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.
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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.
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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;
237 char msg[INET6_ADDRSTRLEN];
242 struct sockaddr_in *v4;
243 struct sockaddr_in6 *v6;
247 addrlen = sizeof (addr);
248 fd = accept (lsock, (struct sockaddr *) &addr, &addrlen);
251 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,
257 if (addrlen > sizeof (addr))
260 GNUNET_break (0 == CLOSE (fd));
264 sa = (struct sockaddr *) addr;
265 v6 = (struct sockaddr_in6 *) addr;
266 if ((sa->sa_family == AF_INET6) && (IN6_IS_ADDR_V4MAPPED (&v6->sin6_addr)))
268 /* convert to V4 address */
269 v4 = GNUNET_malloc (sizeof (struct sockaddr_in));
270 memset (v4, 0, sizeof (struct sockaddr_in));
271 v4->sin_family = AF_INET;
272 memcpy (&v4->sin_addr,
273 &((char *) &v6->sin6_addr)[sizeof (struct in6_addr) -
274 sizeof (struct in_addr)],
275 sizeof (struct in_addr));
276 v4->sin_port = v6->sin6_port;
278 addrlen = sizeof (struct sockaddr_in);
282 uaddr = GNUNET_malloc (addrlen);
283 memcpy (uaddr, addr, addrlen);
286 if ((access != NULL) &&
287 (GNUNET_YES != (aret = access (access_cls, uaddr, addrlen))))
289 if (aret == GNUNET_NO)
291 fam = ((struct sockaddr *) addr)->sa_family;
292 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
293 _("Access denied to `%s'\n"),
296 ? (const void *) &((struct sockaddr_in6 *)
297 &addr)->sin6_addr : (const
300 &((struct sockaddr_in *) &addr)->sin_addr,
303 GNUNET_break (0 == SHUTDOWN (fd, SHUT_RDWR));
304 GNUNET_break (0 == CLOSE (fd));
308 ret = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_SocketHandle) + maxbuf);
309 ret->write_buffer = (char *) &ret[1];
310 ret->write_buffer_size = maxbuf;
312 ret->addrlen = addrlen;
319 * Obtain the network address of the other party.
321 * @param sock the client to get the address for
322 * @param addr where to store the address
323 * @param addrlen where to store the length of the address
324 * @return GNUNET_OK on success
327 GNUNET_NETWORK_socket_get_address (struct GNUNET_NETWORK_SocketHandle *sock,
328 void **addr, size_t * addrlen)
330 if ((sock->addr == NULL) || (sock->addrlen == 0))
332 *addr = GNUNET_malloc (sock->addrlen);
333 memcpy (*addr, sock->addr, sock->addrlen);
334 *addrlen = sock->addrlen;
340 * Set if a socket should use blocking or non-blocking IO.
342 * @return GNUNET_OK on success, GNUNET_SYSERR on error
345 socket_set_blocking (int handle, int doBlock)
351 if (ioctlsocket (plibc_fd_get_handle (handle), FIONBIO, &mode) ==
354 SetErrnoFromWinsockError (WSAGetLastError ());
355 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctlsocket");
356 return GNUNET_SYSERR;
359 if (ioctlsocket (handle, FIONBIO, &mode) == SOCKET_ERROR)
361 SetErrnoFromWinsockError (WSAGetLastError ());
362 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "ioctlsocket");
363 return GNUNET_SYSERR;
366 /* store the blocking mode */
368 plibc_fd_set_blocking (handle, doBlock);
370 __win_SetHandleBlockingMode (handle, doBlock);
376 int flags = fcntl (handle, F_GETFL);
379 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "fcntl");
380 return GNUNET_SYSERR;
383 flags &= ~O_NONBLOCK;
386 if (0 != fcntl (handle, F_SETFL, flags))
388 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "fcntl");
389 return GNUNET_SYSERR;
397 * Initiate asynchronous TCP connect request.
