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/network/network.c
23 * @brief basic, low-level TCP networking interface
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.
34 * - can we merge receive_ready and receive_again?
35 * - can we integrate the nth.timeout_task with the write_task's timeout?
39 #include "gnunet_common.h"
40 #include "gnunet_network_lib.h"
41 #include "gnunet_scheduler_lib.h"
43 #define DEBUG_NETWORK GNUNET_NO
45 struct GNUNET_NETWORK_TransmitHandle
49 * Function to call if the send buffer has notify_size
52 GNUNET_NETWORK_TransmitReadyNotify notify_ready;
55 * Closure for notify_ready.
57 void *notify_ready_cls;
62 struct GNUNET_NETWORK_SocketHandle *sh;
65 * Timeout for receiving (in absolute time).
67 struct GNUNET_TIME_Absolute transmit_timeout;
70 * Task called on timeout.
72 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
75 * At what number of bytes available in the
76 * write buffer should the notify method be called?
83 * @brief handle for a network socket
85 struct GNUNET_NETWORK_SocketHandle
89 * Scheduler that was used for the connect task.
91 struct GNUNET_SCHEDULER_Handle *sched;
94 * Address information for connect (may be NULL).
99 * Index for the next struct addrinfo for connect attempts (may be NULL)
101 struct addrinfo *ai_pos;
104 * Network address of the other end-point, may be NULL.
106 struct sockaddr *addr;
109 * Pointer to our write buffer.
114 * Size of our write buffer.
116 size_t write_buffer_size;
119 * Current write-offset in write buffer (where
120 * would we write next).
122 size_t write_buffer_off;
125 * Current read-offset in write buffer (how many
126 * bytes have already been send).
128 size_t write_buffer_pos;
136 * Connect task that we may need to wait for.
138 GNUNET_SCHEDULER_TaskIdentifier connect_task;
141 * Read task that we may need to wait for.
143 GNUNET_SCHEDULER_TaskIdentifier read_task;
146 * Write task that we may need to wait for.
148 GNUNET_SCHEDULER_TaskIdentifier write_task;
151 * The handle we return for GNUNET_NETWORK_notify_transmit_ready.
153 struct GNUNET_NETWORK_TransmitHandle nth;
156 * Underlying OS's socket, set to -1 after fatal errors.
161 * Port to connect to.
166 * Function to call on data received, NULL
167 * if no receive is pending.
169 GNUNET_NETWORK_Receiver receiver;
172 * Closure for receiver.
177 * Timeout for receiving (in absolute time).
179 struct GNUNET_TIME_Absolute receive_timeout;
182 * Maximum number of bytes to read
191 * Create a socket handle by boxing an existing OS socket. The OS
192 * socket should henceforth be no longer used directly.
193 * GNUNET_socket_destroy will close it.
195 * @param sched scheduler to use
196 * @param osSocket existing socket to box
197 * @param maxbuf maximum write buffer size for the socket (use
198 * 0 for sockets that need no write buffers, such as listen sockets)
199 * @return the boxed socket handle
201 struct GNUNET_NETWORK_SocketHandle *
202 GNUNET_NETWORK_socket_create_from_existing (struct GNUNET_SCHEDULER_Handle
203 *sched, int osSocket,
206 struct GNUNET_NETWORK_SocketHandle *ret;
207 ret = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_SocketHandle) + maxbuf);
208 ret->write_buffer = (char *) &ret[1];
209 ret->write_buffer_size = maxbuf;
210 ret->sock = osSocket;
217 * Create a socket handle by accepting on a listen socket. This
218 * function may block if the listen socket has no connection ready.
