p99_atomic_flag.h

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/* This may look like nonsense, but it really is -*- mode: C; coding: utf-8 -*- */
/*                                                                              */
/* Except for parts copied from previous work and as explicitly stated below,   */
/* the author and copyright holder for this work is                             */
/* (C) copyright  2013 Jens Gustedt, INRIA, France                              */
/*                                                                              */
/* This file is free software; it is part of the P99 project.                   */
/*                                                                              */
/* Licensed under the Apache License, Version 2.0 (the "License");              */
/* you may not use this file except in compliance with the License.             */
/* You may obtain a copy of the License at                                      */
/*                                                                              */
/*     http://www.apache.org/licenses/LICENSE-2.0                               */
/*                                                                              */
/* Unless required by applicable law or agreed to in writing, software          */
/* distributed under the License is distributed on an "AS IS" BASIS,            */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.     */
/* See the License for the specific language governing permissions and          */
/* limitations under the License.                                               */
/*                                                                              */
#ifndef P99_ATOMIC_FLAG_H_
#define P99_ATOMIC_FLAG_H_ 1
 
p99_inline
void atomic_flag_lock(volatile atomic_flag *p00_objp) {
  while (atomic_flag_test_and_set_explicit(p00_objp, memory_order_acquire));
}
 
p99_inline
_Bool atomic_flag_trylock(volatile atomic_flag *p00_objp) {
  return !atomic_flag_test_and_set_explicit(p00_objp, memory_order_acquire);
}
 
p99_inline
void atomic_flag_unlock(volatile atomic_flag *p00_objp) {
  atomic_flag_clear_explicit(p00_objp, memory_order_release);
}
 
#define P99_SPIN_EXCLUDE(FLAGP)   P00_SPIN_EXCLUDE(FLAGP, P99_UNIQ(flg))
 
#define P00_SPIN_EXCLUDE(FLAGP, ID)                            \
P00_BLK_START                                                  \
P00_BLK_DECL(register atomic_flag volatile*const, ID, (FLAGP)) \
P00_BLK_BEFAFT(atomic_flag_lock(ID),                           \
               atomic_flag_unlock(ID))                         \
P00_BLK_END
 
#endif