1/* Copyright (c) 2015, Google Inc.
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14
15#include "internal.h"
16
17#include <stdlib.h>
18
19#include <openssl/type_check.h>
20
21
22#if !defined(OPENSSL_C11_ATOMIC)
23
24OPENSSL_COMPILE_ASSERT((CRYPTO_refcount_t)-1 == CRYPTO_REFCOUNT_MAX,
25                       CRYPTO_REFCOUNT_MAX_is_incorrect);
26
27static struct CRYPTO_STATIC_MUTEX g_refcount_lock = CRYPTO_STATIC_MUTEX_INIT;
28
29void CRYPTO_refcount_inc(CRYPTO_refcount_t *count) {
30  CRYPTO_STATIC_MUTEX_lock_write(&g_refcount_lock);
31  if (*count < CRYPTO_REFCOUNT_MAX) {
32    (*count)++;
33  }
34  CRYPTO_STATIC_MUTEX_unlock_write(&g_refcount_lock);
35}
36
37int CRYPTO_refcount_dec_and_test_zero(CRYPTO_refcount_t *count) {
38  int ret;
39
40  CRYPTO_STATIC_MUTEX_lock_write(&g_refcount_lock);
41  if (*count == 0) {
42    abort();
43  }
44  if (*count < CRYPTO_REFCOUNT_MAX) {
45    (*count)--;
46  }
47  ret = (*count == 0);
48  CRYPTO_STATIC_MUTEX_unlock_write(&g_refcount_lock);
49
50  return ret;
51}
52
53#endif  /* OPENSSL_C11_ATOMIC */
54