2 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
9 #ifndef HEADER_INTERNAL_REFCOUNT_H
10 # define HEADER_INTERNAL_REFCOUNT_H
12 # if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \
13 && !defined(__STDC_NO_ATOMICS__)
14 # include <stdatomic.h>
15 # define HAVE_C11_ATOMICS
18 # if defined(HAVE_C11_ATOMICS) && defined(ATOMIC_INT_LOCK_FREE) \
19 && ATOMIC_INT_LOCK_FREE > 0
21 # define HAVE_ATOMICS 1
23 typedef _Atomic int CRYPTO_REF_COUNT;
25 static ossl_inline int CRYPTO_GET_REF(_Atomic int *val, int *ret, void *lock)
27 *ret = atomic_fetch_add_explicit(val, 0, memory_order_relaxed);
31 static ossl_inline int CRYPTO_UP_REF(_Atomic int *val, int *ret, void *lock)
33 *ret = atomic_fetch_add_explicit(val, 1, memory_order_relaxed) + 1;
37 static ossl_inline int CRYPTO_DOWN_REF(_Atomic int *val, int *ret, void *lock)
39 *ret = atomic_fetch_sub_explicit(val, 1, memory_order_release) - 1;
41 atomic_thread_fence(memory_order_acquire);
45 # elif defined(__GNUC__) && defined(__ATOMIC_RELAXED) && __GCC_ATOMIC_INT_LOCK_FREE > 0
47 # define HAVE_ATOMICS 1
49 typedef int CRYPTO_REF_COUNT;
51 static ossl_inline int CRYPTO_GET_REF(_Atomic int *val, int *ret, void *lock)
53 *ret = __atomic_fetch_add(val, 0, __ATOMIC_RELAXED);
57 static ossl_inline int CRYPTO_UP_REF(int *val, int *ret, void *lock)
59 *ret = __atomic_fetch_add(val, 1, __ATOMIC_RELAXED) + 1;
63 static ossl_inline int CRYPTO_DOWN_REF(int *val, int *ret, void *lock)
65 *ret = __atomic_fetch_sub(val, 1, __ATOMIC_RELEASE) - 1;
67 __atomic_thread_fence(__ATOMIC_ACQUIRE);
73 typedef int CRYPTO_REF_COUNT;
75 # define CRYPTO_GET_REF(val, ret, lock) CRYPTO_atomic_add(val, 0, ret, lock)
76 # define CRYPTO_UP_REF(val, ret, lock) CRYPTO_atomic_add(val, 1, ret, lock)
77 # define CRYPTO_DOWN_REF(val, ret, lock) CRYPTO_atomic_add(val, -1, ret, lock)