Imported Upstream version 0.9.2upstream/0.9.2

1 files changed, 1231 insertions, 0 deletions

diff --git a/src/include/gnunet_testing_lib.h b/src/include/gnunet_testing_lib.h
new file mode 100644
index 0000000..03b8376
--- /dev/null
+++ b/src/include/gnunet_testing_lib.h
@@ -0,0 +1,1231 @@
+/*
+      This file is part of GNUnet
+      (C) 2008, 2009 Christian Grothoff (and other contributing authors)
+
+      GNUnet is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published
+      by the Free Software Foundation; either version 3, or (at your
+      option) any later version.
+
+      GNUnet is distributed in the hope that it will be useful, but
+      WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+      General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with GNUnet; see the file COPYING.  If not, write to the
+      Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+      Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * @file include/gnunet_testing_lib.h
+ * @brief convenience API for writing testcases for GNUnet
+ *        Many testcases need to start and stop gnunetd,
+ *        and this library is supposed to make that easier
+ *        for TESTCASES.  Normal programs should always
+ *        use functions from gnunet_{util,arm}_lib.h.  This API is
+ *        ONLY for writing testcases!
+ * @author Christian Grothoff
+ */
+
+#ifndef GNUNET_TESTING_LIB_H
+#define GNUNET_TESTING_LIB_H
+
+#include "gnunet_util_lib.h"
+#include "gnunet_statistics_service.h"
+
+#ifdef __cplusplus
+extern "C"
+{
+#if 0                           /* keep Emacsens' auto-indent happy */
+}
+#endif
+#endif
+
+#define HOSTKEYFILESIZE 914
+
+/**
+ * Handle for a GNUnet daemon (technically a set of
+ * daemons; the handle is really for the master ARM
+ * daemon) started by the testing library.
+ */
+struct GNUNET_TESTING_Daemon;
+
+/**
+ * Linked list of hostnames and ports to use for starting daemons.
+ */
+struct GNUNET_TESTING_Host
+{
+  /**
+   * Pointer to next item in the list.
+   */
+  struct GNUNET_TESTING_Host *next;
+
+  /**
+   * Hostname to connect to.
+   */
+  char *hostname;
+
+  /**
+   * Username to use when connecting (may be null).
+   */
+  char *username;
+
+  /**
+   * Port to use for SSH connection (used for ssh
+   * connection forwarding, 0 to let ssh decide)
+   */
+  uint16_t port;
+};
+
+/**
+ * Prototype of a function that will be called whenever
+ * a daemon was started by the testing library.
+ *
+ * @param cls closure
+ * @param id identifier for the daemon, NULL on error
+ * @param d handle for the daemon
+ * @param emsg error message (NULL on success)
+ */
+typedef void (*GNUNET_TESTING_NotifyHostkeyCreated) (void *cls,
+                                                     const struct
+                                                     GNUNET_PeerIdentity * id,
+                                                     struct
+                                                     GNUNET_TESTING_Daemon * d,
+                                                     const char *emsg);
+
+/**
+ * Prototype of a function that will be called whenever
+ * a daemon was started by the testing library.
+ *
+ * @param cls closure
+ * @param id identifier for the daemon, NULL on error
+ * @param cfg configuration used by this daemon
+ * @param d handle for the daemon
+ * @param emsg error message (NULL on success)
+ */
+typedef void (*GNUNET_TESTING_NotifyDaemonRunning) (void *cls,
+                                                    const struct
+                                                    GNUNET_PeerIdentity * id,
+                                                    const struct
+                                                    GNUNET_CONFIGURATION_Handle
+                                                    * cfg,
+                                                    struct GNUNET_TESTING_Daemon
+                                                    * d, const char *emsg);
+
+/**
+ * Handle to an entire testbed of GNUnet peers.
+ */
+struct GNUNET_TESTING_Testbed;
+
+/**
+ * Phases of starting GNUnet on a system.
+ */
+enum GNUNET_TESTING_StartPhase
+{
+  /**
+   * Copy the configuration file to the target system.
+   */
+  SP_COPYING,
+
+  /**
+   * Configuration file has been copied, generate hostkey.
+   */
+  SP_COPIED,
+
+  /**
+   * Create the hostkey for the peer.
+   */
+  SP_HOSTKEY_CREATE,
+
+  /**
+   * Hostkey generated, wait for topology to be finished.
+   */
+  SP_HOSTKEY_CREATED,
+
+  /**
+   * Topology has been created, now start ARM.
+   */
+  SP_TOPOLOGY_SETUP,
+
+  /**
+   * ARM has been started, check that it has properly daemonized and
+   * then try to connect to the CORE service (which should be
+   * auto-started by ARM).
+   */
+  SP_START_ARMING,
+
+  /**
+   * We're waiting for CORE to start.
+   */
+  SP_START_CORE,
+
+  /**
+   * CORE is up, now make sure we get the HELLO for this peer.
+   */
+  SP_GET_HELLO,
+
+  /**
+   * Core has notified us that we've established a connection to the service.
+   * The main FSM halts here and waits to be moved to UPDATE or CLEANUP.
