2 This file is part of GNUnet.
3 (C) 2009 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file util/connection.c
23 * @brief TCP connection management
24 * @author Christian Grothoff
26 * This code is rather complex. Only modify it if you
27 * 1) Have a NEW testcase showing that the new code
28 * is needed and correct
29 * 2) All EXISTING testcases pass with the new code
30 * These rules should apply in general, but for this
31 * module they are VERY, VERY important.
35 #include "gnunet_common.h"
36 #include "gnunet_connection_lib.h"
37 #include "gnunet_container_lib.h"
38 #include "gnunet_resolver_service.h"
39 #include "gnunet_scheduler_lib.h"
41 #define DEBUG_CONNECTION GNUNET_NO
45 * Possible functions to call after connect failed or succeeded.
47 enum ConnectContinuations
55 * Call "receive_again".
57 COCO_RECEIVE_AGAIN = 1,
60 * Call "transmit_ready".
62 COCO_TRANSMIT_READY = 2,
65 * Call "destroy_continuation".
67 COCO_DESTROY_CONTINUATION = 4
72 * Transmission handle. There can only be one for each connection.
74 struct GNUNET_CONNECTION_TransmitHandle
78 * Function to call if the send buffer has notify_size
81 GNUNET_CONNECTION_TransmitReadyNotify notify_ready;
84 * Closure for notify_ready.
86 void *notify_ready_cls;
91 struct GNUNET_CONNECTION_Handle *sh;
94 * Timeout for receiving (in absolute time).
96 struct GNUNET_TIME_Absolute transmit_timeout;
99 * Task called on timeout.
101 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
104 * At what number of bytes available in the
105 * write buffer should the notify method be called?
113 * During connect, we try multiple possible IP addresses
114 * to find out which one might work.
120 * This is a linked list.
122 struct AddressProbe *next;
125 * This is a doubly-linked list.
127 struct AddressProbe *prev;
130 * The address; do not free (allocated at the end of this struct).
132 const struct sockaddr *addr;
135 * Underlying OS's socket.
137 struct GNUNET_NETWORK_Handle *sock;
140 * Connection for which we are probing.
142 struct GNUNET_CONNECTION_Handle *h;
150 * Task waiting for the socket to finish connecting.
152 GNUNET_SCHEDULER_TaskIdentifier task;
157 * @brief handle for a network socket
159 struct GNUNET_CONNECTION_Handle
163 * Scheduler that was used for the connect task.
165 struct GNUNET_SCHEDULER_Handle *sched;
168 * Configuration to use.
170 const struct GNUNET_CONFIGURATION_Handle *cfg;
173 * Linked list of sockets we are currently trying out
176 struct AddressProbe *ap_head;
179 * Linked list of sockets we are currently trying out
182 struct AddressProbe *ap_tail;
185 * Network address of the other end-point, may be NULL.
187 struct sockaddr *addr;
190 * Pointer to the hostname if socket was
191 * created using DNS lookup, otherwise NULL.
196 * Underlying OS's socket, set to NULL after fatal errors.
198 struct GNUNET_NETWORK_Handle *sock;
201 * Function to call on data received, NULL if no receive is pending.
203 GNUNET_CONNECTION_Receiver receiver;
206 * Closure for receiver.
211 * Pointer to our write buffer.
216 * Size of our write buffer.
218 size_t write_buffer_size;
221 * Current write-offset in write buffer (where
222 * would we write next).
224 size_t write_buffer_off;
227 * Current read-offset in write buffer (how many
228 * bytes have already been send).
230 size_t write_buffer_pos;
238 * Read task that we may need to wait for.
240 GNUNET_SCHEDULER_TaskIdentifier read_task;
243 * Write task that we may need to wait for.
245 GNUNET_SCHEDULER_TaskIdentifier write_task;
248 * Destroy task (if already scheduled).
250 GNUNET_SCHEDULER_TaskIdentifier destroy_task;
253 * Handle to a pending DNS lookup request.
255 struct GNUNET_RESOLVER_RequestHandle *dns_active;
258 * The handle we return for GNUNET_CONNECTION_notify_transmit_ready.
260 struct GNUNET_CONNECTION_TransmitHandle nth;
263 * Timeout for receiving (in absolute time).
265 struct GNUNET_TIME_Absolute receive_timeout;
268 * Functions to call after connect failed or succeeded.
270 enum ConnectContinuations ccs;
273 * Maximum number of bytes to read (for receiving).
278 * Ignore GNUNET_SCHEDULER_REASON_SHUTDOWN for this socket.
283 * Port to connect to.
288 * When shutdown, do not ever actually close the socket, but
289 * free resources. Only should ever be set if using program
290 * termination as a signal (because only then will the leaked
298 * Set the persist option on this connection handle. Indicates
299 * that the underlying socket or fd should never really be closed.
300 * Used for indicating process death.
302 * @param sock the connection to set persistent
304 void GNUNET_CONNECTION_persist_(struct GNUNET_CONNECTION_Handle *sock)
306 sock->persist = GNUNET_YES;
310 * Create a socket handle by boxing an existing OS socket. The OS
311 * socket should henceforth be no longer used directly.
312 * GNUNET_socket_destroy will close it.
314 * @param sched scheduler to use
315 * @param osSocket existing socket to box
316 * @param maxbuf maximum write buffer size for the socket (use
317 * 0 for sockets that need no write buffers, such as listen sockets)
318 * @return the boxed socket handle
320 struct GNUNET_CONNECTION_Handle *
321 GNUNET_CONNECTION_create_from_existing (struct GNUNET_SCHEDULER_Handle
323 struct GNUNET_NETWORK_Handle
324 *osSocket, size_t maxbuf)
326 struct GNUNET_CONNECTION_Handle *ret;
327 ret = GNUNET_malloc (sizeof (struct GNUNET_CONNECTION_Handle) + maxbuf);
328 ret->write_buffer = (char *) &ret[1];
329 ret->write_buffer_size = maxbuf;
330 ret->sock = osSocket;
337 * Create a socket handle by accepting on a listen socket. This
338 * function may block if the listen socket has no connection ready.
