src/mesh/mesh_api_new.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2011 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 3, 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 mesh/mesh_api_new.c
  23  * @brief mesh api: client implementation of mesh service
  24  * @author Bartlomiej Polot
  25  *
  26  * STRUCTURE:
  27  * - CONSTANTS
  28  * - DATA STRUCTURES
  29  * - SEND CALLBACKS
  30  * - RECEIVE HANDLERS
  31  * - API CALL DEFINITIONS
  32  */
  33
  34 #ifdef __cplusplus
  35
  36 extern "C"
  37 {
  38 #if 0                           /* keep Emacsens' auto-indent happy */
  39 }
  40 #endif
  41 #endif
  42
  43
  44 #include "platform.h"
  45 #include "gnunet_common.h"
  46 #include "gnunet_client_lib.h"
  47 #include "gnunet_util_lib.h"
  48 #include "gnunet_peer_lib.h"
  49 #include "gnunet_mesh_service_new.h"
  50 #include "mesh.h"
  51
  52 /******************************************************************************/
  53 /**************************       CONSTANTS      ******************************/
  54 /******************************************************************************/
  55
  56 #define GNUNET_MESH_LOCAL_TUNNEL_ID_MARK 0x80000000
  57
  58 /******************************************************************************/
  59 /************************      DATA STRUCTURES     ****************************/
  60 /******************************************************************************/
  61
  62 /**
  63  * Opaque handle to the service.
  64  */
  65 struct GNUNET_MESH_Handle {
  66     /**
  67      * Handle to the server connection, to send messages later
  68      */
  69     struct GNUNET_CLIENT_Connection             *client;
  70
  71     /**
  72      * Set of handlers used for processing incoming messages in the tunnels
  73      */
  74     const struct GNUNET_MESH_MessageHandler     *message_handlers;
  75     int                                         n_handlers;
  76
  77     /**
  78      * Set of applications that should be claimed to be offered at this node.
  79      * Note that this is just informative, the appropiate handlers must be
  80      * registered independently and the mapping is up to the developer of the
  81      * client application.
  82      */
  83     const GNUNET_MESH_ApplicationType           *applications;
  84     int                                         n_applications;
  85
  86     /**
  87      * Double linked list of the tunnels this client is connected to.
  88      */
  89     struct GNUNET_MESH_Tunnel                   *tunnels_head;
  90     struct GNUNET_MESH_Tunnel                   *tunnels_tail;
  91
  92     /**
  93      * tid of the next tunnel to create (to avoid reusing IDs often)
  94      */
  95     MESH_TunnelID                               next_tid;
  96
  97     /**
  98      * Callback for tunnel disconnection
  99      */
 100     GNUNET_MESH_TunnelEndHandler                *cleaner;
 101
 102     /**
 103      * Handle to cancel pending transmissions in case of disconnection
 104      */
 105     struct GNUNET_CLIENT_TransmitHandle         *th;
 106
 107     /**
 108      * Closure for all the handlers given by the client
 109      */
 110     void                                        *cls;
 111 };
 112
 113 /**
 114  * Opaque handle to a tunnel.
