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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.
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18 Boston, MA 02110-1301, USA.
22 * @file util/resolver_api.c
23 * @brief resolver for writing a tool
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_protocols.h"
29 #include "gnunet_resolver_service.h"
32 #define LOG(kind,...) GNUNET_log_from (kind, "resolver-api", __VA_ARGS__)
34 #define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "resolver-api", syscall)
37 * Maximum supported length for a hostname
39 #define MAX_HOSTNAME 1024
43 * Possible hostnames for "loopback".
45 static const char *loopback[] = {
55 static const struct GNUNET_CONFIGURATION_Handle *resolver_cfg;
58 * Our connection to the resolver service, created on-demand, but then
59 * persists until error or shutdown.
61 static struct GNUNET_MQ_Handle *mq;
64 * Head of DLL of requests.
66 static struct GNUNET_RESOLVER_RequestHandle *req_head;
69 * Tail of DLL of requests.
71 static struct GNUNET_RESOLVER_RequestHandle *req_tail;
74 * How long should we wait to reconnect?
76 static struct GNUNET_TIME_Relative backoff;
79 * Task for reconnecting.
81 static struct GNUNET_SCHEDULER_Task *r_task;
84 * Task ID of shutdown task; only present while we have a
85 * connection to the resolver service.
87 static struct GNUNET_SCHEDULER_Task *s_task;
91 * Handle to a request given to the resolver. Can be used to cancel
92 * the request prior to the timeout or successful execution. Also
93 * used to track our internal state for the request.
95 struct GNUNET_RESOLVER_RequestHandle
99 * Next entry in DLL of requests.
101 struct GNUNET_RESOLVER_RequestHandle *next;
104 * Previous entry in DLL of requests.
106 struct GNUNET_RESOLVER_RequestHandle *prev;
109 * Callback if this is an name resolution request,
112 GNUNET_RESOLVER_AddressCallback addr_callback;
115 * Callback if this is a reverse lookup request,
118 GNUNET_RESOLVER_HostnameCallback name_callback;
121 * Closure for the callbacks.
126 * When should this request time out?
128 struct GNUNET_TIME_Absolute timeout;
131 * Task handle for making reply callbacks in numeric lookups
132 * asynchronous, and for timeout handling.
134 struct GNUNET_SCHEDULER_Task *task;
137 * Desired address family.
142 * Has this request been transmitted to the service?
143 * #GNUNET_YES if transmitted
144 * #GNUNET_YES if not transmitted
145 * #GNUNET_SYSERR when request was canceled
150 * Did we add this request to the queue?
155 * Desired direction (IP to name or name to IP)
160 * #GNUNET_YES if a response was received
162 int received_response;
165 * Length of the data that follows this struct.
172 * Check that the resolver service runs on localhost
175 * @return #GNUNET_OK if the resolver is properly configured,
176 * #GNUNET_SYSERR otherwise.
183 struct sockaddr_in v4;
184 struct sockaddr_in6 v6;
186 memset (&v4, 0, sizeof (v4));
187 v4.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
188 v4.sin_family = AF_INET;
189 #if HAVE_SOCKADDR_IN_SIN_LEN
190 v4.sin_len = sizeof (v4);
192 memset (&v6, 0, sizeof (v6));
193 v6.sin6_family = AF_INET6;
194 #if HAVE_SOCKADDR_IN_SIN_LEN
195 v6.sin6_len = sizeof (v6);
198 GNUNET_CONFIGURATION_get_value_string (resolver_cfg,
203 LOG (GNUNET_ERROR_TYPE_INFO,
204 _("Missing `%s' for `%s' in configuration, DNS resolution will be unavailable.\n"),
207 return GNUNET_SYSERR;
209 if ((1 == inet_pton (AF_INET, hostname, &v4)) ||
210 (1 == inet_pton (AF_INET6, hostname, &v6)))
212 GNUNET_free (hostname);
216 while (NULL != loopback[i])
217 if (0 == strcasecmp (loopback[i++], hostname))
219 GNUNET_free (hostname);
222 LOG (GNUNET_ERROR_TYPE_INFO,
223 _("Missing `%s' or numeric IP address for `%s' of `%s' in configuration, DNS resolution will be unavailable.\n"),
227 GNUNET_free (hostname);
228 return GNUNET_SYSERR;
233 * Create the connection to the resolver service.
