doxygen
[oweals/gnunet.git] / src / peerinfo / peerinfo_api.c
index a0cb5c5c4a94323aba029ffcdb1d79393d0e6006..faa56e908b54e43b03acde434c13bbb6522210e5 100644 (file)
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet.
-     (C) 2001, 2002, 2004, 2005, 2007, 2009, 2010 Christian Grothoff (and other contributing authors)
+     (C) 2001, 2002, 2004, 2005, 2007, 2009, 2010, 2012 Christian Grothoff (and other contributing authors)
 
      GNUnet is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published
 #include "gnunet_time_lib.h"
 #include "peerinfo.h"
 
-/**
- * Function to call after transmission has succeeded.
- * 
- * @param cls closure
- * @param success GNUNET_OK if transmission worked, GNUNET_SYSERR on error
- */
-typedef void (*TransmissionContinuation)(void *cls,
-                                        int success);
+#define LOG(kind,...) GNUNET_log_from (kind, "peerinfo-api",__VA_ARGS__)
 
 
 /**
- * Entry in the transmission queue to PEERINFO service.
+ * Entry in the transmission queue to PEERINFO service.  We use
+ * the same structure for queueing 'iteration' requests and
+ * actual 'add' messages.
  */
-struct TransmissionQueueEntry
+struct GNUNET_PEERINFO_AddContext
 {
   /**
    * This is a linked list.
    */
-  struct TransmissionQueueEntry *next;
-  
+  struct GNUNET_PEERINFO_AddContext *next;
+
   /**
    * This is a linked list.
    */
-  struct TransmissionQueueEntry *prev;
+  struct GNUNET_PEERINFO_AddContext *prev;
 
   /**
-   * Function to call after request has been transmitted, or NULL (in which
-   * case we must consider sending the next entry immediately).
+   * Handle to the PEERINFO service.
    */
-  TransmissionContinuation cont;
-  
+  struct GNUNET_PEERINFO_Handle *h;
+
+  /**
+   * Function to call after request has been transmitted, or NULL.
+   */
+  GNUNET_PEERINFO_Continuation cont;
+
   /**
    * Closure for 'cont'.
    */
   void *cont_cls;
 
+  /**
+   * Number of bytes of the request message (follows after this struct).
+   */
+  size_t size;
+
+};
+
+
+/**
+ * Context for an iteration request.
+ */
+struct GNUNET_PEERINFO_IteratorContext
+{
+
+  /**
+   * Kept in a DLL.
+   */
+  struct GNUNET_PEERINFO_IteratorContext *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct GNUNET_PEERINFO_IteratorContext *prev;
+
+  /**
+   * Handle to the PEERINFO service.
+   */
+  struct GNUNET_PEERINFO_Handle *h;
+
+  /**
+   * Function to call with the results.
+   */
+  GNUNET_PEERINFO_Processor callback;
+
+  /**
+   * Closure for 'callback'.
+   */
+  void *callback_cls;
+
+  /**
+   * Our entry in the transmission queue.
+   */
+  struct GNUNET_PEERINFO_AddContext *ac;
+
+  /**
+   * Task responsible for timeout.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+
   /**
    * Timeout for the operation.
    */
   struct GNUNET_TIME_Absolute timeout;
 
   /**
-   * Number of bytes of the request message (follows after this struct).
+   * Peer we are interested in (only valid if iteration was restricted to one peer).
    */
-  size_t size;
+  struct GNUNET_PeerIdentity peer;
+
+  /**
+   * Is 'peer' set?
+   */
+  int have_peer;
+
+  /**
+   * Set to GNUNET_YES if we are currently receiving replies from the
+   * service.
+   */
+  int request_transmitted;
 
 };
 
@@ -98,12 +157,12 @@ struct GNUNET_PEERINFO_Handle
   /**
    * Head of transmission queue.
    */
-  struct TransmissionQueueEntry *tq_head;
+  struct GNUNET_PEERINFO_AddContext *ac_head;
 
   /**
    * Tail of transmission queue.
    */
-  struct TransmissionQueueEntry *tq_tail;
+  struct GNUNET_PEERINFO_AddContext *ac_tail;
 
   /**
    * Handle for the current transmission request, or NULL if none is pending.
@@ -111,8 +170,22 @@ struct GNUNET_PEERINFO_Handle
   struct GNUNET_CLIENT_TransmitHandle *th;
 
   /**
-   * Set to GNUNET_YES if we are currently receiving replies from the
-   * service.
+   * Head of iterator DLL.
+   */
+  struct GNUNET_PEERINFO_IteratorContext *ic_head;
+
+  /**
+   * Tail of iterator DLL.
+   */
+  struct GNUNET_PEERINFO_IteratorContext *ic_tail;
+
+  /**
+   * ID for a reconnect task.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier r_task;
+
+  /**
+   * Are we now receiving?
    */
   int in_receive;
 
