public/web/WebScopedUserGesture.h

/*
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#ifndef WebScopedUserGesture_h
#define WebScopedUserGesture_h

#include "../platform/WebPrivateOwnPtr.h"

namespace blink {

class UserGestureIndicator;
class WebUserGestureToken;

// An instance of this class, while kept alive, will indicate that we are in
// the context of a known user gesture. To use, create one, perform whatever
// actions were done under color of a known user gesture, and then delete it.
// Usually this will be done on the stack.
//
// SECURITY WARNING: Do not create several instances of this class for the same
// user gesture. Doing so might enable malicious code to work around certain
// restrictions such as opening multiple windows.
// Instead, obtain the current WebUserGestureToken from the
// WebUserGestureIndicator, and use this token to create a
// WebScopedUserGesture. If the token was alrady consumed, the new
// WebScopedUserGesture will not indicate that we are in the context of a user
// gesture.
class WebScopedUserGesture {
public:
    explicit WebScopedUserGesture(const WebUserGestureToken& token) { initializeWithToken(token); }
    WebScopedUserGesture() { initialize(); }
    ~WebScopedUserGesture() { reset(); }

private:
    BLINK_EXPORT void initialize();
    BLINK_EXPORT void initializeWithToken(const WebUserGestureToken&);
    BLINK_EXPORT void reset();

    WebPrivateOwnPtr<UserGestureIndicator> m_indicator;
};

} // namespace blink

#endif // WebScopedUserGesture_h