2 This file is part of GNUnet
3 (C) 2008, 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 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 include/gnunet_testing_lib.h
23 * @brief convenience API for writing testcases for GNUnet
24 * Many testcases need to start and stop gnunetd,
25 * and this library is supposed to make that easier
26 * for TESTCASES. Normal programs should always
27 * use functions from gnunet_{util,arm}_lib.h. This API is
28 * ONLY for writing testcases!
29 * @author Christian Grothoff
32 #ifndef GNUNET_TESTING_LIB_H
33 #define GNUNET_TESTING_LIB_H
35 #include "gnunet_util_lib.h"
36 #include "gnunet_statistics_service.h"
41 #if 0 /* keep Emacsens' auto-indent happy */
46 #define HOSTKEYFILESIZE 914
49 * Handle for a GNUnet daemon (technically a set of
50 * daemons; the handle is really for the master ARM
51 * daemon) started by the testing library.
53 struct GNUNET_TESTING_Daemon;
56 * Linked list of hostnames and ports to use for starting daemons.
58 struct GNUNET_TESTING_Host
61 * Pointer to next item in the list.
63 struct GNUNET_TESTING_Host *next;
66 * Hostname to connect to.
71 * Username to use when connecting (may be null).
76 * Port to use for SSH connection (used for ssh
77 * connection forwarding, 0 to let ssh decide)
83 * Prototype of a function that will be called whenever
84 * a daemon was started by the testing library.
87 * @param id identifier for the daemon, NULL on error
88 * @param d handle for the daemon
89 * @param emsg error message (NULL on success)
91 typedef void (*GNUNET_TESTING_NotifyHostkeyCreated)(void *cls,
92 const struct GNUNET_PeerIdentity *id,
93 struct GNUNET_TESTING_Daemon *d,
97 * Prototype of a function that will be called whenever
98 * a daemon was started by the testing library.
101 * @param id identifier for the daemon, NULL on error
102 * @param cfg configuration used by this daemon
103 * @param d handle for the daemon
104 * @param emsg error message (NULL on success)
106 typedef void (*GNUNET_TESTING_NotifyDaemonRunning)(void *cls,
107 const struct GNUNET_PeerIdentity *id,
108 const struct GNUNET_CONFIGURATION_Handle *cfg,
109 struct GNUNET_TESTING_Daemon *d,
114 * Handle to an entire testbed of GNUnet peers.
116 struct GNUNET_TESTING_Testbed;
119 * Phases of starting GNUnet on a system.
121 enum GNUNET_TESTING_StartPhase
124 * Copy the configuration file to the target system.
129 * Configuration file has been copied, generate hostkey.
134 * Create the hostkey for the peer.
139 * Hostkey generated, wait for topology to be finished.
144 * Topology has been created, now start ARM.
149 * ARM has been started, check that it has properly daemonized and
150 * then try to connect to the CORE service (which should be
151 * auto-started by ARM).
156 * We're waiting for CORE to start.
161 * Core has notified us that we've established a connection to the service.
162 * The main FSM halts here and waits to be moved to UPDATE or CLEANUP.
167 * We've been asked to terminate the instance and are now waiting for
168 * the remote command to stop the gnunet-arm process and delete temporary
174 * We've received a configuration update and are currently waiting for
175 * the copy process for the update to complete. Once it is, we will
176 * return to "SP_START_DONE" (and rely on ARM to restart all affected
183 * Prototype of a function that will be called when a
184 * particular operation was completed the testing library.
187 * @param emsg NULL on success
189 typedef void (*GNUNET_TESTING_NotifyCompletion)(void *cls,
193 * Prototype of a function that will be called with the
194 * number of connections created for a particular topology.
197 * @param num_connections the number of connections created
199 typedef void (*GNUNET_TESTING_NotifyConnections)(void *cls,
200 unsigned int num_connections);
203 * Handle for a GNUnet daemon (technically a set of
204 * daemons; the handle is really for the master ARM
205 * daemon) started by the testing library.
207 struct GNUNET_TESTING_Daemon
212 struct GNUNET_CONFIGURATION_Handle *cfg;
215 * At what time to give up starting the peer
217 struct GNUNET_TIME_Absolute max_timeout;
220 * Host to run GNUnet on.