220 * @param sched scheduler to use
221 * @param access function to use to check if access is allowed
222 * @param access_cls closure for access
223 * @param lsock listen socket
224 * @param maxbuf maximum write buffer size for the socket (use
225 * 0 for sockets that need no write buffers, such as listen sockets)
226 * @return the socket handle, NULL on error
228 struct GNUNET_NETWORK_SocketHandle *
229 GNUNET_NETWORK_socket_create_from_accept (struct GNUNET_SCHEDULER_Handle
231 GNUNET_NETWORK_AccessCheck access,
232 void *access_cls, int lsock,
235 struct GNUNET_NETWORK_SocketHandle *ret;
240 struct sockaddr_in *v4;
241 struct sockaddr_in6 *v6;
245 addrlen = sizeof (addr);
246 fd = accept (lsock, (struct sockaddr *) &addr, &addrlen);
249 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "accept");
254 if (0 != fcntl (fd, F_SETFD, fcntl (fd, F_GETFD) | FD_CLOEXEC))
255 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
258 if (addrlen > sizeof (addr))
261 GNUNET_break (0 == CLOSE (fd));
265 sa = (struct sockaddr *) addr;
266 v6 = (struct sockaddr_in6 *) addr;
267 if ((sa->sa_family == AF_INET6) && (IN6_IS_ADDR_V4MAPPED (&v6->sin6_addr)))
269 /* convert to V4 address */
270 v4 = GNUNET_malloc (sizeof (struct sockaddr_in));
271 memset (v4, 0, sizeof (struct sockaddr_in));
272 v4->sin_family = AF_INET;
273 memcpy (&v4->sin_addr,
274 &((char *) &v6->sin6_addr)[sizeof (struct in6_addr) -
275 sizeof (struct in_addr)],
276 sizeof (struct in_addr));
277 v4->sin_port = v6->sin6_port;
279 addrlen = sizeof (struct sockaddr_in);
283 uaddr = GNUNET_malloc (addrlen);
284 memcpy (uaddr, addr, addrlen);
287 if ((access != NULL) &&
288 (GNUNET_YES != (aret = access (access_cls, uaddr, addrlen))))
290 if (aret == GNUNET_NO)
291 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
292 _("Access denied to `%s'\n"),
293 GNUNET_a2s(uaddr, addrlen));
294 GNUNET_break (0 == SHUTDOWN (fd, SHUT_RDWR));
295 GNUNET_break (0 == CLOSE (fd));
300 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
301 _("Accepting connection from `%s'\n"),
302 GNUNET_a2s(uaddr, addrlen));
304 ret = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_SocketHandle) + maxbuf);
305 ret->write_buffer = (char *) &ret[1];
306 ret->write_buffer_size = maxbuf;
308 ret->addrlen = addrlen;
315 * Obtain the network address of the other party.
317 * @param sock the client to get the address for
318 * @param addr where to store the address
319 * @param addrlen where to store the length of the address
320 * @return GNUNET_OK on success
323 GNUNET_NETWORK_socket_get_address (struct GNUNET_NETWORK_SocketHandle *sock,
324 void **addr, size_t * addrlen)
326 if ((sock->addr == NULL) || (sock->addrlen == 0))
328 *addr = GNUNET_malloc (sock->addrlen);
329 memcpy (*addr, sock->addr, sock->addrlen);
330 *addrlen = sock->addrlen;
336 * Set if a socket should use blocking or non-blocking IO.
338 * @return GNUNET_OK on success, GNUNET_SYSERR on error
341 socket_set_blocking (int handle, int doBlock)
347 if (ioctlsocket (plibc_fd_get_handle (handle), FIONBIO, &mode) ==
350 SetErrnoFromWinsockError (WSAGetLastError ());
351 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctlsocket");
352 return GNUNET_SYSERR;
355 if (ioctlsocket (handle, FIONBIO, &mode) == SOCKET_ERROR)
357 SetErrnoFromWinsockError (WSAGetLastError ());
358 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctlsocket");
359 return GNUNET_SYSERR;
362 /* store the blocking mode */
364 plibc_fd_set_blocking (handle, doBlock);
366 __win_SetHandleBlockingMode (handle, doBlock);
372 int flags = fcntl (handle, F_GETFL);
375 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "fcntl");
376 return GNUNET_SYSERR;
379 flags &= ~O_NONBLOCK;
382 if (0 != fcntl (handle, F_SETFL, flags))
384 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "fcntl");
385 return GNUNET_SYSERR;
393 * Initiate asynchronous TCP connect request.
