2 This file is part of GNUnet
3 (C) 2008--2012 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.
22 * @file testbed/testbed_api.c
23 * @brief API for accessing the GNUnet testing service.
24 * This library is supposed to make it easier to write
25 * testcases and script large-scale benchmarks.
26 * @author Christian Grothoff
27 * @author Sree Harsha Totakura
32 #include "gnunet_testbed_service.h"
33 #include "gnunet_core_service.h"
34 #include "gnunet_constants.h"
35 #include "gnunet_transport_service.h"
36 #include "gnunet_hello_lib.h"
40 #include "testbed_api.h"
41 #include "testbed_api_hosts.h"
42 #include "testbed_api_peers.h"
45 * Generic logging shorthand
47 #define LOG(kind, ...) \
48 GNUNET_log_from (kind, "testbed-api", __VA_ARGS__);
53 #define LOG_DEBUG(...) \
54 LOG (GNUNET_ERROR_TYPE_DEBUG, __VA_ARGS__);
57 * Relative time seconds shorthand
59 #define TIME_REL_SECS(sec) \
60 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, sec)
64 * Default server message sending retry timeout
66 #define TIMEOUT_REL TIME_REL_SECS(1)
70 * The message queue for sending messages to the controller service
75 * The message to be sent
77 struct GNUNET_MessageHeader *msg;
80 * next pointer for DLL
82 struct MessageQueue *next;
85 * prev pointer for DLL
87 struct MessageQueue *prev;
92 * Structure for a controller link
97 * The next ptr for DLL
99 struct ControllerLink *next;
102 * The prev ptr for DLL
104 struct ControllerLink *prev;
107 * The host which will be referred in the peer start request. This is the
108 * host where the peer should be started
110 struct GNUNET_TESTBED_Host *delegated_host;
113 * The host which will contacted to delegate the peer start request
115 struct GNUNET_TESTBED_Host *slave_host;
118 * The configuration to be used to connect to slave host
120 const struct GNUNET_CONFIGURATION_Handle *slave_cfg;
123 * GNUNET_YES if the slave should be started (and stopped) by us; GNUNET_NO
124 * if we are just allowed to use the slave via TCP/IP
131 * handle for host registration
133 struct GNUNET_TESTBED_HostRegistrationHandle
136 * The host being registered
138 struct GNUNET_TESTBED_Host *host;
141 * The controller at which this host is being registered
143 struct GNUNET_TESTBED_Controller *c;
146 * The Registartion completion callback
148 GNUNET_TESTBED_HostRegistrationCompletion cc;
151 * The closure for above callback
158 * Handler for GNUNET_MESSAGE_TYPE_TESTBED_ADDHOSTCONFIRM message from
159 * controller (testbed service)
161 * @param c the controller handler
162 * @param msg message received
163 * @return GNUNET_YES if we can continue receiving from service; GNUNET_NO if
167 handle_addhostconfirm (struct GNUNET_TESTBED_Controller *c,
168 const struct GNUNET_TESTBED_HostConfirmedMessage *msg)
170 struct GNUNET_TESTBED_HostRegistrationHandle *rh;
179 if (GNUNET_TESTBED_host_get_id_ (rh->host) != ntohl (msg->host_id))
181 LOG_DEBUG ("Mismatch in host id's %u, %u of host confirm msg\n",
182 GNUNET_TESTBED_host_get_id_ (rh->host), ntohl (msg->host_id));
186 msg_size = ntohs (msg->header.size);
187 if (sizeof (struct GNUNET_TESTBED_HostConfirmedMessage) == msg_size)