399 * @param sock what socket to connect
400 * @return GNUNET_SYSERR error (no more addresses to try)
403 try_connect (struct GNUNET_NETWORK_SocketHandle *sock)
407 if (sock->addr != NULL)
409 GNUNET_free (sock->addr);
415 if (sock->ai_pos == NULL)
417 /* no more addresses to try, fatal! */
418 return GNUNET_SYSERR;
420 switch (sock->ai_pos->ai_family)
423 ((struct sockaddr_in *) sock->ai_pos->ai_addr)->sin_port =
427 ((struct sockaddr_in6 *) sock->ai_pos->ai_addr)->sin6_port =
431 sock->ai_pos = sock->ai_pos->ai_next;
434 s = SOCKET (sock->ai_pos->ai_family, SOCK_STREAM, 0);
437 /* maybe unsupported address family, try next */
438 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "socket");
439 sock->ai_pos = sock->ai_pos->ai_next;
442 if (0 != fcntl (s, F_SETFD, fcntl (s, F_GETFD) | FD_CLOEXEC))
443 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
445 if (GNUNET_SYSERR == socket_set_blocking (s, GNUNET_NO))
447 /* we'll treat this one as fatal */
448 GNUNET_break (0 == CLOSE (s));
449 return GNUNET_SYSERR;
451 if ((0 != CONNECT (s,
452 sock->ai_pos->ai_addr,
453 sock->ai_pos->ai_addrlen)) && (errno != EINPROGRESS))
455 /* maybe refused / unsupported address, try next */
456 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "connect");
457 GNUNET_break (0 == CLOSE (s));
462 /* got one! copy address information! */
463 sock->addrlen = sock->ai_pos->ai_addrlen;
464 sock->addr = GNUNET_malloc (sock->addrlen);
465 memcpy (sock->addr, sock->ai_pos->ai_addr, sock->addrlen);
466 sock->ai_pos = sock->ai_pos->ai_next;
473 * Scheduler let us know that we're either ready to
474 * write on the socket OR connect timed out. Do the
478 connect_continuation (void *cls,
479 const struct GNUNET_SCHEDULER_TaskContext *tc)
481 struct GNUNET_NETWORK_SocketHandle *sock = cls;
485 /* nobody needs to wait for us anymore... */
486 sock->connect_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
487 /* Note: write-ready does NOT mean connect succeeded,
488 we need to use getsockopt to be sure */
489 len = sizeof (error);
492 if ((0 == (tc->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) ||
493 (0 != getsockopt (sock->sock, SOL_SOCKET, SO_ERROR, &error, &len)) ||
494 (error != 0) || (errno != 0))
496 /* connect failed / timed out */
497 GNUNET_break (0 == CLOSE (sock->sock));
499 if (GNUNET_SYSERR == try_connect (sock))
501 /* failed for good */
502 GNUNET_break (sock->ai_pos == NULL);
503 freeaddrinfo (sock->ai);
507 sock->connect_task = GNUNET_SCHEDULER_add_write (tc->sched, GNUNET_NO, /* abort on shutdown */
508 GNUNET_SCHEDULER_PRIORITY_KEEP,
509 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
510 GNUNET_NETWORK_CONNECT_RETRY_TIMEOUT,
512 &connect_continuation,
516 /* connect succeeded! clean up "ai" */
518 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connection succeeded!\n");
520 freeaddrinfo (sock->ai);
527 * Create a socket handle by (asynchronously) connecting to a host.
528 * This function returns immediately, even if the connection has not
529 * yet been established. This function only creates TCP connections.
531 * @param sched scheduler to use
532 * @param hostname name of the host to connect to
533 * @param port port to connect to
534 * @param maxbuf maximum write buffer size for the socket (use
535 * 0 for sockets that need no write buffers, such as listen sockets)
536 * @return the socket handle
538 struct GNUNET_NETWORK_SocketHandle *
539 GNUNET_NETWORK_socket_create_from_connect (struct GNUNET_SCHEDULER_Handle
540 *sched, const char *hostname,
541 uint16_t port, size_t maxbuf)
543 struct GNUNET_NETWORK_SocketHandle *ret;
544 struct addrinfo hints;
547 ret = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_SocketHandle) + maxbuf);
550 ret->write_buffer = (char *) &ret[1];
551 ret->write_buffer_size = maxbuf;
553 memset (&hints, 0, sizeof (hints));
554 hints.ai_family = AF_UNSPEC;
555 hints.ai_socktype = SOCK_STREAM;
556 if (0 != (ec = getaddrinfo (hostname, NULL, &hints, &ret->ai)))
558 GNUNET_log (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
559 "`%s' failed for hostname `%s': %s\n",
560 "getaddrinfo", hostname, gai_strerror (ec));
564 ret->ai_pos = ret->ai;
565 if (GNUNET_SYSERR == try_connect (ret))
567 freeaddrinfo (ret->ai);
571 ret->connect_task = GNUNET_SCHEDULER_add_write (sched, GNUNET_NO, /* abort on shutdown */
572 GNUNET_SCHEDULER_PRIORITY_KEEP,
573 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
574 GNUNET_NETWORK_CONNECT_RETRY_TIMEOUT,
576 &connect_continuation, ret);
583 * Create a socket handle by (asynchronously) connecting to a host.
