public/platform/WebWaitableEvent.h

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#ifndef WebWaitableEvent_h
#define WebWaitableEvent_h

#include "WebCommon.h"

namespace blink {

// Provides a thread synchronization that can be used to allow one thread to
// wait until another thread to finish some work.
class WebWaitableEvent {
public:
    // If ResetPolicy::Manual is specified on creation, to set the event state
    // to non-signaled, a consumer must call reset().  Otherwise, the system
    // automatically resets the event state to non-signaled after a single
    // waiting thread has been released.
    enum class ResetPolicy { Auto, Manual };

    // Specify the initial state on creation.
    enum class InitialState { NonSignaled, Signaled };

    virtual ~WebWaitableEvent() {}

    // Puts the event in the un-signaled state.
    virtual void reset() {}

    // Waits indefinitely for the event to be signaled.
    virtual void wait() {}

    // Puts the event in the signaled state. Causing any thread blocked on Wait
    // to be woken up. The event state is reset to non-signaled after
    // a waiting thread has been released.
    virtual void signal() {}
};

} // namespace blink

#endif // WebWaitableEvent_h