340 * @param sched scheduler to use
341 * @param access function to use to check if access is allowed
342 * @param access_cls closure for access
343 * @param lsock listen socket
344 * @param maxbuf maximum write buffer size for the socket (use
345 * 0 for sockets that need no write buffers, such as listen sockets)
346 * @return the socket handle, NULL on error
348 struct GNUNET_CONNECTION_Handle *
349 GNUNET_CONNECTION_create_from_accept (struct GNUNET_SCHEDULER_Handle
351 GNUNET_CONNECTION_AccessCheck access,
353 struct GNUNET_NETWORK_Handle *lsock,
356 struct GNUNET_CONNECTION_Handle *ret;
359 struct GNUNET_NETWORK_Handle *sock;
361 struct sockaddr_in *v4;
362 struct sockaddr_in6 *v6;
366 addrlen = sizeof (addr);
368 GNUNET_NETWORK_socket_accept (lsock, (struct sockaddr *) &addr, &addrlen);
371 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "accept");
374 if (addrlen > sizeof (addr))
377 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
381 sa = (struct sockaddr *) addr;
382 v6 = (struct sockaddr_in6 *) addr;
383 if ((sa->sa_family == AF_INET6) && (IN6_IS_ADDR_V4MAPPED (&v6->sin6_addr)))
385 /* convert to V4 address */
386 v4 = GNUNET_malloc (sizeof (struct sockaddr_in));
387 memset (v4, 0, sizeof (struct sockaddr_in));
388 v4->sin_family = AF_INET;
389 memcpy (&v4->sin_addr,
390 &((char *) &v6->sin6_addr)[sizeof (struct in6_addr) -
391 sizeof (struct in_addr)],
392 sizeof (struct in_addr));
393 v4->sin_port = v6->sin6_port;
395 addrlen = sizeof (struct sockaddr_in);
399 uaddr = GNUNET_malloc (addrlen);
400 memcpy (uaddr, addr, addrlen);
403 if ((access != NULL) &&
404 (GNUNET_YES != (aret = access (access_cls, uaddr, addrlen))))
406 if (aret == GNUNET_NO)
407 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
408 _("Access denied to `%s'\n"),
409 GNUNET_a2s (uaddr, addrlen));
410 GNUNET_break (GNUNET_OK ==
411 GNUNET_NETWORK_socket_shutdown (sock, SHUT_RDWR));
412 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
416 ret = GNUNET_malloc (sizeof (struct GNUNET_CONNECTION_Handle) + maxbuf);
417 ret->write_buffer = (char *) &ret[1];
418 ret->write_buffer_size = maxbuf;
420 ret->addrlen = addrlen;
424 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
425 _("Accepting connection from `%s': %p\n"),
426 GNUNET_a2s (uaddr, addrlen), ret);
432 * Obtain the network address of the other party.
434 * @param sock the client to get the address for
435 * @param addr where to store the address
436 * @param addrlen where to store the length of the address
437 * @return GNUNET_OK on success
440 GNUNET_CONNECTION_get_address (struct GNUNET_CONNECTION_Handle *sock,
441 void **addr, size_t * addrlen)
443 if ((sock->addr == NULL) || (sock->addrlen == 0))
445 *addr = GNUNET_malloc (sock->addrlen);
446 memcpy (*addr, sock->addr, sock->addrlen);
447 *addrlen = sock->addrlen;
453 * This function is called after establishing a connection either has
454 * succeeded or timed out. Note that it is possible that the attempt
455 * timed out and that we're immediately retrying. If we are retrying,
456 * we need to wait again (or timeout); if we succeeded, we need to
457 * wait for data (or timeout).
459 * @param cls our connection handle
460 * @param tc task context describing why we are here
463 receive_again (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
467 * Scheduler let us know that the connect task is finished (or was
468 * cancelled due to shutdown). Now really clean up.
470 * @param cls our "struct GNUNET_CONNECTION_Handle *"
474 destroy_continuation (void *cls,
475 const struct GNUNET_SCHEDULER_TaskContext *tc)
477 struct GNUNET_CONNECTION_Handle *sock = cls;
478 GNUNET_CONNECTION_TransmitReadyNotify notify;
479 struct AddressProbe *pos;
481 sock->destroy_task = GNUNET_SCHEDULER_NO_TASK;
482 GNUNET_assert (sock->dns_active == NULL);
483 if (0 != (sock->ccs & COCO_TRANSMIT_READY))
486 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
487 "Destroy waits for CCS-TR to be done (%p)\n", sock);
489 sock->ccs |= COCO_DESTROY_CONTINUATION;
492 if (sock->write_task != GNUNET_SCHEDULER_NO_TASK)
495 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
496 "Destroy waits for write_task to be done (%p)\n", sock);
498 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == sock->destroy_task);
500 = GNUNET_SCHEDULER_add_after (sock->sched,
502 &destroy_continuation, sock);
505 if (0 != (sock->ccs & COCO_RECEIVE_AGAIN))
507 sock->ccs |= COCO_DESTROY_CONTINUATION;
510 if (sock->sock != NULL)
513 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
514 "Shutting down socket (%p)\n", sock);
516 if (sock->persist != GNUNET_YES)
517 GNUNET_NETWORK_socket_shutdown (sock->sock, SHUT_RDWR);
519 if (sock->read_task != GNUNET_SCHEDULER_NO_TASK)
521 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == sock->destroy_task);
523 = GNUNET_SCHEDULER_add_after (sock->sched,
525 &destroy_continuation, sock);
529 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
530 "Destroy actually runs (%p)!\n", sock);
532 if (sock->dns_active != NULL)
534 GNUNET_RESOLVER_request_cancel (sock->dns_active);
535 sock->dns_active = NULL;
537 while (NULL != (pos = sock->ap_head))
539 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (pos->sock));
540 GNUNET_SCHEDULER_cancel (sock->sched, pos->task);
541 GNUNET_CONTAINER_DLL_remove (sock->ap_head, sock->ap_tail, pos);
544 GNUNET_assert (sock->nth.timeout_task == GNUNET_SCHEDULER_NO_TASK);
545 GNUNET_assert (sock->ccs == COCO_NONE);
546 if (NULL != (notify = sock->nth.notify_ready))
548 sock->nth.notify_ready = NULL;
549 notify (sock->nth.notify_ready_cls, 0, NULL);
552 if (sock->sock != NULL)
554 if (sock->persist != GNUNET_YES)
555 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock->sock));
557 GNUNET_free (sock->sock); /* at least no memory leak (we deliberately
558 leak the socket in this special case) ... */
560 GNUNET_free_non_null (sock->addr);
561 GNUNET_free_non_null (sock->hostname);
562 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == sock->destroy_task);
564 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
565 "Freeing memory of connection %p.\n", sock);
573 * See if we are now connected. If not, wait longer for
574 * connect to succeed. If connected, we should be able
575 * to write now as well, unless we timed out.