584 * This function returns immediately, even if the connection has not
585 * yet been established. This function only creates TCP connections.
587 * @param sched scheduler to use
588 * @param af_family address family to use
589 * @param serv_addr server address
590 * @param addrlen length of server address
591 * @param maxbuf maximum write buffer size for the socket (use
592 * 0 for sockets that need no write buffers, such as listen sockets)
593 * @return the socket handle
595 struct GNUNET_NETWORK_SocketHandle *
596 GNUNET_NETWORK_socket_create_from_sockaddr (struct GNUNET_SCHEDULER_Handle
597 *sched, int af_family,
598 const struct sockaddr *serv_addr,
599 socklen_t addrlen, size_t maxbuf)
603 s = SOCKET (af_family, SOCK_STREAM, 0);
606 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING |
607 GNUNET_ERROR_TYPE_BULK, "socket");
610 if (0 != fcntl (s, F_SETFD, fcntl (s, F_GETFD) | FD_CLOEXEC))
611 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
613 if (GNUNET_SYSERR == socket_set_blocking (s, GNUNET_NO))
615 /* we'll treat this one as fatal */
616 GNUNET_break (0 == CLOSE (s));
619 if ((0 != CONNECT (s, serv_addr, addrlen)) && (errno != EINPROGRESS))
621 /* maybe refused / unsupported address, try next */
622 GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "connect");
623 GNUNET_break (0 == CLOSE (s));
626 return GNUNET_NETWORK_socket_create_from_existing (sched, s, maxbuf);
631 * Check if socket is valid (no fatal errors have happened so far).
632 * Note that a socket that is still trying to connect is considered
635 * @param sock socket to check
636 * @return GNUNET_YES if valid, GNUNET_NO otherwise
639 GNUNET_NETWORK_socket_check (struct GNUNET_NETWORK_SocketHandle *sock)
641 if (sock->ai != NULL)
642 return GNUNET_YES; /* still trying to connect */
643 return (sock->sock == -1) ? GNUNET_NO : GNUNET_YES;
648 * Scheduler let us know that the connect task is finished (or was
649 * cancelled due to shutdown). Now really clean up.
652 destroy_continuation (void *cls,
653 const struct GNUNET_SCHEDULER_TaskContext *tc)
655 struct GNUNET_NETWORK_SocketHandle *sock = cls;
656 GNUNET_NETWORK_TransmitReadyNotify notify;
658 if (sock->write_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
661 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
662 "Destroy code waiting for writes to complete.\n");
664 GNUNET_SCHEDULER_add_after (sock->sched,
666 GNUNET_SCHEDULER_PRIORITY_KEEP,
668 &destroy_continuation, sock);
671 if (sock->sock != -1)
674 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Shutting down socket.\n");
676 SHUTDOWN (sock->sock, SHUT_RDWR);
678 if (sock->read_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
681 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
682 "Destroy code waiting for receive to complete.\n");
684 GNUNET_SCHEDULER_add_after (sock->sched,
686 GNUNET_SCHEDULER_PRIORITY_KEEP,
688 &destroy_continuation, sock);
691 if (NULL != (notify = sock->nth.notify_ready))
693 sock->nth.notify_ready = NULL;
694 notify (sock->nth.notify_ready_cls, 0, NULL);
695 if (sock->nth.timeout_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
697 GNUNET_SCHEDULER_cancel (sock->sched, sock->nth.timeout_task);
698 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
701 if (sock->sock != -1)
704 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Closing socket.\n");
706 GNUNET_break (0 == CLOSE (sock->sock));
708 GNUNET_free_non_null (sock->addr);
709 if (sock->ai != NULL)
710 freeaddrinfo (sock->ai);
716 * Close the socket and free associated resources. Pending
717 * transmissions are simply dropped. A pending receive call will be
718 * called with an error code of "EPIPE".