 115  */
 116 struct GNUNET_MESH_Tunnel {
 117
 118     /**
 119      * DLL
 120      */
 121     struct GNUNET_MESH_Tunnel                   *next;
 122     struct GNUNET_MESH_Tunnel                   *prev;
 123
 124     /**
 125      * Local ID of the tunnel
 126      */
 127     MESH_TunnelID                               tid;
 128
 129     /**
 130      * Callback to execute when peers connect to the tunnel
 131      */
 132     GNUNET_MESH_TunnelConnectHandler            connect_handler;
 133
 134     /**
 135      * Callback to execute when peers disconnect to the tunnel
 136      */
 137     GNUNET_MESH_TunnelDisconnectHandler         disconnect_handler;
 138
 139     /**
 140      * All peers added to the tunnel
 141      */
 142     GNUNET_PEER_Id                              *peers;
 143
 144     /**
 145      * Closure for the connect/disconnect handlers
 146      */
 147     void                                        *cls;
 148
 149     /**
 150      * Handle to the mesh this tunnel belongs to
 151      */
 152     struct GNUNET_MESH_Handle                   *mesh;
 153 };
 154
 155 struct GNUNET_MESH_TransmitHandle {
 156     // TODO
 157 };
 158
 159 /******************************************************************************/
 160 /***********************     AUXILIARY FUNCTIONS      *************************/
 161 /******************************************************************************/
 162
 163 /**
 164  * Get the tunnel handler for the tunnel specified by id from the given handle
 165  * @param h Mesh handle
 166  * @param tid ID of the wanted tunnel
 167  * @return handle to the required tunnel or NULL if not found
 168  */
 169 static struct GNUNET_MESH_Tunnel *
 170 retrieve_tunnel (struct GNUNET_MESH_Handle *h, MESH_TunnelID tid)
 171 {
 172     struct GNUNET_MESH_Tunnel           *t;
 173
 174     t = h->tunnels_head;
 175     while (t != NULL) {
 176         if (t->tid == tid) return t;
 177         t = t->next;
 178     }
 179     return NULL;
 180 }
 181
 182
 183 /******************************************************************************/
 184 /************************       SEND CALLBACKS     ****************************/
 185 /******************************************************************************/
 186
 187
 188 /**
 189  * Function called to send a connect message to the service, specifying the
 190  * types and applications that the client is interested in.
 191  * "buf" will be NULL and "size" zero if the socket was closed for writing in
 192  * the meantime.
 193  *
 194  * @param cls closure, the mesh handle
 195  * @param size number of bytes available in buf
 196  * @param buf where the callee should write the connect message
 197  * @return number of bytes written to buf
 198  */
 199 static size_t
 200 send_connect_packet (void *cls, size_t size, void *buf)
 201 {
 202     struct GNUNET_MESH_Handle           *h = cls;
 203     struct GNUNET_MESH_ClientConnect    *msg;
 204     uint16_t                            *types;
 205     uint16_t                            ntypes;
 206     GNUNET_MESH_ApplicationType         *apps;
 207     uint16_t                            napps;
 208
 209     h->th = NULL;
 210     if (0 == size || buf == NULL) {
 211         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 212                     "Send connect packet: buffer size 0 or buffer invalid\n");
 213         // FIXME: disconnect, reconnect, retry!
 214         return 0;
 215     }
 216     if (sizeof(struct GNUNET_MessageHeader) > size) {
 217         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 218                     "Send connect packet: buffer size too small\n");
 219         // FIXME: disconnect, reconnect, retry!
 220         return 0;
 221     }
 222     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 223                 "Send connect packet: %lu bytes buffer\n",
 224                 size);
 225     msg = (struct GNUNET_MESH_ClientConnect *) buf;
 226     msg->header.type = htons(GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT);
 227
 228     for (ntypes = 0, types = NULL; ntypes < h->n_handlers; ntypes++) {
 229         types = GNUNET_realloc(types, sizeof(uint16_t) * (ntypes + 1));
 230         types[ntypes] = h->message_handlers[ntypes].type;
 231     }
 232
 233     for(napps = 0, apps = NULL; napps < h->n_applications; napps++) {
 234         apps = GNUNET_realloc(apps,
 235                               sizeof(GNUNET_MESH_ApplicationType) *
 236                                 (napps + 1));
 237         apps[napps] = h->applications[napps];
 238     }
 239
 240     msg->header.size = htons(sizeof(struct GNUNET_MESH_ClientConnect) +
 241                              sizeof(uint16_t) * ntypes +
 242                              sizeof(GNUNET_MESH_ApplicationType) * napps);
 243
 244     memcpy(&msg[1], types, sizeof(uint16_t) * ntypes);
 245     memcpy(&msg[1] + sizeof(uint16_t) * ntypes,
 246            apps,
 247            sizeof(GNUNET_MESH_ApplicationType) * napps);
 248     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 249                 "Sent %lu bytes long message %d types and %d apps\n",
 250                 ntohs(msg->header.size),
 251                 ntypes,
 252                 napps
 253                );
 254     msg->applications = htons(napps);
 255     msg->types = htons(ntypes);
 256
 257     return ntohs(msg->header.size);
 258 }
 259
 260
 261 /**
 262  * Function called to send a create tunnel message, specifying the tunnel
 263  * number chosen by the client.