235 * @param cfg configuration to use
238 GNUNET_RESOLVER_connect (const struct GNUNET_CONFIGURATION_Handle *cfg)
240 GNUNET_assert (NULL != cfg);
241 backoff = GNUNET_TIME_UNIT_MILLISECONDS;
247 * Destroy the connection to the resolver service.
250 GNUNET_RESOLVER_disconnect ()
252 GNUNET_assert (NULL == req_head);
253 GNUNET_assert (NULL == req_tail);
256 LOG (GNUNET_ERROR_TYPE_DEBUG,
257 "Disconnecting from DNS service\n");
258 GNUNET_MQ_destroy (mq);
263 GNUNET_SCHEDULER_cancel (r_task);
268 GNUNET_SCHEDULER_cancel (s_task);
275 * Convert IP address to string without DNS resolution.
277 * @param af address family
278 * @param ip the address
279 * @param ip_len number of bytes in @a ip
280 * @return address as a string, NULL on error
287 char buf[INET6_ADDRSTRLEN];
292 if (ip_len != sizeof (struct in_addr))
295 inet_ntop (AF_INET, ip, buf, sizeof (buf)))
297 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
303 if (ip_len != sizeof (struct in6_addr))
306 inet_ntop (AF_INET6, ip, buf, sizeof (buf)))
308 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
317 return GNUNET_strdup (buf);
322 * Adjust exponential back-off and reconnect to the service.
329 * Generic error handler, called with the appropriate error code and
330 * the same closure specified at the creation of the message queue.
331 * Not every message queue implementation supports an error handler.
334 * @param error error code
337 mq_error_handler (void *cls,
338 enum GNUNET_MQ_Error error)
340 GNUNET_MQ_destroy (mq);
347 * Task executed on system shutdown.
350 shutdown_task (void *cls)
353 GNUNET_RESOLVER_disconnect ();
354 backoff = GNUNET_TIME_UNIT_MILLISECONDS;
359 * Process pending requests to the resolver.
364 struct GNUNET_RESOLVER_GetMessage *msg;
365 struct GNUNET_MQ_Envelope *env;
366 struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
375 /* nothing to do, release socket really soon if there is nothing
376 * else happening... */
378 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS,
383 if (GNUNET_NO != rh->was_transmitted)
384 return; /* waiting for reply */
385 env = GNUNET_MQ_msg_extra (msg,
387 GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST);
388 msg->direction = htonl (rh->direction);
389 msg->af = htonl (rh->af);
393 LOG (GNUNET_ERROR_TYPE_DEBUG,
394 "Transmitting DNS resolution request to DNS service\n");
397 rh->was_transmitted = GNUNET_YES;
402 * Check validity of response with a hostname for a DNS lookup.
405 * @param msg message with the hostname
408 check_response (void *cls,
409 const struct GNUNET_MessageHeader *msg)
411 /* implemented in #handle_response() for now */
417 * Check validity of response with a hostname for a DNS lookup.
418 * NOTE: right now rather messy, might want to use different
419 * message types for different response formats in the future.
