From eadb185a411fe68d5bd08dc6526e49046e3bfc86 Mon Sep 17 00:00:00 2001
From: Bart Polot <bart@net.in.tum.de>
Date: Thu, 11 Jul 2013 11:58:09 +0000
Subject: [PATCH] - avoid POLL messing with reliability counter

---
 src/mesh/gnunet-service-mesh.c | 67 +++++++++++++++++++++++++++-------
 1 file changed, 53 insertions(+), 14 deletions(-)

diff --git a/src/mesh/gnunet-service-mesh.c b/src/mesh/gnunet-service-mesh.c
index 6ba811b52..d330fb42a 100644
--- a/src/mesh/gnunet-service-mesh.c
+++ b/src/mesh/gnunet-service-mesh.c
@@ -3181,31 +3181,67 @@ queue_add (void *cls, uint16_t type, size_t size,
 {
   struct MeshPeerQueue *queue;
   struct GNUNET_PeerIdentity id;
-  unsigned int *n;
+  struct MeshFlowControl *fc;
+  uint32_t pid;
+  uint32_t pid_q;
+  int priority;
 
-  n = NULL;
+  fc = NULL;
+  priority = GNUNET_NO;
   if (GNUNET_MESSAGE_TYPE_MESH_UNICAST == type)
   {
-    n = &t->next_fc.queue_n;
+    fc = &t->next_fc;
+    pid = ntohl (((struct GNUNET_MESH_Data *)cls)->pid);
   }
   else if (GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN == type)
   {
-    n = &t->prev_fc.queue_n;
+    fc = &t->prev_fc;
+    pid = ntohl (((struct GNUNET_MESH_Data *)cls)->pid);
   }
-  if (NULL != n)
+  if (NULL != fc)
   {
-    if (*n >= t->queue_max)
+    if (fc->queue_n >= t->queue_max)
     {
-      GNUNET_break(0);
+      GNUNET_break (0);
       GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                   "queue full: %u/%u\n",
-                  *n, t->queue_max);
-      GNUNET_STATISTICS_update(stats,
-                               "# messages dropped (buffer full)",
-                               1, GNUNET_NO);
-      return; /* Drop message */
+                  fc->queue_n, t->queue_max);
+      GNUNET_STATISTICS_update (stats,
+                                "# messages dropped (buffer full)",
+                                1, GNUNET_NO);
+      /* Get the PID of the oldest message in the queue */
+      for (queue = dst->queue_head; queue != NULL; queue = queue->next)
+        if (queue->type == type && queue->tunnel == t)
+        {
+          pid_q = ntohl (((struct GNUNET_MESH_Data *)(queue->cls))->pid);
+          break;
+        }
+      GNUNET_assert (NULL != queue);
+
+      /* If this is an earlier message that that, give it priority:
+       * - drop the newest message in the queue
+       * - instert current one at the end of the queue (first to get out)
+       */
+      if (GNUNET_YES == t->reliable && GMC_is_pid_bigger(pid_q, pid))
+      {
+        for (queue = dst->queue_tail; queue != NULL; queue = queue->prev)
+          if (queue->type == type && queue->tunnel == t)
+          {
+            /* Drop message from queue */
+            GNUNET_CONTAINER_DLL_remove (dst->queue_head,
+                                         dst->queue_tail,
+                                         queue);
+            queue_destroy (queue, GNUNET_YES);
+            fc->queue_n--;
+            t->pending_messages--;
+            priority = GNUNET_YES;
+            break;
+          }
+      }
+      else
+        return; /* Drop this message */
     }
-    (*n)++;
+    fc->queue_n++;
   }
   queue = GNUNET_malloc (sizeof (struct MeshPeerQueue));
   queue->cls = cls;
@@ -3213,7 +3249,10 @@ queue_add (void *cls, uint16_t type, size_t size,
   queue->size = size;
   queue->peer = dst;
   queue->tunnel = t;
-  GNUNET_CONTAINER_DLL_insert_tail (dst->queue_head, dst->queue_tail, queue);
+  if (GNUNET_YES == priority)
+    GNUNET_CONTAINER_DLL_insert (dst->queue_head, dst->queue_tail, queue);
+  else
+    GNUNET_CONTAINER_DLL_insert_tail (dst->queue_head, dst->queue_tail, queue);
   if (NULL == dst->core_transmit)
   {
     GNUNET_PEER_resolve (dst->id, &id);
-- 
2.25.1