@@ -129,16 +202,12 @@ struct GNUNET_PEERINFO_Handle
 struct GNUNET_PEERINFO_Handle *
 GNUNET_PEERINFO_connect (const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
-  struct GNUNET_CLIENT_Connection *client;
-  struct GNUNET_PEERINFO_Handle *ret;
-
-  client = GNUNET_CLIENT_connect ("peerinfo", cfg);
-  if (client == NULL)
-    return NULL;
-  ret = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_Handle));
-  ret->client = client;
-  ret->cfg = cfg;
-  return ret;
+  struct GNUNET_PEERINFO_Handle *h;
+
+  h = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_Handle));
+  h->client = GNUNET_CLIENT_connect ("peerinfo", cfg);
+  h->cfg = cfg;
+  return h;
 }
 
 
@@ -154,23 +223,37 @@ GNUNET_PEERINFO_connect (const struct GNUNET_CONFIGURATION_Handle *cfg)
 void
 GNUNET_PEERINFO_disconnect (struct GNUNET_PEERINFO_Handle *h)
 {
-  struct TransmissionQueueEntry *tqe;
-
-  while (NULL != (tqe = h->tq_head))
-    {     
-      GNUNET_CONTAINER_DLL_remove (h->tq_head,
-                                  h->tq_tail,
-                                  tqe);
-      if (tqe->cont != NULL)
-       tqe->cont (tqe->cont_cls, GNUNET_SYSERR);
-      GNUNET_free (tqe);
-    }
-  if (h->th != NULL)
-    {
-      GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
-      h->th = NULL;
-    }
-  GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
+  struct GNUNET_PEERINFO_AddContext *ac;
+  struct GNUNET_PEERINFO_IteratorContext *ic;
+
+  while (NULL != (ic = h->ic_head))
+  {
+    GNUNET_break (GNUNET_YES == ic->request_transmitted);
+    ic->request_transmitted = GNUNET_NO;
+    GNUNET_PEERINFO_iterate_cancel (ic);
+  }
+  while (NULL != (ac = h->ac_head))
+  {
+    GNUNET_CONTAINER_DLL_remove (h->ac_head, h->ac_tail, ac);
+    if (NULL != ac->cont)
+      ac->cont (ac->cont_cls, _("aborted due to explicit disconnect request"));
+    GNUNET_free (ac);
+  }
+  if (NULL != h->th)
+  {
+    GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
+    h->th = NULL;
+  }
+  if (NULL != h->client)
+  {
+    GNUNET_CLIENT_disconnect (h->client);
+    h->client = NULL;
+  }
+  if (GNUNET_SCHEDULER_NO_TASK != h->r_task)
+  {
+    GNUNET_SCHEDULER_cancel (h->r_task);
+    h->r_task = GNUNET_SCHEDULER_NO_TASK;
+  }
   GNUNET_free (h);
 }
 
@@ -185,6 +268,31 @@ static void
 trigger_transmit (struct GNUNET_PEERINFO_Handle *h);
 
 
+/**
+ * Close the existing connection to PEERINFO and reconnect.
+ *
+ * @param h handle to the service
+ */
+static void
+reconnect (struct GNUNET_PEERINFO_Handle *h);
+
+
+/**
+ * Task scheduled to re-try connecting to the peerinfo service.
+ *
+ * @param cls the 'struct GNUNET_PEERINFO_Handle'
+ * @param tc scheduler context
+ */
+static void
+reconnect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_PEERINFO_Handle *h = cls;
+
+  h->r_task = GNUNET_SCHEDULER_NO_TASK;
+  reconnect (h);
+}
+
+
 /**
  * Close the existing connection to PEERINFO and reconnect.
  *
@@ -193,10 +301,31 @@ trigger_transmit (struct GNUNET_PEERINFO_Handle *h);
 static void
 reconnect (struct GNUNET_PEERINFO_Handle *h)
 {
-  GNUNET_CLIENT_disconnect (h->client, GNUNET_SYSERR);
-  h->th = NULL;
+  if (GNUNET_SCHEDULER_NO_TASK != h->r_task)
+  {
+    GNUNET_SCHEDULER_cancel (h->r_task);
+    h->r_task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  if (NULL != h->th)
+  {
+    GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
+    h->th = NULL;
+  }
+  if (NULL != h->client)
+  {
+    GNUNET_CLIENT_disconnect (h->client);
+    h->client = NULL;
+  }
+  h->in_receive = GNUNET_NO;
   h->client = GNUNET_CLIENT_connect ("peerinfo", h->cfg);
-  GNUNET_assert (h->client != NULL);
+  if (NULL == h->client)
+  {
+    h->r_task =
+        GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, &reconnect_task,
+                                      h);
+    return;
+  }
+  trigger_transmit (h);
 }
 