395 * @param sock what socket to connect
396 * @return GNUNET_SYSERR error (no more addresses to try)
399 try_connect (struct GNUNET_NETWORK_SocketHandle *sock)
403 if (sock->addr != NULL)
405 GNUNET_free (sock->addr);
411 if (sock->ai_pos == NULL)
413 /* no more addresses to try, fatal! */
414 return GNUNET_SYSERR;
416 switch (sock->ai_pos->ai_family)
419 ((struct sockaddr_in *) sock->ai_pos->ai_addr)->sin_port =
423 ((struct sockaddr_in6 *) sock->ai_pos->ai_addr)->sin6_port =
427 sock->ai_pos = sock->ai_pos->ai_next;
430 s = SOCKET (sock->ai_pos->ai_family, SOCK_STREAM, 0);
433 /* maybe unsupported address family, try next */
434 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "socket");
435 sock->ai_pos = sock->ai_pos->ai_next;
440 if (0 != fcntl (s, F_SETFD, fcntl (s, F_GETFD) | FD_CLOEXEC))
441 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
444 if (GNUNET_SYSERR == socket_set_blocking (s, GNUNET_NO))
446 /* we'll treat this one as fatal */
447 GNUNET_break (0 == CLOSE (s));
448 return GNUNET_SYSERR;
451 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
452 _("Trying to connect to `%s'\n"),
453 GNUNET_a2s(sock->ai_pos->ai_addr,
454 sock->ai_pos->ai_addrlen));
456 if ((0 != CONNECT (s,
457 sock->ai_pos->ai_addr,
458 sock->ai_pos->ai_addrlen)) && (errno != EINPROGRESS))
460 /* maybe refused / unsupported address, try next */
461 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "connect");
462 GNUNET_break (0 == CLOSE (s));
467 /* got one! copy address information! */
468 sock->addrlen = sock->ai_pos->ai_addrlen;
469 sock->addr = GNUNET_malloc (sock->addrlen);
470 memcpy (sock->addr, sock->ai_pos->ai_addr, sock->addrlen);
471 sock->ai_pos = sock->ai_pos->ai_next;
478 * Scheduler let us know that we're either ready to
479 * write on the socket OR connect timed out. Do the
483 connect_continuation (void *cls,
484 const struct GNUNET_SCHEDULER_TaskContext *tc)
486 struct GNUNET_NETWORK_SocketHandle *sock = cls;
490 /* nobody needs to wait for us anymore... */
491 sock->connect_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
492 /* Note: write-ready does NOT mean connect succeeded,
493 we need to use getsockopt to be sure */
494 len = sizeof (error);
497 if ((0 == (tc->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) ||
498 (0 != getsockopt (sock->sock, SOL_SOCKET, SO_ERROR, &error, &len)) ||
499 (error != 0) || (errno != 0))
502 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
503 "Failed to establish TCP connection to `%s'\n",
504 GNUNET_a2s(sock->addr, sock->addrlen));
506 /* connect failed / timed out */
507 GNUNET_break (0 == CLOSE (sock->sock));
509 if (GNUNET_SYSERR == try_connect (sock))
511 /* failed for good */
513 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
514 "Failed to establish TCP connection, no further addresses to try.\n");
516 /* connect failed / timed out */
517 GNUNET_break (sock->ai_pos == NULL);
518 freeaddrinfo (sock->ai);
522 sock->connect_task = GNUNET_SCHEDULER_add_write (tc->sched, GNUNET_NO, /* abort on shutdown */
523 GNUNET_SCHEDULER_PRIORITY_KEEP,
524 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
525 GNUNET_NETWORK_CONNECT_RETRY_TIMEOUT,
527 &connect_continuation,
531 /* connect succeeded! clean up "ai" */
533 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
534 "Connection to `%s' succeeded!\n",
535 GNUNET_a2s(sock->addr, sock->addrlen));
537 freeaddrinfo (sock->ai);
544 * Create a socket handle by (asynchronously) connecting to a host.