 264  * "buf" will be NULL and "size" zero if the socket was closed for
 265  * writing in the meantime.
 266  *
 267  * @param cls closure, the tunnel handle
 268  * @param size number of bytes available in buf
 269  * @param buf where the callee should write the create tunnel message
 270  * @return number of bytes written to buf
 271  */
 272 static size_t
 273 send_tunnel_create_packet (void *cls, size_t size, void *buf)
 274 {
 275     struct GNUNET_MESH_Tunnel           *t = cls;
 276     struct GNUNET_MESH_Handle           *h;
 277     struct GNUNET_MESH_TunnelMessage    *msg;
 278
 279     h = t->mesh;
 280     h->th = NULL;
 281     if (0 == size || buf == NULL) {
 282         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 283                     "Send connect packet: buffer size 0 or buffer invalid\n");
 284         // FIXME: disconnect, reconnect, retry!
 285         return 0;
 286     }
 287     if (sizeof(struct GNUNET_MessageHeader) > size) {
 288         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 289                     "Send connect packet: buffer size too small\n");
 290         // FIXME: disconnect, reconnect, retry!
 291         return 0;
 292     }
 293     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 294                 "Send connect packet: %lu bytes buffer\n",
 295                 size);
 296     msg = (struct GNUNET_MESH_TunnelMessage *) buf;
 297     msg->header.type = htons(GNUNET_MESSAGE_TYPE_MESH_LOCAL_CONNECT);
 298
 299     msg->header.size = htons(sizeof(struct GNUNET_MESH_TunnelMessage));
 300     msg->tunnel_id = htonl(t->tid);
 301
 302     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 303                 "Sent %lu bytes long message\n",
 304                 ntohs(msg->header.size));
 305
 306     return ntohs(msg->header.size);
 307 }
 308
 309
 310 /******************************************************************************/
 311 /***********************      RECEIVE HANDLERS     ****************************/
 312 /******************************************************************************/
 313
 314 /**
 315  * Process the new tunnel notification and add it to the tunnels in the handle
 316  *
 317  * @param h     The mesh handle
 318  * @param msh   A message with the details of the new incoming tunnel
 319  */
 320 static void
 321 process_tunnel_create(struct GNUNET_MESH_Handle *h,
 322                       const struct GNUNET_MESH_TunnelMessage *msg)
 323 {
 324     struct GNUNET_MESH_Tunnel                   *t;
 325     MESH_TunnelID                               tid;
 326
 327     tid = ntohl(msg->tunnel_id);
 328     if (tid >= GNUNET_MESH_LOCAL_TUNNEL_ID_MARK) {
 329         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 330             "MESH: received an incoming tunnel with tid in local range (%X)\n",
 331             tid);
 332         return; //FIXME abort? reconnect?