720 * @param sock socket to destroy
723 GNUNET_NETWORK_socket_destroy (struct GNUNET_NETWORK_SocketHandle *sock)
726 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
727 "Network asked to destroy socket %p\n", sock);
729 if (sock->write_buffer_off == 0)
730 sock->ai_pos = NULL; /* if we're still trying to connect and have
731 no message pending, stop trying! */
732 GNUNET_assert (sock->sched != NULL);
733 GNUNET_SCHEDULER_add_after (sock->sched,
735 GNUNET_SCHEDULER_PRIORITY_KEEP,
737 &destroy_continuation, sock);
741 * Tell the receiver callback that a timeout was reached.
744 signal_timeout (struct GNUNET_NETWORK_SocketHandle *sh)
746 GNUNET_NETWORK_Receiver receiver;
749 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
750 "Network signals timeout to receiver!\n");
752 GNUNET_assert (NULL != (receiver = sh->receiver));
754 receiver (sh->receiver_cls, NULL, 0, NULL, 0, 0);
759 * Tell the receiver callback that we had an IO error.
762 signal_error (struct GNUNET_NETWORK_SocketHandle *sh, int errcode)
764 GNUNET_NETWORK_Receiver receiver;
765 GNUNET_assert (NULL != (receiver = sh->receiver));
767 receiver (sh->receiver_cls, NULL, 0, sh->addr, sh->addrlen, errcode);
772 * This function is called once we either timeout
773 * or have data ready to read.
776 receive_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
778 struct GNUNET_NETWORK_SocketHandle *sh = cls;
779 struct GNUNET_TIME_Absolute now;
780 char buffer[sh->max];
782 GNUNET_NETWORK_Receiver receiver;
784 sh->read_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
785 now = GNUNET_TIME_absolute_get ();
786 if ((now.value > sh->receive_timeout.value) ||
787 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_TIMEOUT)) ||
788 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
791 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
792 "Receive encounters error: timeout...\n");
799 /* connect failed for good */
801 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
802 "Receive encounters error, socket closed...\n");
804 signal_error (sh, ECONNREFUSED);
807 GNUNET_assert (FD_ISSET (sh->sock, tc->read_ready));
809 ret = RECV (sh->sock, buffer, sh->max, MSG_DONTWAIT);
815 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
816 "Error receiving: %s\n", STRERROR (errno));
818 signal_error (sh, errno);
822 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
823 "Receive got %d bytes from OS!\n", ret);
825 GNUNET_assert (NULL != (receiver = sh->receiver));
827 receiver (sh->receiver_cls, buffer, ret, sh->addr, sh->addrlen, 0);
832 * This function is called after establishing a connection either has
833 * succeeded or timed out. Note that it is possible that the attempt
834 * timed out and that we're immediately retrying. If we are retrying,
835 * we need to wait again (or timeout); if we succeeded, we need to
836 * wait for data (or timeout).
839 receive_again (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
841 struct GNUNET_NETWORK_SocketHandle *sh = cls;
842 struct GNUNET_TIME_Absolute now;
844 sh->read_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
845 if ((sh->sock == -1) &&
846 (sh->connect_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK))
848 /* not connected and no longer trying */
850 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
851 "Receive encounters error, socket closed...\n");
853 signal_error (sh, ECONNREFUSED);
856 now = GNUNET_TIME_absolute_get ();
857 if ((now.value > sh->receive_timeout.value) ||
858 (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
861 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
862 "Receive encounters error: timeout...\n");
867 if (sh->connect_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
869 /* connect was retried */
871 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
872 "Receive still waits on connect...\n");
874 sh->read_task = GNUNET_SCHEDULER_add_after (tc->sched,
876 GNUNET_SCHEDULER_PRIORITY_KEEP,
882 /* connect succeeded, wait for data! */
884 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
885 "Receive now waits for socket...\n");
887 sh->read_task = GNUNET_SCHEDULER_add_read (tc->sched,
889 GNUNET_SCHEDULER_PRIORITY_KEEP,
891 GNUNET_TIME_absolute_get_remaining
892 (sh->receive_timeout),
893 sh->sock, &receive_ready,
900 * Receive data from the given socket. Note that this function will
901 * call "receiver" asynchronously using the scheduler. It will
902 * "immediately" return. Note that there MUST only be one active
903 * receive call per socket at any given point in time (so do not
904 * call receive again until the receiver callback has been invoked).
