src/transport/transport_api.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2009 Christian Grothoff (and other contributing authors)
   4
   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.
   9
  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.
  14
  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.
  19 */
  20
  21 /**
  22  * @file transport/transport_api.c
  23  * @brief library to access the low-level P2P IO service
  24  * @author Christian Grothoff
  25  */
  26 #include "platform.h"
  27 #include "gnunet_client_lib.h"
  28 #include "gnunet_arm_service.h"
  29 #include "gnunet_hello_lib.h"
  30 #include "gnunet_protocols.h"
  31 #include "gnunet_server_lib.h"
  32 #include "gnunet_time_lib.h"
  33 #include "gnunet_transport_service.h"
  34 #include "transport.h"
  35
  36 /**
  37  * After how long do we give up on transmitting a HELLO
  38  * to the service?
  39  */
  40 #define OFFER_HELLO_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
  41
  42 /**
  43  * After how long do we automatically retry an unsuccessful
  44  * CONNECT request?
  45  */
  46 #define CONNECT_RETRY_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 750)
  47
  48 /**
  49  * How long should ARM wait when starting up the
  50  * transport service before reporting back?
  51  */
  52 #define START_SERVICE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
  53
  54 /**
  55  * How long should ARM wait when stopping the
  56  * transport service before reporting back?
  57  */
  58 #define STOP_SERVICE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
  59
  60 /**
  61  * Entry in linked list of all of our current neighbours.
  62  */
  63 struct NeighbourList
  64 {
  65
  66   /**
  67    * This is a linked list.
  68    */
  69   struct NeighbourList *next;
  70
  71   /**
  72    * Active transmit handle, can be NULL.  Used to move
  73    * from ready to wait list on disconnect and to block
  74    * two transmissions to the same peer from being scheduled
  75    * at the same time.
  76    */
  77   struct GNUNET_TRANSPORT_TransmitHandle *transmit_handle;
  78
  79   /**
  80    * Identity of this neighbour.
  81    */
  82   struct GNUNET_PeerIdentity id;
  83
  84   /**
  85    * At what time did we reset last_sent last?
  86    */
  87   struct GNUNET_TIME_Absolute last_quota_update;
  88
  89   /**
  90    * How many bytes have we sent since the "last_quota_update"
  91    * timestamp?
  92    */
  93   uint64_t last_sent;
  94
  95   /**
  96    * Quota for outbound traffic to the neighbour in bytes/ms.
  97    */
  98   uint32_t quota_out;
  99
 100   /**
 101    * Set to GNUNET_YES if we are currently allowed to
 102    * transmit a message to the transport service for this
 103    * peer, GNUNET_NO otherwise.
 104    */
 105   int transmit_ok;
 106
 107   /**
 108    * Set to GNUNET_YES if we have received an ACK for the
 109    * given peer.  Peers that receive our HELLO always respond
 110    * with an ACK to let us know that we are successfully
 111    * communicating.  Note that a PING can not be used for this
 112    * since PINGs are only send if a HELLO address requires
 113    * confirmation (and also, PINGs are not passed to the
 114    * transport API itself).
 115    */
 116   int received_ack;
 117
 118 };
 119
 120
 121 /**
 122  * Linked list of requests from clients for our HELLO
 123  * that were deferred.
 124  */
 125 struct HelloWaitList
 126 {
 127
 128   /**
 129    * This is a linked list.
 130    */
 131   struct HelloWaitList *next;
 132
 133   /**
 134    * Reference back to our transport handle.
 135    */
 136   struct GNUNET_TRANSPORT_Handle *handle;
 137
 138   /**
 139    * Callback to call once we got our HELLO.
 140    */
 141   GNUNET_TRANSPORT_HelloUpdateCallback rec;
 142
 143   /**
 144    * Closure for rec.
 145    */
 146   void *rec_cls;
 147
 148   /**
 149    * When to time out (call rec with NULL).
 150    */
 151   struct GNUNET_TIME_Absolute timeout;
 152
 153   /**
 154    * Timeout task (used to trigger timeout,
 155    * cancel if we get the HELLO in time).
 156    */
 157   GNUNET_SCHEDULER_TaskIdentifier task;
 158
 159
 160 };
 161
 162
 163 /**
 164  * Opaque handle for a transmission-ready request.
 165  */
 166 struct GNUNET_TRANSPORT_TransmitHandle
 167 {
 168
 169   /**
 170    * We keep the transmit handles that are waiting for
 171    * a transport-level connection in a doubly linked list.
 172    */
 173   struct GNUNET_TRANSPORT_TransmitHandle *next;
 174
 175   /**
 176    * We keep the transmit handles that are waiting for
 177    * a transport-level connection in a doubly linked list.
 178    */
 179   struct GNUNET_TRANSPORT_TransmitHandle *prev;
 180
 181   /**
 182    * Handle of the main transport data structure.
 183    */
 184   struct GNUNET_TRANSPORT_Handle *handle;
 185
 186   /**
 187    * Neighbour for this handle, can be NULL if the service
 188    * is not yet connected to the target.
 189    */
 190   struct NeighbourList *neighbour;
 191
 192   /**
 193    * Which peer is this transmission going to be for?  All
 194    * zeros if it is control-traffic to the service.
 195    */
 196   struct GNUNET_PeerIdentity target;
 197
 198   /**
 199    * Function to call when notify_size bytes are available
 200    * for transmission.
 201    */
 202   GNUNET_CONNECTION_TransmitReadyNotify notify;
 203
 204   /**
 205    * Closure for notify.
 206    */
 207   void *notify_cls;
 208
 209   /**
 210    * transmit_ready task Id.  The task is used to introduce the
 211    * artificial delay that may be required to maintain the bandwidth
 212    * limits.  Later, this will be the ID of the "transmit_timeout"
 213    * task which is used to signal a timeout if the transmission could
 214    * not be done in a timely fashion.
 215    */
 216   GNUNET_SCHEDULER_TaskIdentifier notify_delay_task;
 217
 218   /**
 219    * Timeout for this request.
 220    */
 221   struct GNUNET_TIME_Absolute timeout;
 222
 223   /**
 224    * How many bytes is our notify callback waiting for?
 225    */
 226   size_t notify_size;
 227
 228   /**
 229    * How important is this message?
 230    */
 231   unsigned int priority;
 232
 233 };
 234
 235
 236 /**
 237  * Handle for the transport service (includes all of the
 238  * state for the transport service).
 239  */
 240 struct GNUNET_TRANSPORT_Handle
 241 {
 242
 243   /**
 244    * Closure for the callbacks.
 245    */
 246   void *cls;
 247
 248   /**
 249    * Function to call for received data.
 250    */
 251   GNUNET_TRANSPORT_ReceiveCallback rec;
 252
 253   /**
 254    * function to call on connect events
 255    */
 256   GNUNET_TRANSPORT_NotifyConnect nc_cb;
 257
 258   /**
 259    * function to call on disconnect events
 260    */
 261   GNUNET_TRANSPORT_NotifyDisconnect nd_cb;
 262
 263   /**
 264    * The current HELLO message for this peer.  Updated
 265    * whenever transports change their addresses.
 266    */
 267   struct GNUNET_HELLO_Message *my_hello;
 268
 269   /**
 270    * My client connection to the transport service.
 271    */
 272   struct GNUNET_CLIENT_Connection *client;
 273
 274   /**
 275    * Handle to our registration with the client for notification.
 276    */
 277   struct GNUNET_CLIENT_TransmitHandle *network_handle;
 278
 279   /**
 280    * Linked list of transmit handles that are waiting for the
 281    * transport to connect to the respective peer.  When we
 282    * receive notification that the transport connected to a
 283    * peer, we go over this list and check if someone has already
 284    * requested a transmission to the new peer; if so, we trigger
 285    * the next step.
 286    */
 287   struct GNUNET_TRANSPORT_TransmitHandle *connect_wait_head;
 288
 289   /**
 290    * Linked list of transmit handles that are waiting for the
 291    * transport to be ready for transmission to the respective
 292    * peer.  When we
 293    * receive notification that the transport disconnected from
 294    * a peer, we go over this list and move the entry back to
 295    * the connect_wait list.
 296    */
 297   struct GNUNET_TRANSPORT_TransmitHandle *connect_ready_head;
 298
 299   /**
 300    * Linked list of pending requests for our HELLO.
 301    */
 302   struct HelloWaitList *hwl_head;
 303
 304   /**
 305    * My scheduler.