 
@@ -213,50 +342,39 @@ static size_t
 do_transmit (void *cls, size_t size, void *buf)
 {
   struct GNUNET_PEERINFO_Handle *h = cls;
-  struct TransmissionQueueEntry *tqe = h->tq_head;
+  struct GNUNET_PEERINFO_AddContext *ac = h->ac_head;
   size_t ret;
 
   h->th = NULL;
-  if (buf == NULL)
-    {
-      GNUNET_log (GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK,
-                  _("Failed to transmit message to `%s' service.\n"),
-                 "PEERINFO");
-      if (tqe != NULL)
-       GNUNET_CONTAINER_DLL_remove (h->tq_head,
-                                    h->tq_tail,
-                                    tqe);
-      reconnect (h);
-      trigger_transmit (h);
-      if (tqe != NULL)
-       {
-         if (tqe->cont != NULL)
-           tqe->cont (tqe->cont_cls, GNUNET_SYSERR);
-         GNUNET_free (tqe);
-       }
-      return 0;
-    }
-  /* If it can be NULL above, it can be NULL here to... */
-  if (tqe == NULL)
+  if (NULL == ac)
+    return 0; /* request was cancelled in the meantime */
+  if (NULL == buf)
+  {
+    /* peerinfo service died */
+    LOG (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
+         "Failed to transmit message to `%s' service.\n", "PEERINFO");
+    GNUNET_CONTAINER_DLL_remove (h->ac_head, h->ac_tail, ac);
+    reconnect (h);
+    if (NULL != ac->cont)
+      ac->cont (ac->cont_cls, _("failed to transmit request (service down?)"));
+    GNUNET_free (ac);
     return 0;
-
-  ret = tqe->size;
-  GNUNET_assert (size >= ret);
-  memcpy (buf, &tqe[1], ret);
-#if DEBUG_PEERINFO
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Transmitting request of size %u to `%s' service.\n",
-             ret, 
-             "PEERINFO");
-#endif
-   GNUNET_CONTAINER_DLL_remove (h->tq_head,
-                              h->tq_tail,
-                              tqe);
-  if (tqe->cont != NULL)
-    tqe->cont (tqe->cont_cls, GNUNET_OK);
-  else
+  }
+  ret = ac->size;
+  if (size < ret)
+  {
+    /* change in head of queue (i.e. cancel + add), try again */
     trigger_transmit (h);
-  GNUNET_free (tqe);
+    return 0;
+  }
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Transmitting request of size %u to `%s' service.\n", ret, "PEERINFO");
+  memcpy (buf, &ac[1], ret);
+  GNUNET_CONTAINER_DLL_remove (h->ac_head, h->ac_tail, ac);
+  trigger_transmit (h);
+  if (NULL != ac->cont)
+    ac->cont (ac->cont_cls, NULL);
+  GNUNET_free (ac);
   return ret;
 }
 
@@ -270,24 +388,28 @@ do_transmit (void *cls, size_t size, void *buf)
 static void
 trigger_transmit (struct GNUNET_PEERINFO_Handle *h)
 {
-  struct TransmissionQueueEntry *tqe;
-
-  if (NULL == (tqe = h->tq_head))
-    return NULL;
-  if (h->th != NULL)
-    return NULL;
-  if (h->in_receive == GNUNET_YES)
-    return NULL;
-  h->th = GNUNET_CLIENT_notify_transmit_ready (h->client,
-                                              tqe->size,
-                                              GNUNET_TIME_absolute_get_remaining (tqe->timeout),
-                                              GNUNET_YES,
-                                              &do_transmit, h);  
+  struct GNUNET_PEERINFO_AddContext *ac;
+
+  if (NULL == (ac = h->ac_head))
+    return; /* no requests queued */
+  if (NULL != h->th)
+    return; /* request already pending */
+  if (NULL == h->client)
+  {
+    /* disconnected, try to reconnect */
+    reconnect (h);
+    return;
+  }
+  h->th =
+    GNUNET_CLIENT_notify_transmit_ready (h->client, ac->size,
+                                        GNUNET_TIME_UNIT_FOREVER_REL,
+                                        GNUNET_YES,
+                                        &do_transmit, h);
 }
 