+   */
+  SP_START_DONE,
+
+  /**
+   * We've been asked to terminate the instance and are now waiting for
+   * the remote command to stop the gnunet-arm process and delete temporary
+   * files.
+   */
+  SP_SHUTDOWN_START,
+
+  /**
+   * We should shutdown a *single* service via gnunet-arm.  Call the dead_cb
+   * upon notification from gnunet-arm that the service has been stopped.
+   */
+  SP_SERVICE_SHUTDOWN_START,
+
+  /**
+   * We should start a *single* service via gnunet-arm.  Call the daemon cb
+   * upon notification from gnunet-arm that the service has been started.
+   */
+  SP_SERVICE_START,
+
+  /**
+   * We've received a configuration update and are currently waiting for
+   * the copy process for the update to complete.  Once it is, we will
+   * return to "SP_START_DONE" (and rely on ARM to restart all affected
+   * services).
+   */
+  SP_CONFIG_UPDATE
+};
+
+/**
+ * Prototype of a function that will be called when a
+ * particular operation was completed the testing library.
+ *
+ * @param cls closure
+ * @param emsg NULL on success
+ */
+typedef void (*GNUNET_TESTING_NotifyCompletion) (void *cls, const char *emsg);
+
+/**
+ * Prototype of a function that will be called with the
+ * number of connections created for a particular topology.
+ *
+ * @param cls closure
+ * @param num_connections the number of connections created
+ */
+typedef void (*GNUNET_TESTING_NotifyConnections) (void *cls,
+                                                  unsigned int num_connections);
+
+/**
+ * Handle for a GNUnet daemon (technically a set of
+ * daemons; the handle is really for the master ARM
+ * daemon) started by the testing library.
+ */
+struct GNUNET_TESTING_Daemon
+{
+  /**
+   * Our configuration.
+   */
+  struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * At what time to give up starting the peer
+   */
+  struct GNUNET_TIME_Absolute max_timeout;
+
+  /**
+   * Host to run GNUnet on.
+   */
+  char *hostname;
+
+  /**
+   * Port to use for ssh, NULL to let system choose default.
+   */
+  char *ssh_port_str;
+
+  /**
+   * Result of GNUNET_i2s of this peer,
+   * for printing
+   */
+  char *shortname;
+
+  /**
+   * Username we are using.
+   */
+  char *username;
+
+  /**
+   * Name of the configuration file
+   */
+  char *cfgfile;
+
+  /**
+   * Callback to inform initiator that the peer's
+   * hostkey has been created.
+   */
+  GNUNET_TESTING_NotifyHostkeyCreated hostkey_callback;
+
+  /**
+   * Closure for hostkey creation callback.
+   */
+  void *hostkey_cls;
+
+  /**
+   * Function to call when the peer is running.
+   */
+  GNUNET_TESTING_NotifyDaemonRunning cb;
+
+  /**
+   * Closure for cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Arguments from "daemon_stop" call.
+   */
+  GNUNET_TESTING_NotifyCompletion dead_cb;
+
+  /**
+   * Closure for 'dead_cb'.
+   */
+  void *dead_cb_cls;
+
+  /**
+   * Arguments from "daemon_stop" call.
+   */
+  GNUNET_TESTING_NotifyCompletion update_cb;
+
+  /**
+   * Closure for 'update_cb'.
+   */
+  void *update_cb_cls;
+
+  /**
+   * PID of the process that we started last.
+   */
+  struct GNUNET_OS_Process *proc;
+
+  /**
+   * Handle to the server.
+   */
+  struct GNUNET_CORE_Handle *server;
+
+  /**
+   * Handle to the transport service of this peer
+   */
+  struct GNUNET_TRANSPORT_Handle *th;
+
+  /**
+   * Handle for getting HELLOs from transport
+   */
+  struct GNUNET_TRANSPORT_GetHelloHandle *ghh;
+
+  /**
+   * HELLO message for this peer
+   */
+  struct GNUNET_HELLO_Message *hello;
+
+  /**
+   * Handle to a pipe for reading the hostkey.
+   */
+  struct GNUNET_DISK_PipeHandle *pipe_stdout;
+
+  /**
+   * Currently, a single char * pointing to a service
+   * that has been churned off.
+   *
+   * FIXME: make this a linked list of services that have been churned off!!!
+   */
+  char *churned_services;
+
+  /**
+   * ID of the current task.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier task;
+
+  /**
+   * Identity of this peer (once started).
+   */
+  struct GNUNET_PeerIdentity id;
+
+  /**
+   * Flag to indicate that we've already been asked
+   * to terminate (but could not because some action
+   * was still pending).
+   */
+  int dead;
+
+  /**
+   * GNUNET_YES if the hostkey has been created
+   * for this peer, GNUNET_NO otherwise.
+   */
+  int have_hostkey;
+
+  /**
+   * In which phase are we during the start of
+   * this process?
+   */
+  enum GNUNET_TESTING_StartPhase phase;
+
+  /**
+   * Current position in 'hostkeybuf' (for reading from gnunet-peerinfo)
+   */
+  unsigned int hostkeybufpos;
+
+  /**
+   * Set to GNUNET_YES once the peer is up.