 306    */
 307   struct GNUNET_SCHEDULER_Handle *sched;
 308
 309   /**
 310    * My configuration.
 311    */
 312   const struct GNUNET_CONFIGURATION_Handle *cfg;
 313
 314   /**
 315    * Linked list of the current neighbours of this peer.
 316    */
 317   struct NeighbourList *neighbours;
 318
 319   /**
 320    * ID of the task trying to reconnect to the
 321    * service.
 322    */
 323   GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
 324
 325   /**
 326    * Delay until we try to reconnect.
 327    */
 328   struct GNUNET_TIME_Relative reconnect_delay;
 329
 330   /**
 331    * Do we currently have a transmission pending?
 332    * (schedule transmission was called but has not
 333    * yet succeeded)?
 334    */
 335   int transmission_scheduled;
 336 };
 337
 338
 339 static struct NeighbourList *
 340 find_neighbour (struct GNUNET_TRANSPORT_Handle *h,
 341                 const struct GNUNET_PeerIdentity *peer)
 342 {
 343   struct NeighbourList *pos;
 344
 345   pos = h->neighbours;
 346   while ((pos != NULL) &&
 347          (0 != memcmp (peer, &pos->id, sizeof (struct GNUNET_PeerIdentity))))
 348     pos = pos->next;
 349   return pos;
 350 }
 351
 352
 353 /**
 354  * Schedule the task to send one message from the
 355  * connect_ready list to the service.
 356  */
 357 static void schedule_transmission (struct GNUNET_TRANSPORT_Handle *h);
 358
 359
 360 /**
 361  * Transmit message to client...
 362  */
 363 static size_t
 364 transport_notify_ready (void *cls, size_t size, void *buf)
 365 {
 366   struct GNUNET_TRANSPORT_Handle *h = cls;
 367   struct GNUNET_TRANSPORT_TransmitHandle *th;
 368   struct NeighbourList *n;
 369   size_t ret;
 370   char *cbuf;
 371
 372   h->network_handle = NULL;
 373   h->transmission_scheduled = GNUNET_NO;
 374   if (buf == NULL)
 375     {
 376 #if DEBUG_TRANSPORT
 377       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 378                   "Could not transmit to transport service, cancelling pending requests\n");
 379 #endif
 380       th = h->connect_ready_head;
 381       if (th->next != NULL)
 382         th->next->prev = NULL;
 383       h->connect_ready_head = th->next;
 384       if (NULL != (n = th->neighbour))
 385         {
 386           GNUNET_assert (n->transmit_handle == th);
 387           n->transmit_handle = NULL;
 388         }
 389       if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
 390         {
 391           GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task);
 392           th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
 393         }
 394       if (NULL != th->notify)
 395         GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
 396       GNUNET_free (th);
 397       if (h->connect_ready_head != NULL)
 398         schedule_transmission (h);      /* FIXME: is this ok? */
 399       return 0;
 400     }
 401 #if DEBUG_TRANSPORT
 402   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 403               "Ready to transmit %u bytes to transport service\n", size);
 404 #endif
 405   cbuf = buf;
 406   ret = 0;
 407   h->network_handle = NULL;
 408   h->transmission_scheduled = GNUNET_NO;
 409   while ((h->connect_ready_head != NULL) &&
 410          (h->connect_ready_head->notify_size <= size))
 411     {
 412       th = h->connect_ready_head;
 413       if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
 414         {
 415           GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task);
 416           th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
 417         }
 418       GNUNET_assert (th->notify_size <= size);
 419       if (th->next != NULL)
 420         th->next->prev = NULL;
 421       h->connect_ready_head = th->next;
 422       if (NULL != (n = th->neighbour))
 423         {
 424           GNUNET_assert (n->transmit_handle == th);
 425           n->transmit_handle = NULL;
 426         }
 427       if (NULL != th->notify)
 428         ret += th->notify (th->notify_cls, size, &cbuf[ret]);
 429       GNUNET_free (th);
 430       if (n != NULL)
 431         n->last_sent += ret;
 432       size -= ret;
 433     }
 434   if (h->connect_ready_head != NULL)
 435     schedule_transmission (h);
 436 #if DEBUG_TRANSPORT
 437   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 438               "Transmitting %u bytes to transport service\n", ret);
 439 #endif
 440   return ret;
 441 }
 442
 443
 444 /**
 445  * Schedule the task to send one message from the
 446  * connect_ready list to the service.
 447  */
 448 static void
 449 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
 450 {
 451   struct GNUNET_TRANSPORT_TransmitHandle *th;
 452
 453   GNUNET_assert (NULL == h->network_handle);
 454   if (h->client == NULL)
 455     {
 456       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 457                   "Could not yet schedule transmission: we are not yet connected to the transport service!\n");
 458       return;                   /* not yet connected */
 459     }
 460   th = h->connect_ready_head;
 461   if (th == NULL)
 462     return;                     /* no request pending */
 463   if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
 464     {
 465       /* remove existing time out task, will be integrated
 466          with transmit_ready notification! */
 467       GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task);
 468       th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
 469     }
 470   h->transmission_scheduled = GNUNET_YES;
 471   h->network_handle = GNUNET_CLIENT_notify_transmit_ready (h->client,
 472                                                            th->notify_size,
 473                                                            GNUNET_TIME_absolute_get_remaining
 474                                                            (th->timeout),
 475                                                            GNUNET_NO,
 476                                                            &transport_notify_ready,
 477                                                            h);
 478   GNUNET_assert (NULL != h->network_handle);
 479 }
 480
 481
 482 /**
 483  * Insert the given transmit handle in the given sorted
 484  * doubly linked list based on timeout.
 485  *
 486  * @param head pointer to the head of the linked list
 487  * @param th element to insert into the list
 488  */
 489 static void
 490 insert_transmit_handle (struct GNUNET_TRANSPORT_TransmitHandle **head,
 491                         struct GNUNET_TRANSPORT_TransmitHandle *th)
 492 {
 493   struct GNUNET_TRANSPORT_TransmitHandle *pos;
 494   struct GNUNET_TRANSPORT_TransmitHandle *prev;
 495
 496   pos = *head;
 497   prev = NULL;
 498   while ((pos != NULL) && (pos->timeout.value < th->timeout.value))
 499     {
 500       prev = pos;
 501       pos = pos->next;
 502     }
 503   if (prev == NULL)
 504     {
 505       th->next = *head;
 506       if (th->next != NULL)
 507         th->next->prev = th;
 508       *head = th;
 509     }
 510   else
 511     {
 512       th->next = pos;
 513       th->prev = prev;
 514       prev->next = th;
 515       if (pos != NULL)
 516         pos->prev = th;
 517     }
 518 }
 519
 520
 521 /**
 522  * Cancel a pending notify delay task (if pending) and also remove the
 523  * given transmit handle from whatever list is on.
 524  *
 525  * @param th handle for the transmission request to manipulate
 526  */
 527 static void
 528 remove_from_any_list (struct GNUNET_TRANSPORT_TransmitHandle *th)
 529 {
 530   struct GNUNET_TRANSPORT_Handle *h;
 531
 532   h = th->handle;
 533   if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
 534     {
 535       GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task);
 536       th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
 537     }
 538   if (th->prev == NULL)
 539     {
 540       if (th == h->connect_wait_head)
 541         h->connect_wait_head = th->next;
 542       else
 543         h->connect_ready_head = th->next;
 544     }
 545   else
 546     {
 547       th->prev->next = th->next;
 548     }
 549   if (th->next != NULL)
 550     th->next->prev = th->prev;
 551 }
 552
 553
 554 /**
 555  * Schedule a request to connect to the given
 556  * neighbour (and if successful, add the specified
 557  * handle to the wait list).
 558  *
 559  * @param th handle for a request to transmit once we
 560  *        have connected
 561  */
 562 static void try_connect (struct GNUNET_TRANSPORT_TransmitHandle *th);
 563
 564
 565 /**
 566  * Called when our transmit request timed out before any transport
 567  * reported success connecting to the desired peer or before the
 568  * transport was ready to receive.  Signal error and free
 569  * TransmitHandle.
