Merge branch 'fix_social' of gnunet.org:gnunet into fix_social

26 files changed, 207 insertions, 104 deletions

diff --git a/src/cadet/gnunet-service-cadet_tunnels.c b/src/cadet/gnunet-service-cadet_tunnels.c
index 22e19ef70..fb91a4a6a 100644
--- a/src/cadet/gnunet-service-cadet_tunnels.c
+++ b/src/cadet/gnunet-service-cadet_tunnels.c
@@ -2856,7 +2856,9 @@ handle_plaintext_channel_destroy (void *cls,
  *
  * @param cls the `struct CadetTunnel` that got the message
  * @param msg the message
- * @return #GNUNET_OK (continue to process)
+ * @return #GNUNET_OK on success (always)
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 handle_decrypted (void *cls,
diff --git a/src/conversation/gnunet-helper-audio-playback-gst.c b/src/conversation/gnunet-helper-audio-playback-gst.c
index 264b14e76..002fed6c7 100644
--- a/src/conversation/gnunet-helper-audio-playback-gst.c
+++ b/src/conversation/gnunet-helper-audio-playback-gst.c
@@ -221,6 +221,11 @@ feed_buffer_to_gst (const char *audio, size_t b_len)
 
 /**
  * Message callback
+ *
+ * @param msg message we received.
+ * @return #GNUNET_OK on success,
+ *     #GNUNET_NO to stop further processing due to disconnect (no error)
+ *     #GNUNET_SYSERR to stop further processing due to error
  */
 static int
 stdin_receiver (void *cls,
diff --git a/src/conversation/gnunet-helper-audio-playback.c b/src/conversation/gnunet-helper-audio-playback.c
index 4344e1d41..18f63ad18 100644
--- a/src/conversation/gnunet-helper-audio-playback.c
+++ b/src/conversation/gnunet-helper-audio-playback.c
@@ -546,6 +546,11 @@ ogg_demux_and_decode ()
 
 /**
  * Message callback
+ *
+ * @param msg message we received.
+ * @return #GNUNET_OK on success,
+ *     #GNUNET_NO to stop further processing due to disconnect (no error)
+ *     #GNUNET_SYSERR to stop further processing due to error
  */
 static int
 stdin_receiver (void *cls,
diff --git a/src/conversation/gnunet_gst.c b/src/conversation/gnunet_gst.c
index 52cb2ccbc..828b35077 100644
--- a/src/conversation/gnunet_gst.c
+++ b/src/conversation/gnunet_gst.c
@@ -649,6 +649,11 @@ gnunet_read (GNUNET_gstData * d)
 
