2 This file is part of GNUnet.
3 (C) 2009 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 2, 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 library for building GNUnet network servers
24 * @author Christian Grothoff
28 #include "gnunet_common.h"
29 #include "gnunet_connection_lib.h"
30 #include "gnunet_scheduler_lib.h"
31 #include "gnunet_server_lib.h"
32 #include "gnunet_time_lib.h"
33 #include "gnunet_disk_lib.h"
34 #include "gnunet_protocols.h"
36 #define DEBUG_SERVER GNUNET_YES
39 * List of arrays of message handlers.
44 * This is a linked list.
46 struct HandlerList *next;
49 * NULL-terminated array of handlers.
51 const struct GNUNET_SERVER_MessageHandler *handlers;
56 * List of arrays of message handlers.
61 * This is a linked list.
63 struct NotifyList *next;
68 GNUNET_SERVER_DisconnectCallback callback;
71 * Closure for callback.
78 * @brief handle for a server
80 struct GNUNET_SERVER_Handle
85 struct GNUNET_SCHEDULER_Handle *sched;
88 * List of handlers for incoming messages.
90 struct HandlerList *handlers;
93 * List of our current clients.
95 struct GNUNET_SERVER_Client *clients;
98 * Linked list of functions to call on disconnects by clients.
100 struct NotifyList *disconnect_notify_list;
103 * Function to call for access control.
105 GNUNET_CONNECTION_AccessCheck access;
108 * Closure for access.
113 * NULL-terminated array of sockets used to listen for new
116 struct GNUNET_NETWORK_Handle **listen_sockets;
119 * After how long should an idle connection time
122 struct GNUNET_TIME_Relative idle_timeout;
125 * maximum write buffer size for accepted sockets
130 * Task scheduled to do the listening.
132 GNUNET_SCHEDULER_TaskIdentifier listen_task;
135 * Do we ignore messages of types that we do not understand or do we
136 * require that a handler is found (and if not kill the connection)?
141 * Should all of the clients of this server continue to process
142 * connections as usual even if we get a shutdown request? (the
143 * listen socket always ignores shutdown).
145 int clients_ignore_shutdown;
151 * @brief handle for a client of the server
153 struct GNUNET_SERVER_Client
157 * This is a linked list.
159 struct GNUNET_SERVER_Client *next;
162 * Processing of incoming data.
164 struct GNUNET_SERVER_MessageStreamTokenizer *mst;
167 * Server that this client belongs to.
169 struct GNUNET_SERVER_Handle *server;
172 * Client closure for callbacks.
174 struct GNUNET_CONNECTION_Handle *connection;
177 * ID of task used to restart processing.
179 GNUNET_SCHEDULER_TaskIdentifier restart_task;
182 * Last activity on this socket (used to time it out
183 * if reference_count == 0).
185 struct GNUNET_TIME_Absolute last_activity;
188 * Number of external entities with a reference to
189 * this client object.
191 unsigned int reference_count;
194 * Was processing if incoming messages suspended while
195 * we were still processing data already received?
196 * This is a counter saying how often processing was
197 * suspended (once per handler invoked).
199 unsigned int suspended;
202 * Are we currently in the "process_client_buffer" function (and
203 * will hence restart the receive job on exit if suspended == 0 once
204 * we are done?). If this is set, then "receive_done" will
205 * essentially only decrement suspended; if this is not set, then
206 * "receive_done" may need to restart the receive process (either
207 * from the side-buffer or via select/recv).
209 int in_process_client_buffer;
212 * We're about to close down this client due to some serious
218 * Are we currently trying to receive? (YES if we are, NO if we are not,
219 * SYSERR if data is already available in MST).
224 * Persist the file handle for this client no matter what happens,
225 * force the OS to close once the process actually dies. Should only
226 * be used in special cases!
233 * Scheduler says our listen socket is ready. Process it!