 570  */
 571 static void
 572 peer_transmit_timeout (void *cls,
 573                        const struct GNUNET_SCHEDULER_TaskContext *tc)
 574 {
 575   struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
 576
 577   th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
 578   if (th->neighbour != NULL)
 579     th->neighbour->transmit_handle = NULL;
 580 #if DEBUG_TRANSPORT
 581   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 582               "Request for transmission to peer `%s' timed out.\n",
 583               GNUNET_i2s (&th->target));
 584 #endif
 585   remove_from_any_list (th);
 586   if (NULL != th->notify)
 587     th->notify (th->notify_cls, 0, NULL);
 588   GNUNET_free (th);
 589 }
 590
 591
 592
 593
 594 /**
 595  * Queue control request for transmission to the transport
 596  * service.
 597  *
 598  * @param h handle to the transport service
 599  * @param size number of bytes to be transmitted
 600  * @param at_head request must be added to the head of the queue
 601  *        (otherwise request will be appended)
 602  * @param timeout how long this transmission can wait (at most)
 603  * @param notify function to call to get the content
 604  * @param notify_cls closure for notify
 605  */
 606 static void
 607 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h,
 608                            size_t size,
 609                            int at_head,
 610                            struct GNUNET_TIME_Relative timeout,
 611                            GNUNET_CONNECTION_TransmitReadyNotify notify,
 612                            void *notify_cls)
 613 {
 614   struct GNUNET_TRANSPORT_TransmitHandle *th;
 615
 616 #if DEBUG_TRANSPORT
 617   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 618               "Control transmit of %u bytes within %llums requested\n",
 619               size, (unsigned long long) timeout.value);
 620 #endif
 621   th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
 622   th->handle = h;
 623   th->notify = notify;
 624   th->notify_cls = notify_cls;
 625   th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
 626   th->notify_size = size;
 627   th->notify_delay_task
 628     = GNUNET_SCHEDULER_add_delayed (h->sched,
 629                                     timeout, &peer_transmit_timeout, th);
 630   if (at_head)
 631     {
 632       th->next = h->connect_ready_head;
 633       h->connect_ready_head = th;
 634       if (th->next != NULL)
 635         th->next->prev = th;
 636     }
 637   else
 638     {
 639       insert_transmit_handle (&h->connect_ready_head, th);
 640     }
 641   if (GNUNET_NO == h->transmission_scheduled)
 642     schedule_transmission (h);
 643 }
 644
 645
 646 /**
 647  * Update the quota values for the given neighbour now.
 648  */
 649 static void
 650 update_quota (struct NeighbourList *n)
 651 {
 652   struct GNUNET_TIME_Relative delta;
 653   uint64_t allowed;
 654   uint64_t remaining;
 655
 656   delta = GNUNET_TIME_absolute_get_duration (n->last_quota_update);
 657   allowed = delta.value * n->quota_out;
 658   if (n->last_sent < allowed)
 659     {
 660       remaining = allowed - n->last_sent;
 661       if (n->quota_out > 0)
 662         remaining /= n->quota_out;
 663       else
 664         remaining = 0;
 665       if (remaining > MAX_BANDWIDTH_CARRY)
 666         remaining = MAX_BANDWIDTH_CARRY;
 667       n->last_sent = 0;
 668       n->last_quota_update = GNUNET_TIME_absolute_get ();
 669       n->last_quota_update.value -= remaining;
 670     }
 671   else
 672     {
 673       n->last_sent -= allowed;
 674       n->last_quota_update = GNUNET_TIME_absolute_get ();
 675     }
 676 }
 677
 678
 679 struct SetQuotaContext
 680 {
 681   struct GNUNET_TRANSPORT_Handle *handle;
 682
 683   struct GNUNET_PeerIdentity target;
 684
 685   GNUNET_SCHEDULER_Task cont;
 686
 687   void *cont_cls;
 688
 689   struct GNUNET_TIME_Absolute timeout;
 690
 691   uint32_t quota_in;
 692 };
 693
 694
 695 static size_t
 696 send_set_quota (void *cls, size_t size, void *buf)
 697 {
 698   struct SetQuotaContext *sqc = cls;
 699   struct QuotaSetMessage *msg;
 700
 701   if (buf == NULL)
 702     {
 703       GNUNET_SCHEDULER_add_continuation (sqc->handle->sched,
 704                                          sqc->cont,
 705                                          sqc->cont_cls,
 706                                          GNUNET_SCHEDULER_REASON_TIMEOUT);
 707       GNUNET_free (sqc);
 708       return 0;
 709     }
 710 #if DEBUG_TRANSPORT
 711   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 712               "Transmitting `%s' request with respect to `%4s'.\n",
 713               "SET_QUOTA", GNUNET_i2s (&sqc->target));
 714 #endif
 715   GNUNET_assert (size >= sizeof (struct QuotaSetMessage));
 716   msg = buf;
 717   msg->header.size = htons (sizeof (struct QuotaSetMessage));
 718   msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA);
 719   msg->quota_in = htonl (sqc->quota_in);
 720   memcpy (&msg->peer, &sqc->target, sizeof (struct GNUNET_PeerIdentity));
 721   if (sqc->cont != NULL)
 722     GNUNET_SCHEDULER_add_continuation (sqc->handle->sched,
 723                                        sqc->cont,
 724                                        sqc->cont_cls,
 725                                        GNUNET_SCHEDULER_REASON_PREREQ_DONE);
 726   GNUNET_free (sqc);
 727   return sizeof (struct QuotaSetMessage);
 728 }
 729
 730
 731 /**
 732  * Set the share of incoming bandwidth for the given
 733  * peer to the specified amount.
 734  *
 735  * @param handle connection to transport service
 736  * @param target who's bandwidth quota is being changed
 737  * @param quota_in incoming bandwidth quota in bytes per ms
 738  * @param quota_out outgoing bandwidth quota in bytes per ms
 739  * @param timeout how long to wait until signaling failure if
 740  *        we can not communicate the quota change
 741  * @param cont continuation to call when done, will be called
 742  *        either with reason "TIMEOUT" or with reason "PREREQ_DONE"
 743  * @param cont_cls closure for continuation
 744  */
 745 void
 746 GNUNET_TRANSPORT_set_quota (struct GNUNET_TRANSPORT_Handle *handle,
 747                             const struct GNUNET_PeerIdentity *target,
 748                             uint32_t quota_in,
 749                             uint32_t quota_out,
 750                             struct GNUNET_TIME_Relative timeout,
 751                             GNUNET_SCHEDULER_Task cont, void *cont_cls)
 752 {
 753   struct NeighbourList *n;
 754   struct SetQuotaContext *sqc;
 755
 756   n = find_neighbour (handle, target);
 757   if (n != NULL)
 758     {
 759       update_quota (n);
 760       if (n->quota_out < quota_out)
 761         n->last_quota_update = GNUNET_TIME_absolute_get ();
 762       n->quota_out = quota_out;
 763     }
 764   sqc = GNUNET_malloc (sizeof (struct SetQuotaContext));
 765   sqc->handle = handle;
 766   sqc->target = *target;
 767   sqc->cont = cont;
 768   sqc->cont_cls = cont_cls;
 769   sqc->timeout = GNUNET_TIME_relative_to_absolute (timeout);
 770   sqc->quota_in = quota_in;
 771   schedule_control_transmit (handle,
 772                              sizeof (struct QuotaSetMessage),
 773                              GNUNET_NO, timeout, &send_set_quota, sqc);
 774 }
 775
 776
 777 /**
 778  * Obtain the HELLO message for this peer.
 779  *
 780  * @param handle connection to transport service
 781  * @param timeout how long to wait for the HELLO
 782  * @param rec function to call with the HELLO, sender will be our peer
 783  *            identity; message and sender will be NULL on timeout
 784  *            (handshake with transport service pending/failed).
 785  *             cost estimate will be 0.
 786  * @param rec_cls closure for rec
 787  */
 788 void
 789 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
 790                             GNUNET_TRANSPORT_HelloUpdateCallback rec,
 791                             void *rec_cls)
 792 {
 793   struct HelloWaitList *hwl;
 794
 795   hwl = GNUNET_malloc (sizeof (struct HelloWaitList));
 796   hwl->next = handle->hwl_head;
 797   handle->hwl_head = hwl;
 798   hwl->handle = handle;
 799   hwl->rec = rec;
 800   hwl->rec_cls = rec_cls;
 801   if (handle->my_hello == NULL)
 802     return;
 803   rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello);
 804 }
 805
 806
 807
 808 /**
 809  * Stop receiving updates about changes to our HELLO message.