545 * This function returns immediately, even if the connection has not
546 * yet been established. This function only creates TCP connections.
548 * @param sched scheduler to use
549 * @param hostname name of the host to connect to
550 * @param port port to connect to
551 * @param maxbuf maximum write buffer size for the socket (use
552 * 0 for sockets that need no write buffers, such as listen sockets)
553 * @return the socket handle
555 struct GNUNET_NETWORK_SocketHandle *
556 GNUNET_NETWORK_socket_create_from_connect (struct GNUNET_SCHEDULER_Handle
557 *sched, const char *hostname,
558 uint16_t port, size_t maxbuf)
560 struct GNUNET_NETWORK_SocketHandle *ret;
561 struct addrinfo hints;
564 ret = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_SocketHandle) + maxbuf);
567 ret->write_buffer = (char *) &ret[1];
568 ret->write_buffer_size = maxbuf;
570 memset (&hints, 0, sizeof (hints));
571 hints.ai_family = AF_UNSPEC;
572 hints.ai_socktype = SOCK_STREAM;
573 if (0 != (ec = getaddrinfo (hostname, NULL, &hints, &ret->ai)))
575 GNUNET_log (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
576 "`%s' failed for hostname `%s': %s\n",
577 "getaddrinfo", hostname, gai_strerror (ec));
581 ret->ai_pos = ret->ai;
582 if (GNUNET_SYSERR == try_connect (ret))
584 freeaddrinfo (ret->ai);
588 ret->connect_task = GNUNET_SCHEDULER_add_write (sched, GNUNET_NO, /* abort on shutdown */
589 GNUNET_SCHEDULER_PRIORITY_KEEP,
590 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
591 GNUNET_NETWORK_CONNECT_RETRY_TIMEOUT,
593 &connect_continuation, ret);
600 * Create a socket handle by (asynchronously) connecting to a host.
601 * This function returns immediately, even if the connection has not
602 * yet been established. This function only creates TCP connections.
604 * @param sched scheduler to use
605 * @param af_family address family to use
606 * @param serv_addr server address
607 * @param addrlen length of server address
608 * @param maxbuf maximum write buffer size for the socket (use
609 * 0 for sockets that need no write buffers, such as listen sockets)
610 * @return the socket handle
612 struct GNUNET_NETWORK_SocketHandle *
613 GNUNET_NETWORK_socket_create_from_sockaddr (struct GNUNET_SCHEDULER_Handle
614 *sched, int af_family,
615 const struct sockaddr *serv_addr,
616 socklen_t addrlen, size_t maxbuf)
619 struct GNUNET_NETWORK_SocketHandle *ret;
621 s = SOCKET (af_family, SOCK_STREAM, 0);
624 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING |
625 GNUNET_ERROR_TYPE_BULK, "socket");
629 if (0 != fcntl (s, F_SETFD, fcntl (s, F_GETFD) | FD_CLOEXEC))
630 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
633 if (GNUNET_SYSERR == socket_set_blocking (s, GNUNET_NO))
635 /* we'll treat this one as fatal */
636 GNUNET_break (0 == CLOSE (s));
640 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
641 _("Trying to connect to `%s'\n"),
642 GNUNET_a2s(serv_addr, addrlen));
644 if ((0 != CONNECT (s, serv_addr, addrlen)) && (errno != EINPROGRESS))
646 /* maybe refused / unsupported address, try next */
647 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "connect");
648 GNUNET_break (0 == CLOSE (s));
651 ret = GNUNET_NETWORK_socket_create_from_existing (sched, s, maxbuf);
652 ret->addr = GNUNET_malloc (addrlen);
653 memcpy (ret->addr, serv_addr, addrlen);
654 ret->addrlen = addrlen;
660 * Check if socket is valid (no fatal errors have happened so far).