+   */
+  int running;
+
+  /**
+   * Used to tell shutdown not to remove configuration for the peer
+   * (if it's going to be restarted later)
+   */
+  int churn;
+
+  /**
+   * Output from gnunet-peerinfo is read into this buffer.
+   */
+  char hostkeybuf[105];
+
+};
+
+
+/**
+ * Handle to a group of GNUnet peers.
+ */
+struct GNUNET_TESTING_PeerGroup;
+
+
+/**
+ * Prototype of a function that will be called whenever
+ * two daemons are connected by the testing library.
+ *
+ * @param cls closure
+ * @param first peer id for first daemon
+ * @param second peer id for the second daemon
+ * @param distance distance between the connected peers
+ * @param first_cfg config for the first daemon
+ * @param second_cfg config for the second daemon
+ * @param first_daemon handle for the first daemon
+ * @param second_daemon handle for the second daemon
+ * @param emsg error message (NULL on success)
+ */
+typedef void (*GNUNET_TESTING_NotifyConnection) (void *cls,
+                                                 const struct
+                                                 GNUNET_PeerIdentity * first,
+                                                 const struct
+                                                 GNUNET_PeerIdentity * second,
+                                                 uint32_t distance,
+                                                 const struct
+                                                 GNUNET_CONFIGURATION_Handle *
+                                                 first_cfg,
+                                                 const struct
+                                                 GNUNET_CONFIGURATION_Handle *
+                                                 second_cfg,
+                                                 struct GNUNET_TESTING_Daemon *
+                                                 first_daemon,
+                                                 struct GNUNET_TESTING_Daemon *
+                                                 second_daemon,
+                                                 const char *emsg);
+
+
+/**
+ * Prototype of a callback function indicating that two peers
+ * are currently connected.
+ *
+ * @param cls closure
+ * @param first peer id for first daemon
+ * @param second peer id for the second daemon
+ * @param distance distance between the connected peers
+ * @param emsg error message (NULL on success)
+ */
+typedef void (*GNUNET_TESTING_NotifyTopology) (void *cls,
+                                               const struct GNUNET_PeerIdentity
+                                               * first,
+                                               const struct GNUNET_PeerIdentity
+                                               * second, const char *emsg);
+
+
+/**
+ * Starts a GNUnet daemon.  GNUnet must be installed on the target
+ * system and available in the PATH.  The machine must furthermore be
+ * reachable via "ssh" (unless the hostname is "NULL") without the
+ * need to enter a password.
+ *
+ * @param cfg configuration to use
+ * @param timeout how long to wait starting up peers
+ * @param pretend GNUNET_YES to set up files but not start peer GNUNET_NO
+ *                to really start the peer (default)
+ * @param hostname name of the machine where to run GNUnet
+ *        (use NULL for localhost).
+ * @param ssh_username ssh username to use when connecting to hostname
+ * @param sshport port to pass to ssh process when connecting to hostname
+ * @param hostkey pointer to a hostkey to be written to disk (instead of being generated)
+ * @param hostkey_callback function to call once the hostkey has been
+ *        generated for this peer, but it hasn't yet been started
+ *        (NULL to start immediately, otherwise waits on GNUNET_TESTING_daemon_continue_start)
+ * @param hostkey_cls closure for hostkey callback
+ * @param cb function to call once peer is up, or failed to start
+ * @param cb_cls closure for cb
+ * @return handle to the daemon (actual start will be completed asynchronously)
+ */
+struct GNUNET_TESTING_Daemon *
+GNUNET_TESTING_daemon_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                             struct GNUNET_TIME_Relative timeout, int pretend,
+                             const char *hostname, const char *ssh_username,
+                             uint16_t sshport, const char *hostkey,
+                             GNUNET_TESTING_NotifyHostkeyCreated
+                             hostkey_callback, void *hostkey_cls,
+                             GNUNET_TESTING_NotifyDaemonRunning cb,
+                             void *cb_cls);
+
+/**
+ * Continues GNUnet daemon startup when user wanted to be notified
+ * once a hostkey was generated (for creating friends files, blacklists,
+ * etc.).
+ *
+ * @param daemon the daemon to finish starting
+ */
+void
+GNUNET_TESTING_daemon_continue_startup (struct GNUNET_TESTING_Daemon *daemon);
+
+
+/**
+ * Check whether the given daemon is running.
+ *
+ * @param daemon the daemon to check
+ * @return GNUNET_YES if the daemon is up, GNUNET_NO if the
+ *         daemon is down, GNUNET_SYSERR on error.
+ */
+int
+GNUNET_TESTING_test_daemon_running (struct GNUNET_TESTING_Daemon *daemon);
+
+
+/**
+ * Obtain the peer identity of the peer with the given configuration
+ * handle.  This function reads the private key of the peer, obtains
+ * the public key and hashes it.