 /**
  * Message callback
+ *
+ * @param msg message we received.
+ * @return #GNUNET_OK on success,
+ *     #GNUNET_NO to stop further processing due to disconnect (no error)
+ *     #GNUNET_SYSERR to stop further processing due to error
  */
 static int
 stdin_receiver (void *cls,
diff --git a/src/conversation/microphone.c b/src/conversation/microphone.c
index 7871433a3..11468fc59 100644
--- a/src/conversation/microphone.c
+++ b/src/conversation/microphone.c
@@ -65,7 +65,9 @@ struct Microphone
  *
  * @param cls clsoure with our `struct Microphone`
  * @param msg the message from the helper
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 process_record_messages (void *cls,
diff --git a/src/core/gnunet-service-core.c b/src/core/gnunet-service-core.c
index 625bf9655..214f72904 100644
--- a/src/core/gnunet-service-core.c
+++ b/src/core/gnunet-service-core.c
@@ -426,6 +426,9 @@ struct TokenizerContext
  *
  * @param cls reservation request (`struct TokenizerContext`)
  * @param message the actual message
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 tokenized_cb (void *cls,
diff --git a/src/core/gnunet-service-core_kx.c b/src/core/gnunet-service-core_kx.c
index 8a7cada5c..ae0ae508f 100644
--- a/src/core/gnunet-service-core_kx.c
+++ b/src/core/gnunet-service-core_kx.c
@@ -708,6 +708,9 @@ setup_fresh_ping (struct GSC_KeyExchangeInfo *kx)
  *
  * @param cls the `struct GSC_KeyExchangeInfo`
  * @param m the message
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 deliver_message (void *cls,
diff --git a/src/fs/fs_dirmetascan.c b/src/fs/fs_dirmetascan.c
index 7b9f178fd..8a3e37b49 100644
--- a/src/fs/fs_dirmetascan.c
+++ b/src/fs/fs_dirmetascan.c
@@ -246,6 +246,9 @@ finish_scan (void *cls)
  *
  * @param cls the closure (directory scanner object)
  * @param msg message from the helper process
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 process_helper_msgs (void *cls,
diff --git a/src/include/gnunet_mst_lib.h b/src/include/gnunet_mst_lib.h
index 7a1ca7a55..fe6524eb3 100644
--- a/src/include/gnunet_mst_lib.h
+++ b/src/include/gnunet_mst_lib.h
@@ -61,7 +61,9 @@ struct GNUNET_MessageStreamTokenizer;
  *
  * @param cls closure
  * @param message the actual message
- * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
+ * @return #GNUNET_OK on success,
+ *     #GNUNET_NO to stop further processing due to disconnect (no error)
+ *     #GNUNET_SYSERR to stop further processing due to error
  */
 typedef int
 (*GNUNET_MessageTokenizerCallback) (void *cls,
diff --git a/src/include/gnunet_service_lib.h b/src/include/gnunet_service_lib.h
index aacafe956..dda827c95 100644
--- a/src/include/gnunet_service_lib.h
+++ b/src/include/gnunet_service_lib.h
@@ -366,11 +366,16 @@ GNUNET_SERVICE_client_disable_continue_warning (struct GNUNET_SERVICE_Client *c)
 /**
  * Ask the server to disconnect from the given client.  This is the
  * same as returning #GNUNET_SYSERR within the check procedure when
- * handling a message, wexcept that it allows dropping of a client even
+ * handling a message, except that it allows dropping of a client even
  * when not handling a message from that client.  The `disconnect_cb`
  * will be called on @a c even if the application closes the connection
  * using this function.
  *
+ * This function should be called (outside of util's internal logic)
+ * if (and usually only if) the client has violated the
+ * protocol. Otherwise, we should leave it to the client to disconnect
+ * from the service.
+ *
  * @param c client to disconnect now
  */
 void
diff --git a/src/psyc/psyc_api.c b/src/psyc/psyc_api.c
index c93d8b383..e7790d201 100644
--- a/src/psyc/psyc_api.c
+++ b/src/psyc/psyc_api.c
@@ -931,7 +931,8 @@ slave_reconnect (void *cls)
  * Reconnect after backoff period.
  */
 static void
-slave_disconnected (void *cls, enum GNUNET_MQ_Error error)
+slave_disconnected (void *cls,
+                    enum GNUNET_MQ_Error error)
 {
   struct GNUNET_PSYC_Slave *slv = cls;
   struct GNUNET_PSYC_Channel *chn = &slv->chn;
@@ -950,7 +951,7 @@ slave_disconnected (void *cls, enum GNUNET_MQ_Error error)
     chn->mq = NULL;
   }
   chn->reconnect_task = GNUNET_SCHEDULER_add_delayed (chn->reconnect_delay,
-                                                      slave_reconnect,
+                                                      &slave_reconnect,
                                                       slv);
   chn->reconnect_delay = GNUNET_TIME_STD_BACKOFF (chn->reconnect_delay);
 }
@@ -993,9 +994,19 @@ slave_connect (struct GNUNET_PSYC_Slave *slv)
     GNUNET_MQ_handler_end ()
   };
 
-  chn->mq = GNUNET_CLIENT_connect (chn->cfg, "psyc",
-                                   handlers, slave_disconnected, slv);
-  GNUNET_assert (NULL != chn->mq);
+  chn->mq = GNUNET_CLIENT_connect (chn->cfg,
+                                   "psyc",
+                                   handlers,
+                                   &slave_disconnected,
+                                   slv);
+  if (NULL == chn->mq)
+  {
+    chn->reconnect_task = GNUNET_SCHEDULER_add_delayed (chn->reconnect_delay,
+                                                        &slave_reconnect,
+                                                        slv);
+    chn->reconnect_delay = GNUNET_TIME_STD_BACKOFF (chn->reconnect_delay);
+    return;
+  }
   chn->tmit = GNUNET_PSYC_transmit_create (chn->mq);
 