577 * @param cls our connection handle
578 * @param tc task context describing why we are here
581 transmit_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
585 * We've failed for good to establish a connection.
587 * @param h the connection we tried to establish
590 connect_fail_continuation (struct GNUNET_CONNECTION_Handle *h)
592 GNUNET_log ((0 != strncmp (h->hostname,
595 ? GNUNET_ERROR_TYPE_INFO
596 : GNUNET_ERROR_TYPE_WARNING,
597 _("Failed to establish TCP connection to `%s:%u', no further addresses to try.\n"),
598 h->hostname, h->port);
599 /* connect failed / timed out */
600 GNUNET_break (h->ap_head == NULL);
601 GNUNET_break (h->ap_tail == NULL);
602 GNUNET_break (h->dns_active == GNUNET_NO);
603 GNUNET_break (h->sock == NULL);
605 /* trigger jobs that used to wait on "connect_task" */
606 if (0 != (h->ccs & COCO_RECEIVE_AGAIN))
609 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
610 "connect_fail_continuation triggers receive_again (%p)\n",
613 h->ccs -= COCO_RECEIVE_AGAIN;
614 h->read_task = GNUNET_SCHEDULER_add_after (h->sched,
615 GNUNET_SCHEDULER_NO_TASK,
618 if (0 != (h->ccs & COCO_TRANSMIT_READY))
621 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
622 "connect_fail_continuation cancels timeout_task, triggers transmit_ready (%p)\n",
625 GNUNET_assert (h->nth.timeout_task != GNUNET_SCHEDULER_NO_TASK);
626 GNUNET_SCHEDULER_cancel (h->sched, h->nth.timeout_task);
627 h->nth.timeout_task = GNUNET_SCHEDULER_NO_TASK;
628 h->ccs -= COCO_TRANSMIT_READY;
629 h->write_task = GNUNET_SCHEDULER_add_after (h->sched,
630 GNUNET_SCHEDULER_NO_TASK,
633 if (0 != (h->ccs & COCO_DESTROY_CONTINUATION))
636 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
637 "connect_fail_continuation runs destroy_continuation (%p)\n",
640 h->ccs -= COCO_DESTROY_CONTINUATION;
641 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == h->destroy_task);
643 = GNUNET_SCHEDULER_add_now (h->sched,
644 &destroy_continuation,
651 * We've succeeded in establishing a connection.
653 * @param h the connection we tried to establish
656 connect_success_continuation (struct GNUNET_CONNECTION_Handle *h)
659 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
660 "Connection to `%s' succeeded! (%p)\n",
661 GNUNET_a2s (h->addr, h->addrlen), h);
663 /* trigger jobs that waited for the connection */
664 if (0 != (h->ccs & COCO_RECEIVE_AGAIN))
667 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
668 "connect_success_continuation runs receive_again (%p)\n",
671 h->ccs -= COCO_RECEIVE_AGAIN;
672 h->read_task = GNUNET_SCHEDULER_add_after (h->sched,
673 GNUNET_SCHEDULER_NO_TASK,
676 if (0 != (h->ccs & COCO_TRANSMIT_READY))
679 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
680 "connect_success_continuation runs transmit_ready, cancels timeout_task (%p)\n",
683 GNUNET_assert (h->nth.timeout_task != GNUNET_SCHEDULER_NO_TASK);
684 GNUNET_SCHEDULER_cancel (h->sched, h->nth.timeout_task);
685 h->nth.timeout_task = GNUNET_SCHEDULER_NO_TASK;
686 h->ccs -= COCO_TRANSMIT_READY;
688 GNUNET_SCHEDULER_add_write_net (h->sched,
689 GNUNET_TIME_absolute_get_remaining
690 (h->nth.transmit_timeout), h->sock,
693 if (0 != (h->ccs & COCO_DESTROY_CONTINUATION))
696 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
697 "connect_success_continuation runs destroy_continuation (%p)\n",
700 h->ccs -= COCO_DESTROY_CONTINUATION;
701 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == h->destroy_task);
703 = GNUNET_SCHEDULER_add_now (h->sched,
704 &destroy_continuation,
711 * Scheduler let us know that we're either ready to write on the
712 * socket OR connect timed out. Do the right thing.
714 * @param cls the "struct AddressProbe*" with the address that we are probing
715 * @param tc success or failure info about the connect attempt.
718 connect_probe_continuation (void *cls,
719 const struct GNUNET_SCHEDULER_TaskContext *tc)
721 struct AddressProbe *ap = cls;
722 struct GNUNET_CONNECTION_Handle *h = ap->h;
723 struct AddressProbe *pos;
727 GNUNET_CONTAINER_DLL_remove (h->ap_head, h->ap_tail, ap);
728 len = sizeof (error);
731 if ((0 == (tc->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) ||
733 GNUNET_NETWORK_socket_getsockopt (ap->sock, SOL_SOCKET, SO_ERROR,
734 &error, &len)) || (error != 0)
737 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (ap->sock));
739 if ((NULL == h->ap_head) && (h->dns_active == GNUNET_NO))
740 connect_fail_continuation (h);
743 GNUNET_assert (h->sock == NULL);
744 GNUNET_assert (ap->sock != NULL);
746 GNUNET_assert (h->addr == NULL);
747 h->addr = GNUNET_malloc (ap->addrlen);
748 memcpy (h->addr, ap->addr, ap->addrlen);
749 h->addrlen = ap->addrlen;
751 /* cancel all other attempts */
752 while (NULL != (pos = h->ap_head))
754 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (pos->sock));
755 GNUNET_SCHEDULER_cancel (h->sched, pos->task);
756 GNUNET_CONTAINER_DLL_remove (h->ap_head, h->ap_tail, pos);
759 connect_success_continuation (h);
764 * Try to establish a socket connection given the specified address.
