libmemif: refactor examples

- icmp_responder: responds to ICMPv4 and ARP requests
- loopback: connects two interfaces and sends a
  verification packet from master memif to slave memif
  where it is looped back
- loopback (reverse path): reverses direction of packet
  in loopback application (slave memif to master memif)

Type: refactor

Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
Change-Id: Ie90aaa3367269408efb6c5d538ad5aa827432238
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/extras/libmemif/examples/common/packet_handler.c b/extras/libmemif/examples/common/packet_handler.c
new file mode 100644
index 00000000000..705cc728a36
--- /dev/null
+++ b/extras/libmemif/examples/common/packet_handler.c
@@ -0,0 +1,65 @@
+/*
+ *------------------------------------------------------------------
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * 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.
+ *------------------------------------------------------------------
+ */
+
+#include <common.h>
+#include <icmp_proto.h>
+
+/* reply with the same data */
+int
+basic_packet_handler (memif_connection_t *c)
+{
+  int i;
+  memif_buffer_t *dest, *src;
+
+  /* in case of zero-copy the tx_buf_num will be zero, so the loop body won't
+   * execute */
+  for (i = 0; i < c->tx_buf_num; i++)
+    {
+      memcpy (c->tx_bufs[i].data, c->rx_bufs[i].data, c->rx_bufs[i].len);
+    }
+
+  return 0;
+}
+
+/* ICMPv4 and ARP handler */
+int
+icmp_packet_handler (memif_connection_t *c)
+{
+  int i;
+  memif_buffer_t *dest, *src;
+
+  /* if tx_buf_num > 0 we use non-zero-copy mode */
+  if (c->tx_buf_num > 0)
+    {
+      for (i = 0; i < c->tx_buf_num; i++)
+	{
+	  resolve_packet (c->rx_bufs[i].data, c->rx_bufs[i].len,
+			  c->tx_bufs[i].data, &c->tx_bufs[i].len, c->ip_addr,
+			  c->hw_addr);
+	}
+    }
+  else
+    {
+      for (i = 0; i < c->rx_buf_num; i++)
+	{
+	  resolve_packet_zero_copy (c->rx_bufs[i].data, &c->rx_bufs[i].len,
+				    c->ip_addr, c->hw_addr);
+	}
+    }
+
+  return 0;
+}
\ No newline at end of file