225 * Port to use for ssh, NULL to let system choose default.
230 * Result of GNUNET_i2s of this peer,
236 * Username we are using.
241 * Name of the configuration file
246 * Callback to inform initiator that the peer's
247 * hostkey has been created.
249 GNUNET_TESTING_NotifyHostkeyCreated hostkey_callback;
252 * Closure for hostkey creation callback.
257 * Function to call when the peer is running.
259 GNUNET_TESTING_NotifyDaemonRunning cb;
267 * Arguments from "daemon_stop" call.
269 GNUNET_TESTING_NotifyCompletion dead_cb;
272 * Closure for 'dead_cb'.
277 * Arguments from "daemon_stop" call.
279 GNUNET_TESTING_NotifyCompletion update_cb;
282 * Closure for 'update_cb'.
287 * Identity of this peer (once started).
289 struct GNUNET_PeerIdentity id;
292 * Flag to indicate that we've already been asked
293 * to terminate (but could not because some action
294 * was still pending).
299 * PID of the process that we started last.
301 struct GNUNET_OS_Process *proc;
304 * In which phase are we during the start of
307 enum GNUNET_TESTING_StartPhase phase;
310 * ID of the current task.
312 GNUNET_SCHEDULER_TaskIdentifier task;
315 * Handle to the server.
317 struct GNUNET_CORE_Handle *server;
320 * Handle to the transport service of this peer
322 struct GNUNET_TRANSPORT_Handle *th;
325 * HELLO message for this peer
327 struct GNUNET_HELLO_Message *hello;
330 * Handle to a pipe for reading the hostkey.
332 struct GNUNET_DISK_PipeHandle *pipe_stdout;
335 * Output from gnunet-peerinfo is read into this buffer.
337 char hostkeybuf[105];
340 * Current position in 'hostkeybuf' (for reading from gnunet-peerinfo)
342 unsigned int hostkeybufpos;
345 * Set to GNUNET_YES once the peer is up.
350 * Used to tell shutdown not to remove configuration for the peer
351 * (if it's going to be restarted later)
358 * Handle to a group of GNUnet peers.
360 struct GNUNET_TESTING_PeerGroup;
364 * Prototype of a function that will be called whenever
365 * two daemons are connected by the testing library.
368 * @param first peer id for first daemon
369 * @param second peer id for the second daemon
370 * @param distance distance between the connected peers
371 * @param first_cfg config for the first daemon
372 * @param second_cfg config for the second daemon
373 * @param first_daemon handle for the first daemon
374 * @param second_daemon handle for the second daemon
375 * @param emsg error message (NULL on success)
377 typedef void (*GNUNET_TESTING_NotifyConnection)(void *cls,
378 const struct GNUNET_PeerIdentity *first,
379 const struct GNUNET_PeerIdentity *second,
381 const struct GNUNET_CONFIGURATION_Handle *first_cfg,
382 const struct GNUNET_CONFIGURATION_Handle *second_cfg,
383 struct GNUNET_TESTING_Daemon *first_daemon,
384 struct GNUNET_TESTING_Daemon *second_daemon,
388 * Prototype of a callback function indicating that two peers
389 * are currently connected.
392 * @param first peer id for first daemon
393 * @param second peer id for the second daemon
394 * @param distance distance between the connected peers
395 * @param emsg error message (NULL on success)
397 typedef void (*GNUNET_TESTING_NotifyTopology)(void *cls,
398 const struct GNUNET_PeerIdentity *first,
399 const struct GNUNET_PeerIdentity *second,
403 * Starts a GNUnet daemon. GNUnet must be installed on the target
404 * system and available in the PATH. The machine must furthermore be
405 * reachable via "ssh" (unless the hostname is "NULL") without the
406 * need to enter a password.
408 * @param cfg configuration to use
409 * @param timeout how long to wait starting up peers
410 * @param hostname name of the machine where to run GNUnet
411 * (use NULL for localhost).