235 * @param cls handle to our server for which we are processing the listen
237 * @param tc reason why we are running right now
240 process_listen_socket (void *cls,
241 const struct GNUNET_SCHEDULER_TaskContext *tc)
243 struct GNUNET_SERVER_Handle *server = cls;
244 struct GNUNET_CONNECTION_Handle *sock;
245 struct GNUNET_SERVER_Client *client;
246 struct GNUNET_NETWORK_FDSet *r;
249 server->listen_task = GNUNET_SCHEDULER_NO_TASK;
250 r = GNUNET_NETWORK_fdset_create ();
252 while (NULL != server->listen_sockets[i])
253 GNUNET_NETWORK_fdset_set (r, server->listen_sockets[i++]);
254 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
256 /* ignore shutdown, someone else will take care of it! */
257 server->listen_task = GNUNET_SCHEDULER_add_select (server->sched,
258 GNUNET_SCHEDULER_PRIORITY_HIGH,
259 GNUNET_SCHEDULER_NO_TASK,
260 GNUNET_TIME_UNIT_FOREVER_REL,
262 &process_listen_socket,
264 GNUNET_NETWORK_fdset_destroy (r);
268 while (NULL != server->listen_sockets[i])
270 if (GNUNET_NETWORK_fdset_isset
271 (tc->read_ready, server->listen_sockets[i]))
274 GNUNET_CONNECTION_create_from_accept (tc->sched, server->access,
276 server->listen_sockets[i],
281 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
282 "Server accepted incoming connection.\n");
284 client = GNUNET_SERVER_connect_socket (server, sock);
285 GNUNET_CONNECTION_ignore_shutdown (sock,
286 server->clients_ignore_shutdown);
287 /* decrement reference count, we don't keep "client" alive */
288 GNUNET_SERVER_client_drop (client);
293 /* listen for more! */
294 server->listen_task = GNUNET_SCHEDULER_add_select (server->sched,
295 GNUNET_SCHEDULER_PRIORITY_HIGH,
296 GNUNET_SCHEDULER_NO_TASK,
297 GNUNET_TIME_UNIT_FOREVER_REL,
299 &process_listen_socket,
301 GNUNET_NETWORK_fdset_destroy (r);
306 * Create and initialize a listen socket for the server.
308 * @param serverAddr address to listen on
309 * @param socklen length of address
310 * @return NULL on error, otherwise the listen socket
312 static struct GNUNET_NETWORK_Handle *
313 open_listen_socket (const struct sockaddr *serverAddr, socklen_t socklen)
315 const static int on = 1;
316 struct GNUNET_NETWORK_Handle *sock;
320 switch (serverAddr->sa_family)
323 port = ntohs (((const struct sockaddr_in *) serverAddr)->sin_port);
326 port = ntohs (((const struct sockaddr_in6 *) serverAddr)->sin6_port);
332 sock = GNUNET_NETWORK_socket_create (serverAddr->sa_family, SOCK_STREAM, 0);
335 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "socket");
341 if (GNUNET_NETWORK_socket_setsockopt
342 (sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof (on)) != GNUNET_OK)
343 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
346 if ( (serverAddr->sa_family == AF_INET6) &&
347 (GNUNET_NETWORK_socket_setsockopt
348 (sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof (on)) != GNUNET_OK) )
349 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
353 /* bind the socket */
354 if (GNUNET_NETWORK_socket_bind (sock, serverAddr, socklen) != GNUNET_OK)
357 if (errno != EADDRINUSE)
359 /* we don't log 'EADDRINUSE' here since an IPv4 bind may
360 fail if we already took the port on IPv6; if both IPv4 and
361 IPv6 binds fail, then our caller will log using the
362 errno preserved in 'eno' */
363 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
365 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
367 ("`%s' failed for port %d (%s).\n"),
369 (serverAddr->sa_family == AF_INET) ? "IPv4" : "IPv6");
372 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
376 if (GNUNET_OK != GNUNET_NETWORK_socket_listen (sock, 5))
378 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "listen");
379 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
385 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
386 "Server starts to listen on port %u.\n", port);
393 * Create a new server.
395 * @param sched scheduler to use
396 * @param access function for access control
397 * @param access_cls closure for access
398 * @param lsocks NULL-terminated array of listen sockets
399 * @param maxbuf maximum write buffer size for accepted sockets
400 * @param idle_timeout after how long should we timeout idle connections?