765 * This function is called by the resolver once we have a DNS reply.
767 * @param cls our "struct GNUNET_CONNECTION_Handle *"
768 * @param addr address to try, NULL for "last call"
769 * @param addrlen length of addr
772 try_connect_using_address (void *cls,
773 const struct sockaddr *addr, socklen_t addrlen)
775 struct GNUNET_CONNECTION_Handle *h = cls;
776 struct AddressProbe *ap;
777 struct GNUNET_TIME_Relative delay;
781 h->dns_active = NULL;
782 if (NULL == h->ap_head)
783 connect_fail_continuation (h);
787 return; /* already connected */
788 GNUNET_assert (h->addr == NULL);
791 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
792 "Trying to connect using address `%s:%u/%s:%u'\n",
793 h->hostname, h->port, GNUNET_a2s (addr, addrlen), h->port);
795 ap = GNUNET_malloc (sizeof (struct AddressProbe) + addrlen);
796 ap->addr = (const struct sockaddr *) &ap[1];
797 memcpy (&ap[1], addr, addrlen);
798 ap->addrlen = addrlen;
801 switch (ap->addr->sa_family)
804 ((struct sockaddr_in *) ap->addr)->sin_port = htons (h->port);
807 ((struct sockaddr_in6 *) ap->addr)->sin6_port = htons (h->port);
812 return; /* not supported by us */
815 GNUNET_NETWORK_socket_create (ap->addr->sa_family, SOCK_STREAM, 0);
816 if (ap->sock == NULL)
819 return; /* not supported by OS */
821 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
822 _("Trying to connect to `%s' (%p)\n"),
823 GNUNET_a2s (ap->addr, ap->addrlen), h);
824 if ((GNUNET_OK != GNUNET_NETWORK_socket_connect (ap->sock,
827 (errno != EINPROGRESS))
829 /* maybe refused / unsupported address, try next */
830 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "connect");
831 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (ap->sock));
835 GNUNET_CONTAINER_DLL_insert (h->ap_head, h->ap_tail, ap);
836 delay = GNUNET_CONNECTION_CONNECT_RETRY_TIMEOUT;
837 if (h->nth.notify_ready != NULL)
838 delay = GNUNET_TIME_relative_min (delay,
839 GNUNET_TIME_absolute_get_remaining
840 (h->nth.transmit_timeout));
841 if (h->receiver != NULL)
842 delay = GNUNET_TIME_relative_min (delay,
843 GNUNET_TIME_absolute_get_remaining
844 (h->receive_timeout));
846 GNUNET_SCHEDULER_add_write_net (h->sched, delay, ap->sock,
847 &connect_probe_continuation, ap);
852 * Create a socket handle by (asynchronously) connecting to a host.
853 * This function returns immediately, even if the connection has not
854 * yet been established. This function only creates TCP connections.
856 * @param sched scheduler to use
857 * @param cfg configuration to use
858 * @param hostname name of the host to connect to
859 * @param port port to connect to
860 * @param maxbuf maximum write buffer size for the socket (use
861 * 0 for sockets that need no write buffers, such as listen sockets)
862 * @return the socket handle
864 struct GNUNET_CONNECTION_Handle *
865 GNUNET_CONNECTION_create_from_connect (struct GNUNET_SCHEDULER_Handle *sched,
867 GNUNET_CONFIGURATION_Handle *cfg,
868 const char *hostname, uint16_t port,
871 struct GNUNET_CONNECTION_Handle *ret;
873 GNUNET_assert (0 < strlen (hostname)); /* sanity check */
874 ret = GNUNET_malloc (sizeof (struct GNUNET_CONNECTION_Handle) + maxbuf);
877 ret->write_buffer = (char *) &ret[1];
878 ret->write_buffer_size = maxbuf;
880 ret->hostname = GNUNET_strdup (hostname);
881 ret->dns_active = GNUNET_RESOLVER_ip_get (sched,
885 GNUNET_CONNECTION_CONNECT_RETRY_TIMEOUT,
886 &try_connect_using_address, ret);
892 * Create a socket handle by connecting to a UNIX domain service.
893 * This function returns immediately, even if the connection has not
894 * yet been established. This function only creates UNIX connections.
896 * @param sched scheduler to use
897 * @param cfg configuration to use
898 * @param unixpath path to connect to
899 * @param maxbuf maximum write buffer size for the socket (use
900 * 0 for sockets that need no write buffers, such as listen sockets)
901 * @return the socket handle, NULL on systems without UNIX support
903 struct GNUNET_CONNECTION_Handle *
904 GNUNET_CONNECTION_create_from_connect_to_unixpath (struct GNUNET_SCHEDULER_Handle *sched,
906 GNUNET_CONFIGURATION_Handle *cfg,
907 const char *unixpath,
911 struct GNUNET_CONNECTION_Handle *ret;
912 struct sockaddr_un *un;
915 GNUNET_assert (0 < strlen (unixpath)); /* sanity check */
916 un = GNUNET_malloc (sizeof (struct sockaddr_un));
917 un->sun_family = AF_UNIX;
918 slen = strlen (unixpath) + 1;
919 if (slen >= sizeof (un->sun_path))
920 slen = sizeof (un->sun_path) - 1;
921 memcpy (un->sun_path,
924 un->sun_path[slen] = '\0';
925 slen += sizeof (sa_family_t);
927 un->sun_path[0] = '\0';
928 slen = sizeof (struct sockaddr_un);
930 ret = GNUNET_malloc (sizeof (struct GNUNET_CONNECTION_Handle) + maxbuf);
933 ret->write_buffer = (char *) &ret[1];
934 ret->write_buffer_size = maxbuf;
936 ret->hostname = NULL;
937 ret->addr = (struct sockaddr*) un;
939 ret->sock = GNUNET_NETWORK_socket_create (AF_UNIX, SOCK_STREAM, 0);
940 if (NULL == ret->sock)
946 if (GNUNET_OK != GNUNET_NETWORK_socket_connect (ret->sock,
950 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (ret->sock));
951 GNUNET_free (ret->addr);
955 connect_success_continuation (ret);
964 * Create a socket handle by (asynchronously) connecting to a host.