412 * @param ssh_username ssh username to use when connecting to hostname
413 * @param sshport port to pass to ssh process when connecting to hostname
414 * @param hostkey pointer to a hostkey to be written to disk (instead of being generated)
415 * @param hostkey_callback function to call once the hostkey has been
416 * generated for this peer, but it hasn't yet been started
417 * (NULL to start immediately, otherwise waits on GNUNET_TESTING_daemon_continue_start)
418 * @param hostkey_cls closure for hostkey callback
419 * @param cb function to call once peer is up, or failed to start
420 * @param cb_cls closure for cb
421 * @return handle to the daemon (actual start will be completed asynchronously)
423 struct GNUNET_TESTING_Daemon *
424 GNUNET_TESTING_daemon_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
425 struct GNUNET_TIME_Relative timeout,
426 const char *hostname,
427 const char *ssh_username,
430 GNUNET_TESTING_NotifyHostkeyCreated
431 hostkey_callback, void *hostkey_cls,
432 GNUNET_TESTING_NotifyDaemonRunning cb,
436 * Continues GNUnet daemon startup when user wanted to be notified
437 * once a hostkey was generated (for creating friends files, blacklists,
440 * @param daemon the daemon to finish starting
443 GNUNET_TESTING_daemon_continue_startup(struct GNUNET_TESTING_Daemon *daemon);
446 * Check whether the given daemon is running.
448 * @param daemon the daemon to check
450 * @return GNUNET_YES if the daemon is up, GNUNET_NO if the
451 * daemon is down, GNUNET_SYSERR on error.
454 GNUNET_TESTING_daemon_running (struct GNUNET_TESTING_Daemon *daemon);
457 * Restart (stop and start) a GNUnet daemon.
459 * @param d the daemon that should be restarted
460 * @param cb function called once the daemon is (re)started
461 * @param cb_cls closure for cb
464 GNUNET_TESTING_daemon_restart (struct GNUNET_TESTING_Daemon *d,
465 GNUNET_TESTING_NotifyDaemonRunning cb, void *cb_cls);
468 * Start a peer that has previously been stopped using the daemon_stop
469 * call (and files weren't deleted and the allow restart flag)
471 * @param daemon the daemon to start (has been previously stopped)
472 * @param timeout how long to wait for restart
473 * @param cb the callback for notification when the peer is running
474 * @param cb_cls closure for the callback
477 GNUNET_TESTING_daemon_start_stopped (struct GNUNET_TESTING_Daemon *daemon,
478 struct GNUNET_TIME_Relative timeout,
479 GNUNET_TESTING_NotifyDaemonRunning cb,
483 * Get a certain testing daemon handle.
485 * @param pg handle to the set of running peers
486 * @param position the number of the peer to return
488 struct GNUNET_TESTING_Daemon *
489 GNUNET_TESTING_daemon_get (struct GNUNET_TESTING_PeerGroup *pg,
490 unsigned int position);
493 * Get a daemon by peer identity, so callers can
494 * retrieve the daemon without knowing it's offset.
496 * @param pg the peer group to retrieve the daemon from
497 * @param peer_id the peer identity of the daemon to retrieve
499 * @return the daemon on success, or NULL if no such peer identity is found
501 struct GNUNET_TESTING_Daemon *
502 GNUNET_TESTING_daemon_get_by_id (struct GNUNET_TESTING_PeerGroup *pg,
503 struct GNUNET_PeerIdentity *peer_id);
506 * Stops a GNUnet daemon.
508 * @param d the daemon that should be stopped
509 * @param timeout how long to wait for process for shutdown to complete
510 * @param cb function called once the daemon was stopped
511 * @param cb_cls closure for cb
512 * @param delete_files GNUNET_YES to remove files, GNUNET_NO
513 * to leave them (i.e. for restarting at a later time,
514 * or logfile inspection once finished)
515 * @param allow_restart GNUNET_YES to restart peer later (using this API)
516 * GNUNET_NO to kill off and clean up for good
519 GNUNET_TESTING_daemon_stop (struct GNUNET_TESTING_Daemon *d,
520 struct GNUNET_TIME_Relative timeout,
521 GNUNET_TESTING_NotifyCompletion cb, void *cb_cls,
522 int delete_files, int allow_restart);
526 * Changes the configuration of a GNUnet daemon.