401 * @param require_found if YES, connections sending messages of unknown type
403 * @return handle for the new server, NULL on error
404 * (typically, "port" already in use)
406 struct GNUNET_SERVER_Handle *
407 GNUNET_SERVER_create_with_sockets (struct GNUNET_SCHEDULER_Handle *sched,
408 GNUNET_CONNECTION_AccessCheck access, void *access_cls,
409 struct GNUNET_NETWORK_Handle **lsocks,
411 struct GNUNET_TIME_Relative
415 struct GNUNET_SERVER_Handle *ret;
416 struct GNUNET_NETWORK_FDSet *r;
419 ret = GNUNET_malloc (sizeof (struct GNUNET_SERVER_Handle));
421 ret->maxbuf = maxbuf;
422 ret->idle_timeout = idle_timeout;
423 ret->listen_sockets = lsocks;
424 ret->access = access;
425 ret->access_cls = access_cls;
426 ret->require_found = require_found;
429 r = GNUNET_NETWORK_fdset_create ();
431 while (NULL != ret->listen_sockets[i])
432 GNUNET_NETWORK_fdset_set (r, ret->listen_sockets[i++]);
433 ret->listen_task = GNUNET_SCHEDULER_add_select (sched,
434 GNUNET_SCHEDULER_PRIORITY_HIGH,
435 GNUNET_SCHEDULER_NO_TASK,
436 GNUNET_TIME_UNIT_FOREVER_REL,
438 &process_listen_socket,
440 GNUNET_NETWORK_fdset_destroy (r);
447 * Create a new server.
449 * @param sched scheduler to use
450 * @param access function for access control
451 * @param access_cls closure for access
452 * @param serverAddr address to listen on (including port), NULL terminated array
453 * @param socklen length of serverAddr
454 * @param maxbuf maximum write buffer size for accepted sockets
455 * @param idle_timeout after how long should we timeout idle connections?
456 * @param require_found if YES, connections sending messages of unknown type
458 * @return handle for the new server, NULL on error
459 * (typically, "port" already in use)
461 struct GNUNET_SERVER_Handle *
462 GNUNET_SERVER_create (struct GNUNET_SCHEDULER_Handle *sched,
463 GNUNET_CONNECTION_AccessCheck access,
465 struct sockaddr *const *serverAddr,
466 const socklen_t * socklen,
468 struct GNUNET_TIME_Relative
469 idle_timeout, int require_found)
471 struct GNUNET_NETWORK_Handle **lsocks;
476 while (serverAddr[i] != NULL)
481 GNUNET_malloc (sizeof (struct GNUNET_NETWORK_Handle *) * (i + 1));
484 while (serverAddr[i] != NULL)
486 lsocks[j] = open_listen_socket (serverAddr[i], socklen[i]);
487 if (lsocks[j] != NULL)
494 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
495 GNUNET_free (lsocks);
503 return GNUNET_SERVER_create_with_sockets (sched,
513 * Free resources held by this server.
515 * @param s server to destroy
518 GNUNET_SERVER_destroy (struct GNUNET_SERVER_Handle *s)
520 struct HandlerList *hpos;
521 struct NotifyList *npos;
525 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Server shutting down.\n");
527 if (GNUNET_SCHEDULER_NO_TASK != s->listen_task)
529 GNUNET_SCHEDULER_cancel (s->sched, s->listen_task);
530 s->listen_task = GNUNET_SCHEDULER_NO_TASK;
532 if (s->listen_sockets != NULL)
535 while (s->listen_sockets[i] != NULL)
536 GNUNET_break (GNUNET_OK ==
537 GNUNET_NETWORK_socket_close (s->listen_sockets[i++]));
538 GNUNET_free (s->listen_sockets);
539 s->listen_sockets = NULL;
541 while (s->clients != NULL)
542 GNUNET_SERVER_client_disconnect (s->clients);
543 while (NULL != (hpos = s->handlers))
545 s->handlers = hpos->next;
548 while (NULL != (npos = s->disconnect_notify_list))
550 npos->callback (npos->callback_cls, NULL);
551 s->disconnect_notify_list = npos->next;
559 * Add additional handlers to an existing server.
561 * @param server the server to add handlers to
562 * @param handlers array of message handlers for
563 * incoming messages; the last entry must
564 * have "NULL" for the "callback"; multiple
565 * entries for the same type are allowed,
566 * they will be called in order of occurence.
567 * These handlers can be removed later;
568 * the handlers array must exist until removed
569 * (or server is destroyed).
