From c1aa211dc757bc46e07f27e5ff527e037eafc03d Mon Sep 17 00:00:00 2001
From: Matthias Kovatsch <kovatsch@inf.ethz.ch>
Date: Wed, 1 Feb 2012 03:58:35 +0100
Subject: [PATCH] Added RST-MID matching for observing.

---
 apps/er-coap-07/er-coap-07-engine.c    |  4 ++--
 apps/er-coap-07/er-coap-07-observing.c | 24 ++++++++++++++++++++++++
 apps/er-coap-07/er-coap-07-observing.h |  2 ++
 3 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/apps/er-coap-07/er-coap-07-engine.c b/apps/er-coap-07/er-coap-07-engine.c
index f0545d61e..326d811a9 100644
--- a/apps/er-coap-07/er-coap-07-engine.c
+++ b/apps/er-coap-07/er-coap-07-engine.c
@@ -225,8 +225,8 @@ handle_incoming_data(void)
           /* Cancel possible subscriptions. */
           if (IS_OPTION(message, COAP_OPTION_TOKEN))
           {
-            /* RST must be empty, so it is a full client reset. */
-            coap_remove_observer_by_client(&UIP_IP_BUF->srcipaddr, UIP_UDP_BUF->srcport);
+            /* Erbium stores last MID for each observer. */
+            coap_remove_observer_by_mid(&UIP_IP_BUF->srcipaddr, UIP_UDP_BUF->srcport, message->mid);
           }
         }
 
diff --git a/apps/er-coap-07/er-coap-07-observing.c b/apps/er-coap-07/er-coap-07-observing.c
index 5324a3a00..d9852f4e0 100644
--- a/apps/er-coap-07/er-coap-07-observing.c
+++ b/apps/er-coap-07/er-coap-07-observing.c
@@ -69,6 +69,7 @@ coap_add_observer(uip_ipaddr_t *addr, uint16_t port, const uint8_t *token, size_
     o->port = port;
     o->token_len = token_len;
     memcpy(o->token, token, token_len);
+    o->last_mid = 0;
 
     stimer_set(&o->refresh_timer, COAP_OBSERVING_REFRESH_INTERVAL);
 
@@ -107,6 +108,7 @@ coap_remove_observer_by_client(uip_ipaddr_t *addr, uint16_t port)
   }
   return removed;
 }
+
 int
 coap_remove_observer_by_token(uip_ipaddr_t *addr, uint16_t port, uint8_t *token, size_t token_len)
 {
@@ -124,6 +126,7 @@ coap_remove_observer_by_token(uip_ipaddr_t *addr, uint16_t port, uint8_t *token,
   }
   return removed;
 }
+
 int
 coap_remove_observer_by_url(uip_ipaddr_t *addr, uint16_t port, const char *url)
 {
@@ -141,6 +144,24 @@ coap_remove_observer_by_url(uip_ipaddr_t *addr, uint16_t port, const char *url)
   }
   return removed;
 }
+
+int
+coap_remove_observer_by_mid(uip_ipaddr_t *addr, uint16_t port, uint16_t mid)
+{
+  int removed = 0;
+  coap_observer_t* obs = NULL;
+
+  for (obs = (coap_observer_t*)list_head(observers_list); obs; obs = obs->next)
+  {
+    PRINTF("Remove check URL %p\n", url);
+    if (uip_ipaddr_cmp(&obs->addr, addr) && obs->port==port && obs->last_mid==mid)
+    {
+      coap_remove_observer(obs);
+      removed++;
+    }
+  }
+  return removed;
+}
 /*-----------------------------------------------------------------------------------*/
 void
 coap_notify_observers(const char *url, int type, uint32_t observe, uint8_t *payload, size_t payload_len)
@@ -177,6 +198,9 @@ coap_notify_observers(const char *url, int type, uint32_t observe, uint8_t *payl
         PRINTF(":%u\n", obs->port);
         PRINTF("  %.*s\n", payload_len, payload);
 
+        /* Update last MID for RST matching. */
+        obs->last_mid = transaction->mid;
+
         coap_send_transaction(transaction);
       }
     }
diff --git a/apps/er-coap-07/er-coap-07-observing.h b/apps/er-coap-07/er-coap-07-observing.h
index d30acbebc..7b09ba83e 100644
--- a/apps/er-coap-07/er-coap-07-observing.h
+++ b/apps/er-coap-07/er-coap-07-observing.h
@@ -61,6 +61,7 @@ typedef struct coap_observer {
   uint16_t port;
   uint8_t token_len;
   uint8_t token[COAP_TOKEN_LEN];
+  uint16_t last_mid;
   struct stimer refresh_timer;
 } coap_observer_t;
 
@@ -72,6 +73,7 @@ void coap_remove_observer(coap_observer_t *o);
 int coap_remove_observer_by_client(uip_ipaddr_t *addr, uint16_t port);
 int coap_remove_observer_by_token(uip_ipaddr_t *addr, uint16_t port, uint8_t *token, size_t token_len);
 int coap_remove_observer_by_url(uip_ipaddr_t *addr, uint16_t port, const char *url);
+int coap_remove_observer_by_mid(uip_ipaddr_t *addr, uint16_t port, uint16_t mid);
 
 void coap_notify_observers(const char *url, int type, uint32_t observe, uint8_t *payload, size_t payload_len);