talkd.tproj/talkd.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1983, 1993
  27  *      The Regents of the University of California.  All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  */
  57
  58 #ifndef lint
  59 static char copyright[] =
  60 "@(#) Copyright (c) 1983, 1993\n\
  61         The Regents of the University of California.  All rights reserved.\n";
  62 #endif /* not lint */
  63
  64 #ifndef lint
  65 static char sccsid[] = "@(#)talkd.c     8.1 (Berkeley) 6/4/93";
  66 #endif /* not lint */
  67
  68 /*
  69  * The top level of the daemon, the format is heavily borrowed
  70  * from rwhod.c. Basically: find out who and where you are;
  71  * disconnect all descriptors and ttys, and then endless
  72  * loop on waiting for and processing requests
  73  */
  74 #include <sys/types.h>
  75 #include <sys/socket.h>
  76 #include <protocols/talkd.h>
  77 #include <signal.h>
  78 #include <syslog.h>
  79 #include <time.h>
  80 #include <errno.h>
  81 #include <unistd.h>
  82 #include <stdio.h>
  83 #include <stdlib.h>
  84 #include <string.h>
  85 #include <paths.h>
  86 #include <sys/param.h>
  87 #include "talkd.h"
  88
  89 CTL_MSG         request;
  90 CTL_RESPONSE    response;
  91
  92 int     sockt;
  93 int     debug = 0;
  94 void    timeout();
  95 long    lastmsgtime;
  96
  97 char    hostname[MAXHOSTNAMELEN + 1];
  98
  99 #define TIMEOUT 30
 100 #define MAXIDLE 120
 101
 102 void
 103 main(argc, argv)
 104         int argc;
 105         char *argv[];
 106 {
 107         register CTL_MSG *mp = &request;
 108         int cc;
 109
 110         if (getuid()) {
 111                 fprintf(stderr, "%s: getuid: not super-user\n", argv[0]);
 112                 exit(1);
 113         }
 114         openlog("talkd", LOG_PID, LOG_DAEMON);
 115         if (gethostname(hostname, sizeof (hostname) - 1) < 0) {
 116                 syslog(LOG_ERR, "gethostname: %m");
 117                 _exit(1);
 118         }
 119         if (chdir(_PATH_DEV) < 0) {
 120                 syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
 121                 _exit(1);
 122         }
 123         if (argc > 1 && strcmp(argv[1], "-d") == 0)
 124                 debug = 1;
 125         signal(SIGALRM, timeout);
 126         alarm(TIMEOUT);
 127         for (;;) {
 128                 extern int errno;
 129
 130                 cc = recv(0, (char *)mp, sizeof (*mp), 0);
 131                 if (cc != sizeof (*mp)) {
 132                         if (cc < 0 && errno != EINTR)
 133                                 syslog(LOG_WARNING, "recv: %m");
 134                         continue;
 135                 }
 136                 lastmsgtime = time(0);
 137                 process_request(mp, &response);
 138                 /* can block here, is this what I want? */
 139                 cc = sendto(sockt, (char *)&response,
 140                     sizeof (response), 0, (struct sockaddr *)&mp->ctl_addr,
 141                     sizeof (mp->ctl_addr));
 142                 if (cc != sizeof (response))
 143                         syslog(LOG_WARNING, "sendto: %m");
 144         }
 145 }
 146
 147 void
 148 timeout()
 149 {
 150
 151         if (time(0) - lastmsgtime >= MAXIDLE)
 152                 _exit(0);
 153         alarm(TIMEOUT);
 154 }