+ *
+ * @param cfg configuration of the peer
+ * @param pid where to store the peer identity
+ * @return GNUNET_OK on success, GNUNET_SYSERR on failure
+ */
+int
+GNUNET_TESTING_get_peer_identity (const struct GNUNET_CONFIGURATION_Handle *cfg,
+				  struct GNUNET_PeerIdentity *pid);
+
+
+/**
+ * Restart (stop and start) a GNUnet daemon.
+ *
+ * @param d the daemon that should be restarted
+ * @param cb function called once the daemon is (re)started
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemon_restart (struct GNUNET_TESTING_Daemon *d,
+                               GNUNET_TESTING_NotifyDaemonRunning cb,
+                               void *cb_cls);
+
+
+/**
+ * Start a peer that has previously been stopped using the daemon_stop
+ * call (and files weren't deleted and the allow restart flag)
+ *
+ * @param daemon the daemon to start (has been previously stopped)
+ * @param timeout how long to wait for restart
+ * @param cb the callback for notification when the peer is running
+ * @param cb_cls closure for the callback
+ */
+void
+GNUNET_TESTING_daemon_start_stopped (struct GNUNET_TESTING_Daemon *daemon,
+                                     struct GNUNET_TIME_Relative timeout,
+                                     GNUNET_TESTING_NotifyDaemonRunning cb,
+                                     void *cb_cls);
+
+
+/**
+ * Starts a GNUnet daemon's service.
+ *
+ * @param d the daemon for which the service should be started
+ * @param service the name of the service to start
+ * @param timeout how long to wait for process for startup
+ * @param cb function called once gnunet-arm returns
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemon_start_service (struct GNUNET_TESTING_Daemon *d,
+                                     const char *service,
+                                     struct GNUNET_TIME_Relative timeout,
+                                     GNUNET_TESTING_NotifyDaemonRunning cb,
+                                     void *cb_cls);
+
+
+/**
+ * Starts a GNUnet daemon's service which has been previously turned off.
+ *
+ * @param d the daemon for which the service should be started
+ * @param service the name of the service to start
+ * @param timeout how long to wait for process for startup
+ * @param cb function called once gnunet-arm returns
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemon_start_stopped_service (struct GNUNET_TESTING_Daemon *d,
+                                             char *service,
+                                             struct GNUNET_TIME_Relative
+                                             timeout,
+                                             GNUNET_TESTING_NotifyDaemonRunning
+                                             cb, void *cb_cls);
+
+
+/**
+ * Get a certain testing daemon handle.
+ *
+ * @param pg handle to the set of running peers
+ * @param position the number of the peer to return
+ */
+struct GNUNET_TESTING_Daemon *
+GNUNET_TESTING_daemon_get (struct GNUNET_TESTING_PeerGroup *pg,
+                           unsigned int position);
+
+
+/**
+ * Get a daemon by peer identity, so callers can
+ * retrieve the daemon without knowing it's offset.
+ *
+ * @param pg the peer group to retrieve the daemon from
+ * @param peer_id the peer identity of the daemon to retrieve
+ *
+ * @return the daemon on success, or NULL if no such peer identity is found
+ */
+struct GNUNET_TESTING_Daemon *
+GNUNET_TESTING_daemon_get_by_id (struct GNUNET_TESTING_PeerGroup *pg,
+                                 const struct GNUNET_PeerIdentity *peer_id);
+
+
+/**
+ * Stops a GNUnet daemon.
+ *
+ * @param d the daemon that should be stopped
+ * @param timeout how long to wait for process for shutdown to complete
+ * @param cb function called once the daemon was stopped
+ * @param cb_cls closure for cb
+ * @param delete_files GNUNET_YES to remove files, GNUNET_NO
+ *        to leave them (i.e. for restarting at a later time,
+ *        or logfile inspection once finished)
+ * @param allow_restart GNUNET_YES to restart peer later (using this API)
+ *        GNUNET_NO to kill off and clean up for good
+ */
+void
+GNUNET_TESTING_daemon_stop (struct GNUNET_TESTING_Daemon *d,
+                            struct GNUNET_TIME_Relative timeout,
+                            GNUNET_TESTING_NotifyCompletion cb, void *cb_cls,
+                            int delete_files, int allow_restart);
+
+
+
+/**
+ * Create a new configuration using the given configuration
+ * as a template; however, each PORT in the existing cfg
+ * must be renumbered by incrementing "*port".  If we run
+ * out of "*port" numbers, return NULL.
+ *
+ * @param cfg template configuration
+ * @param off the current peer offset
+ * @param port port numbers to use, update to reflect
+ *             port numbers that were used
+ * @param upnum number to make unix domain socket names unique
+ * @param hostname hostname of the controlling host, to allow control connections from
+ * @param fdnum number used to offset the unix domain socket for grouped processes
+ *              (such as statistics or peerinfo, which can be shared among others)
+ *
+ * @return new configuration, NULL on error
+ */
+struct GNUNET_CONFIGURATION_Handle *
+GNUNET_TESTING_create_cfg (const struct GNUNET_CONFIGURATION_Handle *cfg, uint32_t off,
+             uint16_t * port, uint32_t * upnum, const char *hostname,
+             uint32_t * fdnum);
+
+/**
+ * Changes the configuration of a GNUnet daemon.
