godot/thirdparty/thekla_atlas/nvcore/Ptr.h
Hein-Pieter van Braam bf05309af7 Import thekla_atlas
As requested by reduz, an import of thekla_atlas into thirdparty/
2017-12-08 15:47:15 +01:00

323 lines
7.7 KiB
C++

// This code is in the public domain -- Ignacio Castaño <castano@gmail.com>
#ifndef NV_CORE_PTR_H
#define NV_CORE_PTR_H
#include "nvcore.h"
#include "Debug.h"
#include "RefCounted.h"
namespace nv
{
class WeakProxy;
/** Simple auto pointer template class.
*
* This is very similar to the standard auto_ptr class, but with some
* additional limitations to make its use less error prone:
* - Copy constructor and assignment operator are disabled.
* - reset method is removed.
*
* The semantics of the standard auto_ptr are not clear and change depending
* on the std implementation. For a discussion of the problems of auto_ptr read:
* http://www.awprofessional.com/content/images/020163371X/autoptrupdate\auto_ptr_update.html
*/
template <class T>
class AutoPtr
{
NV_FORBID_COPY(AutoPtr);
NV_FORBID_HEAPALLOC();
public:
/// Ctor.
AutoPtr(T * p = NULL) : m_ptr(p) { }
template <class Q>
AutoPtr(Q * p) : m_ptr(static_cast<T *>(p)) { }
/// Dtor. Deletes owned pointer.
~AutoPtr() {
delete m_ptr;
m_ptr = NULL;
}
/// Delete owned pointer and assign new one.
void operator=( T * p ) {
if (p != m_ptr)
{
delete m_ptr;
m_ptr = p;
}
}
template <class Q>
void operator=( Q * p ) {
if (p != m_ptr)
{
delete m_ptr;
m_ptr = static_cast<T *>(p);
}
}
/// Member access.
T * operator -> () const {
nvDebugCheck(m_ptr != NULL);
return m_ptr;
}
/// Get reference.
T & operator*() const {
nvDebugCheck(m_ptr != NULL);
return *m_ptr;
}
/// Get pointer.
T * ptr() const { return m_ptr; }
/// Relinquish ownership of the underlying pointer and returns that pointer.
T * release() {
T * tmp = m_ptr;
m_ptr = NULL;
return tmp;
}
/// Const pointer equal comparation.
friend bool operator == (const AutoPtr<T> & ap, const T * const p) {
return (ap.ptr() == p);
}
/// Const pointer nequal comparation.
friend bool operator != (const AutoPtr<T> & ap, const T * const p) {
return (ap.ptr() != p);
}
/// Const pointer equal comparation.
friend bool operator == (const T * const p, const AutoPtr<T> & ap) {
return (ap.ptr() == p);
}
/// Const pointer nequal comparation.
friend bool operator != (const T * const p, const AutoPtr<T> & ap) {
return (ap.ptr() != p);
}
private:
T * m_ptr;
};
/// Smart pointer template class.
template <class BaseClass>
class SmartPtr {
public:
// BaseClass must implement addRef() and release().
typedef SmartPtr<BaseClass> ThisType;
/// Default ctor.
SmartPtr() : m_ptr(NULL)
{
}
/// Other type assignment.
template <class OtherBase>
SmartPtr( const SmartPtr<OtherBase> & tc )
{
m_ptr = static_cast<BaseClass *>( tc.ptr() );
if (m_ptr) {
m_ptr->addRef();
}
}
/// Copy ctor.
SmartPtr( const ThisType & bc )
{
m_ptr = bc.ptr();
if (m_ptr) {
m_ptr->addRef();
}
}
/// Copy cast ctor. SmartPtr(NULL) is valid.
explicit SmartPtr( BaseClass * bc )
{
m_ptr = bc;
if (m_ptr) {
m_ptr->addRef();
}
}
/// Dtor.
~SmartPtr()
{
set(NULL);
}
/// -> operator.
BaseClass * operator -> () const
{
nvCheck( m_ptr != NULL );
return m_ptr;
}
/// * operator.
BaseClass & operator*() const
{
nvCheck( m_ptr != NULL );
return *m_ptr;
}
/// Get pointer.
BaseClass * ptr() const
{
return m_ptr;
}
/// Other type assignment.
template <class OtherBase>
void operator = ( const SmartPtr<OtherBase> & tc )
{
set( static_cast<BaseClass *>(tc.ptr()) );
}
/// This type assignment.
void operator = ( const ThisType & bc )
{
set( bc.ptr() );
}
/// Pointer assignment.
void operator = ( BaseClass * bc )
{
set( bc );
}
/// Other type equal comparation.
template <class OtherBase>
bool operator == ( const SmartPtr<OtherBase> & other ) const
{
return m_ptr == other.ptr();
}
/// This type equal comparation.
bool operator == ( const ThisType & bc ) const
{
return m_ptr == bc.ptr();
}
/// Const pointer equal comparation.
bool operator == ( const BaseClass * const bc ) const
{
return m_ptr == bc;
}
/// Other type not equal comparation.
template <class OtherBase>
bool operator != ( const SmartPtr<OtherBase> & other ) const
{
return m_ptr != other.ptr();
}
/// Other type not equal comparation.
bool operator != ( const ThisType & bc ) const
{
return m_ptr != bc.ptr();
}
/// Const pointer not equal comparation.
bool operator != (const BaseClass * const bc) const
{
return m_ptr != bc;
}
/// This type lower than comparation.
bool operator < (const ThisType & p) const
{
return m_ptr < p.ptr();
}
bool isValid() const {
return isValidPtr(m_ptr);
}
private:
// Set this pointer.
void set( BaseClass * p )
{
if (p) p->addRef();
if (m_ptr) m_ptr->release();
m_ptr = p;
}
private:
BaseClass * m_ptr;
};
/// Smart pointer template class.
template <class T>
class WeakPtr {
public:
WeakPtr() {}
WeakPtr(T * p) { operator=(p); }
WeakPtr(const SmartPtr<T> & p) { operator=(p.ptr()); }
// Default constructor and assignment from weak_ptr<T> are OK.
void operator=(T * p)
{
if (p) {
m_proxy = p->getWeakProxy();
nvDebugCheck(m_proxy != NULL);
nvDebugCheck(m_proxy->ptr() == p);
}
else {
m_proxy = NULL;
}
}
void operator=(const SmartPtr<T> & ptr) { operator=(ptr.ptr()); }
bool operator==(const SmartPtr<T> & p) const { return ptr() == p.ptr(); }
bool operator!=(const SmartPtr<T> & p) const { return ptr() != p.ptr(); }
bool operator==(const WeakPtr<T> & p) const { return ptr() == p.ptr(); }
bool operator!=(const WeakPtr<T> & p) const { return ptr() != p.ptr(); }
bool operator==(T * p) const { return ptr() == p; }
bool operator!=(T * p) const { return ptr() != p; }
T * operator->() const
{
T * p = ptr();
nvDebugCheck(p != NULL);
return p;
}
T * ptr() const
{
if (m_proxy != NULL) {
return static_cast<T *>(m_proxy->ptr());
}
return NULL;
}
private:
mutable SmartPtr<WeakProxy> m_proxy;
};
} // nv namespace
#endif // NV_CORE_PTR_H