   GNUNET_MQ_send_copy (chn->mq, chn->connect_env);
diff --git a/src/social/gnunet-service-social.c b/src/social/gnunet-service-social.c
index f9e70a25d..04bbba192 100644
--- a/src/social/gnunet-service-social.c
+++ b/src/social/gnunet-service-social.c
@@ -570,7 +570,6 @@ client_notify_disconnect (void *cls,
 
   if (NULL != c->app_id)
     GNUNET_free (c->app_id);
-
   GNUNET_free (c);
 
   if (NULL == plc)
@@ -586,7 +585,9 @@ client_notify_disconnect (void *cls,
   {
     if (cli->client == client)
     {
-      GNUNET_CONTAINER_DLL_remove (plc->clients_head, plc->clients_tail, cli);
+      GNUNET_CONTAINER_DLL_remove (plc->clients_head,
+                                   plc->clients_tail,
+                                   cli);
       GNUNET_free (cli);
       break;
     }
@@ -608,11 +609,13 @@ client_notify_connect (void *cls,
                        struct GNUNET_SERVICE_Client *client,
                        struct GNUNET_MQ_Handle *mq)
 {
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Client connected: %p\n", client);
+  struct Client *c = GNUNET_new (struct Client);
 
-  struct Client *c = GNUNET_malloc (sizeof (*c));
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Client %p connected with queue %p\n",
+              client,
+              mq);
   c->client = client;
-
   return c;
 }
 
@@ -2204,7 +2207,7 @@ handle_client_app_detach (void *cls,
 }
 
 
-int
+static int
 app_places_entry_remove (void *cls, const struct GNUNET_HashCode *key, void *value)
 {
   struct Place *plc = cls;
@@ -2247,15 +2250,14 @@ handle_client_place_leave (void *cls,
   /* FIXME: disconnect from the network, but keep local connection for history access */
 
   /* Disconnect all clients connected to the place */
-  struct ClientListItem *cli = plc->clients_head, *next;
-  while (NULL != cli)
+
+  for (struct ClientListItem *cli = plc->clients_head;
+       NULL != cli;
+       cli = cli->next)
   {
-    GNUNET_CONTAINER_DLL_remove (plc->clients_head, plc->clients_tail, cli);
     // protocol design failure: should *tell* clients that room is gone!
-    GNUNET_SERVICE_client_drop (cli->client);
-    next = cli->next;
-    GNUNET_free (cli);
-    cli = next;
+    if (client != cli->client)
+      GNUNET_SERVICE_client_drop (cli->client);
   }
 
   if (GNUNET_YES != plc->is_disconnected)
@@ -2268,10 +2270,11 @@ handle_client_place_leave (void *cls,
     else
     {
       cleanup_place (plc);
+      c->place = NULL;
     }
   }
   // FIXME: can't continue+drop above, but should not drop above!
-  // GNUNET_SERVICE_client_continue (client);
+  GNUNET_SERVICE_client_continue (client);
 }
 
 
@@ -2989,7 +2992,6 @@ handle_client_psyc_message (void *cls,
                 "%p Received message with invalid payload size (%u) from client.\n",
                 plc, psize);
     GNUNET_break (0);
-    psyc_transmit_cancel (plc, client);
     GNUNET_SERVICE_client_drop (client);
     return;
   }
@@ -3003,7 +3005,6 @@ handle_client_psyc_message (void *cls,
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "%p Received invalid message part from client.\n", plc);
     GNUNET_break (0);
-    psyc_transmit_cancel (plc, client);
     GNUNET_SERVICE_client_drop (client);
     return;
   }
@@ -3029,7 +3030,6 @@ handle_client_psyc_message (void *cls,
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "%p Received invalid message part from client.\n", plc);
     GNUNET_break (0);
-    psyc_transmit_cancel (plc, client);
     ret = GNUNET_SYSERR;
   }
 
diff --git a/src/social/social_api.c b/src/social/social_api.c
index fc649fcde..1db8e501a 100644
--- a/src/social/social_api.c
+++ b/src/social/social_api.c
@@ -1044,6 +1044,7 @@ static void
 place_cleanup (struct GNUNET_SOCIAL_Place *plc)
 {
   struct GNUNET_HashCode place_pub_hash;
+
   GNUNET_CRYPTO_hash (&plc->pub_key, sizeof (plc->pub_key), &place_pub_hash);
   GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
               "%s place cleanup: %s\n",
@@ -2092,6 +2093,8 @@ leave_done_cont (void *cls)
 {
   struct LeaveContext *lc = cls;
 
