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3 (C) 2009, 2010, 2012, 2013 Christian Grothoff (and other contributing authors)
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22 * @file arm/arm_monitor_api.c
23 * @brief API for monitoring the ARM service
24 * @author Christian Grothoff, LRN
27 #include "gnunet_arm_service.h"
28 #include "gnunet_util_lib.h"
29 #include "gnunet_protocols.h"
32 #define INIT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
34 #define LOG(kind,...) GNUNET_log_from (kind, "arm-monitor-api",__VA_ARGS__)
37 * Handle for interacting with ARM.
39 struct GNUNET_ARM_MonitorHandle
43 * Our control connection to the ARM service.
45 struct GNUNET_CLIENT_Connection *monitor;
48 * The configuration that we are using.
50 struct GNUNET_CONFIGURATION_Handle *cfg;
53 * Handle for our current transmission request.
55 struct GNUNET_CLIENT_TransmitHandle *cth;
58 * ID of the reconnect task (if any).
60 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
63 * Current delay we use for re-trying to connect to core.
65 struct GNUNET_TIME_Relative retry_backoff;
68 * Are we currently disconnected and hence unable to send?
70 unsigned char currently_down;
73 * Callback to invoke on status updates.
75 GNUNET_ARM_ServiceStatusCallback service_status;
78 * Closure for service_status.
83 * ID of a task to run if we fail to get a reply to the init message in time.
85 GNUNET_SCHEDULER_TaskIdentifier init_timeout_task_id;
89 monitor_notify_handler (void *cls, const struct GNUNET_MessageHeader *msg);
92 reconnect_arm_monitor (struct GNUNET_ARM_MonitorHandle *h);
95 * Task scheduled to try to re-connect to arm.
97 * @param cls the 'struct GNUNET_ARM_MonitorHandle'
98 * @param tc task context
101 reconnect_arm_monitor_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
103 struct GNUNET_ARM_MonitorHandle *h = cls;
105 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
106 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to ARM service for monitoring after delay\n");
107 reconnect_arm_monitor (h);
112 * Close down any existing connection to the ARM service and
113 * try re-establishing it later.
115 * @param h our handle
118 reconnect_arm_monitor_later (struct GNUNET_ARM_MonitorHandle *h)
122 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
126 if (NULL != h->monitor)
128 GNUNET_CLIENT_disconnect (h->monitor);
132 if (GNUNET_SCHEDULER_NO_TASK != h->init_timeout_task_id)
134 GNUNET_SCHEDULER_cancel (h->init_timeout_task_id);
135 h->init_timeout_task_id = GNUNET_SCHEDULER_NO_TASK;
138 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == h->reconnect_task);
140 GNUNET_SCHEDULER_add_delayed (h->retry_backoff, &reconnect_arm_monitor_task, h);
142 h->retry_backoff = GNUNET_TIME_STD_BACKOFF (h->retry_backoff);
147 * Init message timed out. Disconnect and try again.
149 * @param cls arm monitor handle
150 * @param tc task context
153 init_timeout_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
155 struct GNUNET_ARM_MonitorHandle *h = cls;
156 LOG (GNUNET_ERROR_TYPE_DEBUG,
157 "Init message timed out\n");
159 reconnect_arm_monitor_later (h);
164 * Transmit the monitoring initialization message to the arm service.
166 * @param cls closure with the 'struct GNUNET_ARM_MonitorHandle'
167 * @param size number of bytes available in buf
168 * @param buf where the callee should write the message
169 * @return number of bytes written to buf
172 transmit_monitoring_init_message (void *cls, size_t size, void *buf)
174 struct GNUNET_ARM_MonitorHandle *h = cls;
175 struct GNUNET_MessageHeader *msg;
178 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == h->reconnect_task);
179 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == h->init_timeout_task_id);
183 LOG (GNUNET_ERROR_TYPE_DEBUG,
184 "Transmission failed, initiating reconnect\n");
185 reconnect_arm_monitor_later (h);
188 msize = sizeof (struct GNUNET_MessageHeader);
191 LOG (GNUNET_ERROR_TYPE_DEBUG,
192 "Request is too big (%u < %u), not sending it\n", size, msize);
193 h->cth = GNUNET_CLIENT_notify_transmit_ready (h->monitor, msize,
194 GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_NO,
195 transmit_monitoring_init_message, h);
200 msg->size = htons (msize);
201 msg->type = htons (GNUNET_MESSAGE_TYPE_ARM_MONITOR);
202 LOG (GNUNET_ERROR_TYPE_DEBUG,
203 "Transmitting ARM monitoring init message with %u bytes to arm.\n",
204 (unsigned int) msize);
206 h->init_timeout_task_id = GNUNET_SCHEDULER_add_delayed (
207 INIT_TIMEOUT, init_timeout_task, h);
208 GNUNET_CLIENT_receive (h->monitor, &monitor_notify_handler, h,
209 GNUNET_TIME_UNIT_FOREVER_REL);
215 reconnect_arm_monitor (struct GNUNET_ARM_MonitorHandle *h)
217 GNUNET_assert (NULL == h->monitor);
218 h->monitor = GNUNET_CLIENT_connect ("arm", h->cfg);
219 if (NULL == h->monitor)
221 LOG (GNUNET_ERROR_TYPE_DEBUG,
222 "arm_api, GNUNET_CLIENT_connect returned NULL\n");
223 if (NULL != h->service_status)
224 h->service_status (h->cls, h, NULL, GNUNET_ARM_SERVICE_STOPPED);
225 return GNUNET_SYSERR;
227 LOG (GNUNET_ERROR_TYPE_DEBUG,
228 "arm_api, GNUNET_CLIENT_connect returned non-NULL\n");
229 h->cth = GNUNET_CLIENT_notify_transmit_ready (h->monitor,
230 sizeof (struct GNUNET_MessageHeader), GNUNET_TIME_UNIT_FOREVER_REL,
231 GNUNET_NO, &transmit_monitoring_init_message, h);
237 * Setup a context for monitoring ARM, then
238 * start connecting to the ARM service for monitoring using that context.
