(!sharedTimer().isActive());
+    ASSERT(!pendingDispatchers().isEmpty());
+
+    // Copy the pending events first because we don't want to process synchronously the new events
+    // queued by the JS events handlers that are executed in the loop below.
+    Deque<WeakPtr<TaskDispatcher<Timer>>> queuedDispatchers = WTFMove(pendingDispatchers());
+    while (!queuedDispatchers.isEmpty()) {
+        WeakPtr<TaskDispatcher<Timer>> dispatcher = queuedDispatchers.takeFirst();
+        if (!dispatcher)
+            continue;
+        dispatcher->dispatchOneTask();
+    }
+}
+
+Deque<WeakPtr<TaskDispatcher<Timer>>>& TaskDispatcher<Timer>::pendingDispatchers()
+{
+    ASSERT(isMainThread());
+    static NeverDestroyed<Deque<WeakPtr<TaskDispatcher<Timer>>>> dispatchers;
+    return dispatchers.get();
+}
+
+void TaskDispatcher<Timer>::dispatchOneTask()
+{
+    ASSERT(!m_pendingTasks.isEmpty());
+    auto task = m_pendingTasks.takeFirst();
+    task();
+}
+
+}
+