189 LOG_DEBUG ("Host %u successfully registered\n", ntohl (msg->host_id));
190 GNUNET_TESTBED_mark_host_registered_at_ (rh->host, c);
191 rh->cc (rh->cc_cls, NULL);
195 /* We have an error message */
196 emsg = (char *) &msg[1];
197 if ('\0' != emsg[msg_size -
198 sizeof (struct GNUNET_TESTBED_HostConfirmedMessage)])
204 LOG (GNUNET_ERROR_TYPE_ERROR, _("Adding host %u failed with error: %s\n"),
205 ntohl (msg->host_id), emsg);
206 rh->cc (rh->cc_cls, emsg);
213 * Handler for GNUNET_MESSAGE_TYPE_TESTBED_ADDHOSTCONFIRM message from
214 * controller (testbed service)
216 * @param c the controller handler
217 * @param msg message received
218 * @return GNUNET_YES if we can continue receiving from service; GNUNET_NO if
222 handle_opsuccess (struct GNUNET_TESTBED_Controller *c,
224 GNUNET_TESTBED_GenericOperationSuccessEventMessage *msg)
226 struct GNUNET_TESTBED_Operation *op;
227 struct GNUNET_TESTBED_EventInformation *event;
230 op_id = GNUNET_ntohll (msg->operation_id);
231 LOG_DEBUG ("Operation %ul successful\n", op_id);
232 for (op = c->op_head; NULL != op; op = op->next)
234 if (op->operation_id == op_id)
239 LOG_DEBUG ("Operation not found\n");
243 if (0 != (c->event_mask & (1L << GNUNET_TESTBED_ET_OPERATION_FINISHED)))
244 event = GNUNET_malloc (sizeof (struct GNUNET_TESTBED_EventInformation));
246 event->type = GNUNET_TESTBED_ET_OPERATION_FINISHED;
249 case OP_PEER_DESTROY:
251 struct PeerDestroyData *data;
255 event->details.operation_finished.operation = op;
256 event->details.operation_finished.op_cls = NULL;
257 event->details.operation_finished.emsg = NULL;
258 event->details.operation_finished.pit = GNUNET_TESTBED_PIT_GENERIC;
259 event->details.operation_finished.op_result.generic = NULL;
261 data = (struct PeerDestroyData *) op->data;
262 if (NULL != data->peer->details)
264 if (NULL != data->peer->details->cfg)
265 GNUNET_CONFIGURATION_destroy (data->peer->details->cfg);
268 GNUNET_free (data->peer);
279 c->cc (c->cc_cls, event);
281 GNUNET_CONTAINER_DLL_remove (c->op_head, c->op_tail, op);
288 * Handler for messages from controller (testbed service)
290 * @param cls the controller handler
291 * @param msg message received, NULL on timeout or fatal error
294 message_handler (void *cls, const struct GNUNET_MessageHeader *msg)
296 struct GNUNET_TESTBED_Controller *c = cls;
299 c->in_receive = GNUNET_NO;
300 /* FIXME: Add checks for message integrity */
303 LOG_DEBUG ("Receive timed out or connection to service dropped\n");
307 switch (ntohs (msg->type))
309 case GNUNET_MESSAGE_TYPE_TESTBED_ADDHOSTCONFIRM:
311 handle_addhostconfirm (c, (const struct
312 GNUNET_TESTBED_HostConfirmedMessage *) msg);
314 case GNUNET_MESSAGE_TYPE_TESTBED_GENERICOPSUCCESS:
316 handle_opsuccess (c, (const struct
317 GNUNET_TESTBED_GenericOperationSuccessEventMessage
322 if ((GNUNET_OK == status) && (GNUNET_NO == c->in_receive))
324 c->in_receive = GNUNET_YES;
325 GNUNET_CLIENT_receive (c->client, &message_handler, c,
326 GNUNET_TIME_UNIT_FOREVER_REL);
331 * Function called to notify a client about the connection begin ready to queue
332 * more data. "buf" will be NULL and "size" zero if the connection was closed
333 * for writing in the meantime.