 810  *
 811  * @param handle connection to transport service
 812  * @param rec function previously registered to be called with the HELLOs
 813  * @param rec_cls closure for rec
 814  */
 815 void
 816 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_Handle *handle,
 817                                    GNUNET_TRANSPORT_HelloUpdateCallback rec,
 818                                    void *rec_cls)
 819 {
 820   struct HelloWaitList *pos;
 821   struct HelloWaitList *prev;
 822
 823   prev = NULL;
 824   pos = handle->hwl_head;
 825   while (pos != NULL)
 826     {
 827       if ( (pos->rec == rec) &&
 828            (pos->rec_cls == rec_cls) )
 829         break;
 830       prev = pos;
 831       pos = pos->next;
 832     }
 833   GNUNET_break (pos != NULL);
 834   if (pos == NULL)
 835     return;
 836   if (prev == NULL)
 837     handle->hwl_head = pos->next;
 838   else
 839     prev->next = pos->next;
 840   GNUNET_free (pos);
 841 }
 842
 843
 844 static size_t
 845 send_hello (void *cls, size_t size, void *buf)
 846 {
 847   struct GNUNET_MessageHeader *hello = cls;
 848   uint16_t msize;
 849
 850   if (buf == NULL)
 851     {
 852 #if DEBUG_TRANSPORT
 853       GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 854                   "Timeout while trying to transmit `%s' request.\n",
 855                   "HELLO");
 856 #endif
 857       GNUNET_free (hello);
 858       return 0;
 859     }
 860 #if DEBUG_TRANSPORT
 861   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 862               "Transmitting `%s' request.\n", "HELLO");
 863 #endif
 864   msize = ntohs (hello->size);
 865   GNUNET_assert (size >= msize);
 866   memcpy (buf, hello, msize);
 867   GNUNET_free (hello);
 868   return msize;
 869 }
 870
 871
 872 /**
 873  * Offer the transport service the HELLO of another peer.  Note that
 874  * the transport service may just ignore this message if the HELLO is
 875  * malformed or useless due to our local configuration.
 876  *
 877  * @param handle connection to transport service
 878  * @param hello the hello message
 879  */
 880 void
 881 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
 882                               const struct GNUNET_MessageHeader *hello)
 883 {
 884   struct GNUNET_MessageHeader *hc;
 885   uint16_t size;
 886
 887   if (handle->client == NULL)
 888     {
 889 #if DEBUG_TRANSPORT
 890       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 891                   "Not connected to transport service, dropping offered HELLO\n");
 892 #endif
 893       return;
 894     }
 895   GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
 896   size = ntohs (hello->size);
 897   GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
 898   hc = GNUNET_malloc (size);
 899   memcpy (hc, hello, size);
 900   schedule_control_transmit (handle,
 901                              size,
 902                              GNUNET_NO, OFFER_HELLO_TIMEOUT, &send_hello, hc);
 903 }
 904
 905
 906 /**
 907  * Function we use for handling incoming messages.
 908  */
 909 static void demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg);
 910
 911
 912 static size_t
 913 send_start (void *cls, size_t size, void *buf)
 914 {
 915   struct GNUNET_MessageHeader *s = buf;
 916
 917   if (buf == NULL)
 918     {
 919 #if DEBUG_TRANSPORT
 920       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 921                   "Timeout while trying to transmit `%s' request.\n",
 922                   "START");
 923 #endif
 924       return 0;
 925     }
 926 #if DEBUG_TRANSPORT
 927   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 928               "Transmitting `%s' request.\n", "START");
 929 #endif
 930   GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
 931   s->size = htons (sizeof (struct GNUNET_MessageHeader));
 932   s->type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
 933   return sizeof (struct GNUNET_MessageHeader);
 934 }
 935
 936
 937 /**
 938  * We're ready to transmit the request that the transport service
 939  * should connect to a new peer.  In addition to sending the
 940  * request, schedule the next phase for the transmission processing
 941  * that caused the connect request in the first place.
 942  */
 943 static size_t
 944 request_connect (void *cls, size_t size, void *buf)
 945 {
 946   struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
 947   struct TryConnectMessage *tcm;
 948   struct GNUNET_TRANSPORT_Handle *h;
 949
 950   GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK);
 951   h = th->handle;
 952
 953   if (buf == NULL)
 954     {
 955 #if DEBUG_TRANSPORT
 956       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 957                   "Failed to transmit `%s' request for `%4s' to service.\n",
 958                   "TRY_CONNECT", GNUNET_i2s (&th->target));
 959 #endif
 960       if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
 961         {
 962           GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task);
 963           th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
 964         }
 965       if (NULL != th->notify)
 966         GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
 967       GNUNET_free (th);
 968       return 0;
 969     }
 970 #if DEBUG_TRANSPORT
 971   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 972               "Transmitting `%s' message for `%4s' (need connection in %llu ms).\n",
 973               "TRY_CONNECT", GNUNET_i2s (&th->target),
 974               GNUNET_TIME_absolute_get_remaining (th->timeout).value);
 975 #endif
 976   GNUNET_assert (size >= sizeof (struct TryConnectMessage));
 977   tcm = buf;
 978   tcm->header.size = htons (sizeof (struct TryConnectMessage));
 979   tcm->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_TRY_CONNECT);
 980   tcm->reserved = htonl (0);
 981   memcpy (&tcm->peer, &th->target, sizeof (struct GNUNET_PeerIdentity));
 982   th->notify_delay_task
 983     = GNUNET_SCHEDULER_add_delayed (h->sched,
 984                                     GNUNET_TIME_absolute_get_remaining
 985                                     (th->timeout),
 986                                     &peer_transmit_timeout, th);
 987   insert_transmit_handle (&h->connect_wait_head, th);
 988   return sizeof (struct TryConnectMessage);
 989 }
 990
 991
 992 /**
 993  * Schedule a request to connect to the given
 994  * neighbour (and if successful, add the specified
 995  * handle to the wait list).
 996  *
 997  * @param th handle for a request to transmit once we
 998  *        have connected
 999  */
1000 static void
1001 try_connect (struct GNUNET_TRANSPORT_TransmitHandle *th)
1002 {
1003   GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK);
1004   schedule_control_transmit (th->handle,
1005                              sizeof (struct TryConnectMessage),
1006                              GNUNET_NO,
1007                              GNUNET_TIME_absolute_get_remaining (th->timeout),
1008                              &request_connect, th);
1009 }
1010
1011
1012 /**
1013  * Task for delayed attempts to reconnect to a peer.
1014  *
1015  * @param cls must be a transmit handle that determines the peer
1016  *        to which we will try to connect
1017  * @param tc scheduler information about why we were triggered (not used)
1018  */
1019 static void
1020 try_connect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1021 {
1022   struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
1023
1024   th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1025   try_connect (th);
1026 }
1027
1028
1029 /**
1030  * Remove neighbour from our list.  Will automatically
1031  * trigger a re-connect attempt if we have messages pending
1032  * for this peer.
1033  *
1034  * @param h our state
1035  * @param peer the peer to remove
1036  */
1037 static void
1038 remove_neighbour (struct GNUNET_TRANSPORT_Handle *h,
1039                   const struct GNUNET_PeerIdentity *peer)
1040 {
1041   struct NeighbourList *prev;
1042   struct NeighbourList *pos;
1043   struct GNUNET_TRANSPORT_TransmitHandle *th;
1044
1045 #if DEBUG_TRANSPORT
1046   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1047               "Removing neighbour `%s' from list of connected peers.\n",
1048               GNUNET_i2s (peer));
1049 #endif
1050   prev = NULL;
1051   pos = h->neighbours;
1052   while ((pos != NULL) &&
1053          (0 != memcmp (peer, &pos->id, sizeof (struct GNUNET_PeerIdentity))))
1054     {
1055       prev = pos;
1056       pos = pos->next;
1057     }
1058   if (pos == NULL)
1059     {
1060       GNUNET_break (0);
1061       return;
1062     }
1063   if (prev == NULL)
1064     h->neighbours = pos->next;
1065   else
1066     prev->next = pos->next;
1067   if (NULL != (th = pos->transmit_handle))
1068     {
1069       pos->transmit_handle = NULL;
1070       th->neighbour = NULL;
1071       remove_from_any_list (th);
1072       if (GNUNET_TIME_absolute_get_remaining (th->timeout).value <=
1073           CONNECT_RETRY_TIMEOUT.value)
1074         {
1075           /* signal error */
1076           GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1077                       _
1078                       ("Connection with `%4s' failed and timeout was in the past, giving up on message delivery.\n"),
1079                       GNUNET_i2s (peer));
1080           GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == th->notify_delay_task);
1081           peer_transmit_timeout (th, NULL);
1082         }
1083       else
1084         {
1085           GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1086                       _
1087                       ("Connection with `%4s' failed, will keep trying for %llu ms to deliver message\n"),
1088                       GNUNET_i2s (peer),
1089                       GNUNET_TIME_absolute_get_remaining (th->timeout).value);
1090           /* try again in a bit */
1091           GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == th->notify_delay_task);
1092           th->notify_delay_task
1093             = GNUNET_SCHEDULER_add_delayed (h->sched,
1094                                             CONNECT_RETRY_TIMEOUT,
1095                                             &try_connect_task, th);
1096         }
1097     }
1098   if (h->nc_cb != NULL)
1099     h->nd_cb (h->cls, peer);
1100   GNUNET_free (pos);
1101 }
1102
1103
1104 /**
1105  * Try again to connect to transport service.