906 * @param sched scheduler to use
907 * @param sock socket handle
908 * @param max maximum number of bytes to read
909 * @param timeout maximum amount of time to wait (use -1 for "forever")
910 * @param receiver function to call with received data
911 * @param receiver_cls closure for receiver
912 * @return scheduler task ID used for receiving, GNUNET_SCHEDULER_NO_PREREQUISITE_TASK on error
914 GNUNET_SCHEDULER_TaskIdentifier
915 GNUNET_NETWORK_receive (struct GNUNET_NETWORK_SocketHandle *sock,
917 struct GNUNET_TIME_Relative timeout,
918 GNUNET_NETWORK_Receiver receiver, void *receiver_cls)
920 struct GNUNET_SCHEDULER_TaskContext tc;
922 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
923 "Network asked to receive from socket...\n");
925 GNUNET_assert ((sock->read_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK) &&
926 (sock->receiver == NULL));
927 sock->receiver = receiver;
928 sock->receiver_cls = receiver_cls;
929 sock->receive_timeout = GNUNET_TIME_relative_to_absolute (timeout);
931 memset (&tc, 0, sizeof (tc));
932 tc.sched = sock->sched;
933 tc.reason = GNUNET_SCHEDULER_REASON_PREREQ_DONE;
934 receive_again (sock, &tc);
935 return sock->read_task;
940 * Cancel receive job on the given socket. Note that the
941 * receiver callback must not have been called yet in order
942 * for the cancellation to be valid.
944 * @param sock socket handle
945 * @param task task identifier returned from the receive call
946 * @return closure of the original receiver callback
949 GNUNET_NETWORK_receive_cancel (struct GNUNET_NETWORK_SocketHandle *sock,
950 GNUNET_SCHEDULER_TaskIdentifier task)
952 GNUNET_assert (sock->read_task == task);
953 GNUNET_assert (sock == GNUNET_SCHEDULER_cancel (sock->sched, task));
954 sock->read_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
955 sock->receiver = NULL;
956 return sock->receiver_cls;
961 * Try to call the transmit notify method (check if we do
962 * have enough space available first)!
964 * @param sock socket for which we should do this processing
965 * @return GNUNET_YES if we were able to call notify
968 process_notify (struct GNUNET_NETWORK_SocketHandle *sock)
973 GNUNET_NETWORK_TransmitReadyNotify notify;
975 GNUNET_assert (sock->write_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK);
976 if (NULL == (notify = sock->nth.notify_ready))
978 used = sock->write_buffer_off - sock->write_buffer_pos;
979 avail = sock->write_buffer_size - used;
980 size = sock->nth.notify_size;
981 if (sock->nth.notify_size > avail)
983 sock->nth.notify_ready = NULL;
984 if (sock->nth.timeout_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
986 GNUNET_SCHEDULER_cancel (sock->sched, sock->nth.timeout_task);
987 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
989 if (sock->write_buffer_size - sock->write_buffer_off < size)
991 /* need to compact */
992 memmove (sock->write_buffer,
993 &sock->write_buffer[sock->write_buffer_pos], used);
994 sock->write_buffer_off -= sock->write_buffer_pos;
995 sock->write_buffer_pos = 0;
997 GNUNET_assert (sock->write_buffer_size - sock->write_buffer_off >= size);
998 size = notify (sock->nth.notify_ready_cls,
999 sock->write_buffer_size - sock->write_buffer_off,
1000 &sock->write_buffer[sock->write_buffer_off]);
1001 sock->write_buffer_off += size;
1007 * Task invoked by the scheduler when a call to transmit
1008 * is timing out (we never got enough buffer space to call
1009 * the callback function before the specified timeout
1012 * This task notifies the client about the timeout.