336 * @param size number of bytes available in buf
337 * @param buf where the callee should write the message
338 * @return number of bytes written to buf
341 transmit_ready_notify (void *cls, size_t size, void *buf)
343 struct GNUNET_TESTBED_Controller *c = cls;
344 struct MessageQueue *mq_entry;
347 mq_entry = c->mq_head;
348 GNUNET_assert (NULL != mq_entry);
349 if ((0 == size) && (NULL == buf)) /* Timeout */
351 LOG_DEBUG ("Message sending timed out -- retrying\n");
353 GNUNET_CLIENT_notify_transmit_ready (c->client,
354 ntohs (mq_entry->msg->size),
356 GNUNET_YES, &transmit_ready_notify,
360 GNUNET_assert (ntohs (mq_entry->msg->size) <= size);
361 size = ntohs (mq_entry->msg->size);
362 memcpy (buf, mq_entry->msg, size);
363 LOG_DEBUG ("Message of type: %u and size: %u sent\n",
364 ntohs (mq_entry->msg->type), size);
365 GNUNET_free (mq_entry->msg);
366 GNUNET_CONTAINER_DLL_remove (c->mq_head, c->mq_tail, mq_entry);
367 GNUNET_free (mq_entry);
368 mq_entry = c->mq_head;
369 if (NULL != mq_entry)
371 GNUNET_CLIENT_notify_transmit_ready (c->client,
372 ntohs (mq_entry->msg->size),
374 GNUNET_YES, &transmit_ready_notify,
376 if (GNUNET_NO == c->in_receive)
378 c->in_receive = GNUNET_YES;
379 GNUNET_CLIENT_receive (c->client, &message_handler, c,
380 GNUNET_TIME_UNIT_FOREVER_REL);
387 * Queues a message in send queue for sending to the service
389 * @param controller the handle to the controller
390 * @param msg the message to queue
393 GNUNET_TESTBED_queue_message (struct GNUNET_TESTBED_Controller *controller,
394 struct GNUNET_MessageHeader *msg)
396 struct MessageQueue *mq_entry;
400 type = ntohs (msg->type);
401 size = ntohs (msg->size);
402 GNUNET_assert ((GNUNET_MESSAGE_TYPE_TESTBED_INIT <= type) &&
403 (GNUNET_MESSAGE_TYPE_TESTBED_MAX > type));
404 mq_entry = GNUNET_malloc (sizeof (struct MessageQueue));
406 LOG (GNUNET_ERROR_TYPE_DEBUG,
407 "Queueing message of type %u, size %u for sending\n", type,
409 GNUNET_CONTAINER_DLL_insert_tail (controller->mq_head, controller->mq_tail,
411 if (NULL == controller->th)
413 GNUNET_CLIENT_notify_transmit_ready (controller->client, size,
415 GNUNET_YES, &transmit_ready_notify,
421 * Handle for controller process
423 struct GNUNET_TESTBED_ControllerProc
428 struct GNUNET_TESTBED_HelperHandle *helper;
434 * Starts a controller process at the host
436 * @param host the host where the controller has to be started; NULL for localhost
437 * @return the controller process handle
439 struct GNUNET_TESTBED_ControllerProc *
440 GNUNET_TESTBED_controller_start (struct GNUNET_TESTBED_Host *host)
442 struct GNUNET_TESTBED_ControllerProc *cproc;
443 char * const binary_argv[] = {
444 "gnunet-service-testbed",
445 "gnunet-service-testbed",
449 cproc = GNUNET_malloc (sizeof (struct GNUNET_TESTBED_ControllerProc));
450 cproc->helper = GNUNET_TESTBED_host_run_ (host, binary_argv);
451 if (NULL == cproc->helper)
461 * Stop the controller process (also will terminate all peers and controllers
462 * dependent on this controller). This function blocks until the testbed has
463 * been fully terminated (!).
465 * @param cproc the controller process handle
468 GNUNET_TESTBED_controller_stop (struct GNUNET_TESTBED_ControllerProc *cproc)
470 GNUNET_TESTBED_host_stop_ (cproc->helper);
476 * Start a controller process using the given configuration at the
479 * @param cfg configuration to use
480 * @param host host to run the controller on; This should be the same host if
481 * the controller was previously started with
482 * GNUNET_TESTBED_controller_start; NULL for localhost
483 * @param event_mask bit mask with set of events to call 'cc' for;
484 * or-ed values of "1LL" shifted by the
485 * respective 'enum GNUNET_TESTBED_EventType'
486 * (i.e. "(1LL << GNUNET_TESTBED_ET_CONNECT) | ...")
