RefCountedObject.h

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 *  Copyright 2018 Rice University                                           *
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 *  Licensed under the Apache License, Version 2.0 (the "License");          *
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#ifndef REF_COUNTED_OBJECT_H
#define REF_COUNTED_OBJECT_H

#include <cstddef>
#include <iostream>
#include <vector>
#include <algorithm>
#include <iterator>
#include <cstring>

namespace pdb {

// When an Object is stored in an allocator, we have to have a bit of meta-data
// associated with it.  It is the job of the RefCountedObject class to manage
// this meta-data, along with the Object.  Specifically, we need:
//
// (1) A count of the number of Handles that are currently pointing to the Object.
//     When this count goes down to zero, then the object is unreachable and can
//     be freed.
//
class Object;
class PDBTemplateBase;

template <class ObjType>
class RefCountedObject {

public:
    // set the number of references to this object to a specific value
    void setRefCount(unsigned toMe);

    // increment the reference count for the object by one
    void incRefCount();

    // return the ref count
    unsigned getRefCount();

    // decrement the ref count for the object by one.  If the value of the
    // reference count goes down to zero, the object is deleted using the
    // PDBTemplateBased object
    void decRefCount(PDBTemplateBase& typeInfo);

    // get a pointer to the object itself
    ObjType* getObject() const;

private:
    // so that no one can create one
    RefCountedObject() {}
};
}

#include "RefCountedObject.cc"

#endif