572 GNUNET_SERVER_add_handlers (struct GNUNET_SERVER_Handle *server,
573 const struct GNUNET_SERVER_MessageHandler
576 struct HandlerList *p;
578 p = GNUNET_malloc (sizeof (struct HandlerList));
579 p->handlers = handlers;
580 p->next = server->handlers;
581 server->handlers = p;
586 * Inject a message into the server, pretend it came
587 * from the specified client. Delivery of the message
588 * will happen instantly (if a handler is installed;
589 * otherwise the call does nothing).
591 * @param server the server receiving the message
592 * @param sender the "pretended" sender of the message
594 * @param message message to transmit
595 * @return GNUNET_OK if the message was OK and the
596 * connection can stay open
597 * GNUNET_SYSERR if the connection to the
598 * client should be shut down
601 GNUNET_SERVER_inject (struct GNUNET_SERVER_Handle *server,
602 struct GNUNET_SERVER_Client *sender,
603 const struct GNUNET_MessageHeader *message)
605 struct HandlerList *pos;
606 const struct GNUNET_SERVER_MessageHandler *mh;
612 type = ntohs (message->type);
613 size = ntohs (message->size);
615 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
616 "Server schedules transmission of %u-byte message of type %u to client.\n",
619 pos = server->handlers;
624 while (pos->handlers[i].callback != NULL)
626 mh = &pos->handlers[i];
627 if ( (mh->type == type) ||
628 (mh->type == GNUNET_MESSAGE_TYPE_ALL) )
630 if ((mh->expected_size != 0) && (mh->expected_size != size))
633 return GNUNET_SYSERR;
637 mh->callback (mh->callback_cls, sender, message);
644 if (found == GNUNET_NO)
646 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
647 "Received message of unknown type %d\n",
649 if (server->require_found == GNUNET_YES)
650 return GNUNET_SYSERR;
657 * We are receiving an incoming message. Process it.
659 * @param cls our closure (handle for the client)
660 * @param buf buffer with data received from network
661 * @param available number of bytes available in buf
662 * @param addr address of the sender
663 * @param addrlen length of addr
664 * @param errCode code indicating errors receiving, 0 for success
667 process_incoming (void *cls,
670 const struct sockaddr *addr,
671 socklen_t addrlen, int errCode);
675 * Process messages from the client's message tokenizer until either
676 * the tokenizer is empty (and then schedule receiving more), or
677 * until some handler is not immediately done (then wait for restart_processing)
680 * @param client the client to process, RC must have already been increased
681 * using GNUNET_SERVER_client_keep and will be decreased by one in this
683 * @param ret GNUNET_NO to start processing from the buffer,
684 * GNUNET_OK if the mst buffer is drained and we should instantly go back to receiving
685 * GNUNET_SYSERR if we should instantly abort due to error in a previous step
688 process_mst (struct GNUNET_SERVER_Client *client,
691 while ( (ret != GNUNET_SYSERR) &&
692 (client->server != NULL) &&
693 (GNUNET_YES != client->shutdown_now) &&
694 (0 == client->suspended) )
696 if (ret == GNUNET_OK)
698 client->receive_pending = GNUNET_YES;
700 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
701 "Server re-enters receive loop.\n");
703 GNUNET_CONNECTION_receive (client->connection,
704 GNUNET_SERVER_MAX_MESSAGE_SIZE,
705 client->server->idle_timeout,
706 &process_incoming, client);
710 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Server processes additional messages instantly.\n");
712 ret = GNUNET_SERVER_mst_receive (client->mst, client, NULL, 0, GNUNET_NO, GNUNET_YES);
715 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
716 "Server leaves instant processing loop: ret = %d, server = %p, shutdown = %d, suspended = %u\n",
719 client->shutdown_now,
723 if (ret == GNUNET_NO)
726 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
727 "Server has more data pending but is suspended.\n");
729 client->receive_pending = GNUNET_SYSERR; /* data pending */
731 if ( (ret == GNUNET_SYSERR) ||
732 (GNUNET_YES == client->shutdown_now) )
733 GNUNET_SERVER_client_disconnect (client);
734 GNUNET_SERVER_client_drop (client);
739 * We are receiving an incoming message. Process it.