965 * This function returns immediately, even if the connection has not
966 * yet been established. This function only creates TCP connections.
968 * @param sched scheduler to use
969 * @param af_family address family to use
970 * @param serv_addr server address
971 * @param addrlen length of server address
972 * @param maxbuf maximum write buffer size for the socket (use
973 * 0 for sockets that need no write buffers, such as listen sockets)
974 * @return the socket handle
976 struct GNUNET_CONNECTION_Handle *
977 GNUNET_CONNECTION_create_from_sockaddr (struct GNUNET_SCHEDULER_Handle
978 *sched, int af_family,
979 const struct sockaddr *serv_addr,
980 socklen_t addrlen, size_t maxbuf)
982 struct GNUNET_NETWORK_Handle *s;
983 struct GNUNET_CONNECTION_Handle *ret;
985 s = GNUNET_NETWORK_socket_create (af_family, SOCK_STREAM, 0);
988 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING |
989 GNUNET_ERROR_TYPE_BULK, "socket");
992 if ((GNUNET_OK != GNUNET_NETWORK_socket_connect (s, serv_addr, addrlen))
993 && (errno != EINPROGRESS))
995 /* maybe refused / unsupported address, try next */
996 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "connect");
997 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (s));
1000 ret = GNUNET_CONNECTION_create_from_existing (sched, s, maxbuf);
1001 ret->addr = GNUNET_malloc (addrlen);
1002 memcpy (ret->addr, serv_addr, addrlen);
1003 ret->addrlen = addrlen;
1004 #if DEBUG_CONNECTION
1005 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1006 _("Trying to connect to `%s' (%p)\n"),
1007 GNUNET_a2s (serv_addr, addrlen), ret);
1014 * Check if socket is valid (no fatal errors have happened so far).
1015 * Note that a socket that is still trying to connect is considered
1018 * @param sock socket to check
1019 * @return GNUNET_YES if valid, GNUNET_NO otherwise
1022 GNUNET_CONNECTION_check (struct GNUNET_CONNECTION_Handle *sock)
1024 if ((sock->ap_head != NULL) || (sock->dns_active != NULL))
1025 return GNUNET_YES; /* still trying to connect */
1026 return (sock->sock == NULL) ? GNUNET_NO : GNUNET_YES;
1031 * Close the socket and free associated resources. Pending
1032 * transmissions may be completed or dropped depending on the
1033 * arguments. If a receive call is pending and should
1034 * NOT be completed, 'GNUNET_CONNECTION_receive_cancel'
1035 * should be called explicitly first.
1037 * @param sock socket to destroy
1038 * @param finish_pending_write should pending writes be completed or aborted?
1039 * (this applies to transmissions where the data has already been
1040 * read from the application; all other transmissions should be
1041 * aborted using 'GNUNET_CONNECTION_notify_transmit_ready_cancel').
1044 GNUNET_CONNECTION_destroy (struct GNUNET_CONNECTION_Handle *sock,
1045 int finish_pending_write)
1047 if (GNUNET_NO == finish_pending_write)
1049 if (sock->write_task != GNUNET_SCHEDULER_NO_TASK)
1051 GNUNET_SCHEDULER_cancel (sock->sched,
1053 sock->write_task = GNUNET_SCHEDULER_NO_TASK;
1054 sock->write_buffer_off = 0;
1057 if ((sock->write_buffer_off == 0) && (sock->dns_active != NULL))
1059 GNUNET_RESOLVER_request_cancel (sock->dns_active);
1060 sock->dns_active = NULL;
1062 GNUNET_assert (sock->sched != NULL);
1063 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == sock->destroy_task);
1065 = GNUNET_SCHEDULER_add_now (sock->sched,
1066 &destroy_continuation, sock);
1071 * Tell the receiver callback that a timeout was reached.
1074 signal_timeout (struct GNUNET_CONNECTION_Handle *sh)
1076 GNUNET_CONNECTION_Receiver receiver;
1078 #if DEBUG_CONNECTION
1079 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1080 "Network signals time out to receiver (%p)!\n", sh);
1082 GNUNET_assert (NULL != (receiver = sh->receiver));
1083 sh->receiver = NULL;
1084 receiver (sh->receiver_cls, NULL, 0, NULL, 0, 0);
1089 * Tell the receiver callback that we had an IO error.
1092 signal_error (struct GNUNET_CONNECTION_Handle *sh, int errcode)
1094 GNUNET_CONNECTION_Receiver receiver;
1095 GNUNET_assert (NULL != (receiver = sh->receiver));
1096 sh->receiver = NULL;
1097 receiver (sh->receiver_cls, NULL, 0, sh->addr, sh->addrlen, errcode);
1102 * This function is called once we either timeout
1103 * or have data ready to read.
