transport_api_hello_get.c

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/*
     This file is part of GNUnet.
     Copyright (C) 2009-2013, 2016 GNUnet e.V.
 
     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     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
     Affero General Public License for more details.
 
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
     SPDX-License-Identifier: AGPL3.0-or-later
 */
 
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_constants.h"
#include "gnunet_arm_service.h"
#include "gnunet_hello_lib.h"
#include "gnunet_protocols.h"
#include "gnunet_transport_hello_service.h"
#include "transport.h"
 
 
struct GNUNET_TRANSPORT_HelloGetHandle
{
  const struct GNUNET_CONFIGURATION_Handle *cfg;
 
  struct GNUNET_MQ_Handle *mq;
 
  GNUNET_TRANSPORT_HelloUpdateCallback rec;
 
  void *rec_cls;
 
  struct GNUNET_SCHEDULER_Task *notify_task;
 
  struct GNUNET_SCHEDULER_Task *reconnect_task;
 
  struct GNUNET_TIME_Relative reconnect_delay;
 
  enum GNUNET_TRANSPORT_AddressClass ac;
};
 
 
static int
check_hello (void *cls,
             const struct GNUNET_MessageHeader *msg)
{
  struct GNUNET_PeerIdentity me;
 
  if (GNUNET_OK !=
      GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg,
                           &me))
  {
    GNUNET_break (0);
    return GNUNET_SYSERR;
  }
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Receiving (my own) HELLO message (%u bytes), I am `%s'.\n",
              (unsigned int) ntohs (msg->size),
              GNUNET_i2s (&me));
  return GNUNET_OK;
}
 
 
static void
handle_hello (void *cls,
              const struct GNUNET_MessageHeader *msg)
{
  struct GNUNET_TRANSPORT_HelloGetHandle *ghh = cls;
 
  ghh->rec (ghh->rec_cls,
            msg);
}
 
 
static void
schedule_reconnect (struct GNUNET_TRANSPORT_HelloGetHandle *ghh);
 
 
static void
mq_error_handler (void *cls,
                  enum GNUNET_MQ_Error error)
{
  struct GNUNET_TRANSPORT_HelloGetHandle *ghh = cls;
 
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Error receiving from transport service, disconnecting temporarily.\n");
  GNUNET_MQ_destroy (ghh->mq);
  ghh->mq = NULL;
  schedule_reconnect (ghh);
}
 
 
static void
reconnect (void *cls)
{
  struct GNUNET_TRANSPORT_HelloGetHandle *ghh = cls;
  struct GNUNET_MQ_MessageHandler handlers[] = {
    GNUNET_MQ_hd_var_size (hello,
                           GNUNET_MESSAGE_TYPE_HELLO,
                           struct GNUNET_MessageHeader,
                           ghh),
    GNUNET_MQ_handler_end ()
  };
  struct GNUNET_MQ_Envelope *env;
  struct StartMessage *s;
 
  ghh->reconnect_task = NULL;
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Connecting to transport service.\n");
  GNUNET_assert (NULL == ghh->mq);
  ghh->mq = GNUNET_CLIENT_connect (ghh->cfg,
                                   "transport",
                                   handlers,
                                   &mq_error_handler,
                                   ghh);
  if (NULL == ghh->mq)
    return;
  env = GNUNET_MQ_msg (s,
                       GNUNET_MESSAGE_TYPE_TRANSPORT_START);
  s->options = htonl (0);
  GNUNET_MQ_send (ghh->mq,
                  env);
}
 
 
static void
schedule_reconnect (struct GNUNET_TRANSPORT_HelloGetHandle *ghh)
{
  ghh->reconnect_task =
    GNUNET_SCHEDULER_add_delayed (ghh->reconnect_delay,
                                  &reconnect,
                                  ghh);
  ghh->reconnect_delay = GNUNET_TIME_STD_BACKOFF (ghh->reconnect_delay);
}
 
 
struct GNUNET_TRANSPORT_HelloGetHandle *
GNUNET_TRANSPORT_hello_get (const struct GNUNET_CONFIGURATION_Handle *cfg,
                            enum GNUNET_TRANSPORT_AddressClass ac,
                            GNUNET_TRANSPORT_HelloUpdateCallback rec,
                            void *rec_cls)
{
  struct GNUNET_TRANSPORT_HelloGetHandle *ghh;
 
  ghh = GNUNET_new (struct GNUNET_TRANSPORT_HelloGetHandle);
  ghh->rec = rec;
  ghh->rec_cls = rec_cls;
  ghh->cfg = cfg;
  ghh->ac = ac;
  reconnect (ghh);
  if (NULL == ghh->mq)
  {
    GNUNET_free (ghh);
    return NULL;
  }
  return ghh;
}
 
 
void
GNUNET_TRANSPORT_hello_get_cancel (struct GNUNET_TRANSPORT_HelloGetHandle *ghh)
{
  if (NULL != ghh->reconnect_task)
  {
    GNUNET_SCHEDULER_cancel (ghh->reconnect_task);
    ghh->reconnect_task = NULL;
  }
  if (NULL != ghh->mq)
  {
    GNUNET_MQ_destroy (ghh->mq);
    ghh->mq = NULL;
  }
  GNUNET_free (ghh);
}
 
 
/* end of transport_api_hello_get.c */