422 * @param msg message with the response
425 handle_response (void *cls,
426 const struct GNUNET_MessageHeader *msg)
428 struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
432 size = ntohs (msg->size);
433 if (size == sizeof (struct GNUNET_MessageHeader))
435 LOG (GNUNET_ERROR_TYPE_DEBUG,
436 "Received empty response from DNS service\n");
437 /* message contains not data, just header; end of replies */
438 /* check if request was canceled */
439 if (GNUNET_SYSERR != rh->was_transmitted)
441 /* no reverse lookup was successful, return IP as string */
442 if (NULL != rh->name_callback)
444 if (GNUNET_NO == rh->received_response)
446 nret = no_resolve (rh->af,
449 rh->name_callback (rh->cls, nret);
452 /* finally, make termination call */
453 rh->name_callback (rh->cls,
456 if (NULL != rh->addr_callback)
457 rh->addr_callback (rh->cls,
461 rh->was_transmitted = GNUNET_NO;
462 GNUNET_RESOLVER_request_cancel (rh);
466 /* return reverse lookup results to caller */
467 if (NULL != rh->name_callback)
469 const char *hostname;
471 hostname = (const char *) &msg[1];
472 if (hostname[size - sizeof (struct GNUNET_MessageHeader) - 1] != '\0')
475 if (GNUNET_SYSERR != rh->was_transmitted)
476 rh->name_callback (rh->cls,
478 rh->was_transmitted = GNUNET_NO;
479 GNUNET_RESOLVER_request_cancel (rh);
480 GNUNET_MQ_destroy (mq);
485 LOG (GNUNET_ERROR_TYPE_DEBUG,
486 "Resolver returns `%s' for IP `%s'.\n",
488 GNUNET_a2s ((const void *) &rh[1],
490 if (rh->was_transmitted != GNUNET_SYSERR)
491 rh->name_callback (rh->cls,
493 rh->received_response = GNUNET_YES;
495 /* return lookup results to caller */
496 if (NULL != rh->addr_callback)
498 struct sockaddr_in v4;
499 struct sockaddr_in6 v6;
500 const struct sockaddr *sa;
506 ip_len = size - sizeof (struct GNUNET_MessageHeader);
507 if (ip_len == sizeof (struct in_addr))
509 memset (&v4, 0, sizeof (v4));
510 v4.sin_family = AF_INET;
511 v4.sin_addr = *(struct in_addr*) ip;
512 #if HAVE_SOCKADDR_IN_SIN_LEN
513 v4.sin_len = sizeof (v4);
516 sa = (const struct sockaddr *) &v4;
518 else if (ip_len == sizeof (struct in6_addr))
520 memset (&v6, 0, sizeof (v6));
521 v6.sin6_family = AF_INET6;
522 v6.sin6_addr = *(struct in6_addr*) ip;
523 #if HAVE_SOCKADDR_IN_SIN_LEN
524 v6.sin6_len = sizeof (v6);
527 sa = (const struct sockaddr *) &v6;
532 if (GNUNET_SYSERR != rh->was_transmitted)
533 rh->addr_callback (rh->cls,
536 rh->was_transmitted = GNUNET_NO;
537 GNUNET_RESOLVER_request_cancel (rh);
538 GNUNET_MQ_destroy (mq);
543 LOG (GNUNET_ERROR_TYPE_DEBUG,
544 "Received IP from DNS service\n");
545 if (GNUNET_SYSERR != rh->was_transmitted)
546 rh->addr_callback (rh->cls,
554 * We've been asked to lookup the address for a hostname and were
555 * given a valid numeric string. Perform the callbacks for the
558 * @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
561 numeric_resolution (void *cls)
563 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
564 struct sockaddr_in v4;
565 struct sockaddr_in6 v6;
566 const char *hostname;
569 memset (&v4, 0, sizeof (v4));
570 v4.sin_family = AF_INET;
571 #if HAVE_SOCKADDR_IN_SIN_LEN
572 v4.sin_len = sizeof (v4);
574 memset (&v6, 0, sizeof (v6));
575 v6.sin6_family = AF_INET6;
576 #if HAVE_SOCKADDR_IN_SIN_LEN
577 v6.sin6_len = sizeof (v6);
579 hostname = (const char *) &rh[1];
580 if (((rh->af == AF_UNSPEC) || (rh->af == AF_INET)) &&
581 (1 == inet_pton (AF_INET, hostname, &v4.sin_addr)))
583 rh->addr_callback (rh->cls,
584 (const struct sockaddr *) &v4,
586 if ((rh->af == AF_UNSPEC) &&
587 (1 == inet_pton (AF_INET6, hostname, &v6.sin6_addr)))
589 /* this can happen on some systems IF "hostname" is "localhost" */
590 rh->addr_callback (rh->cls,
591 (const struct sockaddr *) &v6,
594 rh->addr_callback (rh->cls,
600 if ( ( (rh->af == AF_UNSPEC) ||
601 (rh->af == AF_INET6) ) &&
602 (1 == inet_pton (AF_INET6, hostname, &v6.sin6_addr) ) )
604 rh->addr_callback (rh->cls,
605 (const struct sockaddr *) &v6,
607 rh->addr_callback (rh->cls,
613 /* why are we here? this task should not have been scheduled! */
620 * We've been asked to lookup the address for a hostname and were
621 * given a variant of "loopback". Perform the callbacks for the
622 * respective loopback numeric addresses.