+ *
+ * @param d the daemon that should be modified
+ * @param cfg the new configuration for the daemon
+ * @param cb function called once the configuration was changed
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemon_reconfigure (struct GNUNET_TESTING_Daemon *d,
+                                   struct GNUNET_CONFIGURATION_Handle *cfg,
+                                   GNUNET_TESTING_NotifyCompletion cb,
+                                   void *cb_cls);
+
+
+/**
+ * Stops a single service of a GNUnet daemon.  Used like daemon_stop,
+ * only doesn't stop the entire peer in any case.  If the service
+ * is not currently running, this call is likely to fail after
+ * timeout!
+ *
+ * @param d the daemon that should be stopped
+ * @param service the name of the service to stop
+ * @param timeout how long to wait for process for shutdown to complete
+ * @param cb function called once the service was stopped
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemon_stop_service (struct GNUNET_TESTING_Daemon *d,
+                                    const char *service,
+                                    struct GNUNET_TIME_Relative timeout,
+                                    GNUNET_TESTING_NotifyCompletion cb,
+                                    void *cb_cls);
+
+
+/**
+ * Read a testing hosts file based on a configuration.
+ * Returns a DLL of hosts (caller must free!) on success
+ * or NULL on failure.
+ *
+ * @param cfg a configuration with a testing section
+ *
+ * @return DLL of hosts on success, NULL on failure
+ */
+struct GNUNET_TESTING_Host *
+GNUNET_TESTING_hosts_load (const struct GNUNET_CONFIGURATION_Handle *cfg);
+
+
+/**
+ * Start count gnunet instances with the same set of transports and
+ * applications.  The port numbers (any option called "PORT") will be
+ * adjusted to ensure that no two peers running on the same system
+ * have the same port(s) in their respective configurations.
+ *
+ * @param cfg configuration template to use
+ * @param total number of daemons to start
+ * @param max_concurrent_connections for testing, how many peers can
+*                                   we connect to simultaneously
+ * @param max_concurrent_ssh when starting with ssh, how many ssh
+ *        connections will we allow at once (based on remote hosts allowed!)
+ * @param timeout total time allowed for peers to start
+ * @param hostkey_callback function to call on each peers hostkey generation
+ *        if NULL, peers will be started by this call, if non-null,
+ *        GNUNET_TESTING_daemons_continue_startup must be called after
+ *        successful hostkey generation
+ * @param hostkey_cls closure for hostkey callback
+ * @param cb function to call on each daemon that was started
+ * @param cb_cls closure for cb
+ * @param connect_callback function to call each time two hosts are connected
+ * @param connect_callback_cls closure for connect_callback
+ * @param hostnames linked list of host structs to use to start peers on
+ *                  (NULL to run on localhost only)
+ *
+ * @return NULL on error, otherwise handle to control peer group
+ */
+struct GNUNET_TESTING_PeerGroup *
+GNUNET_TESTING_daemons_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                              unsigned int total,
+                              unsigned int max_concurrent_connections,
+                              unsigned int max_concurrent_ssh,
+                              struct GNUNET_TIME_Relative timeout,
+                              GNUNET_TESTING_NotifyHostkeyCreated
+                              hostkey_callback, void *hostkey_cls,
+                              GNUNET_TESTING_NotifyDaemonRunning cb,
+                              void *cb_cls,
+                              GNUNET_TESTING_NotifyConnection connect_callback,
+                              void *connect_callback_cls,
+                              const struct GNUNET_TESTING_Host *hostnames);
+
+
+/**
+ * Function which continues a peer group starting up
+ * after successfully generating hostkeys for each peer.
+ *
+ * @param pg the peer group to continue starting
+ */
+void
+GNUNET_TESTING_daemons_continue_startup (struct GNUNET_TESTING_PeerGroup *pg);
+
+
+/**
+ * Handle for an active request to connect two peers.
+ */
+struct GNUNET_TESTING_ConnectContext;
+
+
+/**
+ * Establish a connection between two GNUnet daemons.  The daemons
+ * must both be running and not be stopped until either the
+ * 'cb' callback is called OR the connection request has been
+ * explicitly cancelled.
+ *
+ * @param d1 handle for the first daemon
+ * @param d2 handle for the second daemon
+ * @param timeout how long is the connection attempt
+ *        allowed to take?
+ * @param max_connect_attempts how many times should we try to reconnect
+ *        (within timeout)
+ * @param send_hello GNUNET_YES to send the HELLO, GNUNET_NO to assume
+ *                   the HELLO has already been exchanged
+ * @param cb function to call at the end
+ * @param cb_cls closure for cb
+ * @return handle to cancel the request, NULL on error
+ */
+struct GNUNET_TESTING_ConnectContext *
+GNUNET_TESTING_daemons_connect (struct GNUNET_TESTING_Daemon *d1,
+                                struct GNUNET_TESTING_Daemon *d2,
+                                struct GNUNET_TIME_Relative timeout,
+                                unsigned int max_connect_attempts,
+                                int send_hello,
+                                GNUNET_TESTING_NotifyConnection cb,
+                                void *cb_cls);
+
+
+
+/**
+ * Cancel an attempt to connect two daemons.
