Introduced atomic.h to simplify handling of atomic integers

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

1 files changed, 81 insertions, 0 deletions

diff --git a/lib/atomic.h b/lib/atomic.h
new file mode 100644
index 0000000000..3e943a81b8
--- /dev/null
+++ b/lib/atomic.h
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2017 Red Hat, Inc.
+ *
+ * Author: Nikos Mavrogiannopoulos
+ *
+ * This file is part of GnuTLS.
+ *
+ * The GnuTLS 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 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library 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 this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+#ifndef GNUTLS_ATOMIC_H
+#define GNUTLS_ATOMIC_H
+
+#ifdef HAVE_STDATOMIC_H
+# include <stdatomic.h>
+
+# define gnutls_atomic_uint_t atomic_uint
+# define DEF_ATOMIC_INT(x) atomic_uint x
+# define gnutls_atomic_increment(x) (*x)++
+# define gnutls_atomic_decrement(x) (*x)--
+# define gnutls_atomic_init(x) (*x)=(0)
+# define gnutls_atomic_deinit(x)
+# define gnutls_atomic_val(x) (*x)
+#else
+# include "locks.h"
+
+struct gnutls_atomic_uint_st {
+	void *lock;
+	unsigned int value;
+};
+typedef struct gnutls_atomic_uint_st *gnutls_atomic_uint_t;
+
+# define DEF_ATOMIC_INT(x) struct gnutls_atomic_uint_st x
+
+inline static unsigned gnutls_atomic_val(gnutls_atomic_uint_t x)
+{
+	unsigned int t;
+	gnutls_mutex_lock(x->lock);
+	t = x->value;
+	gnutls_mutex_unlock(x->lock);
+	return t;
+}
+
+inline static void gnutls_atomic_increment(gnutls_atomic_uint_t x)
+{
+	gnutls_mutex_lock(x->lock);
+	x->value++;
+	gnutls_mutex_unlock(x->lock);
+}
+
+inline static void gnutls_atomic_decrement(gnutls_atomic_uint_t x)
+{
+	gnutls_mutex_lock(x->lock);
+	x->value--;
+	gnutls_mutex_unlock(x->lock);
+}
+
+inline static void gnutls_atomic_init(gnutls_atomic_uint_t x)
+{
+	gnutls_mutex_init(&x->lock);
+	x->value = 0;
+}
+inline static void gnutls_atomic_deinit(gnutls_atomic_uint_t x)
+{
+	gnutls_mutex_deinit(&x->lock);
+}
+#endif
+
+#endif