1015 transmit_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1017 struct GNUNET_NETWORK_SocketHandle *sock = cls;
1018 GNUNET_NETWORK_TransmitReadyNotify notify;
1021 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmit fails, time out reached.\n");
1023 notify = sock->nth.notify_ready;
1024 sock->nth.notify_ready = NULL;
1025 notify (sock->nth.notify_ready_cls, 0, NULL);
1030 transmit_error (struct GNUNET_NETWORK_SocketHandle *sock)
1032 if (sock->nth.notify_ready == NULL)
1033 return; /* nobody to tell about it */
1034 if (sock->nth.timeout_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1036 GNUNET_SCHEDULER_cancel (sock->sched, sock->nth.timeout_task);
1037 sock->nth.timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1039 transmit_timeout (sock, NULL);
1044 * See if we are now connected. If not, wait longer for
1045 * connect to succeed. If connected, we should be able
1046 * to write now as well, unless we timed out.
1049 transmit_ready (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1051 struct GNUNET_NETWORK_SocketHandle *sock = cls;
1056 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1057 "Transmit ready called --- will try to send\n");
1059 GNUNET_assert (sock->write_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK);
1060 sock->write_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1061 if (sock->connect_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1063 /* still waiting for connect */
1065 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1066 "Transmission still waiting for connect...\n");
1068 GNUNET_assert (sock->write_task ==
1069 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK);
1071 GNUNET_SCHEDULER_add_delayed (tc->sched, GNUNET_NO,
1072 GNUNET_SCHEDULER_PRIORITY_KEEP,
1074 GNUNET_TIME_UNIT_ZERO, &transmit_ready,
1078 if (sock->sock == -1)
1080 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1082 ("Did not transmit request, socket closed or connect failed.\n"));
1083 transmit_error (sock);
1084 return; /* connect failed for good, we're finished */
1086 if ((tc->write_ready == NULL) || (!FD_ISSET (sock->sock, tc->write_ready)))
1089 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1090 "Socket not yet ready for writing, will wait for that.\n");
1092 goto SCHEDULE_WRITE;
1094 GNUNET_assert (sock->write_buffer_off >= sock->write_buffer_pos);
1095 process_notify (sock);
1096 have = sock->write_buffer_off - sock->write_buffer_pos;
1100 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "No data ready for writing.\n");
1105 ret = SEND (sock->sock,
1106 &sock->write_buffer[sock->write_buffer_pos],
1107 have, MSG_DONTWAIT | MSG_NOSIGNAL);
1113 GNUNET_log_strerror (GNUNET_ERROR_TYPE_DEBUG, "send");
1115 SHUTDOWN (sock->sock, SHUT_RDWR);
1116 GNUNET_break (0 == CLOSE (sock->sock));
1118 transmit_error (sock);
1122 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitted %d bytes to OS\n", ret);
1124 sock->write_buffer_pos += ret;
1125 if (sock->write_buffer_pos == sock->write_buffer_off)
1127 /* transmitted all pending data */
1128 sock->write_buffer_pos = 0;
1129 sock->write_buffer_off = 0;
1131 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1132 "Transmission buffer now empty.\n", ret);
1135 if ((sock->write_buffer_off == 0) && (NULL == sock->nth.notify_ready))
1136 return; /* all data sent! */
1137 /* not done writing, schedule more */
1139 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1140 "More data ready for transmission, scheduling task again!\n");
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 "Transmit 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,
1206 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1207 "Scheduling asynchronous transmission once connect is done...\n");
1209 if (sock->write_task == GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1210 sock->write_task = GNUNET_SCHEDULER_add_delayed (sock->sched,
1212 GNUNET_SCHEDULER_PRIORITY_KEEP,
1214 GNUNET_TIME_UNIT_ZERO,
1215 &transmit_ready, sock);
1221 * Cancel the specified transmission-ready
1225 GNUNET_NETWORK_notify_transmit_ready_cancel (struct
1226 GNUNET_NETWORK_TransmitHandle *h)
1228 GNUNET_assert (h->notify_ready != NULL);
1229 GNUNET_SCHEDULER_cancel (h->sh->sched, h->timeout_task);
1230 h->timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1231 h->notify_ready = NULL;
1235 #if 0 /* keep Emacsens' auto-indent happy */