1106 receive_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1108 struct GNUNET_CONNECTION_Handle *sh = cls;
1109 struct GNUNET_TIME_Absolute now;
1110 char buffer[sh->max];
1112 GNUNET_CONNECTION_Receiver receiver;
1114 sh->read_task = GNUNET_SCHEDULER_NO_TASK;
1115 if ( (GNUNET_YES == sh->ignore_shutdown) &&
1116 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
1118 /* ignore shutdown request, go again immediately */
1119 #if DEBUG_CONNECTION
1120 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1121 "Ignoring shutdown signal per configuration\n");
1123 sh->read_task = GNUNET_SCHEDULER_add_read_net (tc->sched,
1124 GNUNET_TIME_absolute_get_remaining
1125 (sh->receive_timeout),
1127 &receive_ready, sh);
1130 now = GNUNET_TIME_absolute_get ();
1131 if ((now.value > sh->receive_timeout.value) ||
1132 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_TIMEOUT)) ||
1133 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
1135 #if DEBUG_CONNECTION
1136 if (0 == (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1137 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1138 "Receive from `%s' encounters error: time out by %llums... (%p)\n",
1139 GNUNET_a2s (sh->addr, sh->addrlen),
1140 GNUNET_TIME_absolute_get_duration (sh->receive_timeout).
1143 signal_timeout (sh);
1146 if (sh->sock == NULL)
1148 /* connect failed for good */
1149 #if DEBUG_CONNECTION
1150 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1151 "Receive encounters error, socket closed... (%p)\n", sh);
1153 signal_error (sh, ECONNREFUSED);
1156 GNUNET_assert (GNUNET_NETWORK_fdset_isset (tc->read_ready, sh->sock));
1158 ret = GNUNET_NETWORK_socket_recv (sh->sock, buffer, sh->max);
1163 #if DEBUG_CONNECTION
1164 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1165 "Error receiving: %s\n", STRERROR (errno));
1167 signal_error (sh, errno);
1170 #if DEBUG_CONNECTION
1171 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1172 "receive_ready read %u/%u bytes from `%s' (%p)!\n",
1174 sh->max, GNUNET_a2s (sh->addr, sh->addrlen), sh);
1176 GNUNET_assert (NULL != (receiver = sh->receiver));
1177 sh->receiver = NULL;
1178 receiver (sh->receiver_cls, buffer, ret, sh->addr, sh->addrlen, 0);
1183 * This function is called after establishing a connection either has
1184 * succeeded or timed out. Note that it is possible that the attempt
1185 * timed out and that we're immediately retrying. If we are retrying,
1186 * we need to wait again (or timeout); if we succeeded, we need to
1187 * wait for data (or timeout).
1189 * @param cls our connection handle
1190 * @param tc task context describing why we are here
1193 receive_again (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1195 struct GNUNET_CONNECTION_Handle *sh = cls;
1196 struct GNUNET_TIME_Absolute now;
1198 sh->read_task = GNUNET_SCHEDULER_NO_TASK;
1199 if (sh->sock == NULL)
1201 /* not connected and no longer trying */
1202 #if DEBUG_CONNECTION
1203 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1204 "Receive encounters error, socket closed (%p)...\n", sh);
1206 signal_error (sh, ECONNREFUSED);
1209 now = GNUNET_TIME_absolute_get ();
1210 if ((now.value > sh->receive_timeout.value) ||
1211 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
1213 #if DEBUG_CONNECTION
1214 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1215 "Receive encounters error: time out (%p)...\n", sh);
1217 signal_timeout (sh);
1220 GNUNET_assert (sh->sock != NULL);
1221 /* connect succeeded, wait for data! */
1222 sh->read_task = GNUNET_SCHEDULER_add_read_net (tc->sched,
1223 GNUNET_TIME_absolute_get_remaining
1224 (sh->receive_timeout),
1226 &receive_ready, sh);
1231 * Receive data from the given socket. Note that this function will
1232 * call "receiver" asynchronously using the scheduler. It will
1233 * "immediately" return. Note that there MUST only be one active
1234 * receive call per socket at any given point in time (so do not
1235 * call receive again until the receiver callback has been invoked).
1237 * @param sock socket handle
1238 * @param max maximum number of bytes to read
1239 * @param timeout maximum amount of time to wait (use -1 for "forever")
1240 * @param receiver function to call with received data
1241 * @param receiver_cls closure for receiver
1244 GNUNET_CONNECTION_receive (struct GNUNET_CONNECTION_Handle *sock,
1246 struct GNUNET_TIME_Relative timeout,
1247 GNUNET_CONNECTION_Receiver receiver,
1250 struct GNUNET_SCHEDULER_TaskContext tc;
1252 GNUNET_assert ((sock->read_task == GNUNET_SCHEDULER_NO_TASK) &&
1253 (0 == (sock->ccs & COCO_RECEIVE_AGAIN)) &&
1254 (sock->receiver == NULL));
1255 sock->receiver = receiver;
1256 sock->receiver_cls = receiver_cls;
1257 sock->receive_timeout = GNUNET_TIME_relative_to_absolute (timeout);
1259 if (sock->sock != NULL)
1261 memset (&tc, 0, sizeof (tc));
1262 tc.sched = sock->sched;
1263 tc.reason = GNUNET_SCHEDULER_REASON_PREREQ_DONE;
1264 receive_again (sock, &tc);
1267 if ((sock->dns_active == NULL) && (sock->ap_head == NULL))
1269 receiver (receiver_cls, NULL, 0, NULL, 0, ETIMEDOUT);
1272 sock->ccs += COCO_RECEIVE_AGAIN;
1277 * Configure this connection to ignore shutdown signals.
1279 * @param sock socket handle
1280 * @param do_ignore GNUNET_YES to ignore, GNUNET_NO to restore default
1283 GNUNET_CONNECTION_ignore_shutdown (struct GNUNET_CONNECTION_Handle *sock,
1286 sock->ignore_shutdown = do_ignore;
1291 * Cancel receive job on the given socket. Note that the
1292 * receiver callback must not have been called yet in order
1293 * for the cancellation to be valid.
1295 * @param sock socket handle
1296 * @return closure of the original receiver callback closure
1299 GNUNET_CONNECTION_receive_cancel (struct GNUNET_CONNECTION_Handle *sock)
1301 if (sock->read_task != GNUNET_SCHEDULER_NO_TASK)
1303 GNUNET_assert (sock == GNUNET_SCHEDULER_cancel (sock->sched,
1305 sock->read_task = GNUNET_SCHEDULER_NO_TASK;
1309 GNUNET_assert (0 != (sock->ccs & COCO_RECEIVE_AGAIN));
1310 sock->ccs -= COCO_RECEIVE_AGAIN;
1312 sock->receiver = NULL;
1313 return sock->receiver_cls;
1318 * Try to call the transmit notify method (check if we do
1319 * have enough space available first)!
