weex_core/Source/include/wtf/MetaAllocatorHandle.h

/*
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 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
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 *     notice, this list of conditions and the following disclaimer. 
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 *     notice, this list of conditions and the following disclaimer in the
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 *     its contributors may be used to endorse or promote products derived
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#ifndef WTF_MetaAllocatorHandle_h
#define WTF_MetaAllocatorHandle_h

#include <wtf/Assertions.h>
#include <wtf/RedBlackTree.h>
#include <wtf/ThreadSafeRefCounted.h>
#include <wtf/RefPtr.h>

namespace WTF {

class MetaAllocator;
class PrintStream;

class MetaAllocatorHandle : public ThreadSafeRefCounted<MetaAllocatorHandle>, public RedBlackTree<MetaAllocatorHandle, void*>::Node {
private:
    MetaAllocatorHandle(MetaAllocator*, void* start, size_t sizeInBytes, void* ownerUID);
    
public:
    WTF_EXPORT_PRIVATE ~MetaAllocatorHandle();
    
    void* start() const
    {
        return m_start;
    }
    
    void* end() const
    {
        return reinterpret_cast<void*>(endAsInteger());
    }
    
    uintptr_t startAsInteger() const
    {
        return reinterpret_cast<uintptr_t>(m_start);
    }
    
    uintptr_t endAsInteger() const
    {
        return startAsInteger() + m_sizeInBytes;
    }
        
    size_t sizeInBytes() const
    {
        return m_sizeInBytes;
    }
    
    bool containsIntegerAddress(uintptr_t address) const
    {
        return address - startAsInteger() < sizeInBytes();
    }
    
    bool contains(void* address) const
    {
        return containsIntegerAddress(reinterpret_cast<uintptr_t>(address));
    }
        
    WTF_EXPORT_PRIVATE void shrink(size_t newSizeInBytes);
    
    bool isManaged()
    {
        return !!m_allocator;
    }
        
    MetaAllocator* allocator()
    {
        ASSERT(m_allocator);
        return m_allocator;
    }

    void* ownerUID()
    {
        return m_ownerUID;
    }

    void* key()
    {
        return m_start;
    }

    WTF_EXPORT_PRIVATE void dump(PrintStream& out) const;
    
private:
    friend class MetaAllocator;
    
    MetaAllocator* m_allocator;
    void* m_start;
    size_t m_sizeInBytes;
    void* m_ownerUID;
};

}

#endif