741 * @param cls our closure (handle for the client)
742 * @param buf buffer with data received from network
743 * @param available number of bytes available in buf
744 * @param addr address of the sender
745 * @param addrlen length of addr
746 * @param errCode code indicating errors receiving, 0 for success
749 process_incoming (void *cls,
752 const struct sockaddr *addr,
753 socklen_t addrlen, int errCode)
755 struct GNUNET_SERVER_Client *client = cls;
756 struct GNUNET_SERVER_Handle *server = client->server;
759 GNUNET_assert (client->receive_pending == GNUNET_YES);
760 client->receive_pending = GNUNET_NO;
765 (client->shutdown_now == GNUNET_YES) ||
766 (GNUNET_YES != GNUNET_CONNECTION_check (client->connection)))
768 /* other side closed connection, error connecting, etc. */
769 GNUNET_SERVER_client_disconnect (client);
773 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
774 "Server receives %u bytes from `%s'.\n",
775 (unsigned int) available,
776 GNUNET_a2s (addr, addrlen));
778 GNUNET_SERVER_client_keep (client);
779 client->last_activity = GNUNET_TIME_absolute_get ();
780 ret = GNUNET_SERVER_mst_receive (client->mst, client, buf, available, GNUNET_NO, GNUNET_YES);
781 process_mst (client, ret);
786 * Task run to start again receiving from the network
787 * and process requests.
789 * @param cls our 'struct GNUNET_SERVER_Client*' to process more requests from
790 * @param tc scheduler context (unused)
793 restart_processing (void *cls,
794 const struct GNUNET_SCHEDULER_TaskContext *tc)
796 struct GNUNET_SERVER_Client *client = cls;
797 struct GNUNET_SERVER_Handle *server = client->server;
799 client->restart_task = GNUNET_SCHEDULER_NO_TASK;
800 if ( (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) &&
801 (GNUNET_NO == server->clients_ignore_shutdown) )
803 GNUNET_SERVER_client_disconnect (client);
806 if (client->receive_pending == GNUNET_NO)
809 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
810 "Server begins to read again from client.\n");
812 client->receive_pending = GNUNET_YES;
813 GNUNET_CONNECTION_receive (client->connection,
814 GNUNET_SERVER_MAX_MESSAGE_SIZE,
815 client->server->idle_timeout, &process_incoming, client);
819 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
820 "Server continues processing messages still in the buffer.\n");
822 GNUNET_SERVER_client_keep (client);
823 client->receive_pending = GNUNET_NO;
824 process_mst (client, GNUNET_NO);
829 * This function is called whenever our inbound message tokenizer has
830 * received a complete message.
832 * @param cls closure (struct GNUNET_SERVER_Handle)
833 * @param client identification of the client (struct GNUNET_SERVER_Client*)
834 * @param message the actual message
837 client_message_tokenizer_callback (void *cls,
839 const struct GNUNET_MessageHeader *message)
841 struct GNUNET_SERVER_Handle *server = cls;
842 struct GNUNET_SERVER_Client *sender = client;
846 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
847 "Tokenizer gives server message of type %u from client\n",
848 ntohs (message->type));
850 sender->in_process_client_buffer = GNUNET_YES;
851 ret = GNUNET_SERVER_inject (server, sender, message);
852 sender->in_process_client_buffer = GNUNET_NO;
853 if (GNUNET_OK != ret)
854 GNUNET_SERVER_client_disconnect (sender);
859 * Add a TCP socket-based connection to the set of handles managed by
860 * this server. Use this function for outgoing (P2P) connections that
861 * we initiated (and where this server should process incoming
864 * @param server the server to use
865 * @param connection the connection to manage (client must
866 * stop using this connection from now on)
867 * @return the client handle (client should call
868 * "client_drop" on the return value eventually)
870 struct GNUNET_SERVER_Client *
871 GNUNET_SERVER_connect_socket (struct
874 struct GNUNET_CONNECTION_Handle *connection)
876 struct GNUNET_SERVER_Client *client;
878 client = GNUNET_malloc (sizeof (struct GNUNET_SERVER_Client));
879 client->connection = connection;
880 client->mst = GNUNET_SERVER_mst_create (GNUNET_SERVER_MAX_MESSAGE_SIZE,
881 &client_message_tokenizer_callback,
883 client->reference_count = 1;
884 client->server = server;
885 client->last_activity = GNUNET_TIME_absolute_get ();
886 client->next = server->clients;
887 server->clients = client;
888 client->receive_pending = GNUNET_YES;
889 GNUNET_CONNECTION_receive (client->connection,
890 GNUNET_SERVER_MAX_MESSAGE_SIZE,
891 server->idle_timeout, &process_incoming, client);
897 * Notify the server that the given client handle should
898 * be kept (keeps the connection up if possible, increments
899 * the internal reference counter).