661 * Note that a socket that is still trying to connect is considered
664 * @param sock socket to check
665 * @return GNUNET_YES if valid, GNUNET_NO otherwise
668 GNUNET_NETWORK_socket_check (struct GNUNET_NETWORK_SocketHandle *sock)
670 if (sock->ai != NULL)
671 return GNUNET_YES; /* still trying to connect */
672 return (sock->sock == -1) ? GNUNET_NO : GNUNET_YES;
677 * Scheduler let us know that the connect task is finished (or was
678 * cancelled due to shutdown). Now really clean up.
681 destroy_continuation (void *cls,
682 const struct GNUNET_SCHEDULER_TaskContext *tc)
684 struct GNUNET_NETWORK_SocketHandle *sock = cls;
685 GNUNET_NETWORK_TransmitReadyNotify notify;
687 if (sock->write_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
689 GNUNET_SCHEDULER_add_after (sock->sched,
691 GNUNET_SCHEDULER_PRIORITY_KEEP,
693 &destroy_continuation, sock);
696 if (sock->sock != -1)
699 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Shutting down socket.\n");
701 SHUTDOWN (sock->sock, SHUT_RDWR);
703 if (sock->read_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
705 GNUNET_SCHEDULER_add_after (sock->sched,
707 GNUNET_SCHEDULER_PRIORITY_KEEP,
709 &destroy_continuation, sock);
712 if (NULL != (notify = sock->nth.notify_ready))
714 sock->nth.notify_ready = NULL;
715 notify (sock->nth.notify_ready_cls, 0, NULL);
716 if (sock->nth.timeout_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
718 GNUNET_SCHEDULER_cancel (sock->sched, sock->nth.timeout_task);
719 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
722 if (sock->sock != -1)
723 GNUNET_break (0 == CLOSE (sock->sock));
724 GNUNET_free_non_null (sock->addr);
725 if (sock->ai != NULL)
726 freeaddrinfo (sock->ai);
732 * Close the socket and free associated resources. Pending
733 * transmissions are simply dropped. A pending receive call will be
734 * called with an error code of "EPIPE".
736 * @param sock socket to destroy
739 GNUNET_NETWORK_socket_destroy (struct GNUNET_NETWORK_SocketHandle *sock)
741 if (sock->write_buffer_off == 0)
742 sock->ai_pos = NULL; /* if we're still trying to connect and have
743 no message pending, stop trying! */
744 GNUNET_assert (sock->sched != NULL);
745 GNUNET_SCHEDULER_add_after (sock->sched,
747 GNUNET_SCHEDULER_PRIORITY_KEEP,
749 &destroy_continuation, sock);
753 * Tell the receiver callback that a timeout was reached.
756 signal_timeout (struct GNUNET_NETWORK_SocketHandle *sh)
758 GNUNET_NETWORK_Receiver receiver;
761 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
762 "Network signals time out to receiver!\n");
764 GNUNET_assert (NULL != (receiver = sh->receiver));
766 receiver (sh->receiver_cls, NULL, 0, NULL, 0, 0);
771 * Tell the receiver callback that we had an IO error.
774 signal_error (struct GNUNET_NETWORK_SocketHandle *sh, int errcode)
776 GNUNET_NETWORK_Receiver receiver;
777 GNUNET_assert (NULL != (receiver = sh->receiver));
779 receiver (sh->receiver_cls, NULL, 0, sh->addr, sh->addrlen, errcode);
784 * This function is called once we either timeout
785 * or have data ready to read.