 
 /**
- * Add a host to the persistent list.  This method operates in 
+ * Add a host to the persistent list.  This method operates in
  * semi-reliable mode: if the transmission is not completed by
  * the time 'GNUNET_PEERINFO_disconnect' is called, it will be
  * aborted.  Furthermore, if a second HELLO is added for the
@@ -296,80 +418,61 @@ trigger_transmit (struct GNUNET_PEERINFO_Handle *h)
  *
  * @param h handle to the peerinfo service
  * @param hello the verified (!) HELLO message
+ * @param cont continuation to call when done, NULL is allowed
+ * @param cont_cls closure for 'cont'
+ * @return handle to cancel add operation; all pending
+ *         'add' operations will be cancelled automatically
+ *        on disconnect, so it is not necessary to keep this
+ *        handle (unless 'cont' is NULL and at some point
+ *        calling 'cont' must be prevented)
  */
-void
+struct GNUNET_PEERINFO_AddContext *
 GNUNET_PEERINFO_add_peer (struct GNUNET_PEERINFO_Handle *h,
-                         const struct GNUNET_HELLO_Message *hello)
+                          const struct GNUNET_HELLO_Message *hello,
+                         GNUNET_PEERINFO_Continuation cont,
+                         void *cont_cls)
 {
   uint16_t hs = GNUNET_HELLO_size (hello);
-  struct TransmissionQueueEntry *tqe;
-  
-#if DEBUG_PEERINFO
+  struct GNUNET_PEERINFO_AddContext *ac;
   struct GNUNET_PeerIdentity peer;
+
   GNUNET_assert (GNUNET_OK == GNUNET_HELLO_get_id (hello, &peer));
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Adding peer `%s' to PEERINFO database (%u bytes of `%s')\n",
-             GNUNET_i2s(&peer),
-             hs,
-             "HELLO");
-#endif
-  tqe = GNUNET_malloc (sizeof (struct TransmissionQueueEntry) + hs);
-  tqe->size = hs;
-  tqe->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
-  memcpy (&tqe[1], hello, hs);
-  GNUNET_CONTAINER_DLL_insert_after (h->tq_head,
-                                    h->tq_tail,
-                                    h->tq_tail,
-                                    tqe);
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Adding peer `%s' to PEERINFO database (%u bytes of `%s')\n",
+       GNUNET_i2s (&peer), hs, "HELLO");
+  ac = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_AddContext) + hs);
+  ac->h = h;
+  ac->size = hs;
+  ac->cont = cont;
+  ac->cont_cls = cont_cls;
+  memcpy (&ac[1], hello, hs);
+  GNUNET_CONTAINER_DLL_insert_tail (h->ac_head, h->ac_tail, ac);
   trigger_transmit (h);
+  return ac;
 }
 
 
 /**
- * Context for an iteration request.
+ * Cancel pending 'add' operation.  Must only be called before
+ * either 'cont' or 'GNUNET_PEERINFO_disconnect' are invoked.
+ *
+ * @param ac handle for the add operation to cancel
  */
-struct GNUNET_PEERINFO_IteratorContext
+void 
+GNUNET_PEERINFO_add_peer_cancel (struct GNUNET_PEERINFO_AddContext *ac)
 {
-  /**
-   * Handle to the PEERINFO service.
-   */
-  struct GNUNET_PEERINFO_Handle *h;
-
-  /**
-   * Function to call with the results.
-   */
-  GNUNET_PEERINFO_Processor callback;
-
-  /**
-   * Closure for 'callback'.
-   */
-  void *callback_cls;
-
-  /**
-   * Our entry in the transmission queue.
-   */
-  struct TransmissionQueueEntry *tqe;
-
-  /**
-   * Task responsible for timeout.
-   */
-  GNUNET_SCHEDULER_TaskIdentifier timeout_task;
-
-  /**
-   * Timeout for the operation.
-   */
-  struct GNUNET_TIME_Absolute timeout;
+  struct GNUNET_PEERINFO_Handle *h = ac->h;
 
-  /**
-   * Are we now receiving?
-   */
-  int in_receive;
-};
+  GNUNET_CONTAINER_DLL_remove (h->ac_head, h->ac_tail, ac);
+  GNUNET_free (ac);
+}
 
 
 /**
- * Type of a function to call when we receive a message
- * from the service.
+ * Type of a function to call when we receive a message from the
+ * service.  Call the iterator with the result and (if applicable)
+ * continue to receive more messages or trigger processing the next
+ * event (if applicable).
  *
  * @param cls closure
  * @param msg message received, NULL on timeout or fatal error
@@ -377,89 +480,144 @@ struct GNUNET_PEERINFO_IteratorContext
 static void
 peerinfo_handler (void *cls, const struct GNUNET_MessageHeader *msg)
 {
-  struct GNUNET_PEERINFO_IteratorContext *ic = cls;
+  struct GNUNET_PEERINFO_Handle *h = cls;
+  struct GNUNET_PEERINFO_IteratorContext *ic = h->ic_head;
   const struct InfoMessage *im;
   const struct GNUNET_HELLO_Message *hello;
+  GNUNET_PEERINFO_Processor cb;
+  struct GNUNET_PeerIdentity id;
+  void *cb_cls;
   uint16_t ms;
 
