core changes for topology iteration (get current connections)

1 files changed, 171 insertions, 0 deletions

diff --git a/src/core/core_api_iterate_peers.c b/src/core/core_api_iterate_peers.c
new file mode 100644
index 000000000..08cb9797c
--- /dev/null
+++ b/src/core/core_api_iterate_peers.c
@@ -0,0 +1,171 @@
+/*
+     This file is part of GNUnet.
+     (C) 2009, 2010 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 core/core_api_iterate_peers.c
+ * @brief implementation of the peer_iterate function
+ * @author Christian Grothoff
+ * @author Nathan Evans
+ */
+#include "platform.h"
+#include "gnunet_core_service.h"
+#include "core.h"
+
+
+struct GNUNET_CORE_RequestContext
+{
+  
+  /**
+   * Our connection to the service.
+   */
+  struct GNUNET_CLIENT_Connection *client;
+
+  /**
+   * Handle for transmitting a request.
+   */
+  struct GNUNET_CLIENT_TransmitHandle *th;
+
+  /**
+   * Function called with the peer.
+   */
+  GNUNET_CORE_ConnectEventHandler peer_cb;
+
+  /**
+   * Closure for peer_cb.
+   */
+  void *cb_cls;
+
+};
+
+
+/**
+ * Receive reply from core service with information about a peer.
+ *
+ * @param cls our 'struct  GNUNET_CORE_RequestContext *'
+ * @param msg NULL on error or last entry
+ */
+static void
+receive_info (void *cls,
+              const struct GNUNET_MessageHeader *msg)
+{
+  struct GNUNET_CORE_RequestContext *request_context = cls;
+  const struct ConnectNotifyMessage *connect_message;
+
+
+  /* Handle last message or error case, disconnect and clean up */
+  if ( (msg == NULL) ||
+      ((ntohs (msg->type) == GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT) &&
+      (ntohs (msg->size) == sizeof (struct GNUNET_MessageHeader))) )
+    {
+      if (request_context->peer_cb != NULL)
+        request_context->peer_cb (request_context->cb_cls,
+                               NULL, GNUNET_TIME_relative_get_zero(), 0);
+      GNUNET_CLIENT_disconnect (request_context->client, GNUNET_NO);
+      GNUNET_free (request_context);
+      return;
+    }
+
+  /* Handle incorrect message type or size, disconnect and clean up */
+  if ( (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_CORE_NOTIFY_CONNECT) ||
+       (ntohs (msg->size) != sizeof (struct ConnectNotifyMessage)) )
+    {
+      GNUNET_break (0);
+      if (request_context->peer_cb != NULL)
+        request_context->peer_cb (request_context->cb_cls,
+                               NULL, GNUNET_TIME_relative_get_zero(), 0);
+      GNUNET_CLIENT_disconnect (request_context->client, GNUNET_NO);
+      GNUNET_free (request_context);
+      return;
+    }
+
+  /* Normal case */
+  connect_message = (const struct ConnectNotifyMessage *) msg;
+  if (request_context->peer_cb != NULL)
+    request_context->peer_cb (request_context->cb_cls,
+                           &connect_message->peer,
+                           GNUNET_TIME_relative_ntoh(connect_message->latency),
+                           ntohl (connect_message->distance));
+
+  GNUNET_CLIENT_receive(request_context->client, &receive_info, request_context, GNUNET_TIME_relative_get_forever());
+}
+
+/**
+ * Function called to notify a client about the socket
+ * begin ready to queue more data.  "buf" will be
+ * NULL and "size" zero if the socket was closed for
+ * writing in the meantime.
+ *
+ * @param cls closure
+ * @param size number of bytes available in buf
+ * @param buf where the callee should write the message
+ * @return number of bytes written to buf
+ */
+static size_t
+transmit_request(void *cls,
+                 size_t size, void *buf)
+{
+  struct GNUNET_MessageHeader *msg;
+  if ((size < sizeof(struct GNUNET_MessageHeader)) || (buf == NULL))
+    return 0;
+
+  msg = (struct GNUNET_MessageHeader *)buf;
+  msg->size = htons (sizeof (struct GNUNET_MessageHeader));
+  msg->type = htons (GNUNET_MESSAGE_TYPE_CORE_ITERATE_PEERS);
+  return sizeof(struct GNUNET_MessageHeader);
+}
+
+/**
+ * Obtain statistics and/or change preferences for the given peer.
+ *
+ * @param sched scheduler to use
+ * @param cfg configuration to use
+ * @param peer_cb function to call with the peer information
+ * @param cb_cls closure for peer_cb
+ * @return GNUNET_OK if iterating, GNUNET_SYSERR on error
+ */
+int
+GNUNET_CORE_iterate_peers (struct GNUNET_SCHEDULER_Handle *sched,
+                           const struct GNUNET_CONFIGURATION_Handle *cfg,
+                           GNUNET_CORE_ConnectEventHandler peer_cb,
+                           void *cb_cls)
+{
+  struct GNUNET_CORE_RequestContext *request_context;
+  struct GNUNET_CLIENT_Connection *client;
+
+  client = GNUNET_CLIENT_connect (sched, "core", cfg);
+  if (client == NULL)
+    return GNUNET_SYSERR;
+  request_context = GNUNET_malloc (sizeof (struct GNUNET_CORE_RequestContext));
+  request_context->client = client;
+  request_context->peer_cb = peer_cb;
+  request_context->cb_cls = cb_cls;
+
+  /*GNUNET_assert (GNUNET_OK == GNUNET_CLIENT_transmit_and_get_response (client,
+                                                                       &request_message,
+                                                                       GNUNET_TIME_relative_get_forever(),
+                                                                       GNUNET_YES,
+                                                                       &receive_info,
+                                                                       request_context));*/
+  request_context->th = GNUNET_CLIENT_notify_transmit_ready(client, sizeof(struct GNUNET_MessageHeader), GNUNET_TIME_relative_get_forever(), GNUNET_YES, &transmit_request, NULL);
+  GNUNET_CLIENT_receive(client, &receive_info, request_context, GNUNET_TIME_relative_get_forever());
+  return GNUNET_OK;
+}
+
+/* end of core_api_iterate_peers.c */