net: Add batman-adv meshing protocol

B.A.T.M.A.N. (better approach to mobile ad-hoc networking) is a routing
protocol for multi-hop ad-hoc mesh networks. The networks may be wired or
wireless. See http://www.open-mesh.org/ for more information and user space
tools.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/batman-adv/ring_buffer.c b/net/batman-adv/ring_buffer.c
new file mode 100644
index 0000000..defd37c
--- /dev/null
+++ b/net/batman-adv/ring_buffer.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2007-2010 B.A.T.M.A.N. contributors:
+ *
+ * Marek Lindner
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ *
+ */
+
+#include "main.h"
+#include "ring_buffer.h"
+
+void ring_buffer_set(uint8_t lq_recv[], uint8_t *lq_index, uint8_t value)
+{
+	lq_recv[*lq_index] = value;
+	*lq_index = (*lq_index + 1) % TQ_GLOBAL_WINDOW_SIZE;
+}
+
+uint8_t ring_buffer_avg(uint8_t lq_recv[])
+{
+	uint8_t *ptr;
+	uint16_t count = 0, i = 0, sum = 0;
+
+	ptr = lq_recv;
+
+	while (i < TQ_GLOBAL_WINDOW_SIZE) {
+		if (*ptr != 0) {
+			count++;
+			sum += *ptr;
+		}
+
+		i++;
+		ptr++;
+	}
+
+	if (count == 0)
+		return 0;
+
+	return (uint8_t)(sum / count);
+}