+  GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+              "social_api: guest's place_leave message sent!\n");
   GNUNET_SOCIAL_guest_disconnect (lc->gst,
                                   lc->disconnect_cb,
                                   lc->disconnect_cb_cls);
diff --git a/src/social/test_social.c b/src/social/test_social.c
index 8d49e7413..de2299320 100644
--- a/src/social/test_social.c
+++ b/src/social/test_social.c
@@ -180,10 +180,28 @@ host_announce2 ();
 
 
 /**
- * Clean up all resources used.
+ * Terminate the test case (failure).
+ *
+ * @param cls NULL
  */
 static void
-cleanup ()
+end_badly (void *cls)
+{
+  end_badly_task = NULL;
+  GNUNET_SCHEDULER_shutdown ();
+  res = 2;
+  GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+              "Test FAILED.\n");
+}
+
+
+/**
+ * Terminate the test case (failure).
+ *
+ * @param cls NULL
+ */
+static void
+end_shutdown (void *cls)
 {
   if (NULL != id)
   {
@@ -202,7 +220,11 @@ cleanup ()
     GNUNET_PSYC_slicer_destroy (host_slicer);
     host_slicer = NULL;
   }
-
+  if (NULL != end_badly_task)
+  {
+    GNUNET_SCHEDULER_cancel (end_badly_task);
+    end_badly_task = NULL;
+  }
   if (NULL != gst)
   {
     GNUNET_SOCIAL_guest_leave (gst, NULL, NULL, NULL);
@@ -216,21 +238,6 @@ cleanup ()
     hst_plc = NULL;
   }
   GNUNET_SOCIAL_app_disconnect (app, NULL, NULL);
-  GNUNET_SCHEDULER_shutdown ();
-}
-
-
-/**
- * Terminate the test case (failure).
- *
- * @param cls NULL
- */
-static void
-end_badly (void *cls)
-{
-  res = 1;
-  cleanup ();
-  GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Test FAILED.\n");
 }
 
 
@@ -242,8 +249,8 @@ end_badly (void *cls)
 static void
 end_normally (void *cls)
 {
+  GNUNET_SCHEDULER_shutdown ();
   res = 0;
-  cleanup ();
   GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE, "Test PASSED.\n");
 }
 
@@ -372,6 +379,7 @@ host_reconnected (void *cls, int result,
   is_host_reconnected = GNUNET_YES;
   if (GNUNET_YES == is_guest_reconnected)
   {
+    GNUNET_assert (NULL != gst);
     GNUNET_SCHEDULER_add_now (&schedule_guest_leave, NULL);
   }
 }
@@ -390,6 +398,7 @@ guest_reconnected (void *cls, int result,
   is_guest_reconnected = GNUNET_YES;
   if (GNUNET_YES == is_host_reconnected)
   {
+    GNUNET_assert (NULL != gst);
     GNUNET_SCHEDULER_add_now (&schedule_guest_leave, NULL);
   }
 }
@@ -411,11 +420,15 @@ app_recv_host (void *cls,
                enum GNUNET_SOCIAL_AppPlaceState place_state)
 {
   struct GNUNET_HashCode host_pub_hash;
-  GNUNET_CRYPTO_hash (host_pub_key, sizeof (*host_pub_key), &host_pub_hash);
+
+  GNUNET_CRYPTO_hash (host_pub_key,
+                      sizeof (*host_pub_key),
+                      &host_pub_hash);
 
   GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
               "Test #%u: Got app host place notification: %s\n",
-              test, GNUNET_h2s (&host_pub_hash));
+              test,
+              GNUNET_h2s (&host_pub_hash));
 