-  ic->h->in_receive = GNUNET_NO;
-  if (msg == NULL)
+  h->in_receive = GNUNET_NO;
+  if (NULL == msg)
+  {
+    /* peerinfo service died, signal error */
+    if (NULL != ic)
     {
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  _("Failed to receive response from `%s' service.\n"),
-                  "PEERINFO");
-      reconnect (ic->h);
-      trigger_transmit (ic->h);
-      if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK)
-       GNUNET_SCHEDULER_cancel (ic->timeout_task);
-      if (ic->callback != NULL)
-       ic->callback (ic->callback_cls, NULL, NULL);
-      GNUNET_free (ic);
-      return;
+      cb = ic->callback;
+      cb_cls = ic->callback_cls;
+      GNUNET_PEERINFO_iterate_cancel (ic);
     }
-  if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_PEERINFO_INFO_END)
+    else
     {
-#if DEBUG_PEERINFO
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                 "Received end of list of peers from `%s' service\n",
-                 "PEERINFO");
-#endif
-      trigger_transmit (ic->h);
-      if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK)
-       GNUNET_SCHEDULER_cancel (ic->timeout_task);
-      if (ic->callback != NULL)
-       ic->callback (ic->callback_cls, NULL, NULL);
-      GNUNET_free (ic);
-      return;
+      cb = NULL;
     }
+    reconnect (h);
+    if (NULL != cb)
+      cb (cb_cls, NULL, NULL,
+         _("Failed to receive response from `PEERINFO' service."));
+    return;
+  }
+  if (NULL == ic)
+  {
+    /* didn't expect a response, reconnect */
+    reconnect (h);
+    return;
+  }
+  ic->request_transmitted = GNUNET_NO;
+  cb = ic->callback;
+  cb_cls = ic->callback_cls;
+  if (GNUNET_MESSAGE_TYPE_PEERINFO_INFO_END == ntohs (msg->type))
+  {
+    /* normal end of list of peers, signal end, process next pending request */
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Received end of list of peers from `%s' service\n", "PEERINFO");
+    GNUNET_PEERINFO_iterate_cancel (ic);
+    trigger_transmit (h);
+    if ( (GNUNET_NO == h->in_receive) &&
+        (NULL != h->ic_head) )
+    {
+      h->in_receive = GNUNET_YES;
+      GNUNET_CLIENT_receive (h->client, &peerinfo_handler, h,
+                            GNUNET_TIME_absolute_get_remaining (h->ic_head->timeout));
+    }    
+    if (NULL != cb)
+      cb (cb_cls, NULL, NULL, NULL);
+    return;
+  }
+
   ms = ntohs (msg->size);
   if ((ms < sizeof (struct InfoMessage)) ||
       (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_PEERINFO_INFO))
-    {
-      GNUNET_break (0);
-      reconnect (ic->h);
-      trigger_transmit (ic->h);
-      if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK)
-       GNUNET_SCHEDULER_cancel (ic->timeout_task);
-      if (ic->callback != NULL)
-       ic->callback (ic->callback_cls, NULL, NULL);
-      GNUNET_free (ic);
-      return;
-    }
+  {
+    /* malformed message */
+    GNUNET_break (0);
+    GNUNET_PEERINFO_iterate_cancel (ic);
+    reconnect (h);
+    if (NULL != cb)
+      cb (cb_cls, NULL, NULL,
+         _("Received invalid message from `PEERINFO' service."));
+    return;
+  }
   im = (const struct InfoMessage *) msg;
   GNUNET_break (0 == ntohl (im->reserved));
+  if ( (GNUNET_YES == ic->have_peer) &&
+       (0 != memcmp (&ic->peer, &im->peer, sizeof (struct GNUNET_PeerIdentity))) )
+  {
+    /* bogus message (from a different iteration call?); out of sequence! */
+    LOG (GNUNET_ERROR_TYPE_ERROR,
+         "Received HELLO for peer `%s', expected peer `%s'\n",
+        GNUNET_h2s (&im->peer.hashPubKey),
+        GNUNET_i2s (&ic->peer));
+    
+    GNUNET_break (0);
+    GNUNET_PEERINFO_iterate_cancel (ic);
+    reconnect (h);
+    if (NULL != cb)      
+      cb (cb_cls, NULL, NULL,
+         _("Received invalid message from `PEERINFO' service."));
+    return;
+  }
   hello = NULL;
   if (ms > sizeof (struct InfoMessage) + sizeof (struct GNUNET_MessageHeader))
+  {
+    hello = (const struct GNUNET_HELLO_Message *) &im[1];
+    if (ms != sizeof (struct InfoMessage) + GNUNET_HELLO_size (hello))
+    {
+      /* malformed message */
+      GNUNET_break (0);
+      GNUNET_PEERINFO_iterate_cancel (ic);
+      reconnect (h);
+      if (NULL != cb)      
+        cb (cb_cls, NULL, NULL,
+           _("Received invalid message from `PEERINFO' service."));
+      return;
+    }
+    if (GNUNET_OK != GNUNET_HELLO_get_id (hello, &id))
+    {
+      /* malformed message */
+      GNUNET_break (0);
+      GNUNET_PEERINFO_iterate_cancel (ic);
+      reconnect (h);
+      if (NULL != cb)      
+        cb (cb_cls, NULL, NULL,
+           _("Received invalid message from `PEERINFO' service."));
+      return;
+    }
+    if (0 != memcmp (&im->peer, &id, sizeof (struct GNUNET_PeerIdentity)))
     {
-      hello = (const struct GNUNET_HELLO_Message *) &im[1];
-      if (ms != sizeof (struct InfoMessage) + GNUNET_HELLO_size (hello))
-        {
-         GNUNET_break (0);
-         reconnect (ic->h);
-         trigger_transmit (ic->h);
-         if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK)
-           GNUNET_SCHEDULER_cancel (ic->timeout_task);
-         if (ic->callback != NULL)
-           ic->callback (ic->callback_cls, NULL, NULL);
-         GNUNET_free (ic);
-          return;
-        }
+      /* malformed message */
+      GNUNET_break (0);
+      GNUNET_PEERINFO_iterate_cancel (ic);
+      reconnect (h);
+      if (NULL != cb)      
+        cb (cb_cls, NULL, NULL,
+           _("Received invalid message from `PEERINFO' service."));
+      return;
     }
-#if DEBUG_PEERINFO
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Received %u bytes of `%s' information about peer `%s' from `%s' service\n",
-             (hello == NULL) ? 0 : (unsigned int) GNUNET_HELLO_size (hello),
-             "HELLO",
-             GNUNET_i2s (&im->peer),
-             "PEERINFO");
-#endif
-  ic->h->in_receive = GNUNET_YES;
-  if (ic->callback != NULL)
-    ic->callback (ic->callback_cls, &im->peer, hello);
-  GNUNET_CLIENT_receive (ic->h->client,
-                         &peerinfo_handler,
-                         ic,
+  }
+
+  /* normal data message */
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Received %u bytes of `%s' information about peer `%s' from `%s' service\n",
+       (hello == NULL) ? 0 : (unsigned int) GNUNET_HELLO_size (hello), "HELLO",
+       GNUNET_i2s (&im->peer), "PEERINFO");
+  h->in_receive = GNUNET_YES;
+  GNUNET_CLIENT_receive (h->client, &peerinfo_handler, h,
                          GNUNET_TIME_absolute_get_remaining (ic->timeout));
+  if (NULL != cb)
+    cb (cb_cls, &im->peer, hello, NULL);
 }
 