487 * @param cc controller callback to invoke on events
488 * @param cc_cls closure for cc
489 * @return handle to the controller
491 struct GNUNET_TESTBED_Controller *
492 GNUNET_TESTBED_controller_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
493 struct GNUNET_TESTBED_Host *host,
495 GNUNET_TESTBED_ControllerCallback cc,
498 struct GNUNET_TESTBED_Controller *controller;
499 struct GNUNET_TESTBED_InitMessage *msg;
501 controller = GNUNET_malloc (sizeof (struct GNUNET_TESTBED_Controller));
503 controller->cc_cls = cc_cls;
504 controller->event_mask = event_mask;
505 controller->cfg = GNUNET_CONFIGURATION_dup (cfg);
506 controller->client = GNUNET_CLIENT_connect ("testbed", controller->cfg);
507 if (NULL == controller->client)
509 GNUNET_TESTBED_controller_disconnect (controller);
514 host = GNUNET_TESTBED_host_create_by_id_ (0);
517 LOG (GNUNET_ERROR_TYPE_WARNING,
518 "Treating NULL host as localhost. Multiple references to localhost. "
519 " May break when localhost freed before calling disconnect \n");
520 host = GNUNET_TESTBED_host_lookup_by_id_ (0);
524 controller->aux_host = GNUNET_YES;
527 GNUNET_assert (NULL != host);
528 msg = GNUNET_malloc (sizeof (struct GNUNET_TESTBED_InitMessage));
529 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TESTBED_INIT);
530 msg->header.size = htons (sizeof (struct GNUNET_TESTBED_InitMessage));
531 msg->host_id = htonl (GNUNET_TESTBED_host_get_id_ (host));
532 msg->event_mask = GNUNET_htonll (controller->event_mask);
533 GNUNET_TESTBED_queue_message (controller, (struct GNUNET_MessageHeader *) msg);
539 * Configure shared services at a controller. Using this function,
540 * you can specify that certain services (such as "resolver")
541 * should not be run for each peer but instead be shared
542 * across N peers on the specified host. This function
543 * must be called before any peers are created at the host.
545 * @param controller controller to configure
546 * @param service_name name of the service to share
547 * @param num_peers number of peers that should share one instance
548 * of the specified service (1 for no sharing is the default),
549 * use 0 to disable the service
552 GNUNET_TESTBED_controller_configure_sharing (struct GNUNET_TESTBED_Controller *controller,
553 const char *service_name,
556 struct GNUNET_TESTBED_ConfigureSharedServiceMessage *msg;
557 uint16_t service_name_size;
560 service_name_size = strlen (service_name) + 1;
561 msg_size = sizeof (struct GNUNET_TESTBED_ConfigureSharedServiceMessage)
563 msg = GNUNET_malloc (msg_size);
564 msg->header.size = htons (msg_size);
565 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TESTBED_SERVICESHARE);
566 msg->host_id = htonl (GNUNET_TESTBED_host_get_id_ (controller->host));
567 msg->num_peers = htonl (num_peers);
568 memcpy (&msg[1], service_name, service_name_size);
569 GNUNET_TESTBED_queue_message (controller, (struct GNUNET_MessageHeader *) msg);
574 * disconnects from the controller.
576 * @param controller handle to controller to stop
579 GNUNET_TESTBED_controller_disconnect (struct GNUNET_TESTBED_Controller *controller)
581 struct MessageQueue *mq_entry;
583 if (NULL != controller->th)
584 GNUNET_CLIENT_notify_transmit_ready_cancel (controller->th);
585 /* Clear the message queue */
586 while (NULL != (mq_entry = controller->mq_head))
588 GNUNET_CONTAINER_DLL_remove (controller->mq_head,
591 GNUNET_free (mq_entry->msg);
592 GNUNET_free (mq_entry);
594 if (NULL != controller->client)
595 GNUNET_CLIENT_disconnect (controller->client);
596 GNUNET_CONFIGURATION_destroy (controller->cfg);
597 if (GNUNET_YES == controller->aux_host)
598 GNUNET_TESTBED_host_destroy (controller->host);
599 GNUNET_free (controller);
604 * Register a host with the controller
606 * @param controller the controller handle
607 * @param host the host to register
608 * @param cc the completion callback to call to inform the status of
609 * registration. After calling this callback the registration handle
610 * will be invalid. Cannot be NULL.