240 * @param cfg configuration to use (needed to contact ARM;
241 * the ARM service may internally use a different
242 * configuration to determine how to start the service).
243 * @param cont callback to invoke on status updates
244 * @param cont_cls closure
245 * @return context to use for further ARM monitor operations, NULL on error.
247 struct GNUNET_ARM_MonitorHandle *
248 GNUNET_ARM_monitor (const struct GNUNET_CONFIGURATION_Handle *cfg,
249 GNUNET_ARM_ServiceStatusCallback cont, void *cont_cls)
251 struct GNUNET_ARM_MonitorHandle *h;
253 h = GNUNET_malloc (sizeof (struct GNUNET_ARM_MonitorHandle));
254 h->cfg = GNUNET_CONFIGURATION_dup (cfg);
255 h->currently_down = GNUNET_YES;
256 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
257 h->init_timeout_task_id = GNUNET_SCHEDULER_NO_TASK;
258 h->service_status = cont;
260 if (GNUNET_OK != reconnect_arm_monitor (h))
270 * Disconnect from the ARM service (if connected) and destroy the context.
271 * Don't call inside a callback!
273 * @param h the handle that was being used
276 GNUNET_ARM_monitor_disconnect_and_free (struct GNUNET_ARM_MonitorHandle *handle)
278 LOG (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting from ARM service\n");
279 if (NULL != handle->cth)
281 GNUNET_CLIENT_notify_transmit_ready_cancel (handle->cth);
284 if (GNUNET_SCHEDULER_NO_TASK != handle->init_timeout_task_id)
286 GNUNET_SCHEDULER_cancel (handle->init_timeout_task_id);
287 handle->init_timeout_task_id = GNUNET_SCHEDULER_NO_TASK;
289 if (NULL != handle->monitor)
291 GNUNET_CLIENT_disconnect (handle->monitor);
292 handle->monitor = NULL;
294 if (GNUNET_SCHEDULER_NO_TASK != handle->reconnect_task)
296 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
297 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
299 GNUNET_CONFIGURATION_destroy (handle->cfg);
300 GNUNET_free (handle);
305 * Handler for notification messages received from ARM.
307 * @param cls our "struct GNUNET_ARM_MonitorHandle"
308 * @param msg the message received from the arm service
311 monitor_notify_handler (void *cls, const struct GNUNET_MessageHeader *msg)
313 struct GNUNET_ARM_MonitorHandle *h = cls;
315 const struct GNUNET_ARM_StatusMessage *res;
316 enum GNUNET_ARM_ServiceStatus status;
320 LOG (GNUNET_ERROR_TYPE_INFO,
321 _("Monitoring client was disconnected from arm service, trying to reconnect.\n"));
322 reconnect_arm_monitor_later (h);
325 msize = ntohs (msg->size);
326 LOG (GNUNET_ERROR_TYPE_DEBUG,
327 "Processing message of type %u and size %u from arm service\n",
328 ntohs (msg->type), msize);
329 switch (ntohs (msg->type))
331 case GNUNET_MESSAGE_TYPE_ARM_STATUS:
332 if (msize <= sizeof (struct GNUNET_ARM_StatusMessage))
335 reconnect_arm_monitor_later (h);
338 if (GNUNET_SCHEDULER_NO_TASK != h->init_timeout_task_id)
340 GNUNET_SCHEDULER_cancel (h->init_timeout_task_id);
341 h->init_timeout_task_id = GNUNET_SCHEDULER_NO_TASK;
343 res = (const struct GNUNET_ARM_StatusMessage *) msg;
344 LOG (GNUNET_ERROR_TYPE_DEBUG,
345 "Received response from ARM for service `%s': %u\n",
346 (const char *) &res[1], ntohs (msg->type));
347 status = (enum GNUNET_ARM_ServiceStatus) ntohl (res->status);
348 if ((NULL != h->service_status))
349 h->service_status (h->cls, h, (const char *) &res[1], status);
352 reconnect_arm_monitor_later (h);
355 GNUNET_CLIENT_receive (h->monitor, &monitor_notify_handler, h,
356 GNUNET_TIME_UNIT_FOREVER_REL);
360 /* end of arm_api.c */