901 * @param client the client to keep
904 GNUNET_SERVER_client_keep (struct GNUNET_SERVER_Client *client)
906 client->reference_count++;
911 * Notify the server that the given client handle is no
912 * longer required. Decrements the reference counter. If
913 * that counter reaches zero an inactive connection maybe
916 * @param client the client to drop
919 GNUNET_SERVER_client_drop (struct GNUNET_SERVER_Client *client)
921 GNUNET_assert (client->reference_count > 0);
922 client->reference_count--;
923 if ( (client->shutdown_now == GNUNET_YES) &&
924 (client->reference_count == 0) )
925 GNUNET_SERVER_client_disconnect (client);
930 * Obtain the network address of the other party.
932 * @param client the client to get the address for
933 * @param addr where to store the address
934 * @param addrlen where to store the length of the address
935 * @return GNUNET_OK on success
938 GNUNET_SERVER_client_get_address (struct GNUNET_SERVER_Client *client,
939 void **addr, size_t * addrlen)
941 return GNUNET_CONNECTION_get_address (client->connection,
947 * Ask the server to notify us whenever a client disconnects.
948 * This function is called whenever the actual network connection
949 * is closed; the reference count may be zero or larger than zero
952 * @param server the server manageing the clients
953 * @param callback function to call on disconnect
954 * @param callback_cls closure for callback
957 GNUNET_SERVER_disconnect_notify (struct GNUNET_SERVER_Handle *server,
958 GNUNET_SERVER_DisconnectCallback callback,
961 struct NotifyList *n;
963 n = GNUNET_malloc (sizeof (struct NotifyList));
964 n->callback = callback;
965 n->callback_cls = callback_cls;
966 n->next = server->disconnect_notify_list;
967 server->disconnect_notify_list = n;
972 * Ask the server to stop notifying us whenever a client disconnects.
974 * @param server the server manageing the clients
975 * @param callback function to call on disconnect
976 * @param callback_cls closure for callback
979 GNUNET_SERVER_disconnect_notify_cancel (struct GNUNET_SERVER_Handle *server,
980 GNUNET_SERVER_DisconnectCallback callback,
983 struct NotifyList *pos;
984 struct NotifyList *prev;
987 pos = server->disconnect_notify_list;
990 if ( (pos->callback == callback) &&
991 (pos->callback_cls == callback_cls ) )
1002 server->disconnect_notify_list = pos->next;
1004 prev->next = pos->next;
1010 * Ask the server to disconnect from the given client.
1011 * This is the same as returning GNUNET_SYSERR from a message
1012 * handler, except that it allows dropping of a client even
1013 * when not handling a message from that client.
1015 * @param client the client to disconnect from
1018 GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client)
1020 struct GNUNET_SERVER_Client *prev;
1021 struct GNUNET_SERVER_Client *pos;
1022 struct GNUNET_SERVER_Handle *server;
1023 struct NotifyList *n;
1027 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1028 "Client is being disconnected from the server.\n");
1030 if (client->restart_task != GNUNET_SCHEDULER_NO_TASK)
1032 GNUNET_SCHEDULER_cancel (client->server->sched,
1033 client->restart_task);
1034 client->restart_task = GNUNET_SCHEDULER_NO_TASK;
1036 if (GNUNET_YES == client->receive_pending)
1038 GNUNET_CONNECTION_receive_cancel (client->connection);
1039 client->receive_pending = GNUNET_NO;
1042 rc = client->reference_count;
1043 if (client->server != NULL)
1045 server = client->server;
1046 client->server = NULL;
1047 client->shutdown_now = GNUNET_YES;
1049 pos = server->clients;
1050 while ((pos != NULL) && (pos != client))
1055 GNUNET_assert (pos != NULL);
1057 server->clients = pos->next;
1059 prev->next = pos->next;
1060 if (client->restart_task != GNUNET_SCHEDULER_NO_TASK)
1062 GNUNET_SCHEDULER_cancel (server->sched,
1063 client->restart_task);
1064 client->restart_task = GNUNET_SCHEDULER_NO_TASK;
1066 n = server->disconnect_notify_list;
1069 n->callback (n->callback_cls, client);
1076 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1077 "RC still positive, not destroying everything.\n");
1081 if (client->in_process_client_buffer == GNUNET_YES)
1084 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1085 "Still processing inputs, not destroying everything.\n");
1090 if (client->persist == GNUNET_YES)
1091 GNUNET_CONNECTION_persist_ (client->connection);
1092 GNUNET_CONNECTION_destroy (client->connection, GNUNET_NO);
1093 GNUNET_SERVER_mst_destroy (client->mst);
1094 GNUNET_free (client);
1099 * Notify us when the server has enough space to transmit
1100 * a message of the given size to the given client.
