track HELLOs from peerinfo

1 files changed, 139 insertions, 0 deletions

diff --git a/src/dht/gnunet-service-dht_hello.c b/src/dht/gnunet-service-dht_hello.c
new file mode 100644
index 000000000..2ee60c91f
--- /dev/null
+++ b/src/dht/gnunet-service-dht_hello.c
@@ -0,0 +1,139 @@
+/*
+     This file is part of GNUnet.
+     (C) 2011 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
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file dht/gnunet-service-dht_hello.c
+ * @brief GNUnet DHT integration with peerinfo
+ * @author Christian Grothoff
+ *
+ * TODO:
+ * - consider adding mechanism to remove expired HELLOs
+ */
+#include "platform.h"
+#include "gnunet-service-dht.h"
+#include "gnunet-service-dht_hello.h"
+#include "gnunet_peerinfo_service.h"
+
+
+/**
+ * Handle for peerinfo notifications.
+ */
+static struct GNUNET_PEERINFO_NotifyContext *pnc;
+
+/**
+ * Hash map of peers to HELLOs.
+ */
+static struct GNUNET_CONTAINER_MultiHashMap *peer_to_hello;
+
+
+/**
+ * Obtain a peer's HELLO if available
+ *
+ * @param peer peer to look for a HELLO from
+ * @return HELLO for the given peer
+ */
+const struct GNUNET_HELLO_Message *
+GDS_HELLO_get (const struct GNUNET_PeerIdentity *peer)
+{
+  return GNUNET_CONTAINER_multihashmap_get (peer_to_hello,
+                                            &peer->hashPubKey);
+}
+
+
+/**
+ * Function called for each HELLO known to PEERINFO.
+ *
+ * @param cls closure
+ * @param peer id of the peer, NULL for last call
+ * @param hello hello message for the peer (can be NULL)
+ * @param error message
+ */
+static void
+process_hello (void *cls,
+               const struct GNUNET_PeerIdentity *
+               peer,
+               const struct GNUNET_HELLO_Message *
+               hello, const char *err_msg)
+{
+  struct GNUNET_TIME_Absolute ex;
+  struct GNUNET_HELLO_Message *hm;
+
+  if (hello == NULL)
+    return;
+  ex = GNUNET_HELLO_get_last_expiration (hello);
+  if (GNUNET_TIME_absolute_get_remaining (ex).rel_value == 0)
+    return;
+  hm = GNUNET_CONTAINER_multihashmap_get (peer_to_hello,
+                                          &peer->hashPubKey);
+  GNUNET_free_non_null (hm);
+  hm = GNUNET_malloc (GNUNET_HELLO_size (hello));
+  memcpy (hm, hello, GNUNET_HELLO_size (hello));
+  GNUNET_assert (GNUNET_SYSERR !=
+                 GNUNET_CONTAINER_multihashmap_put (peer_to_hello,
+                                                    &peer->hashPubKey,
+                                                    hm,
+                                                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE));
+}
+
+
+/**
+ * Initialize HELLO subsystem.
+ */
+void
+GDS_HELLO_init ()
+{
+  pnc = GNUNET_PEERINFO_notify (GDS_cfg,
+                                &process_hello,
+                                NULL);
+  peer_to_hello = GNUNET_CONTAINER_multihashmap_create (256);
+}
+
+
+/**
+ * Free memory occopied by the HELLO.
+ */
+static int
+free_hello (void *cls,
+            const GNUNET_HashCode *key,
+            void *hello)
+{
+  GNUNET_free (hello);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Shutdown HELLO subsystem.
+ */
+void
+GDS_HELLO_done ()
+{
+  if (NULL != pnc)
+  {
+    GNUNET_PEERINFO_notify_cancel (pnc);
+    pnc = NULL;
+  }
+  GNUNET_CONTAINER_multihashmap_iterate (peer_to_hello,
+                                         &free_hello,
+                                         NULL);
+  GNUNET_CONTAINER_multihashmap_destroy (peer_to_hello);
+}
+
+/* end of gnunet-service-dht_hello.c */