diff options
Diffstat (limited to 'usr.bin/talk/look_up.c')
| -rw-r--r-- | usr.bin/talk/look_up.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/usr.bin/talk/look_up.c b/usr.bin/talk/look_up.c new file mode 100644 index 0000000..9c335ae --- /dev/null +++ b/usr.bin/talk/look_up.c @@ -0,0 +1,115 @@ +/* + * Copyright (c) 1983, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static char sccsid[] = "@(#)look_up.c 8.1 (Berkeley) 6/6/93"; +#endif /* not lint */ + +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <protocols/talkd.h> +#include <errno.h> +#include "talk_ctl.h" +#include "talk.h" + +/* + * See if the local daemon has an invitation for us. + */ +check_local() +{ + CTL_RESPONSE response; + register CTL_RESPONSE *rp = &response; + + /* the rest of msg was set up in get_names */ +#ifdef MSG_EOR + /* copy new style sockaddr to old, swap family (short in old) */ + msg.ctl_addr = *(struct osockaddr *)&ctl_addr; + msg.ctl_addr.sa_family = htons(ctl_addr.sin_family); +#else + msg.ctl_addr = *(struct sockaddr *)&ctl_addr; +#endif + /* must be initiating a talk */ + if (!look_for_invite(rp)) + return (0); + /* + * There was an invitation waiting for us, + * so connect with the other (hopefully waiting) party + */ + current_state = "Waiting to connect with caller"; + do { + if (rp->addr.sa_family != AF_INET) + p_error("Response uses invalid network address"); + errno = 0; + if (connect(sockt, + (struct sockaddr *)&rp->addr, sizeof (rp->addr)) != -1) + return (1); + } while (errno == EINTR); + if (errno == ECONNREFUSED) { + /* + * The caller gave up, but his invitation somehow + * was not cleared. Clear it and initiate an + * invitation. (We know there are no newer invitations, + * the talkd works LIFO.) + */ + ctl_transact(his_machine_addr, msg, DELETE, rp); + close(sockt); + open_sockt(); + return (0); + } + p_error("Unable to connect with initiator"); + /*NOTREACHED*/ +} + +/* + * Look for an invitation on 'machine' + */ +look_for_invite(rp) + CTL_RESPONSE *rp; +{ + struct in_addr machine_addr; + + current_state = "Checking for invitation on caller's machine"; + ctl_transact(his_machine_addr, msg, LOOK_UP, rp); + /* the switch is for later options, such as multiple invitations */ + switch (rp->answer) { + + case SUCCESS: + msg.id_num = htonl(rp->id_num); + return (1); + + default: + /* there wasn't an invitation waiting for us */ + return (0); + } +} |