1106  */
1107 static void
1108 reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1109 {
1110   struct GNUNET_TRANSPORT_Handle *h = cls;
1111   struct GNUNET_TRANSPORT_TransmitHandle *pos;
1112   struct NeighbourList *n;
1113
1114   /* Forget about all neighbours that we used to be connected
1115      to */
1116   while (NULL != (n = h->neighbours))
1117     remove_neighbour (h, &n->id);
1118 #if DEBUG_TRANSPORT
1119   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n");
1120 #endif
1121   GNUNET_assert (h->client == NULL);
1122   h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1123   h->client = GNUNET_CLIENT_connect (h->sched, "transport", h->cfg);
1124   GNUNET_assert (h->client != NULL);
1125   /* make sure we don't send "START" twice,
1126      remove existing entry from queue (if present) */
1127   pos = h->connect_ready_head;
1128   while (pos != NULL)
1129     {
1130       if (pos->notify == &send_start)
1131         {
1132           if (pos->prev == NULL)
1133             h->connect_ready_head = pos->next;
1134           else
1135             pos->prev->next = pos->next;
1136           if (pos->next != NULL)
1137             pos->next->prev = pos->prev;
1138           GNUNET_assert (pos->neighbour == NULL);
1139           if (GNUNET_SCHEDULER_NO_TASK != pos->notify_delay_task)
1140             {
1141               GNUNET_SCHEDULER_cancel (h->sched, pos->notify_delay_task);
1142               pos->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1143             }
1144           GNUNET_free (pos);
1145           break;
1146         }
1147       pos = pos->next;
1148     }
1149   schedule_control_transmit (h,
1150                              sizeof (struct GNUNET_MessageHeader),
1151                              GNUNET_YES,
1152                              GNUNET_TIME_UNIT_FOREVER_REL, &send_start, NULL);
1153   GNUNET_CLIENT_receive (h->client,
1154                          &demultiplexer, h, GNUNET_TIME_UNIT_FOREVER_REL);
1155 }
1156
1157
1158 /**
1159  * Function that will schedule the job that will try
1160  * to connect us again to the client.
1161  */
1162 static void
1163 schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
1164 {
1165 #if DEBUG_TRANSPORT
1166   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1167               "Scheduling task to reconnect to transport service in %llu ms.\n",
1168               h->reconnect_delay.value);
1169 #endif
1170   GNUNET_assert (h->client == NULL);
1171   GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
1172   h->reconnect_task
1173     = GNUNET_SCHEDULER_add_delayed (h->sched,
1174                                     h->reconnect_delay, &reconnect, h);
1175   h->reconnect_delay = GNUNET_TIME_UNIT_SECONDS;
1176 }
1177
1178
1179 /**
1180  * We are connected to the respective peer, check the
1181  * bandwidth limits and schedule the transmission.
1182  */
1183 static void schedule_request (struct GNUNET_TRANSPORT_TransmitHandle *th);
1184
1185
1186 /**
1187  * Function called by the scheduler when the timeout
1188  * for bandwidth availablility for the target
1189  * neighbour is reached.
1190  */
1191 static void
1192 transmit_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1193 {
1194   struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
1195
1196   th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1197   schedule_request (th);
1198 }
1199
1200
1201 /**
1202  * Remove the given transmit handle from the wait list.  Does NOT free
1203  * it.
1204  */
1205 static void
1206 remove_from_wait_list (struct GNUNET_TRANSPORT_TransmitHandle *th)
1207 {
1208   if (th->prev == NULL)
1209     th->handle->connect_wait_head = th->next;
1210   else
1211     th->prev->next = th->next;
1212   if (th->next != NULL)
1213     th->next->prev = th->prev;
1214 }
1215
1216
1217 /**
1218  * We are connected to the respective peer, check the
1219  * bandwidth limits and schedule the transmission.
1220  */
1221 static void
1222 schedule_request (struct GNUNET_TRANSPORT_TransmitHandle *th)
1223 {
1224   struct GNUNET_TRANSPORT_Handle *h;
1225   struct GNUNET_TIME_Relative duration;
1226   struct NeighbourList *n;
1227   uint64_t available;
1228
1229   h = th->handle;
1230   n = th->neighbour;
1231   if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
1232     {
1233       GNUNET_SCHEDULER_cancel (h->sched, th->notify_delay_task);
1234       th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1235     }
1236   /* check outgoing quota */
1237   duration = GNUNET_TIME_absolute_get_duration (n->last_quota_update);
1238   if (duration.value > MIN_QUOTA_REFRESH_TIME)
1239     {
1240       update_quota (n);
1241       duration = GNUNET_TIME_absolute_get_duration (n->last_quota_update);
1242     }
1243   available = duration.value * n->quota_out;
1244   if (available < n->last_sent + th->notify_size)
1245     {
1246       /* calculate how much bandwidth we'd still need to
1247          accumulate and based on that how long we'll have
1248          to wait... */
1249       available = n->last_sent + th->notify_size - available;
1250       duration = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS,
1251                                                 available / n->quota_out);
1252       if (th->timeout.value <
1253           GNUNET_TIME_relative_to_absolute (duration).value)
1254         {
1255           /* signal timeout! */
1256 #if DEBUG_TRANSPORT
1257           GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1258                       "Would need %llu ms before bandwidth is available for delivery to `%4s', that is too long.  Signaling timeout.\n",
1259                       duration.value, GNUNET_i2s (&th->target));
1260 #endif
1261           remove_from_wait_list (th);
1262           if (NULL != th->notify)
1263             GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
1264           GNUNET_free (th);
1265           return;
1266         }
1267 #if DEBUG_TRANSPORT
1268       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1269                   "Need more bandwidth, delaying delivery to `%4s' by %llu ms\n",
1270                   GNUNET_i2s (&th->target), duration.value);
1271 #endif
1272       th->notify_delay_task
1273         = GNUNET_SCHEDULER_add_delayed (h->sched,
1274                                         duration, &transmit_ready, th);
1275       return;
1276     }
1277 #if DEBUG_TRANSPORT
1278   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1279               "Bandwidth available for transmission to `%4s'\n",
1280               GNUNET_i2s (&n->id));
1281 #endif
1282   if (GNUNET_NO == n->transmit_ok)
1283     {
1284       /* we may be ready, but transport service is not;
1285          wait for SendOkMessage or timeout */
1286 #if DEBUG_TRANSPORT
1287       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1288                   "Need to wait for transport service `%s' message\n",
1289                   "SEND_OK");
1290 #endif
1291       th->notify_delay_task
1292         = GNUNET_SCHEDULER_add_delayed (h->sched,
1293                                         GNUNET_TIME_absolute_get_remaining
1294                                         (th->timeout), &peer_transmit_timeout,
1295                                         th);
1296       return;
1297     }
1298   n->transmit_ok = GNUNET_NO;
1299   remove_from_wait_list (th);
1300 #if DEBUG_TRANSPORT
1301   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1302               "Moving message for `%4s' to ready list\n",
1303               GNUNET_i2s (&n->id));
1304 #endif
1305   insert_transmit_handle (&h->connect_ready_head, th);
1306   if (GNUNET_NO == h->transmission_scheduled)
1307     schedule_transmission (h);
1308 }
1309
1310
1311 /**
1312  * Add neighbour to our list
1313  */
1314 static void
1315 add_neighbour (struct GNUNET_TRANSPORT_Handle *h,
1316                uint32_t quota_out,
1317                struct GNUNET_TIME_Relative latency,
1318                uint16_t distance,
1319                const struct GNUNET_PeerIdentity *pid)
1320 {
1321   struct NeighbourList *n;
1322   struct GNUNET_TRANSPORT_TransmitHandle *prev;
1323   struct GNUNET_TRANSPORT_TransmitHandle *pos;
1324   struct GNUNET_TRANSPORT_TransmitHandle *next;
1325
1326   /* check for duplicates */
1327   if (NULL != find_neighbour (h, pid))
1328     {
1329       GNUNET_break (0);
1330       return;
1331     }
1332 #if DEBUG_TRANSPORT
1333   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1334               "Creating entry for new neighbour `%4s'.\n", GNUNET_i2s (pid));
1335 #endif
1336   n = GNUNET_malloc (sizeof (struct NeighbourList));
1337   n->id = *pid;
1338   n->last_quota_update = GNUNET_TIME_absolute_get ();
1339   n->quota_out = quota_out;
1340   n->next = h->neighbours;
1341   n->transmit_ok = GNUNET_YES;
1342   h->neighbours = n;
1343   if (h->nc_cb != NULL)
1344     h->nc_cb (h->cls, &n->id, latency, distance);
1345   prev = NULL;
1346   pos = h->connect_wait_head;
1347   while (pos != NULL)
1348     {
1349       next = pos->next;
1350       if (0 == memcmp (pid,
1351                        &pos->target, sizeof (struct GNUNET_PeerIdentity)))
1352         {
1353           pos->neighbour = n;
1354           GNUNET_assert (NULL == n->transmit_handle);
1355           n->transmit_handle = pos;
1356           if (prev == NULL)
1357             h->connect_wait_head = next;
1358           else
1359             prev->next = next;
1360 #if ACK
1361           if (GNUNET_YES == n->received_ack)
1362             {
1363 #endif
1364 #if DEBUG_TRANSPORT
1365               GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1366                           "Found pending request for `%4s' will trigger it now.\n",
1367                           GNUNET_i2s (&pos->target));
1368 #endif
1369               if (pos->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
1370                 {
1371                   GNUNET_SCHEDULER_cancel (h->sched, pos->notify_delay_task);
1372                   pos->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1373                 }
1374               schedule_request (pos);
1375 #if ACK
1376             }
1377 #endif
1378
1379           break;
1380         }
1381       prev = pos;
1382       pos = next;
1383     }
1384 }
1385
1386
1387 /**
1388  * Connect to the transport service.  Note that the connection may
1389  * complete (or fail) asynchronously.
