webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 98 insertions, 0 deletions

diff --git a/Source/WebCore/dom/Microtasks.cpp b/Source/WebCore/dom/Microtasks.cpp
new file mode 100644
index 000000000..e5a2c951e
--- /dev/null
+++ b/Source/WebCore/dom/Microtasks.cpp
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+/*
+ * Copyright (C) 2014 Yoav Weiss (yoav@yoav.ws)
+ * Copyright (C) 2015 Akamai Technologies 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.
+ *
+ */
+
+#include "config.h"
+#include "Microtasks.h"
+
+#include <wtf/MainThread.h>
+#include <wtf/SetForScope.h>
+
+namespace WebCore {
+
+void Microtask::removeSelfFromQueue(MicrotaskQueue& queue)
+{
+    queue.remove(*this);
+}
+
+MicrotaskQueue::MicrotaskQueue()
+    : m_timer(*this, &MicrotaskQueue::timerFired)
+{
+}
+
+MicrotaskQueue::~MicrotaskQueue()
+{
+}
+
+MicrotaskQueue& MicrotaskQueue::mainThreadQueue()
+{
+    ASSERT(isMainThread());
+    static NeverDestroyed<MicrotaskQueue> queue;
+    return queue;
+}
+
+void MicrotaskQueue::append(std::unique_ptr<Microtask>&& task)
+{
+    m_microtaskQueue.append(WTFMove(task));
+
+    m_timer.startOneShot(0);
+}
+
+void MicrotaskQueue::remove(const Microtask& task)
+{
+    for (size_t i = 0; i < m_microtaskQueue.size(); ++i) {
+        if (m_microtaskQueue[i].get() == &task) {
+            m_microtaskQueue.remove(i);
+            return;
+        }
+    }
+}
+
+void MicrotaskQueue::timerFired()
+{
+    performMicrotaskCheckpoint();
+}
+
+void MicrotaskQueue::performMicrotaskCheckpoint()
+{
+    if (m_performingMicrotaskCheckpoint)
+        return;
+
+    SetForScope<bool> change(m_performingMicrotaskCheckpoint, true);
+
+    Vector<std::unique_ptr<Microtask>> toKeep;
+    while (!m_microtaskQueue.isEmpty()) {
+        Vector<std::unique_ptr<Microtask>> queue = WTFMove(m_microtaskQueue);
+        for (auto& task : queue) {
+            auto result = task->run();
+            switch (result) {
+            case Microtask::Result::Done:
+                break;
+            case Microtask::Result::KeepInQueue:
+                toKeep.append(WTFMove(task));
+                break;
+            }
+        }
+    }
+
+    m_microtaskQueue = WTFMove(toKeep);
+}
+
+} // namespace WebCore