#ifndef ATOMIC_H
#define ATOMIC_H

#include "irq.h"

/*
 * Atomic operations (implemented by locking out IRQ)
 */

#define atomic_cmpxchg(__p,__o,__n)		  \
    ({						  \
	volatile __typeof__(__p) *___p = &(__p);  \
    irqmask_t __irq = disable_irqs();		  \
    bool __ok = *___p == (__o);			  \
    if (__ok)					  \
	*___p = (__n);				  \
    restore_irqs(__irq);			  \
    __ok;					  \
    })

#define atomic_xchg_op(__p,__var,__op)			\
    ({							\
	volatile __typeof__(__p) *___p = &(__p);	\
	irqmask_t __irq = disable_irqs();		\
	__typeof__(*___p) __var = *___p;		\
	*___p = (__op);					\
	restore_irqs(__irq);				\
	__var;						\
    })

#define atomic_xchg(__p,__a)		atomic_xchg_op(__p,__v,__v)
#define atomic_xchg_add(__p,__a)	atomic_xchg_op(__p,__v,__v + (__a))
#define atomic_xchg_and(__p,__a)	atomic_xchg_op(__p,__v,__v & (__a))
#define atomic_xchg_or(__p,__a)		atomic_xchg_op(__p,__v,__v | (__a))
#define atomic_xchg_xor(__p,__a)	atomic_xchg_op(__p,__v,__v ^ (__a))

#endif /* ATOMIC_H */