 
@@ -468,85 +626,73 @@ peerinfo_handler (void *cls, const struct GNUNET_MessageHeader *msg)
  * the results (or handle transmission error).
  *
  * @param cls the 'struct GNUNET_PEERINFO_IteratorContext'
- * @param transmit_success GNUNET_OK if transmission worked
+ * @param emsg error message, NULL if transmission worked
  */
 static void
-iterator_start_receive (void *cls,
-                       int transmit_success)
+iterator_start_receive (void *cls, const char *emsg)
 {
   struct GNUNET_PEERINFO_IteratorContext *ic = cls;
-
-  if (GNUNET_OK != transmit_success)
-    {
-      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                 _("Failed to transmit iteration request to `%s' service (%d).\n"),
-                 "PEERINFO",
-                 transmit_success);
-      if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK)
-       {
-         GNUNET_SCHEDULER_cancel (ic->timeout_task);
-         ic->timeout_task = GNUNET_SCHEDULER_NO_TASK;
-       }
-      reconnect (ic->h);
-      trigger_transmit (ic->h);
-      if (ic->callback != NULL)
-       ic->callback (ic->callback_cls, NULL, NULL);
-      GNUNET_free (ic);
-      return;
-    }  
-#if DEBUG_PEERINFO
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Waiting for response from `%s' service.\n",
-             "PEERINFO");
-#endif
-  ic->h->in_receive = GNUNET_YES;
-  ic->in_receive = GNUNET_YES;
-  ic->tqe = NULL;
-  GNUNET_CLIENT_receive (ic->h->client,
-                         &peerinfo_handler,
-                         ic,
-                         GNUNET_TIME_absolute_get_remaining (ic->timeout));
+  struct GNUNET_PEERINFO_Handle *h = ic->h;
+  GNUNET_PEERINFO_Processor cb;
+  void *cb_cls;
+
+  ic->ac = NULL;
+  if (NULL != emsg)
+  {
+    cb = ic->callback;
+    cb_cls = ic->callback_cls;
+    GNUNET_PEERINFO_iterate_cancel (ic);
+    reconnect (h);
+    if (NULL != cb)
+      cb (cb_cls, NULL, NULL, emsg);
+    return;
+  }
+  LOG (GNUNET_ERROR_TYPE_DEBUG, "Waiting for response from `%s' service.\n",
+       "PEERINFO");
+  ic->request_transmitted = GNUNET_YES;
+  if (GNUNET_NO == h->in_receive)
+  {
+    h->in_receive = GNUNET_YES;
+    GNUNET_CLIENT_receive (h->client, &peerinfo_handler, h,
+                          GNUNET_TIME_absolute_get_remaining (ic->timeout));
+  }
 }
 
