2 This file is part of GNUnet.
3 (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
23 * @brief api to get information from the network size estimation service
24 * @author Nathan Evans
27 #include "gnunet_client_lib.h"
28 #include "gnunet_constants.h"
29 #include "gnunet_container_lib.h"
30 #include "gnunet_arm_service.h"
31 #include "gnunet_hello_lib.h"
32 #include "gnunet_protocols.h"
33 #include "gnunet_server_lib.h"
34 #include "gnunet_time_lib.h"
35 #include "gnunet_nse_service.h"
40 * Handle for the service.
42 struct GNUNET_NSE_Handle
45 * Configuration to use.
47 const struct GNUNET_CONFIGURATION_Handle *cfg;
50 * Socket (if available).
52 struct GNUNET_CLIENT_Connection *client;
55 * Currently pending transmission request.
57 struct GNUNET_CLIENT_TransmitHandle *th;
60 * Task doing exponential back-off trying to reconnect.
62 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
65 * Time for next connect retry.
67 struct GNUNET_TIME_Relative reconnect_delay;
70 * Callback function to call when message is received.
72 GNUNET_NSE_Callback recv_cb;
75 * Closure to pass to callback.
83 * Try again to connect to network size estimation service.
85 * @param cls the handle to the transport service
86 * @param tc scheduler context
90 const struct GNUNET_SCHEDULER_TaskContext *tc);
94 * Type of a function to call when we receive a message
98 * @param msg message received, NULL on timeout or fatal error
101 message_handler (void *cls,
102 const struct GNUNET_MessageHeader * msg)
104 struct GNUNET_NSE_Handle *h = cls;
105 const struct GNUNET_NSE_ClientMessage *client_msg;
109 /* Error, timeout, death */
110 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
112 h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->reconnect_delay,
117 if ( (ntohs (msg->size) != sizeof(struct GNUNET_NSE_ClientMessage)) ||
118 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_NSE_ESTIMATE) )
123 client_msg = (const struct GNUNET_NSE_ClientMessage *)msg;
124 h->recv_cb (h->recv_cb_cls,
125 client_msg->size_estimate,
126 client_msg->std_deviation);
127 GNUNET_CLIENT_receive (h->client,
130 GNUNET_TIME_UNIT_FOREVER_REL);
136 * Reschedule a connect attempt to the service.
138 * @param h transport service to reconnect
141 reschedule_connect (struct GNUNET_NSE_Handle *h)
143 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
147 GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
150 if (NULL != h->client)
152 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
157 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
158 "Scheduling task to reconnect to nse service in %llu ms.\n",
159 h->reconnect_delay.rel_value);
162 = GNUNET_SCHEDULER_add_delayed (h->reconnect_delay,
164 if (h->reconnect_delay.rel_value == 0)
166 h->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
170 h->reconnect_delay = GNUNET_TIME_relative_multiply (h->reconnect_delay, 2);
171 h->reconnect_delay = GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS,
178 * Transmit START message to service.
181 * @param size number of bytes available in buf
182 * @param buf where to copy the message
183 * @return number of bytes copied to buf
186 send_start (void *cls, size_t size, void *buf)
188 struct GNUNET_NSE_Handle *h = cls;
189 struct GNUNET_MessageHeader *msg;
194 /* Connect error... */
196 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
197 "Shutdown while trying to transmit `%s' request.\n",
200 reschedule_connect(h);
204 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
205 "Transmitting `%s' request.\n", "START");
207 GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
209 msg = (struct GNUNET_MessageHeader *)buf;
210 msg->size = htons (sizeof (struct GNUNET_MessageHeader));
211 msg->type = htons (GNUNET_MESSAGE_TYPE_NSE_START);
212 GNUNET_CLIENT_receive (h->client,
213 &message_handler, h, GNUNET_TIME_UNIT_FOREVER_REL);
214 return sizeof (struct GNUNET_MessageHeader);
219 * Try again to connect to network size estimation service.
221 * @param cls the handle to the transport service
222 * @param tc scheduler context
225 reconnect (void *cls,
226 const struct GNUNET_SCHEDULER_TaskContext *tc)
228 struct GNUNET_NSE_Handle *h = cls;
230 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
231 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
233 /* shutdown, just give up */
237 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
238 "Connecting to network size estimation service.\n");
240 GNUNET_assert (h->client == NULL);
241 h->client = GNUNET_CLIENT_connect ("nse", h->cfg);
242 GNUNET_assert (h->client != NULL);
245 GNUNET_CLIENT_notify_transmit_ready (h->client,
246 sizeof(struct GNUNET_MessageHeader),
247 GNUNET_TIME_UNIT_FOREVER_REL,
251 GNUNET_assert(h->th != NULL);
256 * Connect to the network size estimation service.
258 * @param cfg the configuration to use
259 * @param func funtion to call with network size estimate
260 * @param func_cls closure to pass for network size estimate callback
262 * @return handle to use
264 struct GNUNET_NSE_Handle *
265 GNUNET_NSE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
266 GNUNET_NSE_Callback func, void *func_cls)
268 struct GNUNET_NSE_Handle *ret;
270 GNUNET_assert (func != NULL);
271 ret = GNUNET_malloc (sizeof (struct GNUNET_NSE_Handle));
274 ret->recv_cb_cls = func_cls;
275 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
276 ret->reconnect_task = GNUNET_SCHEDULER_add_now (&reconnect, ret);
282 * Disconnect from network size estimation service
284 * @param h handle to destroy
287 GNUNET_NSE_disconnect (struct GNUNET_NSE_Handle *h)
289 GNUNET_assert(h != NULL);
290 if (h->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
292 GNUNET_SCHEDULER_cancel(h->reconnect_task);
293 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
297 GNUNET_CLIENT_notify_transmit_ready_cancel(h->th);
300 if (h->client != NULL)
302 GNUNET_CLIENT_disconnect(h->client, GNUNET_NO);
308 /* end of nse_api.c */