528 * @param d the daemon that should be modified
529 * @param cfg the new configuration for the daemon
530 * @param cb function called once the configuration was changed
531 * @param cb_cls closure for cb
533 void GNUNET_TESTING_daemon_reconfigure (struct GNUNET_TESTING_Daemon *d,
534 struct GNUNET_CONFIGURATION_Handle *cfg,
535 GNUNET_TESTING_NotifyCompletion cb,
540 * Establish a connection between two GNUnet daemons.
542 * @param d1 handle for the first daemon
543 * @param d2 handle for the second daemon
544 * @param timeout how long is the connection attempt
546 * @param max_connect_attempts how many times should we try to reconnect
548 * @param cb function to call at the end
549 * @param cb_cls closure for cb
551 void GNUNET_TESTING_daemons_connect (struct GNUNET_TESTING_Daemon *d1,
552 struct GNUNET_TESTING_Daemon *d2,
553 struct GNUNET_TIME_Relative timeout,
554 unsigned int max_connect_attempts,
555 GNUNET_TESTING_NotifyConnection cb,
562 * Start count gnunetd processes with the same set of transports and
563 * applications. The port numbers (any option called "PORT") will be
564 * adjusted to ensure that no two peers running on the same system
565 * have the same port(s) in their respective configurations.
567 * @param cfg configuration template to use
568 * @param total number of daemons to start
569 * @param timeout total time allowed for peers to start
570 * @param hostkey_callback function to call on each peers hostkey generation
571 * if NULL, peers will be started by this call, if non-null,
572 * GNUNET_TESTING_daemons_continue_startup must be called after
573 * successful hostkey generation
574 * @param hostkey_cls closure for hostkey callback
575 * @param cb function to call on each daemon that was started
576 * @param cb_cls closure for cb
577 * @param connect_callback function to call each time two hosts are connected
578 * @param connect_callback_cls closure for connect_callback
579 * @param hostnames linked list of hosts to use to start peers on (NULL to run on localhost only)
581 * @return NULL on error, otherwise handle to control peer group
583 struct GNUNET_TESTING_PeerGroup *
584 GNUNET_TESTING_daemons_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
586 struct GNUNET_TIME_Relative timeout,
587 GNUNET_TESTING_NotifyHostkeyCreated hostkey_callback,
589 GNUNET_TESTING_NotifyDaemonRunning cb,
591 GNUNET_TESTING_NotifyConnection
592 connect_callback, void *connect_callback_cls,
593 const struct GNUNET_TESTING_Host *hostnames);
596 * Function which continues a peer group starting up
597 * after successfully generating hostkeys for each peer.
599 * @param pg the peer group to continue starting
602 GNUNET_TESTING_daemons_continue_startup(struct GNUNET_TESTING_PeerGroup *pg);
605 * Restart all peers in the given group.
607 * @param pg the handle to the peer group
608 * @param callback function to call on completion (or failure)
609 * @param callback_cls closure for the callback function
612 GNUNET_TESTING_daemons_restart (struct GNUNET_TESTING_PeerGroup *pg,
613 GNUNET_TESTING_NotifyCompletion callback,
618 * Shutdown all peers started in the given group.
620 * @param pg handle to the peer group
621 * @param timeout how long to wait for shutdown
622 * @param cb callback to notify upon success or failure
623 * @param cb_cls closure for cb
626 GNUNET_TESTING_daemons_stop (struct GNUNET_TESTING_PeerGroup *pg,
627 struct GNUNET_TIME_Relative timeout,
628 GNUNET_TESTING_NotifyCompletion cb,
633 * Count the number of running peers.
635 * @param pg handle for the peer group
637 * @return the number of currently running peers in the peer group
640 GNUNET_TESTING_daemons_running (struct GNUNET_TESTING_PeerGroup *pg);
643 * Simulate churn by stopping some peers (and possibly
644 * re-starting others if churn is called multiple times). This
645 * function can only be used to create leave-join churn (peers "never"
646 * leave for good). First "voff" random peers that are currently
647 * online will be taken offline; then "von" random peers that are then
648 * offline will be put back online. No notifications will be
649 * generated for any of these operations except for the callback upon
650 * completion. Note that the implementation is at liberty to keep
651 * the ARM service itself (but none of the other services or daemons)
652 * running even though the "peer" is being varied offline.
