er-coap: separate the communication layer

This code was copied and adapted from: https://github.com/cetic/6lbr
Licensed under the same license as Contiki.

apps/er-coap/Makefile.er-coap

@@ -4,3 +4,5 @@ er-coap_src = er-coap.c er-coap-engine.c er-coap-transactions.c      \
 
 # Erbium will implement the REST Engine
 CFLAGS += -DREST=coap_rest_implementation
+
+er-coap_src += er-coap-udp.c

apps/er-coap/er-coap-communication.h

@@ -0,0 +1,15 @@
+#ifndef _ER_COAP_COMMUNICATION_H_
+#define _ER_COAP_COMMUNICATION_H_
+
+#include "contiki.h"
+
+void
+coap_init_communication_layer(uint16_t port);
+
+void
+coap_send_message(uip_ipaddr_t *addr, uint16_t port, uint8_t *data, uint16_t length);
+
+void
+coap_handle_receive(void);
+
+#endif

apps/er-coap/er-coap-engine.c

@@ -41,6 +41,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include "er-coap-engine.h"
+#include "er-coap-communication.h"
 
 #define DEBUG 0
 #if DEBUG
@@ -64,8 +65,8 @@ static service_callback_t service_cbk = NULL;
 /*---------------------------------------------------------------------------*/
 /*- Internal API ------------------------------------------------------------*/
 /*---------------------------------------------------------------------------*/
-static int
+int
-coap_receive(void)
+coap_receive()
 {
   erbium_status_code = NO_ERROR;
 
@@ -346,7 +347,7 @@ PROCESS_THREAD(coap_engine, ev, data)
     PROCESS_YIELD();
 
     if(ev == tcpip_event) {
-      coap_receive();
+      coap_handle_receive();
     } else if(ev == PROCESS_EVENT_TIMER) {
       /* retransmissions are handled here */
       coap_check_transactions();

apps/er-coap/er-coap-engine.h

@@ -52,6 +52,7 @@ typedef coap_packet_t rest_request_t;
 typedef coap_packet_t rest_response_t;
 
 void coap_init_engine(void);
+int coap_receive();
 
 /*---------------------------------------------------------------------------*/
 /*- Client Part -------------------------------------------------------------*/

apps/er-coap/er-coap-udp.c

@@ -0,0 +1,42 @@
+#include "contiki.h"
+#include "contiki-net.h"
+#include "er-coap-engine.h"
+#include "er-coap-communication.h"
+
+#include <string.h>
+
+#define DEBUG DEBUG_NONE
+#include "uip-debug.h"
+
+static struct uip_udp_conn *udp_conn = NULL;
+
+/*-----------------------------------------------------------------------------------*/
+void
+coap_init_communication_layer(uint16_t port)
+{
+  /* new connection with remote host */
+  udp_conn = udp_new(NULL, 0, NULL);
+  udp_bind(udp_conn, port);
+  PRINTF("Listening on port %u\n", uip_ntohs(udp_conn->lport));
+}
+/*-----------------------------------------------------------------------------------*/
+void
+coap_send_message(uip_ipaddr_t *addr, uint16_t port, uint8_t *data, uint16_t length)
+{
+  /* Configure connection to reply to client */
+  uip_ipaddr_copy(&udp_conn->ripaddr, addr);
+  udp_conn->rport = port;
+
+  uip_udp_packet_send(udp_conn, data, length);
+  PRINTF("-sent UDP datagram (%u)-\n", length);
+
+  /* Restore server connection to allow data from any node */
+  memset(&udp_conn->ripaddr, 0, sizeof(udp_conn->ripaddr));
+  udp_conn->rport = 0;
+}
+/*-----------------------------------------------------------------------------------*/
+void
+coap_handle_receive()
+{
+  coap_receive();
+}

apps/er-coap/er-coap.c

@@ -44,6 +44,7 @@
 
 #include "er-coap.h"
 #include "er-coap-transactions.h"
+#include "er-coap-communication.h"
 
 #define DEBUG 0
 #if DEBUG
@@ -60,7 +61,6 @@
 /*---------------------------------------------------------------------------*/
 /*- Variables ---------------------------------------------------------------*/
 /*---------------------------------------------------------------------------*/
-static struct uip_udp_conn *udp_conn = NULL;
 static uint16_t current_mid = 0;
 
 coap_status_t erbium_status_code = NO_ERROR;
@@ -279,9 +279,7 @@ void
 coap_init_connection(uint16_t port)
 {
   /* new connection with remote host */
-  udp_conn = udp_new(NULL, 0, NULL);
+  coap_init_communication_layer(port);
-  udp_bind(udp_conn, port);
-  PRINTF("Listening on port %u\n", uip_ntohs(udp_conn->lport));
 
   /* initialize transaction ID */
   current_mid = random_rand();
@@ -422,23 +420,6 @@ coap_serialize_message(void *packet, uint8_t *buffer)
   return (option - buffer) + coap_pkt->payload_len; /* packet length */
 }
 /*---------------------------------------------------------------------------*/
-void
-coap_send_message(uip_ipaddr_t *addr, uint16_t port, uint8_t *data,
-                  uint16_t length)
-{
-  /* configure connection to reply to client */
-  uip_ipaddr_copy(&udp_conn->ripaddr, addr);
-  udp_conn->rport = port;
-
-  uip_udp_packet_send(udp_conn, data, length);
-
-  PRINTF("-sent UDP datagram (%u)-\n", length);
-
-  /* restore server socket to allow data from any node */
-  memset(&udp_conn->ripaddr, 0, sizeof(udp_conn->ripaddr));
-  udp_conn->rport = 0;
-}
-/*---------------------------------------------------------------------------*/
 coap_status_t
 coap_parse_message(void *packet, uint8_t *data, uint16_t data_len)
 {