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#ifndef CPPDB_REF_PTR_H
#define CPPDB_REF_PTR_H
#include <cppdb/errors.h>
#include <cppdb/atomic_counter.h>
namespace cppdb {
template<typename T>
class ref_ptr {
public:
ref_ptr(T *v=0) : p(0)
{
reset(v);
}
~ref_ptr()
{
reset();
}
ref_ptr(ref_ptr const &other) : p(0)
{
reset(other.p);
}
ref_ptr const &operator=(ref_ptr const &other)
{
reset(other.p);
return *this;
}
T *get() const
{
return p;
}
operator bool() const
{
return p!=0;
}
T *operator->() const
{
if(!p)
throw cppdb_error("Attempt to access an empty object");
return p;
}
T &operator*() const
{
if(!p)
throw cppdb_error("Attempt to access an empty object");
return *p;
}
void reset(T *v=0)
{
if(v==p)
return;
if(p) {
if(p->del_ref() == 0) {
T::dispose(p);
}
p=0;
}
if(v) {
v->add_ref();
}
p=v;
}
private:
T *p;
};
class ref_counted {
public:
ref_counted() : count_(0)
{
}
virtual ~ref_counted()
{
}
long add_ref()
{
return ++count_;
}
long use_count() const
{
long val = count_;
return val;
}
long del_ref()
{
return --count_;
}
static void dispose(ref_counted *p)
{
delete p;
}
private:
atomic_counter count_;
};
} // cppdb
#endif
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