1390  *
1391
1392  * @param sched scheduler to use
1393  * @param cfg configuration to use
1394  * @param cls closure for the callbacks
1395  * @param rec receive function to call
1396  * @param nc function to call on connect events
1397  * @param nd function to call on disconnect events
1398  */
1399 struct GNUNET_TRANSPORT_Handle *
1400 GNUNET_TRANSPORT_connect (struct GNUNET_SCHEDULER_Handle *sched,
1401                           const struct GNUNET_CONFIGURATION_Handle *cfg,
1402                           void *cls,
1403                           GNUNET_TRANSPORT_ReceiveCallback rec,
1404                           GNUNET_TRANSPORT_NotifyConnect nc,
1405                           GNUNET_TRANSPORT_NotifyDisconnect nd)
1406 {
1407   struct GNUNET_TRANSPORT_Handle *ret;
1408
1409   GNUNET_ARM_start_services (cfg, sched, "peerinfo", "transport", NULL);
1410   ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle));
1411   ret->sched = sched;
1412   ret->cfg = cfg;
1413   ret->cls = cls;
1414   ret->rec = rec;
1415   ret->nc_cb = nc;
1416   ret->nd_cb = nd;
1417   ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1418   schedule_reconnect (ret);
1419   return ret;
1420 }
1421
1422
1423 /**
1424  * Disconnect from the transport service.
1425  */
1426 void
1427 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1428 {
1429   struct GNUNET_TRANSPORT_TransmitHandle *th;
1430   struct NeighbourList *n;
1431   struct HelloWaitList *hwl;
1432   struct GNUNET_CLIENT_Connection *client;
1433
1434 #if DEBUG_TRANSPORT
1435   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n");
1436 #endif
1437   while (NULL != (th = handle->connect_ready_head))
1438     {
1439       handle->connect_ready_head = th->next;
1440       if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
1441         {
1442           GNUNET_SCHEDULER_cancel (handle->sched, th->notify_delay_task);
1443           th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1444         }
1445       if (NULL != th->notify)
1446         GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
1447       GNUNET_free (th);
1448     }
1449   while (NULL != (th = handle->connect_wait_head))
1450     {
1451       handle->connect_wait_head = th->next;
1452       if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
1453         {
1454           GNUNET_SCHEDULER_cancel (handle->sched, th->notify_delay_task);
1455           th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1456         }
1457       if (NULL != th->notify)
1458         GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
1459       GNUNET_free (th);
1460     }
1461   while (NULL != (n = handle->neighbours))
1462     {
1463       handle->neighbours = n->next;
1464       if (NULL != (th = n->transmit_handle))
1465         {
1466           if (th->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
1467             {
1468               GNUNET_SCHEDULER_cancel (handle->sched, th->notify_delay_task);
1469               th->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1470             }
1471           if (NULL != th->notify)
1472             GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
1473           GNUNET_free (th);
1474         }
1475       GNUNET_free (n);
1476     }
1477   while (NULL != (hwl = handle->hwl_head))
1478     {
1479       handle->hwl_head = hwl->next;
1480       GNUNET_SCHEDULER_cancel (handle->sched, hwl->task);
1481       GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1482                   _
1483                   ("Disconnect while notification for `%s' still registered.\n"),
1484                   "HELLO");
1485       if (hwl->rec != NULL)
1486         hwl->rec (hwl->rec_cls, NULL);
1487       GNUNET_free (hwl);
1488     }
1489   if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1490     {
1491       GNUNET_SCHEDULER_cancel (handle->sched, handle->reconnect_task);
1492       handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1493     }
1494   GNUNET_free_non_null (handle->my_hello);
1495   handle->my_hello = NULL;
1496   GNUNET_ARM_stop_services (handle->cfg, handle->sched, "transport",
1497                             "peerinfo", NULL);
1498   if (NULL != handle->network_handle)
1499     {
1500       GNUNET_CLIENT_notify_transmit_ready_cancel (handle->network_handle);
1501       handle->network_handle = NULL;
1502     }
1503   if (NULL != (client = handle->client))
1504     {
1505 #if DEBUG_TRANSPORT
1506       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1507                   "Disconnecting from transport service for good.\n");
1508 #endif
1509       handle->client = NULL;
1510       GNUNET_CLIENT_disconnect (client);
1511     }
1512   GNUNET_free (handle);
1513 }
1514
1515
1516 /**
1517  * Type of a function to call when we receive a message
1518  * from the service.
