WebScopedMicrotaskSuppression.h   [plain text]

/*
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 *
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#ifndef WebScopedMicrotaskSuppression_h
#define WebScopedMicrotaskSuppression_h

#include "platform/WebPrivateOwnPtr.h"

namespace WebKit {

// This class wraps V8RecursionScope::BypassMicrotaskCheckpoint. Please
// see V8RecursionScope.h for full usage. Short story: Embedder calls into
// script contexts which also host page script must do one of two things:
//
//   1. If the call may cause any page/author script to run, it must be
//      captured for pre/post work (e.g. inspector instrumentation/microtask
//      delivery) and thus be invoked through WebFrame (e.g. executeScript*,
//      callFunction*).
//   2. If the call will not cause any page/author script to run, the call
//      should be made directly via the v8 context, but the callsite must be
//      accompanied by a stack allocated WebScopedMicrotaskSuppression, e.g.:
//
//        ...
//        {
//            WebKit::WebScopedMicrotaskSuppression suppression;
//            func->Call(global, argv, args);
//        }
//        ...
//
class WebScopedMicrotaskSuppression {
public:
    WebScopedMicrotaskSuppression() { initialize(); }
    ~WebScopedMicrotaskSuppression() { reset(); }

private:
    WEBKIT_EXPORT void initialize();
    WEBKIT_EXPORT void reset();

#ifndef NDEBUG
    class Impl;
    WebPrivateOwnPtr<Impl> m_impl;
#endif
};

} // WebKit

#endif