624 * @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
627 loopback_resolution (void *cls)
629 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
630 struct sockaddr_in v4;
631 struct sockaddr_in6 v6;
634 memset (&v4, 0, sizeof (v4));
635 v4.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
636 v4.sin_family = AF_INET;
637 #if HAVE_SOCKADDR_IN_SIN_LEN
638 v4.sin_len = sizeof (v4);
640 memset (&v6, 0, sizeof (v6));
641 v6.sin6_family = AF_INET6;
642 #if HAVE_SOCKADDR_IN_SIN_LEN
643 v6.sin6_len = sizeof (v6);
645 v6.sin6_addr = in6addr_loopback;
649 rh->addr_callback (rh->cls,
650 (const struct sockaddr *) &v4,
654 rh->addr_callback (rh->cls,
655 (const struct sockaddr *) &v6,
659 rh->addr_callback (rh->cls,
660 (const struct sockaddr *) &v6,
662 rh->addr_callback (rh->cls,
663 (const struct sockaddr *) &v4,
671 rh->addr_callback (rh->cls,
679 * Now try to reconnect to the resolver service.
684 reconnect_task (void *cls)
686 GNUNET_MQ_hd_var_size (response,
687 GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE,
688 struct GNUNET_MessageHeader);
689 struct GNUNET_MQ_MessageHandler handlers[] = {
690 make_response_handler (NULL),
691 GNUNET_MQ_handler_end ()
695 if (NULL == req_head)
696 return; /* no work pending */
697 LOG (GNUNET_ERROR_TYPE_DEBUG,
698 "Trying to connect to DNS service\n");
699 mq = GNUNET_CLIENT_connecT (resolver_cfg,
706 LOG (GNUNET_ERROR_TYPE_DEBUG,
707 "Failed to connect, will try again later\n");
716 * Adjust exponential back-off and reconnect to the service.
721 struct GNUNET_RESOLVER_RequestHandle *rh;
725 GNUNET_assert (NULL == mq);
726 if (NULL != (rh = req_head))
728 switch (rh->was_transmitted)
731 /* nothing more to do */
734 /* disconnected, transmit again! */
735 rh->was_transmitted = GNUNET_NO;
738 /* request was cancelled, remove entirely */
739 GNUNET_CONTAINER_DLL_remove (req_head,
749 LOG (GNUNET_ERROR_TYPE_DEBUG,
750 "Will try to connect to DNS service in %s\n",
751 GNUNET_STRINGS_relative_time_to_string (backoff,
753 GNUNET_assert (NULL != resolver_cfg);
754 r_task = GNUNET_SCHEDULER_add_delayed (backoff,
757 backoff = GNUNET_TIME_STD_BACKOFF (backoff);
762 * A DNS resolution timed out. Notify the application.
764 * @param cls the `struct GNUNET_RESOLVER_RequestHandle *`
767 handle_lookup_timeout (void *cls)
769 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
772 if (GNUNET_NO == rh->direction)
774 LOG (GNUNET_ERROR_TYPE_INFO,
775 _("Timeout trying to resolve hostname `%s'.\n"),
776 (const char *) &rh[1]);
777 if (NULL != rh->addr_callback)
778 rh->addr_callback (rh->cls,
784 char buf[INET6_ADDRSTRLEN];
786 LOG (GNUNET_ERROR_TYPE_INFO,
787 _("Timeout trying to resolve IP address `%s'.\n"),
789 (const void *) &rh[1],
792 if (GNUNET_NO == rh->received_response)
796 nret = no_resolve (rh->af,
799 if (NULL != rh->name_callback)
800 rh->name_callback (rh->cls, nret);
803 /* finally, make termination call */
804 if (NULL != rh->name_callback)
805 rh->name_callback (rh->cls,
808 rh->was_transmitted = GNUNET_NO;
809 GNUNET_RESOLVER_request_cancel (rh);
815 * Convert a string to one or more IP addresses.