 
 /**
- * Peerinfo iteration request has timed out.  
+ * Peerinfo iteration request has timed out.
  *
  * @param cls the 'struct GNUNET_PEERINFO_IteratorContext*'
  * @param tc scheduler context
  */
 static void
-signal_timeout (void *cls,
-               const struct GNUNET_SCHEDULER_TaskContext *tc)
+signal_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct GNUNET_PEERINFO_IteratorContext *ic = cls;
+  GNUNET_PEERINFO_Processor cb;
+  void *cb_cls;
 
-  GNUNET_log (GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK,
-             _("Timeout transmitting iteration request to `%s' service.\n"),
-             "PEERINFO");
   ic->timeout_task = GNUNET_SCHEDULER_NO_TASK;
-  if (! ic->in_receive)
-    GNUNET_CONTAINER_DLL_remove (ic->h->tq_head,
-                                ic->h->tq_tail,
-                                ic->tqe);
-  reconnect (ic->h);
-  ic->callback (ic->callback_cls, NULL, NULL);
-  ic->callback = NULL;
-  GNUNET_free_non_null (ic->tqe);
-  GNUNET_free (ic);
+  cb = ic->callback;
+  cb_cls = ic->callback_cls;
+  GNUNET_PEERINFO_iterate_cancel (ic);
+  if (NULL != cb)
+    cb (cb_cls, NULL, NULL,
+       _("Timeout transmitting iteration request to `PEERINFO' service."));
 }
 
 
 /**
- * Call a method for each known matching host and change its trust
- * value.  The callback method will be invoked once for each matching
- * host and then finally once with a NULL pointer.  After that final
- * invocation, the iterator context must no longer be used.
+ * Call a method for each known matching host.  The callback method
+ * will be invoked once for each matching host and then finally once
+ * with a NULL pointer.  After that final invocation, the iterator
+ * context must no longer be used.
  *
  * Instead of calling this function with 'peer == NULL' it is often
  * better to use 'GNUNET_PEERINFO_notify'.
- * 
+ *
  * @param h handle to the peerinfo service
+ * @param include_friend_only include HELLO messages for friends only
  * @param peer restrict iteration to this peer only (can be NULL)
  * @param timeout how long to wait until timing out
  * @param callback the method to call for each peer
@@ -555,67 +701,65 @@ signal_timeout (void *cls,
  */
 struct GNUNET_PEERINFO_IteratorContext *
 GNUNET_PEERINFO_iterate (struct GNUNET_PEERINFO_Handle *h,
-                        const struct GNUNET_PeerIdentity *peer,
-                        struct GNUNET_TIME_Relative timeout,
-                        GNUNET_PEERINFO_Processor callback,
-                        void *callback_cls)
+                                                                                                int include_friend_only,
+                         const struct GNUNET_PeerIdentity *peer,
+                         struct GNUNET_TIME_Relative timeout,
+                         GNUNET_PEERINFO_Processor callback, void *callback_cls)
 {
-  struct GNUNET_MessageHeader *lapm;
+  struct ListAllPeersMessage *lapm;
   struct ListPeerMessage *lpm;
   struct GNUNET_PEERINFO_IteratorContext *ic;
-  struct TransmissionQueueEntry *tqe;
+  struct GNUNET_PEERINFO_AddContext *ac;
 