 333     }
 334     t = GNUNET_malloc(sizeof(struct GNUNET_MESH_Tunnel));
 335     t->cls = h->cls;
 336     t->connect_handler = NULL;
 337     t->disconnect_handler = NULL;
 338     t->mesh = h;
 339     t->tid = tid;
 340
 341     return;
 342 }
 343
 344
 345 /**
 346  * Process the incoming data packets
 347  *
 348  * @param h     The mesh handle
 349  * @param msh   A message encapsulating the data
 350  */
 351 static void
 352 process_incoming_data(struct GNUNET_MESH_Handle *h,
 353                       const struct GNUNET_MESH_Data *msg)
 354 {
 355     const struct GNUNET_MESH_Data               *payload;
 356     const struct GNUNET_MESH_MessageHandler     *handler;
 357     struct GNUNET_MESH_Tunnel                   *t;
 358     uint16_t                                    type;
 359     int                                         i;
 360
 361     t = retrieve_tunnel(h, ntohl(msg->tunnel_id));
 362
 363     payload = (struct GNUNET_MESH_Data *) &msg[1];
 364     type = ntohs(payload->header.type);
 365     for (i = 0; i < h->n_handlers; i++) {
 366         handler = &h->message_handlers[i];
 367         if (handler->type == type) {
 368             /* FIXME */
 369             if (GNUNET_OK == handler->callback (h->cls,
 370                                                 t,
 371                                                 NULL,
 372                                                 NULL,
 373                                                 NULL,
 374                                                 NULL))
 375             {
 376                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
 377                             "MESH: callback completed successfully\n");
 378             } else {
 379                 GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
 380                             "MESH: callback caused disconnection\n");
 381                 GNUNET_MESH_disconnect(h);
 382             }
 383         }
 384     }
 385     return;
 386 }
 387
 388
 389 /**
 390  * Function to process all messages received from the service
 391  *
 392  * @param cls closure
 393  * @param msg message received, NULL on timeout or fatal error
 394  */
 395 static void
 396 msg_received (void *cls, const struct GNUNET_MessageHeader * msg)
 397 {
 398     struct GNUNET_MESH_Handle                   *h = cls;
 399
 400     if (msg == NULL) {
 401         GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
 402                "received a NULL message from mesh\n");
 403         return;
 404     }
 405
 406     switch (ntohs(msg->type)) {
 407         /* Notify of a new incoming tunnel */
 408         case GNUNET_MESSAGE_TYPE_MESH_LOCAL_TUNNEL_CREATE:
 409             process_tunnel_create(h, (struct GNUNET_MESH_TunnelMessage *)msg);
 410             break;
 411         /* Notify of a new peer in the tunnel */
 412         case GNUNET_MESSAGE_TYPE_MESH_LOCAL_PEER_CONNECTED:
 413             break;
 414         /* Notify of a peer leaving the tunnel */
 415         case GNUNET_MESSAGE_TYPE_MESH_LOCAL_PEER_DISCONNECTED:
 416             break;
 417         /* Notify of a new data packet in the tunnel */
 418         case GNUNET_MESSAGE_TYPE_MESH_LOCAL_DATA:
 419             process_incoming_data(h, (struct GNUNET_MESH_Data *)msg);
 420             break;
 421         /* We shouldn't get any other packages, log and ignore */
 422         default:
 423             GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
 424                         "MESH: unsolicited message form service (type %d)\n",
 425                         ntohs(msg->type));
 426     }
 427
 428     GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
 429                "received a message from mesh\n");
 430     GNUNET_CLIENT_receive (h->client,
 431                         &msg_received,
 432                         h,
 433                         GNUNET_TIME_UNIT_FOREVER_REL);
 434     return;
 435 }
 436
 437 /******************************************************************************/
 438 /**********************      API CALL DEFINITIONS     *************************/
 439 /******************************************************************************/
 440
 441 /**
 442  * Connect to the mesh service.