817 * @param hostname the hostname to resolve
818 * @param af AF_INET or AF_INET6; use AF_UNSPEC for "any"
819 * @param callback function to call with addresses
820 * @param callback_cls closure for @a callback
821 * @param timeout how long to try resolving
822 * @return handle that can be used to cancel the request, NULL on error
824 struct GNUNET_RESOLVER_RequestHandle *
825 GNUNET_RESOLVER_ip_get (const char *hostname,
827 struct GNUNET_TIME_Relative timeout,
828 GNUNET_RESOLVER_AddressCallback callback,
831 struct GNUNET_RESOLVER_RequestHandle *rh;
837 slen = strlen (hostname) + 1;
838 if (slen + sizeof (struct GNUNET_RESOLVER_GetMessage) >=
839 GNUNET_SERVER_MAX_MESSAGE_SIZE)
844 rh = GNUNET_malloc (sizeof (struct GNUNET_RESOLVER_RequestHandle) + slen);
846 rh->addr_callback = callback;
847 rh->cls = callback_cls;
852 rh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
853 rh->direction = GNUNET_NO;
854 /* first, check if this is a numeric address */
855 if (((1 == inet_pton (AF_INET, hostname, &v4)) &&
856 ((af == AF_INET) || (af == AF_UNSPEC))) ||
857 ((1 == inet_pton (AF_INET6, hostname, &v6)) &&
858 ((af == AF_INET6) || (af == AF_UNSPEC))))
860 rh->task = GNUNET_SCHEDULER_add_now (&numeric_resolution,
864 /* then, check if this is a loopback address */
866 while (NULL != loopback[i])
867 if (0 == strcasecmp (loopback[i++],
870 rh->task = GNUNET_SCHEDULER_add_now (&loopback_resolution,
874 if (GNUNET_OK != check_config ())
879 rh->task = GNUNET_SCHEDULER_add_delayed (timeout,
880 &handle_lookup_timeout,
882 GNUNET_CONTAINER_DLL_insert_tail (req_head,
885 rh->was_queued = GNUNET_YES;
888 GNUNET_SCHEDULER_cancel (s_task);
897 * We've been asked to convert an address to a string without
898 * a reverse lookup, either because the client asked for it
899 * or because the DNS lookup hit a timeout. Do the numeric
900 * conversion and invoke the callback.
902 * @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
905 numeric_reverse (void *cls)
907 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
911 result = no_resolve (rh->af,
914 LOG (GNUNET_ERROR_TYPE_DEBUG,
915 "Resolver returns `%s'.\n",
919 rh->name_callback (rh->cls,
921 GNUNET_free (result);
923 rh->name_callback (rh->cls,
925 if (NULL != rh->task)
927 GNUNET_SCHEDULER_cancel (rh->task);
935 * Get an IP address as a string.
937 * @param sa host address
938 * @param salen length of host address in @a sa
939 * @param do_resolve use #GNUNET_NO to return numeric hostname
940 * @param timeout how long to try resolving
941 * @param callback function to call with hostnames
942 * last callback is NULL when finished
943 * @param cls closure for @a callback
944 * @return handle that can be used to cancel the request
946 struct GNUNET_RESOLVER_RequestHandle *
947 GNUNET_RESOLVER_hostname_get (const struct sockaddr *sa,
950 struct GNUNET_TIME_Relative timeout,
951 GNUNET_RESOLVER_HostnameCallback callback,
954 struct GNUNET_RESOLVER_RequestHandle *rh;
958 if (GNUNET_OK != check_config ())
960 LOG (GNUNET_ERROR_TYPE_ERROR,
961 _("Resolver not configured correctly.\n"));
965 switch (sa->sa_family)
968 GNUNET_assert (salen == sizeof (struct sockaddr_in));
969 ip_len = sizeof (struct in_addr);
970 ip = &((const struct sockaddr_in*)sa)->sin_addr;
973 GNUNET_assert (salen == sizeof (struct sockaddr_in6));
974 ip_len = sizeof (struct in6_addr);
975 ip = &((const struct sockaddr_in6*)sa)->sin6_addr;