+ *
+ * @param cc connect context
+ */
+void
+GNUNET_TESTING_daemons_connect_cancel (struct GNUNET_TESTING_ConnectContext
+                                       *cc);
+
+
+
+/**
+ * Restart all peers in the given group.
+ *
+ * @param pg the handle to the peer group
+ * @param callback function to call on completion (or failure)
+ * @param callback_cls closure for the callback function
+ */
+void
+GNUNET_TESTING_daemons_restart (struct GNUNET_TESTING_PeerGroup *pg,
+                                GNUNET_TESTING_NotifyCompletion callback,
+                                void *callback_cls);
+
+
+/**
+ * Shutdown all peers started in the given group.
+ *
+ * @param pg handle to the peer group
+ * @param timeout how long to wait for shutdown
+ * @param cb callback to notify upon success or failure
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemons_stop (struct GNUNET_TESTING_PeerGroup *pg,
+                             struct GNUNET_TIME_Relative timeout,
+                             GNUNET_TESTING_NotifyCompletion cb, void *cb_cls);
+
+
+/**
+ * Count the number of running peers.
+ *
+ * @param pg handle for the peer group
+ *
+ * @return the number of currently running peers in the peer group
+ */
+unsigned int
+GNUNET_TESTING_daemons_running (struct GNUNET_TESTING_PeerGroup *pg);
+
+
+/**
+ * Simulate churn by stopping some peers (and possibly
+ * re-starting others if churn is called multiple times).  This
+ * function can only be used to create leave-join churn (peers "never"
+ * leave for good).  First "voff" random peers that are currently
+ * online will be taken offline; then "von" random peers that are then
+ * offline will be put back online.  No notifications will be
+ * generated for any of these operations except for the callback upon
+ * completion.  Note that the implementation is at liberty to keep
+ * the ARM service itself (but none of the other services or daemons)
+ * running even though the "peer" is being varied offline.
+ *
+ * @param pg handle for the peer group
+ * @param service the service to churn on/off, NULL for all
+ * @param voff number of peers that should go offline
+ * @param von number of peers that should come back online;
+ *            must be zero on first call (since "testbed_start"
+ *            always starts all of the peers)
+ * @param timeout how long to wait for operations to finish before
+ *        giving up
+ * @param cb function to call at the end
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemons_churn (struct GNUNET_TESTING_PeerGroup *pg,
+                              char *service, unsigned int voff,
+                              unsigned int von,
+                              struct GNUNET_TIME_Relative timeout,
+                              GNUNET_TESTING_NotifyCompletion cb, void *cb_cls);
+
+
+/**
+ * Start a given service for each of the peers in the peer group.
+ *
+ * @param pg handle for the peer group
+ * @param service the service to start
+ * @param timeout how long to wait for operations to finish before
+ *        giving up
+ * @param cb function to call once finished
+ * @param cb_cls closure for cb
+ *
+ */
+void
+GNUNET_TESTING_daemons_start_service (struct GNUNET_TESTING_PeerGroup *pg,
+                                      char *service,
+                                      struct GNUNET_TIME_Relative timeout,
+                                      GNUNET_TESTING_NotifyCompletion cb,
+                                      void *cb_cls);
+
+
+/**
+ * Callback function to process statistic values.
+ *
+ * @param cls closure
+ * @param peer the peer the statistics belong to
+ * @param subsystem name of subsystem that created the statistic
+ * @param name the name of the datum
+ * @param value the current value
+ * @param is_persistent GNUNET_YES if the value is persistent, GNUNET_NO if not
+ * @return GNUNET_OK to continue, GNUNET_SYSERR to abort iteration
+ */
+typedef int (*GNUNET_TESTING_STATISTICS_Iterator) (void *cls,
+                                                   const struct
+                                                   GNUNET_PeerIdentity * peer,
+                                                   const char *subsystem,
+                                                   const char *name,
+                                                   uint64_t value,
+                                                   int is_persistent);
+
+
+/**
+ * Iterate over all (running) peers in the peer group, retrieve
+ * all statistics from each.
+ *
+ * @param pg the peergroup to iterate statistics of
+ * @param cont continuation to call once call is completed(?)
+ * @param proc processing function for each statistic retrieved
+ * @param cls closure to pass to proc
+ */
+void
+GNUNET_TESTING_get_statistics (struct GNUNET_TESTING_PeerGroup *pg,
+                               GNUNET_STATISTICS_Callback cont,
+                               GNUNET_TESTING_STATISTICS_Iterator proc,
+                               void *cls);
+
+
+/**
+ * Topologies supported for testbeds.
+ */
+enum GNUNET_TESTING_Topology
+{
+  /**
+   * A clique (everyone connected to everyone else).
+   */
+  GNUNET_TESTING_TOPOLOGY_CLIQUE,
+
+  /**
+   * Small-world network (2d torus plus random links).
