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+/* This header supplies atomic operations. So far, we rely on GCC's
+ * atomic builtins. I have no idea if we can check them via autotools,
+ * but I am making the necessary provisioning to live without them if
+ * they are not available. Please note that you should only use the macros
+ * here if you think you can actually live WITHOUT an explicit atomic operation,
+ * because in the non-presence of them, we simply do it without atomicitiy.
+ * Which, for word-aligned data types, usually (but only usually!) should work.
+ *
+ * We are using the functions described in
+ * http:/gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html
+ *
+ * THESE MACROS MUST ONLY BE USED WITH WORD-SIZED DATA TYPES!
+ *
+ * Copyright 2008 Rainer Gerhards and Adiscon GmbH.
+ *
+ * This file is part of the rsyslog runtime library.
+ *
+ * The rsyslog runtime library 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * The rsyslog runtime 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 the rsyslog runtime library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * A copy of the GPL can be found in the file "COPYING" in this distribution.
+ * A copy of the LGPL can be found in the file "COPYING.LESSER" in this distribution.
+ */
+#include "config.h" /* autotools! */
+
+#ifndef INCLUDED_ATOMIC_H
+#define INCLUDED_ATOMIC_H
+
+/* set the following to 1 if we have atomic operations (and #undef it otherwise) */
+/* #define DO_HAVE_ATOMICS 1 */
+/* for this release, we disable atomic calls because there seem to be some
+ * portability problems and we can not fix that without destabilizing the build.
+ * They simply came in too late. -- rgerhards, 2008-04-02
+ */
+/* make sure they are not used!
+#define ATOMIC_INC(data) ((void) __sync_fetch_and_add(&data, 1))
+#define ATOMIC_DEC_AND_FETCH(data) __sync_sub_and_fetch(&data, 1)
+*/
+#define ATOMIC_INC(data) (++(data))
+
+#endif /* #ifndef INCLUDED_ATOMIC_H */