981 rh = GNUNET_malloc (sizeof (struct GNUNET_RESOLVER_RequestHandle) + salen);
982 rh->name_callback = callback;
984 rh->af = sa->sa_family;
985 rh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
989 rh->data_len = ip_len;
990 rh->direction = GNUNET_YES;
991 rh->received_response = GNUNET_NO;
992 if (GNUNET_NO == do_resolve)
994 rh->task = GNUNET_SCHEDULER_add_now (&numeric_reverse,
998 rh->task = GNUNET_SCHEDULER_add_delayed (timeout,
999 &handle_lookup_timeout,
1001 GNUNET_CONTAINER_DLL_insert_tail (req_head,
1004 rh->was_queued = GNUNET_YES;
1007 GNUNET_SCHEDULER_cancel (s_task);
1010 process_requests ();
1016 * Get local fully qualified af name
1021 GNUNET_RESOLVER_local_fqdn_get ()
1023 char hostname[GNUNET_OS_get_hostname_max_length () + 1];
1025 if (0 != gethostname (hostname, sizeof (hostname) - 1))
1027 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
1031 LOG (GNUNET_ERROR_TYPE_DEBUG,
1032 "Resolving our FQDN `%s'\n",
1034 #if HAVE_GETADDRINFO
1036 struct addrinfo *ai;
1040 if (0 != (ret = getaddrinfo (hostname, NULL, NULL, &ai)))
1042 LOG (GNUNET_ERROR_TYPE_ERROR,
1043 _("Could not resolve our FQDN: %s\n"),
1044 gai_strerror (ret));
1047 if (NULL != ai->ai_canonname)
1048 rval = GNUNET_strdup (ai->ai_canonname);
1050 rval = GNUNET_strdup (hostname);
1054 #elif HAVE_GETHOSTBYNAME2
1056 struct hostent *host;
1058 host = gethostbyname2 (hostname, AF_INET);
1060 host = gethostbyname2 (hostname, AF_INET6);
1063 LOG (GNUNET_ERROR_TYPE_ERROR,
1064 _("Could not resolve our FQDN: %s\n"),
1065 hstrerror (h_errno));
1068 return GNUNET_strdup (host->h_name);
1070 #elif HAVE_GETHOSTBYNAME
1072 struct hostent *host;
1074 host = gethostbyname (hostname);
1077 LOG (GNUNET_ERROR_TYPE_ERROR,
1078 _("Could not resolve our FQDN: %s\n"),
1079 hstrerror (h_errno));
1082 return GNUNET_strdup (host->h_name);
1085 /* fallback: just hope name is already FQDN */
1086 return GNUNET_strdup (hostname);
1092 * Looking our own hostname.
1094 * @param af AF_INET or AF_INET6; use AF_UNSPEC for "any"
1095 * @param timeout how long to try resolving
1096 * @param callback function to call with addresses
1097 * @param cls closure for @a callback
1098 * @return handle that can be used to cancel the request, NULL on error
1100 struct GNUNET_RESOLVER_RequestHandle *
1101 GNUNET_RESOLVER_hostname_resolve (int af,
1102 struct GNUNET_TIME_Relative timeout,
1103 GNUNET_RESOLVER_AddressCallback callback,
1106 char hostname[GNUNET_OS_get_hostname_max_length () + 1];
1108 if (0 != gethostname (hostname, sizeof (hostname) - 1))
1110 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
1114 LOG (GNUNET_ERROR_TYPE_DEBUG,
1115 "Resolving our hostname `%s'\n",
1117 return GNUNET_RESOLVER_ip_get (hostname,
1126 * Cancel a request that is still pending with the resolver.
1127 * Note that a client MUST NOT cancel a request that has
1128 * been completed (i.e, the callback has been called to
1129 * signal timeout or the final result).
1131 * @param rh handle of request to cancel
1134 GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *rh)
1136 if (NULL != rh->task)
1138 GNUNET_SCHEDULER_cancel (rh->task);
1141 if (GNUNET_NO == rh->was_transmitted)
1143 if (GNUNET_YES == rh->was_queued)
1144 GNUNET_CONTAINER_DLL_remove (req_head,
1150 GNUNET_assert (GNUNET_YES == rh->was_transmitted);
1151 rh->was_transmitted = GNUNET_SYSERR; /* mark as cancelled */
1155 /* end of resolver_api.c */