atomic.h

/* Atomic operations */
/* SPDX-FileCopyrightText: Copyright © 2023 Wim Taymans */
/* SPDX-License-Identifier: MIT */
 
#ifndef SPA_ATOMIC_H
#define SPA_ATOMIC_H
 
#ifdef __cplusplus
extern "C" {
#endif


#define SPA_ATOMIC_CAS(v,ov,nv)                                         \
({                                                                      \
        __typeof__(v) __ov = (ov);                                      \
        __atomic_compare_exchange_n(&(v), &__ov, (nv),                  \
                        0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST);         \
})


#define SPA_ATOMIC_DEC(s)               __atomic_sub_fetch(&(s), 1, __ATOMIC_SEQ_CST)

#define SPA_ATOMIC_INC(s)               __atomic_add_fetch(&(s), 1, __ATOMIC_SEQ_CST)

#define SPA_ATOMIC_LOAD(s)              __atomic_load_n(&(s), __ATOMIC_SEQ_CST)

#define SPA_LOAD_ONCE(s)                __atomic_load_n(&(s), __ATOMIC_RELAXED)

#define SPA_STORE_ONCE(s,v)             __atomic_store_n(&(s), (v), __ATOMIC_RELAXED)

#define SPA_ATOMIC_STORE(s,v)           __atomic_store_n(&(s), (v), __ATOMIC_SEQ_CST)
#define SPA_ATOMIC_XCHG(s,v)            __atomic_exchange_n(&(s), (v), __ATOMIC_SEQ_CST)

#define SPA_SEQ_WRITE(s)                SPA_ATOMIC_INC(s)
#define SPA_SEQ_WRITE_SUCCESS(s1,s2)    ((s1) + 1 == (s2) && ((s2) & 1) == 0)

#define SPA_SEQ_READ(s)                 SPA_ATOMIC_LOAD(s)
#define SPA_SEQ_READ_SUCCESS(s1,s2)     ((s1) == (s2) && ((s2) & 1) == 0)

 
#ifdef __cplusplus
} /* extern "C" */
#endif
 
#endif /* SPA_ATOMIC_H */