+#ifndef _URCU_FUTEX_H
+#define _URCU_FUTEX_H
+
+/*
+ * urcu-futex.h
+ *
+ * Userspace RCU - sys_futex/compat_futex header.
+ *
+ * This 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 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 library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <urcu/config.h>
+
+#define FUTEX_WAIT 0
+#define FUTEX_WAKE 1
+
+/*
+ * sys_futex compatibility header.
+ * Use *only* *either of* futex_noasync OR futex_async on a given address.
+ *
+ * futex_noasync cannot be executed in signal handlers, but ensures that
+ * it will be put in a wait queue even in compatibility mode.
+ *
+ * futex_async is signal-handler safe for the wakeup. It uses polling
+ * on the wait-side in compatibility mode.
+ */
+
+#ifdef CONFIG_URCU_HAVE_FUTEX
+#include <sys/syscall.h>
+#define futex(...) syscall(__NR_futex, __VA_ARGS__)
+#define futex_noasync(uaddr, op, val, timeout, uaddr2, val3) \
+ futex(uaddr, op, val, timeout, uaddr2, val3)
+#define futex_async(uaddr, op, val, timeout, uaddr2, val3) \
+ futex(uaddr, op, val, timeout, uaddr2, val3)
+#else
+extern int compat_futex_noasync(int *uaddr, int op, int val,
+ const struct timespec *timeout, int *uaddr2, int val3);
+#define futex_noasync(uaddr, op, val, timeout, uaddr2, val3) \
+ compat_futex_noasync(uaddr, op, val, timeout, uaddr2, val3)
+extern int compat_futex_async(int *uaddr, int op, int val,
+ const struct timespec *timeout, int *uaddr2, int val3);
+#define futex_async(uaddr, op, val, timeout, uaddr2, val3) \
+ compat_futex_async(uaddr, op, val, timeout, uaddr2, val3)
+#endif
+
+#endif /* _URCU_FUTEX_H */