611 * @param cc_cls the closure for the cc
612 * @return handle to the host registration which can be used to cancel the
615 struct GNUNET_TESTBED_HostRegistrationHandle *
616 GNUNET_TESTBED_register_host (struct GNUNET_TESTBED_Controller *controller,
617 struct GNUNET_TESTBED_Host *host,
618 GNUNET_TESTBED_HostRegistrationCompletion cc,
621 struct GNUNET_TESTBED_HostRegistrationHandle *rh;
622 struct GNUNET_TESTBED_AddHostMessage *msg;
623 const char *username;
624 const char *hostname;
626 uint16_t user_name_length;
628 if (NULL != controller->rh)
630 hostname = GNUNET_TESTBED_host_get_hostname_ (host);
631 if (GNUNET_YES == GNUNET_TESTBED_is_host_registered_ (host, controller))
633 LOG (GNUNET_ERROR_TYPE_WARNING,
634 "Host hostname: %s already registered\n",
635 (NULL == hostname) ? "localhost" : hostname);
638 rh = GNUNET_malloc (sizeof (struct GNUNET_TESTBED_HostRegistrationHandle));
641 GNUNET_assert (NULL != cc);
645 username = GNUNET_TESTBED_host_get_username_ (host);
646 msg_size = (sizeof (struct GNUNET_TESTBED_AddHostMessage));
647 user_name_length = 0;
648 if (NULL != username)
650 user_name_length = strlen (username) + 1;
651 msg_size += user_name_length;
653 /* FIXME: what happens when hostname is NULL? localhost */
654 GNUNET_assert (NULL != hostname);
655 msg_size += strlen (hostname) + 1;
656 msg = GNUNET_malloc (msg_size);
657 msg->header.size = htons (msg_size);
658 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TESTBED_ADDHOST);
659 msg->host_id = htonl (GNUNET_TESTBED_host_get_id_ (host));
660 msg->ssh_port = htons (GNUNET_TESTBED_host_get_ssh_port_ (host));
661 msg->user_name_length = htons (user_name_length);
662 if (NULL != username)
663 memcpy (&msg[1], username, user_name_length);
664 strcpy (((void *) &msg[1]) + user_name_length, hostname);
665 GNUNET_TESTBED_queue_message (controller, (struct GNUNET_MessageHeader *) msg);
671 * Cancel the pending registration. Note that if the registration message is
672 * already sent to the service the cancellation has only the effect that the
673 * registration completion callback for the registration is never called.
675 * @param handle the registration handle to cancel
678 GNUNET_TESTBED_cancel_registration (struct GNUNET_TESTBED_HostRegistrationHandle
681 if (handle != handle->c->rh)
686 handle->c->rh = NULL;
687 GNUNET_free (handle);
692 * Same as the GNUNET_TESTBED_controller_link, however expects configuration in
693 * serialized and compressed
695 * @param master handle to the master controller who creates the association
696 * @param delegated_host requests to which host should be delegated; cannot be NULL
697 * @param slave_host which host is used to run the slave controller; use NULL to
698 * make the master controller connect to the delegated host
699 * @param sxcfg serialized and compressed configuration
700 * @param sxcfg_size the size scfg
701 * @param scfg_size the size of uncompressed serialized configuration
702 * @param is_subordinate GNUNET_YES if the controller at delegated_host should
703 * be started by the master controller; GNUNET_NO if we are just
704 * allowed to use the slave via TCP/IP
707 GNUNET_TESTBED_controller_link_2 (struct GNUNET_TESTBED_Controller *master,
708 struct GNUNET_TESTBED_Host *delegated_host,
709 struct GNUNET_TESTBED_Host *slave_host,
715 struct GNUNET_TESTBED_ControllerLinkMessage *msg;
718 GNUNET_assert (GNUNET_YES ==
719 GNUNET_TESTBED_is_host_registered_ (delegated_host, master));
720 if ((NULL != slave_host) && (0 != GNUNET_TESTBED_host_get_id_ (slave_host)))
721 GNUNET_assert (GNUNET_YES ==
722 GNUNET_TESTBED_is_host_registered_ (slave_host, master));
723 msg_size = sxcfg_size + sizeof (struct GNUNET_TESTBED_ControllerLinkMessage);
724 msg = GNUNET_malloc (msg_size);
