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#if !defined(__OBJECT_H)
#define __OBJECT_H
#include <atomic>
#include "constructor_stats.h"
/// Reference counted object base class
class Object {
public:
/// Default constructor
Object() { print_default_created(this); }
/// Copy constructor
Object(const Object &) : m_refCount(0) { print_copy_created(this); }
/// Return the current reference count
int getRefCount() const { return m_refCount; };
/// Increase the object's reference count by one
void incRef() const { ++m_refCount; }
/** \brief Decrease the reference count of
* the object and possibly deallocate it.
*
* The object will automatically be deallocated once
* the reference count reaches zero.
*/
void decRef(bool dealloc = true) const {
--m_refCount;
if (m_refCount == 0 && dealloc)
delete this;
else if (m_refCount < 0)
throw std::runtime_error("Internal error: reference count < 0!");
}
virtual std::string toString() const = 0;
protected:
/** \brief Virtual protected deconstructor.
* (Will only be called by \ref ref)
*/
virtual ~Object() { print_destroyed(this); }
private:
mutable std::atomic<int> m_refCount { 0 };
};
// Tag class used to track constructions of ref objects. When we track constructors, below, we
// track and print out the actual class (e.g. ref<MyObject>), and *also* add a fake tracker for
// ref_tag. This lets us check that the total number of ref<Anything> constructors/destructors is
// correct without having to check each individual ref<Whatever> type individually.
class ref_tag {};
/**
* \brief Reference counting helper
*
* The \a ref refeference template is a simple wrapper to store a
* pointer to an object. It takes care of increasing and decreasing
* the reference count of the object. When the last reference goes
* out of scope, the associated object will be deallocated.
*
* \ingroup libcore
*/
template <typename T> class ref {
public:
/// Create a nullptr reference
ref() : m_ptr(nullptr) { print_default_created(this); track_default_created((ref_tag*) this); }
/// Construct a reference from a pointer
ref(T *ptr) : m_ptr(ptr) {
if (m_ptr) ((Object *) m_ptr)->incRef();
print_created(this, "from pointer", m_ptr); track_created((ref_tag*) this, "from pointer");
}
/// Copy constructor
ref(const ref &r) : m_ptr(r.m_ptr) {
if (m_ptr)
((Object *) m_ptr)->incRef();
print_copy_created(this, "with pointer", m_ptr); track_copy_created((ref_tag*) this);
}
/// Move constructor
ref(ref &&r) : m_ptr(r.m_ptr) {
r.m_ptr = nullptr;
print_move_created(this, "with pointer", m_ptr); track_move_created((ref_tag*) this);
}
/// Destroy this reference
~ref() {
if (m_ptr)
((Object *) m_ptr)->decRef();
print_destroyed(this); track_destroyed((ref_tag*) this);
}
/// Move another reference into the current one
ref& operator=(ref&& r) {
print_move_assigned(this, "pointer", r.m_ptr); track_move_assigned((ref_tag*) this);
if (*this == r)
return *this;
if (m_ptr)
((Object *) m_ptr)->decRef();
m_ptr = r.m_ptr;
r.m_ptr = nullptr;
return *this;
}
/// Overwrite this reference with another reference
ref& operator=(const ref& r) {
print_copy_assigned(this, "pointer", r.m_ptr); track_copy_assigned((ref_tag*) this);
if (m_ptr == r.m_ptr)
return *this;
if (m_ptr)
((Object *) m_ptr)->decRef();
m_ptr = r.m_ptr;
if (m_ptr)
((Object *) m_ptr)->incRef();
return *this;
}
/// Overwrite this reference with a pointer to another object
ref& operator=(T *ptr) {
print_values(this, "assigned pointer"); track_values((ref_tag*) this, "assigned pointer");
if (m_ptr == ptr)
return *this;
if (m_ptr)
((Object *) m_ptr)->decRef();
m_ptr = ptr;
if (m_ptr)
((Object *) m_ptr)->incRef();
return *this;
}
/// Compare this reference with another reference
bool operator==(const ref &r) const { return m_ptr == r.m_ptr; }
/// Compare this reference with another reference
bool operator!=(const ref &r) const { return m_ptr != r.m_ptr; }
/// Compare this reference with a pointer
bool operator==(const T* ptr) const { return m_ptr == ptr; }
/// Compare this reference with a pointer
bool operator!=(const T* ptr) const { return m_ptr != ptr; }
/// Access the object referenced by this reference
T* operator->() { return m_ptr; }
/// Access the object referenced by this reference
const T* operator->() const { return m_ptr; }
/// Return a C++ reference to the referenced object
T& operator*() { return *m_ptr; }
/// Return a const C++ reference to the referenced object
const T& operator*() const { return *m_ptr; }
/// Return a pointer to the referenced object
operator T* () { return m_ptr; }
/// Return a const pointer to the referenced object
T* get_ptr() { return m_ptr; }
/// Return a pointer to the referenced object
const T* get_ptr() const { return m_ptr; }
private:
T *m_ptr;
};
#endif /* __OBJECT_H */
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