webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 105 insertions, 0 deletions

diff --git a/Source/WebCore/platform/graphics/gstreamer/MainThreadNotifier.h b/Source/WebCore/platform/graphics/gstreamer/MainThreadNotifier.h
new file mode 100644
index 000000000..96b587ff9
--- /dev/null
+++ b/Source/WebCore/platform/graphics/gstreamer/MainThreadNotifier.h
@@ -0,0 +1,105 @@
+/*
+ *  Copyright (C) 2015 Igalia S.L
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser 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
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#pragma once
+
+#include <wtf/Atomics.h>
+#include <wtf/Lock.h>
+#include <wtf/MainThread.h>
+#include <wtf/RunLoop.h>
+#include <wtf/ThreadSafeRefCounted.h>
+
+namespace WebCore {
+
+template <typename T>
+class MainThreadNotifier final : public ThreadSafeRefCounted<MainThreadNotifier<T>> {
+public:
+    static Ref<MainThreadNotifier> create()
+    {
+        return adoptRef(*new MainThreadNotifier());
+    }
+
+    template<typename F>
+    void notify(T notificationType, const F& callbackFunctor)
+    {
+        ASSERT(m_isValid.load());
+        if (isMainThread()) {
+            removePendingNotification(notificationType);
+            callbackFunctor();
+            return;
+        }
+
+        if (!addPendingNotification(notificationType))
+            return;
+
+        RunLoop::main().dispatch([this, protectedThis = makeRef(*this), notificationType, callback = std::function<void()>(callbackFunctor)] {
+            if (!m_isValid.load())
+                return;
+            if (removePendingNotification(notificationType))
+                callback();
+        });
+    }
+
+    void cancelPendingNotifications(unsigned mask = 0)
+    {
+        ASSERT(m_isValid.load());
+        LockHolder locker(m_pendingNotificationsLock);
+        if (mask)
+            m_pendingNotifications &= ~mask;
+        else
+            m_pendingNotifications = 0;
+    }
+
+    void invalidate()
+    {
+        ASSERT(m_isValid.load());
+        m_isValid.store(false);
+    }
+
+private:
+    MainThreadNotifier()
+    {
+        m_isValid.store(true);
+    }
+
+    bool addPendingNotification(T notificationType)
+    {
+        LockHolder locker(m_pendingNotificationsLock);
+        if (notificationType & m_pendingNotifications)
+            return false;
+        m_pendingNotifications |= notificationType;
+        return true;
+    }
+
+    bool removePendingNotification(T notificationType)
+    {
+        LockHolder locker(m_pendingNotificationsLock);
+        if (notificationType & m_pendingNotifications) {
+            m_pendingNotifications &= ~notificationType;
+            return true;
+        }
+        return false;
+    }
+
+    Lock m_pendingNotificationsLock;
+    unsigned m_pendingNotifications { 0 };
+    Atomic<bool> m_isValid;
+};
+
+} // namespace WebCore
+