 443  *
 444  * @param cfg configuration to use
 445  * @param cls closure for the various callbacks that follow
 446  *            (including handlers in the handlers array)
 447  * @param cleaner function called when an *inbound* tunnel is destroyed
 448  * @param handlers callbacks for messages we care about, NULL-terminated
 449  *                 note that the mesh is allowed to drop notifications about
 450  *                 inbound messages if the client does not process them fast
 451  *                 enough (for this notification type, a bounded queue is used)
 452  * @param stypes Application Types the client claims to offer
 453  * @return handle to the mesh service
 454  *         NULL on error (in this case, init is never called)
 455  */
 456 struct GNUNET_MESH_Handle *
 457 GNUNET_MESH_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
 458                      void *cls,
 459                      GNUNET_MESH_TunnelEndHandler cleaner,
 460                      const struct GNUNET_MESH_MessageHandler *handlers,
 461                      const GNUNET_MESH_ApplicationType *stypes)
 462 {
 463     struct GNUNET_MESH_Handle           *h;
 464     size_t                              size;
 465
 466     h = GNUNET_malloc(sizeof(struct GNUNET_MESH_Handle));
 467
 468     h->cleaner = cleaner;
 469     h->client = GNUNET_CLIENT_connect("mesh", cfg);
 470     GNUNET_CLIENT_receive (h->client,
 471                          &msg_received,
 472                          h,
 473                          GNUNET_TIME_UNIT_FOREVER_REL);
 474     if(h->client == NULL) {
 475         GNUNET_free(h);
 476         return NULL;
 477     }
 478
 479     h->cls = cls;
 480     h->message_handlers = handlers;
 481     h->applications = stypes;
 482     h->next_tid = 0x80000000;
 483
 484     for(h->n_handlers = 0; handlers[h->n_handlers].type; h->n_handlers++);
 485     for(h->n_applications = 0; stypes[h->n_applications]; h->n_applications++);
 486
 487     size = sizeof(struct GNUNET_MESH_ClientConnect);
 488     size += h->n_handlers * sizeof(uint16_t);
 489     size += h->n_applications * sizeof(GNUNET_MESH_ApplicationType);
 490
 491     h->th = GNUNET_CLIENT_notify_transmit_ready(h->client,
 492                                                 size,
 493                                                 GNUNET_TIME_UNIT_FOREVER_REL,
 494                                                 GNUNET_YES,
 495                                                 &send_connect_packet,
 496                                                 (void *)h);
 497
 498     return h;
 499 }
 500
 501
 502 /**
 503  * Disconnect from the mesh service.
 504  *
 505  * @param handle connection to mesh to disconnect
 506  */
 507 void
 508 GNUNET_MESH_disconnect (struct GNUNET_MESH_Handle *handle)
 509 {
 510     if (NULL != handle->th) {
 511         GNUNET_CLIENT_notify_transmit_ready_cancel (handle->th);
 512     }
 513     if (NULL != handle->client) {
 514         GNUNET_CLIENT_disconnect (handle->client, GNUNET_NO);
 515     }
 516     GNUNET_free(handle);
 517 }
 518
 519
 520 /**
 521  * Create a new tunnel (we're initiator and will be allowed to add/remove peers
 522  * and to broadcast).
 523  *
 524  * @param h mesh handle
 525  * @param connect_handler function to call when peers are actually connected
 526  * @param disconnect_handler function to call when peers are disconnected
 527  * @param handler_cls closure for connect/disconnect handlers
 528  */
 529 struct GNUNET_MESH_Tunnel *
 530 GNUNET_MESH_tunnel_create (struct GNUNET_MESH_Handle *h,
 531                            GNUNET_MESH_TunnelConnectHandler
 532                            connect_handler,
 533                            GNUNET_MESH_TunnelDisconnectHandler
 534                            disconnect_handler,
 535                            void *handler_cls)
 536 {
 537     struct GNUNET_MESH_Tunnel           *tunnel;
 538
 539     GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
 540                "MESH: Creating new tunnel\n");
 541     tunnel = GNUNET_malloc(sizeof(struct GNUNET_MESH_Tunnel));
 542
 543     tunnel->connect_handler = connect_handler;
 544     tunnel->disconnect_handler = disconnect_handler;
 545     tunnel->cls = handler_cls;
 546     tunnel->mesh = h;
 547     tunnel->tid = h->next_tid++;
 548     h->next_tid |= GNUNET_MESH_LOCAL_TUNNEL_ID_MARK; // keep in range
 549
 550     h->th = GNUNET_CLIENT_notify_transmit_ready(h->client,
 551                                     sizeof(struct GNUNET_MESH_TunnelMessage),
 552                                     GNUNET_TIME_UNIT_FOREVER_REL,
 553                                     GNUNET_YES,
 554                                     &send_tunnel_create_packet,
 555                                     (void *)tunnel);
 556
 557     return tunnel;
 558 }
 559
 560
 561 /**
 562  * Request that a peer should be added to the tunnel.  The existing
 563  * connect handler will be called ONCE with either success or failure.