+   */
+  GNUNET_TESTING_TOPOLOGY_SMALL_WORLD,
+
+  /**
+   * Small-world network (ring plus random links).
+   */
+  GNUNET_TESTING_TOPOLOGY_SMALL_WORLD_RING,
+
+  /**
+   * Ring topology.
+   */
+  GNUNET_TESTING_TOPOLOGY_RING,
+
+  /**
+   * 2-d torus.
+   */
+  GNUNET_TESTING_TOPOLOGY_2D_TORUS,
+
+  /**
+   * Random graph.
+   */
+  GNUNET_TESTING_TOPOLOGY_ERDOS_RENYI,
+
+  /**
+   * Certain percentage of peers are unable to communicate directly
+   * replicating NAT conditions
+   */
+  GNUNET_TESTING_TOPOLOGY_INTERNAT,
+
+  /**
+   * Scale free topology.
+   */
+  GNUNET_TESTING_TOPOLOGY_SCALE_FREE,
+
+  /**
+   * Straight line topology.
+   */
+  GNUNET_TESTING_TOPOLOGY_LINE,
+
+  /**
+   * All peers are disconnected.
+   */
+  GNUNET_TESTING_TOPOLOGY_NONE,
+
+  /**
+   * Read a topology from a given file.
+   */
+  GNUNET_TESTING_TOPOLOGY_FROM_FILE
+};
+
+/**
+ * Options for connecting a topology.
+ */
+enum GNUNET_TESTING_TopologyOption
+{
+  /**
+   * Try to connect all peers specified in the topology.
+   */
+  GNUNET_TESTING_TOPOLOGY_OPTION_ALL,
+
+  /**
+   * Choose a random subset of connections to create.
+   */
+  GNUNET_TESTING_TOPOLOGY_OPTION_RANDOM,
+
+  /**
+   * Create at least X connections for each peer.
+   */
+  GNUNET_TESTING_TOPOLOGY_OPTION_MINIMUM,
+
+  /**
+   * Using a depth first search, create one connection
+   * per peer.  If any are missed (graph disconnected)
+   * start over at those peers until all have at least one
+   * connection.
+   */
+  GNUNET_TESTING_TOPOLOGY_OPTION_DFS,
+
+  /**
+   * Find the N closest peers to each allowed peer in the
+   * topology and make sure a connection to those peers
+   * exists in the connect topology.
+   */
+  GNUNET_TESTING_TOPOLOGY_OPTION_ADD_CLOSEST,
+
+  /**
+   * No options specified.
+   */
+  GNUNET_TESTING_TOPOLOGY_OPTION_NONE
+};
+
+
+/**
+ * Get a topology from a string input.
+ *
+ * @param topology where to write the retrieved topology
+ * @param topology_string The string to attempt to
+ *        get a configuration value from
+ * @return GNUNET_YES if topology string matched a
+ *         known topology, GNUNET_NO if not
+ */
+int
+GNUNET_TESTING_topology_get (enum GNUNET_TESTING_Topology *topology,
+                             const char *topology_string);
+
+
+/**
+ * Get connect topology option from string input.
+ *
+ * @param topology_option where to write the retrieved topology
+ * @param topology_string The string to attempt to
+ *        get a configuration value from
+ * @return GNUNET_YES if topology string matched a
+ *         known topology, GNUNET_NO if not
+ */
+int
+GNUNET_TESTING_topology_option_get (enum GNUNET_TESTING_TopologyOption
+                                    *topology_option,
+                                    const char *topology_string);
+
+
+/**
+ * Takes a peer group and creates a topology based on the
+ * one specified.  Creates a topology means generates friend
+ * files for the peers so they can only connect to those allowed
+ * by the topology.  This will only have an effect once peers
+ * are started if the FRIENDS_ONLY option is set in the base
+ * config.
+ *
+ * Also takes an optional restrict topology which
+ * disallows direct connections UNLESS they are specified in
+ * the restricted topology.
+ *
+ * A simple example; if the topology option is set to LINE
+ * peers can ONLY connect in a LINE.  However, if the topology
+ * option is set to 2D-torus and the restrict option is set to
+ * line with restrict_transports equal to "tcp udp", then peers
+ * may connect in a 2D-torus, but will be restricted to tcp and
+ * udp connections only in a LINE.  Generally it only makes
+ * sense to do this if restrict_topology is a subset of topology.
+ *
+ * For testing peer discovery, etc. it is generally better to
+ * leave restrict_topology as GNUNET_TESTING_TOPOLOGY_NONE and
+ * then use the connect_topology function to restrict the initial
+ * connection set.
+ *
+ * @param pg the peer group struct representing the running peers
+ * @param topology which topology to connect the peers in
+ * @param restrict_topology allow only direct connections in this topology,
+ *        based on those listed in restrict_transports, set to
+ *        GNUNET_TESTING_TOPOLOGY_NONE for no restrictions
+ * @param restrict_transports space delimited list of transports to blacklist
+ *                            to create restricted topology, NULL for none
+ *
+ * @return the maximum number of connections were all allowed peers
+ *         connected to each other
+ */
+unsigned int
+GNUNET_TESTING_create_topology (struct GNUNET_TESTING_PeerGroup *pg,
+                                enum GNUNET_TESTING_Topology topology,
+                                enum GNUNET_TESTING_Topology restrict_topology,
+                                const char *restrict_transports);
+
+
+/**
+ * Iterate over all (running) peers in the peer group, retrieve
+ * all connections that each currently has.