725 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TESTBED_LCONTROLLERS);
726 msg->header.size = htons (msg_size);
727 msg->delegated_host_id = htonl (GNUNET_TESTBED_host_get_id_ (delegated_host));
728 msg->slave_host_id = htonl (GNUNET_TESTBED_host_get_id_
729 ((NULL != slave_host) ? slave_host : master->host));
730 msg->config_size = htons ((uint16_t) scfg_size);
731 msg->is_subordinate = (GNUNET_YES == is_subordinate) ? 1 : 0;
732 memcpy (&msg[1], sxcfg, sxcfg_size);
733 GNUNET_TESTBED_queue_message (master, (struct GNUNET_MessageHeader *) msg);
738 * Compresses given configuration using zlib compress
740 * @param config the serialized configuration
741 * @param size the size of config
742 * @param xconfig will be set to the compressed configuration (memory is fresly
744 * @return the size of the xconfig
747 GNUNET_TESTBED_compress_config (const char *config, size_t size,
752 xsize = compressBound ((uLong) size);
753 *xconfig = GNUNET_malloc (xsize);
754 GNUNET_assert (Z_OK ==
755 compress2 ((Bytef *)* xconfig, (uLongf *) &xsize,
756 (const Bytef *) config, (uLongf) size,
763 * Create a link from slave controller to delegated controller. Whenever the
764 * master controller is asked to start a peer at the delegated controller the
765 * request will be routed towards slave controller (if a route exists). The
766 * slave controller will then route it to the delegated controller. The
767 * configuration of the slave controller is given and to be used to either
768 * create the slave controller or to connect to an existing slave controller
769 * process. 'is_subordinate' specifies if the given slave controller should be
770 * started and managed by the master controller, or if the slave already has a
771 * master and this is just a secondary master that is also allowed to use the
774 * @param master handle to the master controller who creates the association
775 * @param delegated_host requests to which host should be delegated
776 * @param slave_host which host is used to run the slave controller
777 * @param slave_cfg configuration to use for the slave controller
778 * @param is_subordinate GNUNET_YES if the slave should be started (and stopped)
779 * by the master controller; GNUNET_NO if we are just
780 * allowed to use the slave via TCP/IP
783 GNUNET_TESTBED_controller_link (struct GNUNET_TESTBED_Controller *master,
784 struct GNUNET_TESTBED_Host *delegated_host,
785 struct GNUNET_TESTBED_Host *slave_host,
786 const struct GNUNET_CONFIGURATION_Handle *slave_cfg,
794 GNUNET_assert (GNUNET_YES ==
795 GNUNET_TESTBED_is_host_registered_ (delegated_host, master));
796 if ((NULL != slave_host) && (0 != GNUNET_TESTBED_host_get_id_ (slave_host)))
797 GNUNET_assert (GNUNET_YES ==
798 GNUNET_TESTBED_is_host_registered_ (slave_host, master));
799 config = GNUNET_CONFIGURATION_serialize (slave_cfg, &config_size);
800 cc_size = GNUNET_TESTBED_compress_config (config, config_size, &cconfig);
801 GNUNET_free (config);
802 GNUNET_assert ((UINT16_MAX -
803 sizeof (struct GNUNET_TESTBED_ControllerLinkMessage))
804 >= cc_size); /* Configuration doesn't fit in 1 message */
805 GNUNET_TESTBED_controller_link_2 (master, delegated_host, slave_host,
806 (const char *) cconfig,
807 cc_size, config_size, is_subordinate);
808 GNUNET_free (cconfig);
813 * Ask the testbed controller to write the current overlay topology to
814 * a file. Naturally, the file will only contain a snapshot as the
815 * topology may evolve all the time.
817 * @param controller overlay controller to inspect
818 * @param filename name of the file the topology should
822 GNUNET_TESTBED_overlay_write_topology_to_file (struct GNUNET_TESTBED_Controller *controller,
823 const char *filename)
830 /* end of testbed_api.c */