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/*
Copyright (C) 2010 Tim Mayberry
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef PBD_ATOMIC_COUNTER_H
#define PBD_ATOMIC_COUNTER_H
#include <glib.h>
namespace PBD {
class atomic_counter
{
/**
* Prevent copying and assignment
*/
atomic_counter (const atomic_counter&);
atomic_counter& operator= (const atomic_counter&);
public:
atomic_counter (gint value = 0)
:
m_value(value)
{ }
gint get() const
{
return g_atomic_int_get (&m_value);
}
void set (gint new_value)
{
g_atomic_int_set (&m_value, new_value);
}
void increment ()
{
g_atomic_int_inc (&m_value);
}
void operator++ ()
{
increment ();
}
bool decrement_and_test ()
{
return g_atomic_int_dec_and_test (&m_value);
}
bool operator-- ()
{
return decrement_and_test ();
}
bool compare_and_exchange (gint old_value, gint new_value)
{
return g_atomic_int_compare_and_exchange
(
&m_value,
old_value,
new_value
);
}
/**
* convenience method, \see compare_and_exchange
*/
bool cas (gint old_value, gint new_value)
{
return compare_and_exchange (old_value, new_value);
}
private:
// Has to be mutable when using the apple version of gcc.
mutable volatile gint m_value;
};
} // namespace PBD
#endif // PBD_ATOMIC_COUNTER_H
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