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#ifndef SCM_ATOMICS_INTERNAL_H
#define SCM_ATOMICS_INTERNAL_H
/* Copyright 2016,2018-2019
Free Software Foundation, Inc.
This file is part of Guile.
Guile is free software: you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Guile 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 Guile. If not, see
<https://www.gnu.org/licenses/>. */
#include "scm.h"
#ifdef HAVE_STDATOMIC_H
#include <stdatomic.h>
static inline uint32_t
scm_atomic_subtract_uint32 (uint32_t *loc, uint32_t arg)
{
atomic_uint_least32_t *a_loc = (atomic_uint_least32_t *) loc;
return atomic_fetch_sub (a_loc, arg);
}
static inline _Bool
scm_atomic_compare_and_swap_uint32 (uint32_t *loc, uint32_t *expected,
uint32_t desired)
{
atomic_uint_least32_t *a_loc = (atomic_uint_least32_t *) loc;
return atomic_compare_exchange_weak (a_loc, expected, desired);
}
static inline void
scm_atomic_set_pointer (void **loc, void *val)
{
atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
atomic_store (a_loc, (uintptr_t) val);
}
static inline void *
scm_atomic_ref_pointer (void **loc)
{
atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
return (void *) atomic_load (a_loc);
}
static inline void
scm_atomic_set_scm (SCM *loc, SCM val)
{
atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
atomic_store (a_loc, SCM_UNPACK (val));
}
static inline SCM
scm_atomic_ref_scm (SCM *loc)
{
atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
return SCM_PACK (atomic_load (a_loc));
}
static inline SCM
scm_atomic_swap_scm (SCM *loc, SCM val)
{
atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
return SCM_PACK (atomic_exchange (a_loc, SCM_UNPACK (val)));
}
static inline SCM
scm_atomic_compare_and_swap_scm (SCM *loc, SCM expected, SCM desired)
{
atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
SCM result = expected;
atomic_compare_exchange_strong (a_loc, (uintptr_t *) &result,
SCM_UNPACK (desired));
return result;
}
#else /* HAVE_STDATOMIC_H */
/* Fallback implementation using locks. */
#include "libguile/threads.h"
static scm_i_pthread_mutex_t atomics_lock = SCM_I_PTHREAD_MUTEX_INITIALIZER;
static inline uint32_t
scm_atomic_subtract_uint32 (uint32_t *loc, uint32_t arg)
{
uint32_t ret;
scm_i_pthread_mutex_lock (&atomics_lock);
ret = *loc;
*loc -= arg;
scm_i_pthread_mutex_unlock (&atomics_lock);
return ret;
}
static inline int
scm_atomic_compare_and_swap_uint32 (uint32_t *loc, uint32_t *expected,
uint32_t desired)
{
int ret;
scm_i_pthread_mutex_lock (&atomics_lock);
if (*loc == *expected)
{
*loc = desired;
ret = 1;
}
else
{
*expected = *loc;
ret = 0;
}
scm_i_pthread_mutex_unlock (&atomics_lock);
return ret;
}
static inline void
scm_atomic_set_pointer (void **loc, void *val)
{
scm_i_pthread_mutex_lock (&atomics_lock);
*loc = val;
scm_i_pthread_mutex_unlock (&atomics_lock);
}
static inline void *
scm_atomic_ref_pointer (void **loc)
{
void *ret;
scm_i_pthread_mutex_lock (&atomics_lock);
ret = *loc;
scm_i_pthread_mutex_unlock (&atomics_lock);
return ret;
}
static inline void
scm_atomic_set_scm (SCM *loc, SCM val)
{
scm_i_pthread_mutex_lock (&atomics_lock);
*loc = val;
scm_i_pthread_mutex_unlock (&atomics_lock);
}
static inline SCM
scm_atomic_ref_scm (SCM *loc)
{
SCM ret;
scm_i_pthread_mutex_lock (&atomics_lock);
ret = *loc;
scm_i_pthread_mutex_unlock (&atomics_lock);
return ret;
}
static inline SCM
scm_atomic_swap_scm (SCM *loc, SCM val)
{
SCM ret;
scm_i_pthread_mutex_lock (&atomics_lock);
ret = *loc;
*loc = val;
scm_i_pthread_mutex_unlock (&atomics_lock);
return ret;
}
static inline SCM
scm_atomic_compare_and_swap_scm (SCM *loc, SCM expected, SCM desired)
{
SCM ret;
scm_i_pthread_mutex_lock (&atomics_lock);
if (*loc == expected)
{
*loc = desired;
ret = expected;
}
else
{
ret = *loc;
}
scm_i_pthread_mutex_unlock (&atomics_lock);
return ret;
}
#endif /* HAVE_STDATOMIC_H */
#endif /* SCM_ATOMICS_INTERNAL_H */
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