788 receive_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
790 struct GNUNET_NETWORK_SocketHandle *sh = cls;
791 struct GNUNET_TIME_Absolute now;
792 char buffer[sh->max];
794 GNUNET_NETWORK_Receiver receiver;
796 sh->read_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
797 now = GNUNET_TIME_absolute_get ();
798 if ((now.value > sh->receive_timeout.value) ||
799 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_TIMEOUT)) ||
800 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
803 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
804 "Receive encounters error: time out...\n");
811 /* connect failed for good */
813 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
814 "Receive encounters error, socket closed...\n");
816 signal_error (sh, ECONNREFUSED);
819 GNUNET_assert (FD_ISSET (sh->sock, tc->read_ready));
821 ret = RECV (sh->sock, buffer, sh->max,
834 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
835 "Error receiving: %s\n", STRERROR (errno));
837 signal_error (sh, errno);
841 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
842 "receive_ready read %u/%u bytes from `%s'!\n",
845 GNUNET_a2s(sh->addr, sh->addrlen));
847 GNUNET_assert (NULL != (receiver = sh->receiver));
849 receiver (sh->receiver_cls, buffer, ret, sh->addr, sh->addrlen, 0);
854 * This function is called after establishing a connection either has
855 * succeeded or timed out. Note that it is possible that the attempt
856 * timed out and that we're immediately retrying. If we are retrying,
857 * we need to wait again (or timeout); if we succeeded, we need to
858 * wait for data (or timeout).
861 receive_again (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
863 struct GNUNET_NETWORK_SocketHandle *sh = cls;
864 struct GNUNET_TIME_Absolute now;
866 sh->read_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
867 if ((sh->sock == -1) &&
868 (sh->connect_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK))
870 /* not connected and no longer trying */
872 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
873 "Receive encounters error, socket closed...\n");
875 signal_error (sh, ECONNREFUSED);
878 now = GNUNET_TIME_absolute_get ();
879 if ((now.value > sh->receive_timeout.value) ||
880 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
883 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
884 "Receive encounters error: time out...\n");
889 if (sh->connect_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
891 /* connect was retried */
892 sh->read_task = GNUNET_SCHEDULER_add_after (tc->sched,
894 GNUNET_SCHEDULER_PRIORITY_KEEP,
899 /* connect succeeded, wait for data! */
900 sh->read_task = GNUNET_SCHEDULER_add_read (tc->sched,
902 GNUNET_SCHEDULER_PRIORITY_KEEP,
904 GNUNET_TIME_absolute_get_remaining
905 (sh->receive_timeout),
906 sh->sock, &receive_ready,
912 * Receive data from the given socket. Note that this function will
913 * call "receiver" asynchronously using the scheduler. It will
914 * "immediately" return. Note that there MUST only be one active
915 * receive call per socket at any given point in time (so do not
916 * call receive again until the receiver callback has been invoked).
918 * @param sched scheduler to use
919 * @param sock socket handle
920 * @param max maximum number of bytes to read
921 * @param timeout maximum amount of time to wait (use -1 for "forever")
922 * @param receiver function to call with received data
923 * @param receiver_cls closure for receiver
924 * @return scheduler task ID used for receiving, GNUNET_SCHEDULER_NO_PREREQUISITE_TASK on error
926 GNUNET_SCHEDULER_TaskIdentifier
927 GNUNET_NETWORK_receive (struct GNUNET_NETWORK_SocketHandle *sock,
929 struct GNUNET_TIME_Relative timeout,
930 GNUNET_NETWORK_Receiver receiver, void *receiver_cls)
932 struct GNUNET_SCHEDULER_TaskContext tc;
934 GNUNET_assert ((sock->read_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK) &&
935 (sock->receiver == NULL));
936 sock->receiver = receiver;
937 sock->receiver_cls = receiver_cls;
938 sock->receive_timeout = GNUNET_TIME_relative_to_absolute (timeout);
940 memset (&tc, 0, sizeof (tc));
941 tc.sched = sock->sched;
942 tc.reason = GNUNET_SCHEDULER_REASON_PREREQ_DONE;
943 receive_again (sock, &tc);
944 return sock->read_task;
949 * Cancel receive job on the given socket. Note that the
950 * receiver callback must not have been called yet in order
951 * for the cancellation to be valid.
953 * @param sock socket handle
954 * @param task task identifier returned from the receive call
955 * @return closure of the original receiver callback
958 GNUNET_NETWORK_receive_cancel (struct GNUNET_NETWORK_SocketHandle *sock,
959 GNUNET_SCHEDULER_TaskIdentifier task)
961 GNUNET_assert (sock->read_task == task);
962 GNUNET_assert (sock == GNUNET_SCHEDULER_cancel (sock->sched, task));
963 sock->read_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
964 sock->receiver = NULL;
965 return sock->receiver_cls;
970 * Try to call the transmit notify method (check if we do
971 * have enough space available first)!
