FPM component that can decode routes from Quagga's FIB push interface.
Change-Id: I57bfd9273b81c8d368a59a3acea53486cb4acfc1
diff --git a/apps/routing/src/main/java/org/onosproject/routing/fpm/FpmFrameDecoder.java b/apps/routing/src/main/java/org/onosproject/routing/fpm/FpmFrameDecoder.java
new file mode 100644
index 0000000..9ecad04
--- /dev/null
+++ b/apps/routing/src/main/java/org/onosproject/routing/fpm/FpmFrameDecoder.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.routing.fpm;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.channel.Channel;
+import org.jboss.netty.channel.ChannelHandlerContext;
+import org.jboss.netty.handler.codec.frame.FrameDecoder;
+import org.onosproject.routing.fpm.protocol.FpmHeader;
+
+/**
+ * Frame decoder for FPM connections.
+ */
+public class FpmFrameDecoder extends FrameDecoder {
+
+ @Override
+ protected Object decode(ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer)
+ throws Exception {
+
+ if (!channel.isConnected()) {
+ return null;
+ }
+
+ if (buffer.readableBytes() < FpmHeader.FPM_HEADER_LENGTH) {
+ return null;
+ }
+
+ buffer.markReaderIndex();
+
+ short version = buffer.readUnsignedByte();
+ short type = buffer.readUnsignedByte();
+ int length = buffer.readUnsignedShort();
+
+ buffer.resetReaderIndex();
+
+ if (buffer.readableBytes() < length) {
+ // Not enough bytes to read a whole message
+ return null;
+ }
+
+ byte[] fpmMessage = new byte[length];
+ buffer.readBytes(fpmMessage);
+
+ return FpmHeader.decode(fpmMessage, 0, fpmMessage.length);
+ }
+}