Index: libc/generic/futex.c
===================================================================
--- libc/generic/futex.c	(revision 1cef26f9d6e131b2ba3f253bc6c01cd332b49790)
+++ libc/generic/futex.c	(revision 1cef26f9d6e131b2ba3f253bc6c01cd332b49790)
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2006 Jakub Jermar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */ 
+
+#include <futex.h>
+#include <atomic.h>
+#include <libc.h>
+#include <stdio.h>
+
+void futex_initialize(atomic_t *futex, int val)
+{
+	atomic_set(futex, val);
+}
+
+int futex_down(atomic_t *futex)
+{
+	long val;
+	
+	val = atomic_predec(futex);
+	if (val < 0)
+		return __SYSCALL1(SYS_FUTEX_SLEEP, (sysarg_t) &futex->count);
+		
+	return 0;
+}
+
+int futex_up(atomic_t *futex)
+{
+	if (atomic_preinc(futex) == 0)
+		return __SYSCALL1(SYS_FUTEX_WAKEUP, (sysarg_t) &futex->count);
+		
+	return 0;
+}