973 * @param sock socket for which we should do this processing
974 * @return GNUNET_YES if we were able to call notify
977 process_notify (struct GNUNET_NETWORK_SocketHandle *sock)
982 GNUNET_NETWORK_TransmitReadyNotify notify;
984 GNUNET_assert (sock->write_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK);
985 if (NULL == (notify = sock->nth.notify_ready))
987 used = sock->write_buffer_off - sock->write_buffer_pos;
988 avail = sock->write_buffer_size - used;
989 size = sock->nth.notify_size;
990 if (sock->nth.notify_size > avail)
992 sock->nth.notify_ready = NULL;
993 if (sock->nth.timeout_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
995 GNUNET_SCHEDULER_cancel (sock->sched, sock->nth.timeout_task);
996 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
998 if (sock->write_buffer_size - sock->write_buffer_off < size)
1000 /* need to compact */
1001 memmove (sock->write_buffer,
1002 &sock->write_buffer[sock->write_buffer_pos], used);
1003 sock->write_buffer_off -= sock->write_buffer_pos;
1004 sock->write_buffer_pos = 0;
1006 GNUNET_assert (sock->write_buffer_size - sock->write_buffer_off >= size);
1007 size = notify (sock->nth.notify_ready_cls,
1008 sock->write_buffer_size - sock->write_buffer_off,
1009 &sock->write_buffer[sock->write_buffer_off]);
1010 sock->write_buffer_off += size;
1016 * Task invoked by the scheduler when a call to transmit
1017 * is timing out (we never got enough buffer space to call
1018 * the callback function before the specified timeout
1021 * This task notifies the client about the timeout.
1024 transmit_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1026 struct GNUNET_NETWORK_SocketHandle *sock = cls;
1027 GNUNET_NETWORK_TransmitReadyNotify notify;
1030 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmit fails, time out reached.\n");
1032 notify = sock->nth.notify_ready;
1033 sock->nth.notify_ready = NULL;
1034 notify (sock->nth.notify_ready_cls, 0, NULL);
1039 transmit_error (struct GNUNET_NETWORK_SocketHandle *sock)
1041 if (sock->nth.notify_ready == NULL)
1042 return; /* nobody to tell about it */
1043 if (sock->nth.timeout_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1045 GNUNET_SCHEDULER_cancel (sock->sched, sock->nth.timeout_task);
1046 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1048 transmit_timeout (sock, NULL);
1053 * See if we are now connected. If not, wait longer for
1054 * connect to succeed. If connected, we should be able
1055 * to write now as well, unless we timed out.
1058 transmit_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1060 struct GNUNET_NETWORK_SocketHandle *sock = cls;
1064 GNUNET_assert (sock->write_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK);
1065 sock->write_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1066 if (sock->connect_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1068 /* still waiting for connect */
1069 GNUNET_assert (sock->write_task ==
1070 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK);
1072 GNUNET_SCHEDULER_add_delayed (tc->sched, GNUNET_NO,
1073 GNUNET_SCHEDULER_PRIORITY_KEEP,
1075 GNUNET_TIME_UNIT_ZERO, &transmit_ready,
1079 if (sock->sock == -1)
1082 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1083 _("Could not satisfy pending transmission request, socket closed or connect failed.\n"));
1085 transmit_error (sock);
1086 return; /* connect failed for good, we're finished */
1088 if ((tc->write_ready == NULL) || (!FD_ISSET (sock->sock, tc->write_ready)))
1090 /* special circumstances: not yet ready to write */
1091 goto SCHEDULE_WRITE;
1093 GNUNET_assert (sock->write_buffer_off >= sock->write_buffer_pos);
