perThreadRef.h

/* Copyright (c) 2008-2013, Stefan Eilemann <eile@equalizergraphics.com>
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License version 2.1 as published
 * by the Free Software Foundation.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef LUNCHBOX_PERTHREADREF_H
#define LUNCHBOX_PERTHREADREF_H

#include <lunchbox/tls.h> // member

namespace lunchbox
{
template <typename T>
class PerThreadRef : public boost::noncopyable
{
public:
    PerThreadRef();
    ~PerThreadRef();

    PerThreadRef<T>& operator=(RefPtr<T> data);

    PerThreadRef<T>& operator=(const PerThreadRef<T>& rhs);

    RefPtr<const T> get() const;
    RefPtr<T> get();

    T* getPointer();

    T* operator->();

    const T* operator->() const;

    bool operator==(const PerThreadRef& rhs) const
    {
        return (get() == rhs.get());
    }

    bool operator==(const RefPtr<T>& rhs) const { return (get() == rhs); }
    bool operator!=(const RefPtr<T>& rhs) const { return (get() != rhs); }
    bool operator!() const;

    bool isValid() const;

private:
    TLS tls_;
};

template <typename T>
PerThreadRef<T>::PerThreadRef()
    : tls_(0)
{
}

template <typename T>
PerThreadRef<T>::~PerThreadRef()
{
    RefPtr<T> object = get();
    object.unref();
}

template <typename T>
PerThreadRef<T>& PerThreadRef<T>::operator=(RefPtr<T> data)
{
    data.ref(); // ref new

    RefPtr<T> object = get();
    tls_.set(static_cast<const void*>(data.get()));

    object.unref(); // unref old
    return *this;
}

template <typename T>
PerThreadRef<T>& PerThreadRef<T>::operator=(const PerThreadRef<T>& rhs)
{
    RefPtr<T> newObject = rhs.get();
    newObject.ref(); // ref new

    RefPtr<T> object = get();
    tls_.set(rhs.tls_.get());

    object.unref(); // unref old
    return *this;
}

template <typename T>
RefPtr<const T> PerThreadRef<T>::get() const
{
    return static_cast<const T*>(tls_.get());
}

template <typename T>
RefPtr<T> PerThreadRef<T>::get()
{
    return static_cast<T*>(tls_.get());
}

template <typename T>
T* PerThreadRef<T>::getPointer()
{
    return static_cast<T*>(tls_.get());
}

template <typename T>
T* PerThreadRef<T>::operator->()
{
    LBASSERT(tls_.get());
    return static_cast<T*>(tls_.get());
}

template <typename T>
const T* PerThreadRef<T>::operator->() const
{
    LBASSERT(tls_.get());
    return static_cast<const T*>(tls_.get());
}

template <typename T>
bool PerThreadRef<T>::operator!() const
{
    return tls_.get() == 0;
}

template <typename T>
bool PerThreadRef<T>::isValid() const
{
    return tls_.get() != 0;
}
}
#endif // LUNCHBOX_PERTHREADREF_H