Add atomic write call

[openssl.git] / crypto / threads_pthread.c

diff --git a/crypto/threads_pthread.c b/crypto/threads_pthread.c
index e28a2021b45a76fb72675b2069b58956a67bbe92..34be314f1fd7cbb4bcff27c1cc4d85c0034ca1a4 100644 (file)
--- a/crypto/threads_pthread.c
+++ b/crypto/threads_pthread.c
@@ -169,11 +169,58 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
     return 1;
 }
 
+int CRYPTO_atomic_read(int *val, int *ret, CRYPTO_RWLOCK *lock)
+{
+# if defined(__GNUC__) && defined(__ATOMIC_ACQUIRE)
+    if (__atomic_is_lock_free(sizeof(*val), val)) {
+        __atomic_load(val, ret, __ATOMIC_ACQUIRE);
+        return 1;
+    }
+# endif
+    if (!CRYPTO_THREAD_write_lock(lock))
+        return 0;
+
+    *ret  = *val;
+
+    if (!CRYPTO_THREAD_unlock(lock))
+        return 0;
+
+    return 1;
+}
+
+int CRYPTO_atomic_write(int *val, int n, CRYPTO_RWLOCK *lock)
+{
+# if defined(__GNUC__) && defined(__ATOMIC_RELEASE)
+    if (__atomic_is_lock_free(sizeof(*val), val)) {
+        __atomic_store(val, &n, __ATOMIC_RELEASE);
+        return 1;
+    }
+# endif
+    if (!CRYPTO_THREAD_write_lock(lock))
+        return 0;
+
+    *val = n;
+
+    if (!CRYPTO_THREAD_unlock(lock))
+        return 0;
+
+    return 1;
+}
+
+# ifdef OPENSSL_SYS_UNIX
+static pthread_once_t fork_once_control = PTHREAD_ONCE_INIT;
+
+static void fork_once_func(void)
+{
+    pthread_atfork(OPENSSL_fork_prepare,
+                   OPENSSL_fork_parent, OPENSSL_fork_child);
+}
+# endif
+
 int openssl_init_fork_handlers(void)
 {
 # ifdef OPENSSL_SYS_UNIX
-    if (pthread_atfork(OPENSSL_fork_prepare,
-                       OPENSSL_fork_parent, OPENSSL_fork_child) == 0)
+    if (pthread_once(&fork_once_control, fork_once_func) == 0)
         return 1;
 # endif
     return 0;