-  if (peer == NULL)
-    {
-#if DEBUG_PEERINFO
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                 "Requesting list of peers from PEERINFO service\n");
-#endif
-      tqe = GNUNET_malloc (sizeof (struct TransmissionQueueEntry) +
-                          sizeof (struct GNUNET_MessageHeader));
-      tqe->size = sizeof (struct GNUNET_MessageHeader);
-      lapm = (struct GNUNET_MessageHeader *) &tqe[1];
-      lapm->size = htons (sizeof (struct GNUNET_MessageHeader));
-      lapm->type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET_ALL);
-    }
-  else
-    {
-#if DEBUG_PEERINFO
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                 "Requesting information on peer `%4s' from PEERINFO service\n",
-                 GNUNET_i2s (peer));
-#endif
-      tqe = GNUNET_malloc (sizeof (struct TransmissionQueueEntry) +
-                          sizeof (struct ListPeerMessage));
-      tqe->size = sizeof (struct ListPeerMessage);
-      lpm = (struct ListPeerMessage *) &tqe[1];
-      lpm->header.size = htons (sizeof (struct ListPeerMessage));
-      lpm->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET);
-      memcpy (&lpm->peer, peer, sizeof (struct GNUNET_PeerIdentity));
-    }
   ic = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_IteratorContext));
+  if (NULL == peer)
+  {
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Requesting list of peers from PEERINFO service\n");
+    ac =
+        GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_AddContext) +
+                       sizeof (struct ListAllPeersMessage));
+    ac->size = sizeof (struct ListAllPeersMessage);
+    lapm = (struct ListAllPeersMessage *) &ac[1];
+    lapm->header.size = htons (sizeof (struct ListAllPeersMessage));
+    lapm->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET_ALL);
+    lapm->include_friend_only = htonl (include_friend_only);
+  }
+  else
+  {
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Requesting information on peer `%4s' from PEERINFO service\n",
+         GNUNET_i2s (peer));
+    ac =
+        GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_AddContext) +
+                       sizeof (struct ListPeerMessage));
+    ac->size = sizeof (struct ListPeerMessage);
+    lpm = (struct ListPeerMessage *) &ac[1];
+    lpm->header.size = htons (sizeof (struct ListPeerMessage));
+    lpm->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET);
+    lpm->include_friend_only = htonl (include_friend_only);
+    memcpy (&lpm->peer, peer, sizeof (struct GNUNET_PeerIdentity));
+    ic->have_peer = GNUNET_YES;
+    ic->peer = *peer;
+  }
   ic->h = h;
-  ic->tqe = tqe;
+  ic->ac = ac;
   ic->callback = callback;
   ic->callback_cls = callback_cls;
   ic->timeout = GNUNET_TIME_relative_to_absolute (timeout);
-  ic->timeout_task = GNUNET_SCHEDULER_add_delayed (timeout,
-                                                  &signal_timeout,
-                                                  ic);
-  tqe->timeout = ic->timeout;
-  tqe->cont = &iterator_start_receive;
-  tqe->cont_cls = ic;
-  tqe->timeout = ic->timeout;
-  GNUNET_CONTAINER_DLL_insert_after (h->tq_head,
-                                    h->tq_tail,
-                                    h->tq_tail,
-                                    tqe);
+  ic->timeout_task =
+      GNUNET_SCHEDULER_add_delayed (timeout, &signal_timeout, ic);
+  ac->cont = &iterator_start_receive;
+  ac->cont_cls = ic;
+  GNUNET_CONTAINER_DLL_insert_tail (h->ac_head, h->ac_tail, ac);
+  GNUNET_CONTAINER_DLL_insert_tail (h->ic_head,
+                                   h->ic_tail,
+                                   ic);
   trigger_transmit (h);
   return ic;
 }
 
 
-
 /**
  * Cancel an iteration over peer information.
  *
@@ -624,18 +768,25 @@ GNUNET_PEERINFO_iterate (struct GNUNET_PEERINFO_Handle *h,
 void
 GNUNET_PEERINFO_iterate_cancel (struct GNUNET_PEERINFO_IteratorContext *ic)
 {
-  if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK)
-    {
-      GNUNET_SCHEDULER_cancel (ic->timeout_task);
-      ic->timeout_task = GNUNET_SCHEDULER_NO_TASK;
-    }
+  struct GNUNET_PEERINFO_Handle *h;
+
+  h = ic->h;
+  if (GNUNET_SCHEDULER_NO_TASK != ic->timeout_task)
+  {
+    GNUNET_SCHEDULER_cancel (ic->timeout_task);
+    ic->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  }
   ic->callback = NULL;
-  if (ic->in_receive)
-    return; /* need to finish processing */
-  GNUNET_CONTAINER_DLL_remove (ic->h->tq_head,
-                              ic->h->tq_tail,
-                              ic->tqe);
-  GNUNET_free (ic->tqe);
+  if (GNUNET_YES == ic->request_transmitted)
+    return;                     /* need to finish processing */
+  GNUNET_CONTAINER_DLL_remove (h->ic_head,
+                              h->ic_tail,
+                              ic);
+  if (NULL != ic->ac)
+  {
+    GNUNET_CONTAINER_DLL_remove (h->ac_head, h->ac_tail, ic->ac);
+    GNUNET_free (ic->ac);
+  }
   GNUNET_free (ic);
 }