   if (test == TEST_RECONNECT)
   {
@@ -424,8 +437,11 @@ app_recv_host (void *cls,
       GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
                   "Test #%u: Reconnecting to host place: %s\n",
                   test, GNUNET_h2s (&host_pub_hash));
-      hst = GNUNET_SOCIAL_host_enter_reconnect (hconn, host_slicer, host_reconnected,
-                                                host_answer_door, host_farewell2, NULL);
+      hst = GNUNET_SOCIAL_host_enter_reconnect (hconn, host_slicer,
+                                                &host_reconnected,
+                                                &host_answer_door,
+                                                &host_farewell2,
+                                                NULL);
     }
   }
 }
@@ -439,7 +455,10 @@ app_recv_guest (void *cls,
                 enum GNUNET_SOCIAL_AppPlaceState place_state)
 {
   struct GNUNET_HashCode guest_pub_hash;
-  GNUNET_CRYPTO_hash (guest_pub_key, sizeof (*guest_pub_key), &guest_pub_hash);
+
+  GNUNET_CRYPTO_hash (guest_pub_key,
+                      sizeof (*guest_pub_key),
+                      &guest_pub_hash);
 
   GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
               "Test #%u: Got app guest place notification: %s\n",
@@ -447,13 +466,19 @@ app_recv_guest (void *cls,
 
   if (test == TEST_RECONNECT)
   {
-    if (0 == memcmp (&place_pub_key, guest_pub_key, sizeof (*guest_pub_key)))
+    if (0 == memcmp (&place_pub_key,
+                     guest_pub_key,
+                     sizeof (*guest_pub_key)))
     {
       GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
                   "Test #%u: Reconnecting to guest place: %s\n",
                   test, GNUNET_h2s (&guest_pub_hash));
-      gst = GNUNET_SOCIAL_guest_enter_reconnect (gconn, GNUNET_PSYC_SLAVE_JOIN_NONE,
-                                                 guest_slicer, guest_reconnected, NULL);
+      gst = GNUNET_SOCIAL_guest_enter_reconnect (gconn,
+                                                 GNUNET_PSYC_SLAVE_JOIN_NONE,
+                                                 guest_slicer,
+                                                 &guest_reconnected,
+                                                 NULL);
+      GNUNET_assert (NULL != gst);
     }
   }
 }
@@ -527,10 +552,10 @@ schedule_reconnect (void *cls)
 
   GNUNET_SOCIAL_app_disconnect (app, NULL, NULL);
   app = GNUNET_SOCIAL_app_connect (cfg, app_id,
-                                   app_recv_ego,
-                                   app_recv_host,
-                                   app_recv_guest,
-                                   app_connected,
+                                   &app_recv_ego,
+                                   &app_recv_host,
+                                   &app_recv_guest,
+                                   &app_connected,
                                    NULL);
 }
 
@@ -1387,9 +1412,11 @@ run (void *cls,
 #endif
 {
   cfg = c;
+  res = 1;
   end_badly_task = GNUNET_SCHEDULER_add_delayed (TIMEOUT,
                                                  &end_badly, NULL);
-
+  GNUNET_SCHEDULER_add_shutdown (&end_shutdown,
+                                 NULL);
   GNUNET_CRYPTO_get_peer_identity (cfg, &this_peer);
 
