refcount.h

/* -*- mode: C; c-basic-offset: 4 -*- */
/* ex: set shiftwidth=4 tabstop=4 expandtab: */
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#ifndef AA_REFCOUNT_H
#define AA_REFCOUNT_H

/***********************************/
/* Synchronized Reference Counting */
/***********************************/

#ifndef __cplusplus

#if  ( (__STDC_VERSION__ >= 201112L) && ! defined(__STD_NO_ATOMICS__) ) || defined (_STDATOMIC_H)

/* C11 atomics version */
#define AA_ATOMIC _Atomic
#define aa_mem_ref_inc aa_mem_ref_inc_atomic
#define aa_mem_ref_dec aa_mem_ref_dec_atomic

AA_API unsigned
aa_mem_ref_inc_atomic( AA_ATOMIC unsigned *count );

AA_API unsigned
aa_mem_ref_dec_atomic( AA_ATOMIC unsigned *count );

#else

#warning "No C11 atomics.  Include stdatomic.h or refcounts will be slow."

/* Mutex fallback version */
#define AA_ATOMIC
#define aa_mem_ref_inc aa_mem_ref_inc_mutex
#define aa_mem_ref_dec aa_mem_ref_dec_mutex

#endif /* __STDC_VERSION__ >= 201112L */

#else

/* TODO: C++ Atomic refcounts */

#endif


AA_API unsigned
aa_mem_ref_inc_mutex( unsigned *count );

AA_API unsigned
aa_mem_ref_dec_mutex( unsigned *count );

#endif /* AA_REFCOUNT_H */