654 * @param pg handle for the peer group
655 * @param voff number of peers that should go offline
656 * @param von number of peers that should come back online;
657 * must be zero on first call (since "testbed_start"
658 * always starts all of the peers)
659 * @param timeout how long to wait for operations to finish before
661 * @param cb function to call at the end
662 * @param cb_cls closure for cb
665 GNUNET_TESTING_daemons_churn (struct GNUNET_TESTING_PeerGroup *pg,
668 struct GNUNET_TIME_Relative timeout,
669 GNUNET_TESTING_NotifyCompletion cb,
673 * Callback function to process statistic values.
676 * @param peer the peer the statistics belong to
677 * @param subsystem name of subsystem that created the statistic
678 * @param name the name of the datum
679 * @param value the current value
680 * @param is_persistent GNUNET_YES if the value is persistent, GNUNET_NO if not
681 * @return GNUNET_OK to continue, GNUNET_SYSERR to abort iteration
683 typedef int (*GNUNET_TESTING_STATISTICS_Iterator) (void *cls,
684 const struct GNUNET_PeerIdentity *peer,
685 const char *subsystem,
691 * Iterate over all (running) peers in the peer group, retrieve
692 * all statistics from each.
695 GNUNET_TESTING_get_statistics (struct GNUNET_TESTING_PeerGroup *pg,
696 GNUNET_STATISTICS_Callback cont,
697 GNUNET_TESTING_STATISTICS_Iterator proc, void *cls);
700 * Topologies supported for testbeds.
702 enum GNUNET_TESTING_Topology
705 * A clique (everyone connected to everyone else).
707 GNUNET_TESTING_TOPOLOGY_CLIQUE,
710 * Small-world network (2d torus plus random links).
712 GNUNET_TESTING_TOPOLOGY_SMALL_WORLD,
715 * Small-world network (ring plus random links).
717 GNUNET_TESTING_TOPOLOGY_SMALL_WORLD_RING,
722 GNUNET_TESTING_TOPOLOGY_RING,
727 GNUNET_TESTING_TOPOLOGY_2D_TORUS,
732 GNUNET_TESTING_TOPOLOGY_ERDOS_RENYI,
735 * Certain percentage of peers are unable to communicate directly
736 * replicating NAT conditions
738 GNUNET_TESTING_TOPOLOGY_INTERNAT,
741 * Scale free topology.
743 GNUNET_TESTING_TOPOLOGY_SCALE_FREE,
746 * Straight line topology.
748 GNUNET_TESTING_TOPOLOGY_LINE,
751 * All peers are disconnected.
753 GNUNET_TESTING_TOPOLOGY_NONE,
756 * Read a topology from a given file.
758 GNUNET_TESTING_TOPOLOGY_FROM_FILE
762 * Options for connecting a topology.
764 enum GNUNET_TESTING_TopologyOption
767 * Try to connect all peers specified in the topology.
769 GNUNET_TESTING_TOPOLOGY_OPTION_ALL,
772 * Choose a random subset of connections to create.
774 GNUNET_TESTING_TOPOLOGY_OPTION_RANDOM,
777 * Create at least X connections for each peer.
779 GNUNET_TESTING_TOPOLOGY_OPTION_MINIMUM,
782 * Using a depth first search, create one connection
783 * per peer. If any are missed (graph disconnected)
784 * start over at those peers until all have at least one
787 GNUNET_TESTING_TOPOLOGY_OPTION_DFS,
790 * Find the N closest peers to each allowed peer in the
791 * topology and make sure a connection to those peers
792 * exists in the connect topology.
794 GNUNET_TESTING_TOPOLOGY_OPTION_ADD_CLOSEST,
797 * No options specified.
799 GNUNET_TESTING_TOPOLOGY_OPTION_NONE
804 * Get a topology from a string input.
806 * @param topology where to write the retrieved topology
807 * @param topology_string The string to attempt to
808 * get a configuration value from
809 * @return GNUNET_YES if topology string matched a
810 * known topology, GNUNET_NO if not
813 GNUNET_TESTING_topology_get(enum GNUNET_TESTING_Topology *topology,
814 const char * topology_string);
817 * Get connect topology option from string input.