+ *
+ * @param pg the peer group we are concerned with
+ * @param cb callback for topology information
+ * @param cls closure for callback
+ */
+void
+GNUNET_TESTING_get_topology (struct GNUNET_TESTING_PeerGroup *pg,
+                             GNUNET_TESTING_NotifyTopology cb, void *cls);
+
+
+/**
+ * Stop the connection process temporarily.
+ *
+ * @param pg the peer group to stop connecting
+ */
+void
+GNUNET_TESTING_stop_connections (struct GNUNET_TESTING_PeerGroup *pg);
+
+
+/**
+ * Resume the connection process.
+ *
+ * @param pg the peer group to resume connecting
+ */
+void
+GNUNET_TESTING_resume_connections (struct GNUNET_TESTING_PeerGroup *pg);
+
+
+/**
+ * There are many ways to connect peers that are supported by this function.
+ * To connect peers in the same topology that was created via the
+ * GNUNET_TESTING_create_topology, the topology variable must be set to
+ * GNUNET_TESTING_TOPOLOGY_NONE.  If the topology variable is specified,
+ * a new instance of that topology will be generated and attempted to be
+ * connected.  This could result in some connections being impossible,
+ * because some topologies are non-deterministic.
+ *
+ * @param pg the peer group struct representing the running peers
+ * @param topology which topology to connect the peers in
+ * @param options options for connecting the topology
+ * @param option_modifier modifier for options that take a parameter
+ * @param connect_timeout how long to wait before giving up on connecting
+ *                        two peers
+ * @param connect_attempts how many times to attempt to connect two peers
+ *                         over the connect_timeout duration
+ * @param notify_callback notification to be called once all connections completed
+ * @param notify_cls closure for notification callback
+ *
+ * @return the number of connections that will be attempted, GNUNET_SYSERR on error
+ */
+int
+GNUNET_TESTING_connect_topology (struct GNUNET_TESTING_PeerGroup *pg,
+                                 enum GNUNET_TESTING_Topology topology,
+                                 enum GNUNET_TESTING_TopologyOption options,
+                                 double option_modifier,
+                                 struct GNUNET_TIME_Relative connect_timeout,
+                                 unsigned int connect_attempts,
+                                 GNUNET_TESTING_NotifyCompletion
+                                 notify_callback, void *notify_cls);
+
+
+/**
+ * Start or stop an individual peer from the given group.
+ *
+ * @param pg handle to the peer group
+ * @param offset which peer to start or stop
+ * @param desired_status GNUNET_YES to have it running, GNUNET_NO to stop it
+ * @param timeout how long to wait for shutdown
+ * @param cb function to call at the end
+ * @param cb_cls closure for cb
+ */
+void
+GNUNET_TESTING_daemons_vary (struct GNUNET_TESTING_PeerGroup *pg,
+                             unsigned int offset, int desired_status,
+                             struct GNUNET_TIME_Relative timeout,
+                             GNUNET_TESTING_NotifyCompletion cb, void *cb_cls);
+
+
+/**
+ * Start a peer group with a given number of peers.  Notify
+ * on completion of peer startup and connection based on given
+ * topological constraints.  Optionally notify on each
+ * established connection.
+ *
+ * @param cfg configuration template to use
+ * @param total number of daemons to start
+ * @param timeout total time allowed for peers to start
+ * @param connect_cb function to call each time two daemons are connected
+ * @param peergroup_cb function to call once all peers are up and connected
+ * @param peergroup_cls closure for peergroup callbacks
+ * @param hostnames linked list of host structs to use to start peers on
+ *                  (NULL to run on localhost only)
+ *
+ * @return NULL on error, otherwise handle to control peer group
+ */
+struct GNUNET_TESTING_PeerGroup *
+GNUNET_TESTING_peergroup_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                                unsigned int total,
+                                struct GNUNET_TIME_Relative timeout,
+                                GNUNET_TESTING_NotifyConnection connect_cb,
+                                GNUNET_TESTING_NotifyCompletion peergroup_cb,
+                                void *peergroup_cls,
+                                const struct GNUNET_TESTING_Host *hostnames);
+
+
+/**
+ * Print current topology to a graphviz readable file.
+ *
+ * @param pg a currently running peergroup to print to file
+ * @param output_filename the file to write the topology to
+ * @param notify_cb callback to call upon completion or failure
+ * @param notify_cb_cls closure for notify_cb
+ *
+ */
+void
+GNUNET_TESTING_peergroup_topology_to_file (struct GNUNET_TESTING_PeerGroup *pg,
+                                           const char *output_filename,
+                                           GNUNET_TESTING_NotifyCompletion
+                                           notify_cb, void *notify_cb_cls);
+
+
+#if 0                           /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+#endif