1102 * @param client client to transmit message to
1103 * @param size requested amount of buffer space
1104 * @param timeout after how long should we give up (and call
1105 * notify with buf NULL and size 0)?
1106 * @param callback function to call when space is available
1107 * @param callback_cls closure for callback
1108 * @return non-NULL if the notify callback was queued; can be used
1109 * to cancel the request using
1110 * GNUNET_CONNECTION_notify_transmit_ready_cancel.
1111 * NULL if we are already going to notify someone else (busy)
1113 struct GNUNET_CONNECTION_TransmitHandle *
1114 GNUNET_SERVER_notify_transmit_ready (struct GNUNET_SERVER_Client *client,
1116 struct GNUNET_TIME_Relative timeout,
1117 GNUNET_CONNECTION_TransmitReadyNotify
1118 callback, void *callback_cls)
1120 return GNUNET_CONNECTION_notify_transmit_ready (client->connection,
1122 timeout, callback, callback_cls);
1126 * Set the persistent flag on this client, used to setup client connection
1127 * to only be killed when the service it's connected to is actually dead.
1129 * @param client the client to set the persistent flag on
1132 GNUNET_SERVER_client_persist_ (struct GNUNET_SERVER_Client *client)
1134 client->persist = GNUNET_YES;
1138 * Resume receiving from this client, we are done processing the
1139 * current request. This function must be called from within each
1140 * GNUNET_SERVER_MessageCallback (or its respective continuations).
1142 * @param client client we were processing a message of
1143 * @param success GNUNET_OK to keep the connection open and
1144 * continue to receive
1145 * GNUNET_NO to close the connection (normal behavior)
1146 * GNUNET_SYSERR to close the connection (signal
1150 GNUNET_SERVER_receive_done (struct GNUNET_SERVER_Client *client, int success)
1154 GNUNET_assert (client->suspended > 0);
1155 client->suspended--;
1156 if (success != GNUNET_OK)
1159 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1160 "GNUNET_SERVER_receive_done called with failure indication\n");
1162 GNUNET_SERVER_client_disconnect (client);
1165 if (client->suspended > 0)
1168 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1169 "GNUNET_SERVER_receive_done called, but more clients pending\n");
1173 if (client->in_process_client_buffer == GNUNET_YES)
1176 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1177 "GNUNET_SERVER_receive_done called while still in processing loop\n");
1181 if (client->server == NULL)
1183 GNUNET_SERVER_client_disconnect (client);
1187 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1188 "GNUNET_SERVER_receive_done causes restart in reading from the socket\n");
1190 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == client->restart_task);
1191 client->restart_task = GNUNET_SCHEDULER_add_now (client->server->sched,
1192 &restart_processing,
1198 * Configure this server's connections to continue handling client
1199 * requests as usual even after we get a shutdown signal. The change
1200 * only applies to clients that connect to the server from the outside
1201 * using TCP after this call. Clients managed previously or those
1202 * added using GNUNET_SERVER_connect_socket and
1203 * GNUNET_SERVER_connect_callback are not affected by this option.
1205 * @param h server handle
1206 * @param do_ignore GNUNET_YES to ignore, GNUNET_NO to restore default
1209 GNUNET_SERVER_ignore_shutdown (struct GNUNET_SERVER_Handle *h, int do_ignore)
1211 h->clients_ignore_shutdown = do_ignore;
1214 /* end of server.c */