1519  *
1520  * @param cls closure
1521  * @param msg message received, NULL on timeout or fatal error
1522  */
1523 static void
1524 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
1525 {
1526   struct GNUNET_TRANSPORT_Handle *h = cls;
1527   const struct DisconnectInfoMessage *dim;
1528   const struct ConnectInfoMessage *cim;
1529   const struct InboundMessage *im;
1530   const struct GNUNET_MessageHeader *imm;
1531   const struct SendOkMessage *okm;
1532   struct HelloWaitList *hwl;
1533   struct HelloWaitList *next_hwl;
1534   struct NeighbourList *n;
1535   struct GNUNET_PeerIdentity me;
1536   struct GNUNET_TRANSPORT_TransmitHandle *th;
1537
1538   struct GNUNET_TRANSPORT_TransmitHandle *prev;
1539   struct GNUNET_TRANSPORT_TransmitHandle *pos;
1540   struct GNUNET_TRANSPORT_TransmitHandle *next;
1541   uint16_t size;
1542
1543   if ((msg == NULL) || (h->client == NULL))
1544     {
1545       if (h->client != NULL)
1546         {
1547 #if DEBUG_TRANSPORT
1548           GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1549                       "Error receiving from transport service, disconnecting temporarily.\n");
1550 #endif
1551           if (h->network_handle != NULL)
1552             {
1553               GNUNET_CLIENT_notify_transmit_ready_cancel (h->network_handle);
1554               h->network_handle = NULL;
1555               h->transmission_scheduled = GNUNET_NO;
1556               th = h->connect_ready_head;
1557               /* add timeout again, we cancelled the transmit_ready task! */
1558               GNUNET_assert (th->notify_delay_task ==
1559                              GNUNET_SCHEDULER_NO_TASK);
1560               th->notify_delay_task =
1561                 GNUNET_SCHEDULER_add_delayed (h->sched,
1562                                               GNUNET_TIME_absolute_get_remaining
1563                                               (th->timeout),
1564                                               &peer_transmit_timeout, th);
1565             }
1566           GNUNET_CLIENT_disconnect (h->client);
1567           h->client = NULL;
1568           schedule_reconnect (h);
1569         }
1570       else
1571         {
1572           /* shutdown initiated from 'GNUNET_TRANSPORT_disconnect',
1573              finish clean up work! */
1574           GNUNET_free (h);
1575         }
1576       return;
1577     }
1578   GNUNET_CLIENT_receive (h->client,
1579                          &demultiplexer, h, GNUNET_TIME_UNIT_FOREVER_REL);
1580   size = ntohs (msg->size);
1581   switch (ntohs (msg->type))
1582     {
1583     case GNUNET_MESSAGE_TYPE_HELLO:
1584       if (GNUNET_OK !=
1585           GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg,
1586                                &me))
1587         {
1588           GNUNET_break (0);
1589           break;
1590         }
1591 #if DEBUG_TRANSPORT
1592       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1593                   "Receiving (my own) `%s' message, I am `%4s'.\n",
1594                   "HELLO", GNUNET_i2s (&me));
1595 #endif
1596       GNUNET_free_non_null (h->my_hello);
1597       h->my_hello = NULL;
1598       if (size < sizeof (struct GNUNET_MessageHeader))
1599         {
1600           GNUNET_break (0);
1601           break;
1602         }
1603       h->my_hello = GNUNET_malloc (size);
1604       memcpy (h->my_hello, msg, size);
1605       hwl = h->hwl_head;
1606       while (NULL != hwl)
1607         {
1608           next_hwl = hwl->next;
1609           hwl->rec (hwl->rec_cls,
1610                     (const struct GNUNET_MessageHeader *) h->my_hello);
1611           hwl = next_hwl;
1612         }
1613       break;
1614     case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
1615       if (size != sizeof (struct ConnectInfoMessage))
1616         {
1617           GNUNET_break (0);
1618           break;
1619         }
1620       cim = (const struct ConnectInfoMessage *) msg;
1621 #if DEBUG_TRANSPORT
1622       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1623                   "Receiving `%s' message for `%4s'.\n",
1624                   "CONNECT", GNUNET_i2s (&cim->id));
1625 #endif
1626       if (find_neighbour(h, &cim->id) == NULL)
1627         {
1628 #if DEBUG_TRANSPORT
1629               GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1630                           "Don't know neighbor, adding!\n");
1631 #endif
1632           add_neighbour (h,
1633                          ntohl (cim->quota_out),
1634                          GNUNET_TIME_relative_ntoh (cim->latency), ntohs(cim->distance), &cim->id);
1635         }
1636       else
1637         {
1638 #if DEBUG_TRANSPORT
1639               GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1640                           "Do know neighbor, scheduling transmission!\n");
1641 #endif
1642           n = find_neighbour(h, &cim->id);
1643           n->received_ack = GNUNET_YES;
1644           if (NULL != n->transmit_handle)
1645             {
1646 #if DEBUG_TRANSPORT
1647               GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1648                           "Peer connected, scheduling delayed message for delivery now.\n");
1649 #endif
1650               schedule_request (n->transmit_handle);
1651             }
1652           else
1653             {
1654 #if DEBUG_TRANSPORT
1655               GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1656                           "Transmit handle is null... Checking for pending stuff(?)\n");
1657 #endif
1658               prev = NULL;
1659               pos = h->connect_wait_head;
1660               while (pos != NULL)
1661                 {
1662                   next = pos->next;
1663                   if (0 == memcmp (&cim->id,
1664                                    &pos->target, sizeof (struct GNUNET_PeerIdentity)))
1665                     {
1666                       pos->neighbour = n;
1667                       GNUNET_assert (NULL == n->transmit_handle);
1668                       n->transmit_handle = pos;
1669                       if (prev == NULL)
1670                         h->connect_wait_head = next;
1671                       else
1672                         prev->next = next;
1673 #if ACK
1674                         if (GNUNET_YES == n->received_ack)
1675                           {
1676 #endif
1677   #if DEBUG_TRANSPORT
1678                           GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1679                                       "Found pending request for `%4s' will trigger it now.\n",
1680                                       GNUNET_i2s (&pos->target));
1681   #endif
1682                           if (pos->notify_delay_task != GNUNET_SCHEDULER_NO_TASK)
1683                             {
1684                               GNUNET_SCHEDULER_cancel (h->sched, pos->notify_delay_task);
1685                               pos->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1686                             }
1687                           schedule_request (pos);
1688 #if ACK
1689                           }
1690 #endif
1691
1692                       break;
1693                     }
1694                   prev = pos;
1695                   pos = next;
1696                 }
1697           }
1698         }
1699
1700       break;
1701     case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
1702       if (size != sizeof (struct DisconnectInfoMessage))
1703         {
1704           GNUNET_break (0);
1705           break;
1706         }
1707       dim = (const struct DisconnectInfoMessage *) msg;
1708 #if DEBUG_TRANSPORT
1709       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1710                   "Receiving `%s' message for `%4s'.\n",
1711                   "DISCONNECT", GNUNET_i2s (&dim->peer));
1712 #endif
1713       remove_neighbour (h, &dim->peer);
1714       break;
1715     case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
1716       if (size != sizeof (struct SendOkMessage))
1717         {
1718           GNUNET_break (0);
1719           break;
1720         }
1721       okm = (const struct SendOkMessage *) msg;
1722 #if DEBUG_TRANSPORT
1723       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1724                   "Receiving `%s' message, transmission %s.\n", "SEND_OK",
1725                   ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
1726 #endif
1727       n = find_neighbour (h, &okm->peer);
1728       GNUNET_assert (n != NULL);
1729       n->transmit_ok = GNUNET_YES;
1730       if (n->transmit_handle != NULL)
1731         {
1732 #if DEBUG_TRANSPORT
1733           GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1734                       "Processing pending message for `%4s'\n",
1735                       GNUNET_i2s (&n->id));
1736 #endif
1737           GNUNET_SCHEDULER_cancel (h->sched,
1738                                    n->transmit_handle->notify_delay_task);
1739           n->transmit_handle->notify_delay_task = GNUNET_SCHEDULER_NO_TASK;
1740           GNUNET_assert (GNUNET_YES == n->received_ack);
1741           schedule_request (n->transmit_handle);
1742         }
1743       break;
1744     case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
1745 #if DEBUG_TRANSPORT
1746       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1747                   "Receiving `%s' message.\n", "RECV");
1748 #endif
1749       if (size <
1750           sizeof (struct InboundMessage) +
1751           sizeof (struct GNUNET_MessageHeader))
1752         {
1753           GNUNET_break (0);
1754           break;
1755         }
1756       im = (const struct InboundMessage *) msg;
1757       imm = (const struct GNUNET_MessageHeader *) &im[1];
1758       if (ntohs (imm->size) + sizeof (struct InboundMessage) != size)
1759         {
1760           GNUNET_break (0);
1761           break;
1762         }
1763       switch (ntohs (imm->type))
1764         {
1765         case GNUNET_MESSAGE_TYPE_TRANSPORT_ACK:
1766 #if DEBUG_TRANSPORT
1767           GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1768                       "Receiving `%s' message from `%4s'.\n",
1769                       "ACK", GNUNET_i2s (&im->peer));
1770 #endif
1771           n = find_neighbour (h, &im->peer);
1772           if (n == NULL)
1773             {
1774               GNUNET_break (0);
1775               break;
1776             }
1777           if (n->received_ack == GNUNET_NO)
1778             {
1779               n->received_ack = GNUNET_YES;
1780               if (NULL != n->transmit_handle)
1781                 {
1782 #if DEBUG_TRANSPORT
1783                   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1784                               "Peer connected, scheduling delayed message for delivery now.\n");
1785 #endif
1786                   schedule_request (n->transmit_handle);
1787                 }
1788             }
1789           break;
1790         default:
1791 #if DEBUG_TRANSPORT
1792           GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1793                       "Received message of type %u from `%4s'.\n",
1794                       ntohs (imm->type), GNUNET_i2s (&im->peer));
1795 #endif
1796           if (h->rec != NULL)
1797             h->rec (h->cls, &im->peer, imm,
1798                     GNUNET_TIME_relative_ntoh (im->latency), ntohs(im->distance));
1799           break;
1800         }
1801       break;
1802     default:
1803       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1804                   _
1805                   ("Received unexpected message of type %u in %s:%u\n"),
1806                   ntohs (msg->type), __FILE__, __LINE__);
1807       GNUNET_break (0);
1808       break;
1809     }
1810 }
1811
1812
1813 struct ClientTransmitWrapper
1814 {
1815   GNUNET_CONNECTION_TransmitReadyNotify notify;
1816   void *notify_cls;
1817   struct GNUNET_TRANSPORT_TransmitHandle *th;
1818 };
1819
1820
1821 /**
1822  * Transmit message of a client destined for another
1823  * peer to the service.