   id = GNUNET_IDENTITY_connect (cfg, &identity_ego_cb, NULL);
diff --git a/src/social/test_social.conf b/src/social/test_social.conf
index 52ed20c6b..a11144b60 100644
--- a/src/social/test_social.conf
+++ b/src/social/test_social.conf
@@ -3,3 +3,6 @@
 [social]
 AUTOSTART = YES
 FORCESTART = YES
+
+[transport]
+PLUGINS = udp
diff --git a/src/statistics/gnunet-service-statistics.c b/src/statistics/gnunet-service-statistics.c
index 0cb136b99..87e966a01 100644
--- a/src/statistics/gnunet-service-statistics.c
+++ b/src/statistics/gnunet-service-statistics.c
@@ -998,7 +998,9 @@ client_disconnect_cb (void *cls,
  *
  * @param cls NULL
  * @param message the message found on disk
- * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 inject_message (void *cls,
diff --git a/src/testbed/gnunet-helper-testbed.c b/src/testbed/gnunet-helper-testbed.c
index 392f257dd..9601e7567 100644
--- a/src/testbed/gnunet-helper-testbed.c
+++ b/src/testbed/gnunet-helper-testbed.c
@@ -292,8 +292,9 @@ child_death_task (void *cls)
  *
  * @param cls identification of the client
  * @param message the actual message
- *
- * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 tokenizer_cb (void *cls,
@@ -359,7 +360,7 @@ tokenizer_cb (void *cls,
   cfg = GNUNET_CONFIGURATION_create ();
   if (GNUNET_OK !=
       GNUNET_CONFIGURATION_deserialize (cfg,
-                                        config, 
+                                        config,
                                         ul_config_size,
                                         NULL))
   {
diff --git a/src/transport/gnunet-helper-transport-wlan-dummy.c b/src/transport/gnunet-helper-transport-wlan-dummy.c
index 63ed9c4b7..f02d8bdd7 100644
--- a/src/transport/gnunet-helper-transport-wlan-dummy.c
+++ b/src/transport/gnunet-helper-transport-wlan-dummy.c
@@ -121,6 +121,9 @@ send_mac_to_plugin (char *buffer, struct GNUNET_TRANSPORT_WLAN_MacAddress *mac)
  *
  * @param cls the 'struct SendBuffer' to copy the converted message to
  * @param hdr inbound message from the FIFO
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 stdin_send (void *cls,
@@ -167,6 +170,9 @@ stdin_send (void *cls,
  *
  * @param cls the 'struct SendBuffer' to copy to
  * @param hdr the message we received to copy to the buffer
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 file_in_send (void *cls,
diff --git a/src/transport/plugin_transport_http_server.c b/src/transport/plugin_transport_http_server.c
index d9fade44f..6a9c1b0ba 100644
--- a/src/transport/plugin_transport_http_server.c
+++ b/src/transport/plugin_transport_http_server.c
@@ -1651,7 +1651,7 @@ server_send_callback (void *cls,
  *
  * @param cls current session as closure
  * @param message the message to be forwarded to transport service
- * @return #GNUNET_OK
+ * @return #GNUNET_OK (all OK)
  */
 static int
 server_receive_mst_cb (void *cls,
diff --git a/src/transport/tcp_server_legacy.c b/src/transport/tcp_server_legacy.c
index 6b4daa525..d0ce790fc 100644
--- a/src/transport/tcp_server_legacy.c
+++ b/src/transport/tcp_server_legacy.c
@@ -1477,23 +1477,6 @@ GNUNET_SERVER_connect_notify_cancel (struct GNUNET_SERVER_Handle *server,
 
 
 /**
- * Destroy the connection that is passed in via @a cls.  Used
- * as calling #GNUNET_CONNECTION_destroy from within a function
- * that was itself called from within process_notify() of
- * 'connection.c' is not allowed (see #2329).
- *
- * @param cls connection to destroy
- */
-static void
-destroy_connection (void *cls)
-{
-  struct GNUNET_CONNECTION_Handle *connection = cls;
-
-  GNUNET_CONNECTION_destroy (connection);
-}
-
-
-/**
  * Ask the server to disconnect from the given client.
  * This is the same as returning #GNUNET_SYSERR from a message
  * handler, except that it allows dropping of a client even
@@ -1565,8 +1548,7 @@ GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client)
     GNUNET_CONNECTION_persist_ (client->connection);
   if (NULL != client->th.cth)
     GNUNET_SERVER_notify_transmit_ready_cancel (&client->th);
-  (void) GNUNET_SCHEDULER_add_now (&destroy_connection,
-                                   client->connection);
+  GNUNET_CONNECTION_destroy (client->connection);
   /* need to cancel again, as it might have been re-added
      in the meantime (i.e. during callbacks) */
   if (NULL != client->warn_task)
diff --git a/src/util/client.c b/src/util/client.c
index cf75dffbc..a5eae2a75 100644
--- a/src/util/client.c
+++ b/src/util/client.c
@@ -308,7 +308,9 @@ transmit_ready (void *cls)
  *
  * @param cls the `struct ClientState`
  * @param msg message we received.
- * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
+ * @return #GNUNET_OK on success,
+ *     #GNUNET_NO to stop further processing due to disconnect (no error)
+ *     #GNUNET_SYSERR to stop further processing due to error
  */
 static int
 recv_message (void *cls,
@@ -317,7 +319,7 @@ recv_message (void *cls,
   struct ClientState *cstate = cls;
 
   if (GNUNET_YES == cstate->in_destroy)
-    return GNUNET_SYSERR;
+    return GNUNET_NO;
   LOG (GNUNET_ERROR_TYPE_DEBUG,
        "Received message of type %u and size %u from %s\n",
        ntohs (msg->type),
@@ -326,7 +328,7 @@ recv_message (void *cls,
   GNUNET_MQ_inject_message (cstate->mq,
                             msg);
   if (GNUNET_YES == cstate->in_destroy)
-    return GNUNET_SYSERR;
+    return GNUNET_NO;
   return GNUNET_OK;
 }
 