1321 * @param sock socket for which we should do this processing
1322 * @return GNUNET_YES if we were able to call notify
1325 process_notify (struct GNUNET_CONNECTION_Handle *sock)
1330 GNUNET_CONNECTION_TransmitReadyNotify notify;
1332 GNUNET_assert (sock->write_task == GNUNET_SCHEDULER_NO_TASK);
1333 if (NULL == (notify = sock->nth.notify_ready))
1335 used = sock->write_buffer_off - sock->write_buffer_pos;
1336 avail = sock->write_buffer_size - used;
1337 size = sock->nth.notify_size;
1338 if (sock->nth.notify_size > avail)
1340 sock->nth.notify_ready = NULL;
1341 if (sock->write_buffer_size - sock->write_buffer_off < size)
1343 /* need to compact */
1344 memmove (sock->write_buffer,
1345 &sock->write_buffer[sock->write_buffer_pos], used);
1346 sock->write_buffer_off -= sock->write_buffer_pos;
1347 sock->write_buffer_pos = 0;
1349 GNUNET_assert (sock->write_buffer_size - sock->write_buffer_off >= size);
1350 size = notify (sock->nth.notify_ready_cls,
1351 sock->write_buffer_size - sock->write_buffer_off,
1352 &sock->write_buffer[sock->write_buffer_off]);
1353 sock->write_buffer_off += size;
1359 * Task invoked by the scheduler when a call to transmit
1360 * is timing out (we never got enough buffer space to call
1361 * the callback function before the specified timeout
1364 * This task notifies the client about the timeout.
1367 transmit_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1369 struct GNUNET_CONNECTION_Handle *sock = cls;
1370 GNUNET_CONNECTION_TransmitReadyNotify notify;
1372 #if DEBUG_CONNECTION
1373 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1374 "transmit_timeout running (%p)\n", sock);
1376 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_TASK;
1377 #if DEBUG_CONNECTION
1378 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1379 "Transmit to `%s:%u/%s' fails, time out reached (%p).\n",
1381 sock->port, GNUNET_a2s (sock->addr, sock->addrlen), sock);
1383 GNUNET_assert (0 != (sock->ccs & COCO_TRANSMIT_READY));
1384 sock->ccs -= COCO_TRANSMIT_READY; /* remove request */
1385 notify = sock->nth.notify_ready;
1386 sock->nth.notify_ready = NULL;
1387 notify (sock->nth.notify_ready_cls, 0, NULL);
1392 * Task invoked by the scheduler when we failed to connect
1393 * at the time of being asked to transmit.
1395 * This task notifies the client about the error.
1398 connect_error (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1400 struct GNUNET_CONNECTION_Handle *sock = cls;
1401 GNUNET_CONNECTION_TransmitReadyNotify notify;
1403 #if DEBUG_CONNECTION
1404 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1405 "Transmission request of size %u fails, connection failed (%p).\n",
1406 sock->nth.notify_size, sock);
1408 sock->write_task = GNUNET_SCHEDULER_NO_TASK;
1409 notify = sock->nth.notify_ready;
1410 sock->nth.notify_ready = NULL;
1411 notify (sock->nth.notify_ready_cls, 0, NULL);
1416 transmit_error (struct GNUNET_CONNECTION_Handle *sock)
1418 GNUNET_CONNECTION_TransmitReadyNotify notify;
1420 if (NULL != sock->sock)
1422 GNUNET_NETWORK_socket_shutdown (sock->sock, SHUT_RDWR);
1423 GNUNET_break (GNUNET_OK ==
1424 GNUNET_NETWORK_socket_close (sock->sock));
1427 if (sock->read_task != GNUNET_SCHEDULER_NO_TASK)
1429 GNUNET_SCHEDULER_cancel (sock->sched,
1431 sock->read_task = GNUNET_SCHEDULER_NO_TASK;
1432 signal_timeout (sock);
1435 if (sock->nth.notify_ready == NULL)
1436 return; /* nobody to tell about it */
1437 notify = sock->nth.notify_ready;
1438 sock->nth.notify_ready = NULL;
1439 notify (sock->nth.notify_ready_cls, 0, NULL);
1444 * See if we are now connected. If not, wait longer for
1445 * connect to succeed. If connected, we should be able
1446 * to write now as well, unless we timed out.