1824  */
1825 static size_t
1826 client_notify_wrapper (void *cls, size_t size, void *buf)
1827 {
1828   struct ClientTransmitWrapper *ctw = cls;
1829   struct OutboundMessage *obm;
1830   struct GNUNET_MessageHeader *hdr;
1831   size_t ret;
1832
1833   if (size == 0)
1834     {
1835 #if DEBUG_TRANSPORT
1836       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1837                   "Transmission request could not be satisfied.\n");
1838 #endif
1839       if (NULL != ctw->notify)
1840         GNUNET_assert (0 == ctw->notify (ctw->notify_cls, 0, NULL));
1841       GNUNET_free (ctw);
1842       return 0;
1843     }
1844   GNUNET_assert (size >= sizeof (struct OutboundMessage));
1845   obm = buf;
1846   if (ctw->notify != NULL)
1847     ret = ctw->notify (ctw->notify_cls,
1848                        size - sizeof (struct OutboundMessage),
1849                        (void *) &obm[1]);
1850   else
1851     ret = 0;
1852   if (ret == 0)
1853     {
1854       /* Need to reset flag, no SEND means no SEND_OK! */
1855       ctw->th->neighbour->transmit_ok = GNUNET_YES;
1856       GNUNET_free (ctw);
1857       return 0;
1858     }
1859   GNUNET_assert (ret >= sizeof (struct GNUNET_MessageHeader));
1860   hdr = (struct GNUNET_MessageHeader *) &obm[1];
1861   GNUNET_assert (ntohs (hdr->size) == ret);
1862   GNUNET_assert (ret + sizeof (struct OutboundMessage) <
1863                  GNUNET_SERVER_MAX_MESSAGE_SIZE);
1864 #if DEBUG_TRANSPORT
1865   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1866               "Transmitting `%s' message with data for `%4s'\n",
1867               "SEND", GNUNET_i2s (&ctw->th->target));
1868 #endif
1869   ret += sizeof (struct OutboundMessage);
1870   obm->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
1871   obm->header.size = htons (ret);
1872   obm->priority = htonl (ctw->th->priority);
1873   obm->peer = ctw->th->target;
1874   GNUNET_free (ctw);
1875   return ret;
1876 }
1877
1878
1879
1880 /**
1881  * Check if we could queue a message of the given size for
1882  * transmission.  The transport service will take both its
1883  * internal buffers and bandwidth limits imposed by the
1884  * other peer into consideration when answering this query.
1885  *
1886  * @param handle connection to transport service
1887  * @param target who should receive the message
1888  * @param size how big is the message we want to transmit?
1889  * @param priority how important is the message?
1890  * @param timeout after how long should we give up (and call
1891  *        notify with buf NULL and size 0)?
1892  * @param notify function to call when we are ready to
1893  *        send such a message
1894  * @param notify_cls closure for notify
1895  * @return NULL if someone else is already waiting to be notified
1896  *         non-NULL if the notify callback was queued (can be used to cancel
1897  *         using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1898  */
1899 struct GNUNET_TRANSPORT_TransmitHandle *
1900 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle
1901                                         *handle,
1902                                         const struct GNUNET_PeerIdentity
1903                                         *target, size_t size,
1904                                         unsigned int priority,
1905                                         struct GNUNET_TIME_Relative timeout,
1906                                         GNUNET_CONNECTION_TransmitReadyNotify
1907                                         notify, void *notify_cls)
1908 {
1909   struct GNUNET_TRANSPORT_TransmitHandle *pos;
1910   struct GNUNET_TRANSPORT_TransmitHandle *th;
1911   struct NeighbourList *n;
1912   struct ClientTransmitWrapper *ctw;
1913
1914   if (size + sizeof (struct OutboundMessage) >=
1915       GNUNET_SERVER_MAX_MESSAGE_SIZE)
1916     {
1917       GNUNET_break (0);
1918       return NULL;
1919     }
1920 #if DEBUG_TRANSPORT
1921   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1922               "Asking transport service for transmission of %u bytes to peer `%4s'.\n",
1923               size, GNUNET_i2s (target));
1924 #endif
1925   n = find_neighbour (handle, target);
1926   if ((n != NULL) && (n->transmit_handle != NULL))
1927     return NULL;                /* already have a request pending for this peer! */
1928   ctw = GNUNET_malloc (sizeof (struct ClientTransmitWrapper));
1929   th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
1930   ctw->notify = notify;
1931   ctw->notify_cls = notify_cls;
1932   ctw->th = th;
1933   th->handle = handle;
1934   th->neighbour = n;
1935   th->target = *target;
1936   th->notify = &client_notify_wrapper;
1937   th->notify_cls = ctw;
1938   th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1939   th->notify_size = size + sizeof (struct OutboundMessage);
1940   th->priority = priority;
1941   if (NULL == n)
1942     {
1943       pos = handle->connect_wait_head;
1944       while (pos != NULL)
1945         {
1946           GNUNET_assert (0 != memcmp (target,
1947                                       &pos->target,
1948                                       sizeof (struct GNUNET_PeerIdentity)));
1949           pos = pos->next;
1950         }
1951 #if DEBUG_TRANSPORT
1952       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1953                   "Will now try to connect to `%4s'.\n", GNUNET_i2s (target));
1954 #endif
1955       try_connect (th);
1956       return th;
1957     }
1958
1959 #if DEBUG_TRANSPORT
1960   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1961               "Transmission request queued for transmission to transport service.\n");
1962 #endif
1963   GNUNET_assert (NULL == n->transmit_handle);
1964   n->transmit_handle = th;
1965   if (GNUNET_YES != n->transmit_ok)
1966     {
1967 #if DEBUG_TRANSPORT
1968       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1969                   "Connection to `%4s' is not yet confirmed connected, scheduling timeout (%llu ms) only.\n",
1970                   GNUNET_i2s (target), timeout.value);
1971 #endif
1972       th->notify_delay_task
1973         = GNUNET_SCHEDULER_add_delayed (handle->sched,
1974                                         timeout, &peer_transmit_timeout, th);
1975       return th;
1976     }
1977
1978 #if DEBUG_TRANSPORT
1979   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1980               "Peer `%4s' is ready to receive, scheduling message for delivery now.\n",
1981               GNUNET_i2s (target));
1982 #endif
1983   th->notify_delay_task
1984     = GNUNET_SCHEDULER_add_now (handle->sched, &transmit_ready, th);
1985   return th;
1986 }
1987
1988
1989 /**
1990  * Cancel the specified transmission-ready notification.
1991  */
1992 void
1993 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
1994                                                GNUNET_TRANSPORT_TransmitHandle
1995                                                *th)
1996 {
1997   struct GNUNET_TRANSPORT_Handle *h;
1998
1999 #if DEBUG_TRANSPORT
2000   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2001               "Transmission request of %u bytes to `%4s' was cancelled.\n",
2002               th->notify_size - sizeof (struct OutboundMessage),
2003               GNUNET_i2s (&th->target));
2004 #endif
2005   GNUNET_assert (th->notify == &client_notify_wrapper);
2006   remove_from_any_list (th);
2007   h = th->handle;
2008   if ((h->connect_ready_head == NULL) && (h->network_handle != NULL))
2009     {
2010       GNUNET_CLIENT_notify_transmit_ready_cancel (h->network_handle);
2011       h->network_handle = NULL;
2012       h->transmission_scheduled = GNUNET_NO;
2013     }
2014   GNUNET_free (th->notify_cls);
2015   GNUNET_assert (th->notify_delay_task == GNUNET_SCHEDULER_NO_TASK);
2016   GNUNET_free (th);
2017 }
2018
2019
2020 /* end of transport_api.c */