diff --git a/src/util/mq.c b/src/util/mq.c
index c7ed5330e..6ad6b82eb 100644
--- a/src/util/mq.c
+++ b/src/util/mq.c
@@ -221,8 +221,10 @@ GNUNET_MQ_inject_message (struct GNUNET_MQ_Handle *mq,
   uint16_t mtype = ntohs (mh->type);
 
   LOG (GNUNET_ERROR_TYPE_DEBUG,
-       "Received message of type %u and size %u\n",
-       mtype, msize);
+       "Queue %p received message of type %u and size %u\n",
+       mq,
+       mtype,
+       msize);
 
   if (NULL == mq->handlers)
     goto done;
@@ -359,7 +361,8 @@ GNUNET_MQ_send (struct GNUNET_MQ_Handle *mq,
   mq->current_envelope = ev;
 
   GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-              "mq: sending message of type %u, queue empty\n", ntohs(ev->mh->type));
+              "mq: sending message of type %u, queue empty\n",
+              ntohs(ev->mh->type));
 
   mq->send_impl (mq,
                  ev->mh,
@@ -848,6 +851,9 @@ GNUNET_MQ_destroy (struct GNUNET_MQ_Handle *mq)
                                  ev);
     GNUNET_assert (0 < mq->queue_length);
     mq->queue_length--;
+    GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                "MQ destroy drops message of type %u\n",
+                ntohs (ev->mh->type));
     GNUNET_MQ_discard (ev);
   }
   if (NULL != mq->current_envelope)
@@ -855,6 +861,9 @@ GNUNET_MQ_destroy (struct GNUNET_MQ_Handle *mq)
     /* we can only discard envelopes that
      * are not queued! */
     mq->current_envelope->parent_queue = NULL;
+    GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                "MQ destroy drops message of type %u\n",
+                ntohs (mq->current_envelope->mh->type));
     GNUNET_MQ_discard (mq->current_envelope);
     mq->current_envelope = NULL;
     GNUNET_assert (0 < mq->queue_length);
diff --git a/src/util/mst.c b/src/util/mst.c
index 0d90c5d10..5e472965f 100644
--- a/src/util/mst.c
+++ b/src/util/mst.c
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet.
-     Copyright (C) 2010, 2016 GNUnet e.V.
+     Copyright (C) 2010, 2016, 2017 GNUnet e.V.
 
      GNUnet is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published
@@ -126,6 +126,7 @@ GNUNET_MST_from_buffer (struct GNUNET_MessageStreamTokenizer *mst,
   int need_align;
   unsigned long offset;
   int ret;
+  int cbret;
 
   GNUNET_assert (mst->off <= mst->pos);
   GNUNET_assert (mst->pos <= mst->curr_buf);
@@ -229,9 +230,17 @@ do_align:
     if (one_shot == GNUNET_YES)
       one_shot = GNUNET_SYSERR;
     mst->off += want;
-  if (GNUNET_SYSERR == mst->cb (mst->cb_cls,
-                                hdr))
+    if (GNUNET_OK !=
+        (cbret = mst->cb (mst->cb_cls,
+                           hdr)))
+    {
+      if (GNUNET_SYSERR == cbret)
+        GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                    "Failure processing message of type %u and size %u\n",
+                    ntohs (hdr->type),
+                    ntohs (hdr->size));
       return GNUNET_SYSERR;
+    }
     if (mst->off == mst->pos)
     {
       /* reset to beginning of buffer, it's free right now! */
@@ -271,9 +280,17 @@ do_align:
       }
       if (one_shot == GNUNET_YES)
         one_shot = GNUNET_SYSERR;
-      if (GNUNET_SYSERR == mst->cb (mst->cb_cls,
-                                    hdr))
+      if (GNUNET_OK !=
+          (cbret = mst->cb (mst->cb_cls,
+                            hdr)))
+      {
+        if (GNUNET_SYSERR == cbret)
+          GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                      "Failure processing message of type %u and size %u\n",
+                      ntohs (hdr->type),
+                      ntohs (hdr->size));
         return GNUNET_SYSERR;
+      }
       buf += want;
       size -= want;
     }
diff --git a/src/util/scheduler.c b/src/util/scheduler.c
index a7b1d8e2a..b07c51811 100644
--- a/src/util/scheduler.c
+++ b/src/util/scheduler.c
@@ -73,7 +73,7 @@
  * Argument to be passed from the driver to
  * #GNUNET_SCHEDULER_run_from_driver().  Contains the
  * scheduler's internal state.
- */ 
+ */
 struct GNUNET_SCHEDULER_Handle
 {
   /**
@@ -94,7 +94,7 @@ struct GNUNET_SCHEDULER_Handle
    * Driver we used for the event loop.
    */
   const struct GNUNET_SCHEDULER_Driver *driver;
-  
+
 };
 