819 * @param topology_option where to write the retrieved topology
820 * @param topology_string The string to attempt to
821 * get a configuration value from
822 * @return GNUNET_YES if topology string matched a
823 * known topology, GNUNET_NO if not
826 GNUNET_TESTING_topology_option_get(enum GNUNET_TESTING_TopologyOption *topology_option,
827 const char * topology_string);
831 * Takes a peer group and creates a topology based on the
832 * one specified. Creates a topology means generates friend
833 * files for the peers so they can only connect to those allowed
834 * by the topology. This will only have an effect once peers
835 * are started if the FRIENDS_ONLY option is set in the base
838 * Also takes an optional restrict topology which
839 * disallows direct connections UNLESS they are specified in
840 * the restricted topology.
842 * A simple example; if the topology option is set to LINE
843 * peers can ONLY connect in a LINE. However, if the topology
844 * option is set to 2D-torus and the restrict option is set to
845 * line with restrict_transports equal to "tcp udp", then peers
846 * may connect in a 2D-torus, but will be restricted to tcp and
847 * udp connections only in a LINE. Generally it only makes
848 * sense to do this if restrict_topology is a subset of topology.
850 * For testing peer discovery, etc. it is generally better to
851 * leave restrict_topology as GNUNET_TESTING_TOPOLOGY_NONE and
852 * then use the connect_topology function to restrict the initial
855 * @param pg the peer group struct representing the running peers
856 * @param topology which topology to connect the peers in
857 * @param restrict_topology allow only direct connections in this topology,
858 * based on those listed in restrict_transports, set to
859 * GNUNET_TESTING_TOPOLOGY_NONE for no restrictions
860 * @param restrict_transports space delimited list of transports to blacklist
861 * to create restricted topology, NULL for none
863 * @return the maximum number of connections were all allowed peers
864 * connected to each other
867 GNUNET_TESTING_create_topology (struct GNUNET_TESTING_PeerGroup *pg,
868 enum GNUNET_TESTING_Topology topology,
869 enum GNUNET_TESTING_Topology restrict_topology,
870 const char *restrict_transports);
873 * Iterate over all (running) peers in the peer group, retrieve
874 * all connections that each currently has.
876 * @param pg the peer group we are concerned with
877 * @param cb callback for topology information
878 * @param cls closure for callback
881 GNUNET_TESTING_get_topology (struct GNUNET_TESTING_PeerGroup *pg,
882 GNUNET_TESTING_NotifyTopology cb, void *cls);
885 * There are many ways to connect peers that are supported by this function.
886 * To connect peers in the same topology that was created via the
887 * GNUNET_TESTING_create_topology, the topology variable must be set to
888 * GNUNET_TESTING_TOPOLOGY_NONE. If the topology variable is specified,
889 * a new instance of that topology will be generated and attempted to be
890 * connected. This could result in some connections being impossible,
891 * because some topologies are non-deterministic.
893 * @param pg the peer group struct representing the running peers
894 * @param topology which topology to connect the peers in
895 * @param options options for connecting the topology
896 * @param option_modifier modifier for options that take a parameter
897 * @param notify_callback notification to be called once all connections completed
898 * @param notify_cls closure for notification callback
900 * @return the number of connections that will be attempted (multiple of two,
901 * each bidirectional connection counts twice!), GNUNET_SYSERR on error
905 GNUNET_TESTING_connect_topology (struct GNUNET_TESTING_PeerGroup *pg,
906 enum GNUNET_TESTING_Topology topology,
907 enum GNUNET_TESTING_TopologyOption options,
908 double option_modifier,
909 GNUNET_TESTING_NotifyCompletion notify_callback,
913 * Start or stop an individual peer from the given group.
915 * @param pg handle to the peer group
916 * @param offset which peer to start or stop
917 * @param desired_status GNUNET_YES to have it running, GNUNET_NO to stop it
918 * @param timeout how long to wait for shutdown
919 * @param cb function to call at the end
920 * @param cb_cls closure for cb
923 GNUNET_TESTING_daemons_vary (struct GNUNET_TESTING_PeerGroup *pg,
926 struct GNUNET_TIME_Relative timeout,
927 GNUNET_TESTING_NotifyCompletion cb,
931 #if 0 /* keep Emacsens' auto-indent happy */