1448 * @param cls our connection handle
1449 * @param tc task context describing why we are here
1452 transmit_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1454 struct GNUNET_CONNECTION_Handle *sock = cls;
1455 GNUNET_CONNECTION_TransmitReadyNotify notify;
1459 #if DEBUG_CONNECTION
1460 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1461 "transmit_ready running (%p).\n", sock);
1463 GNUNET_assert (sock->write_task != GNUNET_SCHEDULER_NO_TASK);
1464 sock->write_task = GNUNET_SCHEDULER_NO_TASK;
1465 GNUNET_assert (sock->nth.timeout_task == GNUNET_SCHEDULER_NO_TASK);
1466 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1468 if (sock->ignore_shutdown == GNUNET_YES)
1469 goto SCHEDULE_WRITE; /* ignore shutdown, go again immediately */
1470 #if DEBUG_CONNECTION
1471 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1472 "Transmit to `%s' fails, shutdown happened (%p).\n",
1473 GNUNET_a2s (sock->addr, sock->addrlen), sock);
1475 notify = sock->nth.notify_ready;
1476 sock->nth.notify_ready = NULL;
1477 notify (sock->nth.notify_ready_cls, 0, NULL);
1480 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_TIMEOUT))
1482 #if DEBUG_CONNECTION
1483 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1484 "Transmit to `%s' fails, time out reached (%p).\n",
1485 GNUNET_a2s (sock->addr, sock->addrlen), sock);
1487 notify = sock->nth.notify_ready;
1488 sock->nth.notify_ready = NULL;
1489 notify (sock->nth.notify_ready_cls, 0, NULL);
1492 GNUNET_assert (NULL != sock->sock);
1493 if (tc->write_ready == NULL)
1495 /* special circumstances (in particular,
1496 PREREQ_DONE after connect): not yet ready to write,
1497 but no "fatal" error either. Hence retry. */
1498 goto SCHEDULE_WRITE;
1500 if (!GNUNET_NETWORK_fdset_isset (tc->write_ready, sock->sock))
1502 #if DEBUG_CONNECTION
1503 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1505 ("Could not satisfy pending transmission request, socket closed or connect failed (%p).\n"),
1508 transmit_error (sock);
1509 return; /* connect failed for good, we're finished */
1511 GNUNET_assert (sock->write_buffer_off >= sock->write_buffer_pos);
1512 process_notify (sock);
1513 have = sock->write_buffer_off - sock->write_buffer_pos;
1516 /* no data ready for writing, terminate write loop */
1519 GNUNET_assert (have <= sock->write_buffer_size);
1520 GNUNET_assert (have + sock->write_buffer_pos <= sock->write_buffer_size);
1521 GNUNET_assert (sock->write_buffer_pos <= sock->write_buffer_size);
1523 ret = GNUNET_NETWORK_socket_send (sock->sock,
1524 &sock->write_buffer[sock->
1533 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1534 _("Failed to send to `%s': %s\n"),
1535 GNUNET_a2s (sock->addr,
1539 #if DEBUG_CONNECTION
1540 GNUNET_log_strerror (GNUNET_ERROR_TYPE_DEBUG, "send");
1542 transmit_error (sock);
1545 #if DEBUG_CONNECTION
1546 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1547 "transmit_ready transmitted %u/%u bytes to `%s' (%p)\n",
1549 have, GNUNET_a2s (sock->addr, sock->addrlen), sock);
1551 sock->write_buffer_pos += ret;
1552 if (sock->write_buffer_pos == sock->write_buffer_off)
1554 /* transmitted all pending data */
1555 sock->write_buffer_pos = 0;
1556 sock->write_buffer_off = 0;
1558 if ((sock->write_buffer_off == 0) && (NULL == sock->nth.notify_ready))
1559 return; /* all data sent! */
1560 /* not done writing, schedule more */
1562 #if DEBUG_CONNECTION
1563 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1564 "Re-scheduling transmit_ready (more to do) (%p).\n", sock);
1566 if (sock->write_task == GNUNET_SCHEDULER_NO_TASK)
1568 GNUNET_SCHEDULER_add_write_net (tc->sched,
1569 GNUNET_TIME_absolute_get_remaining
1570 (sock->nth.transmit_timeout),
1571 sock->sock, &transmit_ready, sock);
1576 * Ask the socket to call us once the specified number of bytes
1577 * are free in the transmission buffer. May call the notify
1578 * method immediately if enough space is available.
1580 * @param sock socket
1581 * @param size number of bytes to send
1582 * @param timeout after how long should we give up (and call
1583 * notify with buf NULL and size 0)?
1584 * @param notify function to call
1585 * @param notify_cls closure for notify
1586 * @return non-NULL if the notify callback was queued,
1587 * NULL if we are already going to notify someone else (busy)
1589 struct GNUNET_CONNECTION_TransmitHandle *
1590 GNUNET_CONNECTION_notify_transmit_ready (struct GNUNET_CONNECTION_Handle
1592 struct GNUNET_TIME_Relative timeout,
1593 GNUNET_CONNECTION_TransmitReadyNotify
1594 notify, void *notify_cls)
1596 if (sock->nth.notify_ready != NULL)
1598 GNUNET_assert (notify != NULL);
1599 GNUNET_assert (sock->write_buffer_size >= size);
1600 GNUNET_assert (sock->write_buffer_off <= sock->write_buffer_size);
1601 GNUNET_assert (sock->write_buffer_pos <= sock->write_buffer_size);
1602 GNUNET_assert (sock->write_buffer_pos <= sock->write_buffer_off);
1603 sock->nth.notify_ready = notify;
1604 sock->nth.notify_ready_cls = notify_cls;
1605 sock->nth.sh = sock;
1606 sock->nth.notify_size = size;
1607 sock->nth.transmit_timeout = GNUNET_TIME_relative_to_absolute (timeout);
1608 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == sock->nth.timeout_task);
1609 if ((sock->sock == NULL) &&
1610 (sock->ap_head == NULL) && (sock->dns_active == NULL))
1612 sock->write_task = GNUNET_SCHEDULER_add_now (sock->sched,
1613 &connect_error, sock);
1616 if (GNUNET_SCHEDULER_NO_TASK != sock->write_task)
1618 if (sock->sock != NULL)
1620 #if DEBUG_CONNECTION
1621 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1622 "Scheduling transmit_ready (%p).\n", sock);
1624 sock->write_task = GNUNET_SCHEDULER_add_write_net (sock->sched,
1625 GNUNET_TIME_absolute_get_remaining
1634 #if DEBUG_CONNECTION
1635 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1636 "CCS-Scheduling transmit_ready, adding timeout task (%p).\n",
1639 sock->ccs |= COCO_TRANSMIT_READY;
1640 sock->nth.timeout_task = GNUNET_SCHEDULER_add_delayed (sock->sched,
1650 * Cancel the specified transmission-ready
1654 GNUNET_CONNECTION_notify_transmit_ready_cancel (struct
1655 GNUNET_CONNECTION_TransmitHandle
1658 GNUNET_assert (h->notify_ready != NULL);
1659 if (0 != (h->sh->ccs & COCO_TRANSMIT_READY))
1661 #if DEBUG_CONNECTION
1662 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1663 "notify_transmit_ready_cancel cancels timeout_task (%p)\n",
1666 GNUNET_SCHEDULER_cancel (h->sh->sched, h->timeout_task);
1667 h->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1668 h->sh->ccs -= COCO_TRANSMIT_READY;
1672 if (h->sh->write_task != GNUNET_SCHEDULER_NO_TASK)
1674 GNUNET_SCHEDULER_cancel (h->sh->sched, h->sh->write_task);
1675 h->sh->write_task = GNUNET_SCHEDULER_NO_TASK;
1678 h->notify_ready = NULL;
1681 /* end of connection.c */