 
@@ -127,7 +127,7 @@ struct GNUNET_SCHEDULER_Task
    * Handle to the scheduler's state.
    */
   const struct GNUNET_SCHEDULER_Handle *sh;
-  
+
   /**
    * Set of file descriptors this task is waiting
    * for for reading.  Once ready, this is updated
@@ -172,7 +172,7 @@ struct GNUNET_SCHEDULER_Task
    * Size of the @e fds array.
    */
   unsigned int fds_len;
-  
+
   /**
    * Why is the task ready?  Set after task is added to ready queue.
    * Initially set to zero.  All reasons that have already been
@@ -589,9 +589,7 @@ static void
 dump_backtrace (struct GNUNET_SCHEDULER_Task *t)
 {
 #if EXECINFO
-  unsigned int i;
-
-  for (i = 0; i < t->num_backtrace_strings; i++)
+  for (unsigned int i = 0; i < t->num_backtrace_strings; i++)
     LOG (GNUNET_ERROR_TYPE_DEBUG,
          "Task %p trace %u: %s\n",
          t,
@@ -1849,7 +1847,7 @@ GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task,
  *
  * @param sh scheduler handle that was given to the `loop`
  * @return #GNUNET_OK if there are more tasks that are ready,
- *          and thus we would like to run more (yield to avoid 
+ *          and thus we would like to run more (yield to avoid
  *          blocking other activities for too long)
  *         #GNUNET_NO if we are done running tasks (yield to block)
  *         #GNUNET_SYSERR on error
@@ -1876,11 +1874,11 @@ GNUNET_SCHEDULER_run_from_driver (struct GNUNET_SCHEDULER_Handle *sh)
       pending_timeout_last = NULL;
     queue_ready_task (pos);
   }
-  
+
   if (0 == ready_count)
     return GNUNET_NO;
 
-  /* find out which task priority level we are going to 
+  /* find out which task priority level we are going to
      process this time */
   max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
   GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
diff --git a/src/util/service.c b/src/util/service.c
index 10dc93faf..782adf5c5 100644
--- a/src/util/service.c
+++ b/src/util/service.c
@@ -2402,7 +2402,7 @@ resume_client_receive (void *cls)
                          GNUNET_YES);
   if (GNUNET_SYSERR == ret)
   {
-    if (NULL != c->drop_task)
+    if (NULL == c->drop_task)
       GNUNET_SERVICE_client_drop (c);
     return;
   }
@@ -2514,6 +2514,10 @@ GNUNET_SERVICE_client_drop (struct GNUNET_SERVICE_Client *c)
 {
   struct GNUNET_SERVICE_Handle *sh = c->sh;
 
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Client dropped: %p (MQ: %p)\n",
+              c,
+              c->mq);
   if (NULL != c->drop_task)
   {
     /* asked to drop twice! */
diff --git a/src/vpn/gnunet-service-vpn.c b/src/vpn/gnunet-service-vpn.c
index d9daaa7e2..bdc638176 100644
--- a/src/vpn/gnunet-service-vpn.c
+++ b/src/vpn/gnunet-service-vpn.c
@@ -2218,6 +2218,9 @@ route_packet (struct DestinationEntry *destination,
  *
  * @param cls closure, NULL
  * @param message message we got from the client (VPN channel interface)
+ * @return #GNUNET_OK on success,
+ *    #GNUNET_NO to stop further processing (no error)
+ *    #GNUNET_SYSERR to stop further processing with error
  */
 static int
 message_token (void *cls,