-nack support

3 files changed, 48 insertions, 14 deletions

diff --git a/src/dv/dv.h b/src/dv/dv.h
index bcc586a0e..c0247218e 100644
--- a/src/dv/dv.h
+++ b/src/dv/dv.h
@@ -135,12 +135,13 @@ struct GNUNET_DV_SendMessage
 
 /**
  * Message from service to DV plugin, saying that a
- * SEND request was handled.  
+ * SEND request was handled.
  */
 struct GNUNET_DV_AckMessage
 {
   /**
-   * Type: GNUNET_MESSAGE_TYPE_DV_SEND_ACK
+   * Type: GNUNET_MESSAGE_TYPE_DV_SEND_ACK or
+   * GNUNET_MESSAGE_TYPE_DV_SEND_NACK.
    */ 
   struct GNUNET_MessageHeader header;
 
@@ -155,6 +156,32 @@ struct GNUNET_DV_AckMessage
   struct GNUNET_PeerIdentity target;
 
 };
+
+
+/**
+ * Message from service to DV plugin, saying that our
+ * distance to another peer changed.
+ */
+struct GNUNET_DV_DistanceUpdateMessage
+{
+  /**
+   * Type: GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED.
+   */ 
+  struct GNUNET_MessageHeader header;
+
+  /**
+   * What is the new distance?
+   */
+  uint32_t distance GNUNET_PACKED;
+
+  /**
+   * The peer for which the distance changed.
+   */
+  struct GNUNET_PeerIdentity peer;
+
+};
+
+
 GNUNET_NETWORK_STRUCT_END
 
 #endif
diff --git a/src/dv/dv_api.c b/src/dv/dv_api.c
index fff0896b3..dab7c7ad3 100644
--- a/src/dv/dv_api.c
+++ b/src/dv/dv_api.c
@@ -266,9 +266,10 @@ process_ack (void *cls,
                  GNUNET_CONTAINER_multihashmap_remove (ctx->sh->send_callbacks,
                                                        key,
                                                        th));
-  /* FIXME: should distinguish between success and failure here... */
   th->cb (th->cb_cls,
-          GNUNET_OK);
+          (ntohs (ctx->ack->header.type) == GNUNET_MESSAGE_TYPE_DV_SEND_ACK)
+          ? GNUNET_OK
+          : GNUNET_SYSERR);
   GNUNET_free (th);
   return GNUNET_NO;
 }
@@ -345,6 +346,7 @@ handle_message_receipt (void *cls,
                     payload);
     break;
   case GNUNET_MESSAGE_TYPE_DV_SEND_ACK:
+  case GNUNET_MESSAGE_TYPE_DV_SEND_NACK:
     if (ntohs (msg->size) != sizeof (struct GNUNET_DV_AckMessage))
     {
       GNUNET_break (0);
@@ -358,7 +360,10 @@ handle_message_receipt (void *cls,
                                                 &ack->target.hashPubKey,
                                                 &process_ack,
                                                 &ctx);
-    return;
+    break;
+  case GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED:
+    GNUNET_break (0);
+    break;
   default:
     reconnect (sh);
     break;
diff --git a/src/dv/gnunet-service-dv.c b/src/dv/gnunet-service-dv.c
index fafccb7f3..e6c107981 100644
--- a/src/dv/gnunet-service-dv.c
+++ b/src/dv/gnunet-service-dv.c
@@ -30,8 +30,6 @@
  * TODO:
  * - distance updates are not properly communicate to US by core,
  *   and conversely we don't give distance updates properly to the plugin yet
- * - we send 'ACK' even if a message was dropped due to no route (may
- *   be harmless, but should at least be documented -- or support NACK)
  */
 #include "platform.h"
 #include "gnunet_util_lib.h"
@@ -503,14 +501,16 @@ send_control_to_plugin (const struct GNUNET_MessageHeader *message)
 
 
 /**
- * Give an ACK message to the plugin, we transmitted a message for it.
+ * Give an (N)ACK message to the plugin, we transmitted a message for it.
  *
  * @param target peer that received the message
  * @param uid plugin-chosen UID for the message
+ * @param nack GNUNET_NO to send ACK, GNUNET_YES to send NACK
  */
 static void
 send_ack_to_plugin (const struct GNUNET_PeerIdentity *target, 
-                    uint32_t uid)
+                    uint32_t uid,
+                    int nack)
 {
   struct GNUNET_DV_AckMessage ack_msg;
 
@@ -518,7 +518,9 @@ send_ack_to_plugin (const struct GNUNET_PeerIdentity *target,
               "Delivering ACK for message to peer `%s'\n",
               GNUNET_i2s (target));
   ack_msg.header.size = htons (sizeof (ack_msg));
-  ack_msg.header.type = htons (GNUNET_MESSAGE_TYPE_DV_SEND_ACK);
+  ack_msg.header.type = htons ((GNUNET_YES == nack) 
+                               ? GNUNET_MESSAGE_TYPE_DV_SEND_NACK
+                               : GNUNET_MESSAGE_TYPE_DV_SEND_ACK);
   ack_msg.uid = htonl (uid);
   ack_msg.target = *target;
   send_control_to_plugin (&ack_msg.header);
@@ -610,7 +612,8 @@ core_transmit_notify (void *cls, size_t size, void *buf)
     memcpy (&cbuf[off], pending->msg, msize);
     if (0 != pending->uid) 
       send_ack_to_plugin (&pending->ultimate_target,
-                          pending->uid);
+                          pending->uid,
+                          GNUNET_NO);
     GNUNET_free (pending);
     off += msize;
   }
@@ -1321,12 +1324,11 @@ handle_dv_send_message (void *cls, struct GNUNET_SERVER_Client *client,
                                              &msg->target.hashPubKey);
   if (NULL == route)
   {
-    /* got disconnected, send ACK anyway? 
-       FIXME: What we really want is an 'NACK' here... */
+    /* got disconnected */
     GNUNET_STATISTICS_update (stats,
                               "# local messages discarded (no route)",
                               1, GNUNET_NO);
-    send_ack_to_plugin (&msg->target, ntohl (msg->uid));
+    send_ack_to_plugin (&msg->target, ntohl (msg->uid), GNUNET_YES);
     GNUNET_SERVER_receive_done (client, GNUNET_OK);
     return;
   }