1094 process_notify (sock);
1095 have = sock->write_buffer_off - sock->write_buffer_pos;
1098 /* no data ready for writing, terminate write loop */
1102 ret = SEND (sock->sock,
1103 &sock->write_buffer[sock->write_buffer_pos],
1107 MSG_DONTWAIT | MSG_NOSIGNAL
1117 GNUNET_log_strerror (GNUNET_ERROR_TYPE_DEBUG, "send");
1119 SHUTDOWN (sock->sock, SHUT_RDWR);
1120 GNUNET_break (0 == CLOSE (sock->sock));
1122 transmit_error (sock);
1126 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1127 "transmit_ready transmitted %u/%u bytes to `%s'\n",
1130 GNUNET_a2s(sock->addr, sock->addrlen));
1132 sock->write_buffer_pos += ret;
1133 if (sock->write_buffer_pos == sock->write_buffer_off)
1135 /* transmitted all pending data */
1136 sock->write_buffer_pos = 0;
1137 sock->write_buffer_off = 0;
1139 if ((sock->write_buffer_off == 0) && (NULL == sock->nth.notify_ready))
1140 return; /* all data sent! */
1141 /* not done writing, schedule more */
1143 if (sock->write_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1145 GNUNET_SCHEDULER_add_write (tc->sched,
1147 GNUNET_SCHEDULER_PRIORITY_KEEP,
1148 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1149 GNUNET_TIME_UNIT_FOREVER_REL,
1150 sock->sock, &transmit_ready, sock);
1155 * Ask the socket to call us once the specified number of bytes
1156 * are free in the transmission buffer. May call the notify
1157 * method immediately if enough space is available.
1159 * @param sock socket
1160 * @param size number of bytes to send
1161 * @param timeout after how long should we give up (and call
1162 * notify with buf NULL and size 0)?
1163 * @param notify function to call
1164 * @param notify_cls closure for notify
1165 * @return non-NULL if the notify callback was queued,
1166 * NULL if we are already going to notify someone else (busy)
1168 struct GNUNET_NETWORK_TransmitHandle *
1169 GNUNET_NETWORK_notify_transmit_ready (struct GNUNET_NETWORK_SocketHandle
1171 struct GNUNET_TIME_Relative timeout,
1172 GNUNET_NETWORK_TransmitReadyNotify
1173 notify, void *notify_cls)
1175 if (sock->nth.notify_ready != NULL)
1177 GNUNET_assert (notify != NULL);
1178 GNUNET_assert (sock->write_buffer_size >= size);
1180 if ((sock->sock == -1) &&
1181 (sock->connect_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK))
1184 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1185 "Transmission request fails, connection failed.\n");
1187 notify (notify_cls, 0, NULL);
1190 GNUNET_assert (sock->write_buffer_off <= sock->write_buffer_size);
1191 GNUNET_assert (sock->write_buffer_pos <= sock->write_buffer_size);
1192 GNUNET_assert (sock->write_buffer_pos <= sock->write_buffer_off);
1193 sock->nth.notify_ready = notify;
1194 sock->nth.notify_ready_cls = notify_cls;
1195 sock->nth.sh = sock;
1196 sock->nth.notify_size = size;
1197 sock->nth.transmit_timeout = GNUNET_TIME_relative_to_absolute (timeout);
1198 sock->nth.timeout_task = GNUNET_SCHEDULER_add_delayed (sock->sched,
1200 GNUNET_SCHEDULER_PRIORITY_KEEP,
1201 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1205 if (sock->write_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1206 sock->write_task = GNUNET_SCHEDULER_add_delayed (sock->sched,
1208 GNUNET_SCHEDULER_PRIORITY_KEEP,
1210 GNUNET_TIME_UNIT_ZERO,
1211 &transmit_ready, sock);
1217 * Cancel the specified transmission-ready
1221 GNUNET_NETWORK_notify_transmit_ready_cancel (struct
1222 GNUNET_NETWORK_TransmitHandle *h)
1224 GNUNET_assert (h->notify_ready != NULL);
1225 GNUNET_SCHEDULER_cancel (h->sh->sched, h->timeout_task);
1226 h->timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1227 h->notify_ready = NULL;
1231 #if 0 /* keep Emacsens' auto-indent happy */