 564  *
 565  * @param tunnel handle to existing tunnel
 566  * @param timeout how long to try to establish a connection
 567  * @param peer peer to add
 568  */
 569 void
 570 GNUNET_MESH_peer_request_connect_add (struct GNUNET_MESH_Tunnel *tunnel,
 571                                       struct GNUNET_TIME_Relative timeout,
 572                                       const struct GNUNET_PeerIdentity *peer)
 573 {
 574     static GNUNET_PEER_Id       peer_id;
 575
 576     peer_id = GNUNET_PEER_intern(peer);
 577
 578     /* FIXME ACTUALLY DO STUFF */
 579     tunnel->peers = &peer_id;
 580     tunnel->connect_handler(tunnel->cls, peer, NULL);
 581     return;
 582 }
 583
 584
 585 /**
 586  * Request that a peer should be removed from the tunnel.  The existing
 587  * disconnect handler will be called ONCE if we were connected.
 588  *
 589  * @param tunnel handle to existing tunnel
 590  * @param peer peer to remove
 591  */
 592 void
 593 GNUNET_MESH_peer_request_connect_del (struct GNUNET_MESH_Tunnel *tunnel,
 594                                       const struct GNUNET_PeerIdentity *peer)
 595 {
 596     /* FIXME ACTUALLY DO STUFF */
 597     tunnel->peers = NULL;
 598     tunnel->disconnect_handler(tunnel->cls, peer);
 599     return;
 600 }
 601
 602
 603 /**
 604  * Request that the mesh should try to connect to a peer supporting the given
 605  * message type.
 606  *
 607  * @param tunnel handle to existing tunnel
 608  * @param timeout how long to try to establish a connection
 609  * @param app_type application type that must be supported by the peer (MESH
 610  *                 should discover peer in proximity handling this type)
 611  */
 612 void
 613 GNUNET_MESH_peer_request_connect_by_type (struct GNUNET_MESH_Tunnel *tunnel,
 614                                           struct GNUNET_TIME_Relative timeout,
 615                                           GNUNET_MESH_ApplicationType
 616                                           app_type)
 617 {
 618     return;
 619 }
 620
 621
 622 /**
 623  * Ask the mesh to call "notify" once it is ready to transmit the
 624  * given number of bytes to the specified "target".  If we are not yet
 625  * connected to the specified peer, a call to this function will cause
 626  * us to try to establish a connection.
 627  *
 628  * @param tunnel tunnel to use for transmission
 629  * @param cork is corking allowed for this transmission?
 630  * @param priority how important is the message?
 631  * @param maxdelay how long can the message wait?
 632  * @param target destination for the message,
 633  *               NULL for multicast to all tunnel targets
 634  * @param notify_size how many bytes of buffer space does notify want?
 635  * @param notify function to call when buffer space is available;
 636  *        will be called with NULL on timeout or if the overall queue
 637  *        for this peer is larger than queue_size and this is currently
 638  *        the message with the lowest priority
 639  * @param notify_cls closure for notify
 640  * @return non-NULL if the notify callback was queued,
 641  *         NULL if we can not even queue the request (insufficient
 642  *         memory); if NULL is returned, "notify" will NOT be called.
 643  */
 644 struct GNUNET_MESH_TransmitHandle *
 645 GNUNET_MESH_notify_transmit_ready (struct GNUNET_MESH_Tunnel *tunnel,
 646                                    int cork,
 647                                    uint32_t priority,
 648                                    struct GNUNET_TIME_Relative maxdelay,
 649                                    const struct GNUNET_PeerIdentity *target,
 650                                    size_t notify_size,
 651                                    GNUNET_CONNECTION_TransmitReadyNotify
 652                                    notify,
 653                                    void *notify_cls)
 654 {
 655     struct GNUNET_MESH_TransmitHandle   *handle;
 656
 657     handle = GNUNET_malloc(sizeof(struct GNUNET_MESH_TransmitHandle));
 658
 659     return handle;
 660 }
 661
 662
 663 #if 0                           /* keep Emacsens' auto-indent happy */
 664 {
 665 #endif
 666 #ifdef __cplusplus
 667 }
 668 #endif