Source/core/platform/MemoryUsageSupport.h

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
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#ifndef MemoryUsageSupport_h
#define MemoryUsageSupport_h

#include "wtf/Forward.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/text/WTFString.h"

namespace WebCore {

class MemoryUsageSupport {
public:
    // Returns the current space allocated for the pagefile, in MB.
    // That is committed size for Windows and virtual memory size for POSIX.
    static int memoryUsageMB();

    // Same as above, but always returns actual value, without any
    // caches.
    static int actualMemoryUsageMB();

    // Returns private and shared usage, in bytes. Private bytes is the amount of
    // memory currently allocated to this process that cannot be shared. Returns
    // false on platform specific error conditions.
    static bool processMemorySizesInBytes(size_t* privateBytes, size_t* sharedBytes);

    // A callback for requestProcessMemorySizes
    class ProcessMemorySizesCallback {
    public:
        virtual ~ProcessMemorySizesCallback() { }
        virtual void dataReceived(size_t privateBytes, size_t sharedBytes) = 0;
    };

    // Requests private and shared usage, in bytes. Private bytes is the amount of
    // memory currently allocated to this process that cannot be shared.
    static void requestProcessMemorySizes(PassOwnPtr<ProcessMemorySizesCallback> requestCallback);
};

} // namespace WebCore

#endif // MemoryUsageSupport_h