announce.c revision 1.6
1 /* 2 * Copyright (c) 1983 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 /*static char sccsid[] = "from: @(#)announce.c 5.9 (Berkeley) 2/26/91";*/ 36 static char rcsid[] = "$Id: announce.c,v 1.6 1996/07/17 18:46:58 rat Exp $"; 37 #endif /* not lint */ 38 39 #include <sys/types.h> 40 #include <sys/stat.h> 41 #include <sys/time.h> 42 #include <sys/wait.h> 43 #include <sys/socket.h> 44 #include <protocols/talkd.h> 45 #include <sgtty.h> 46 #include <errno.h> 47 #include <syslog.h> 48 #include <unistd.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include <vis.h> 53 #include <paths.h> 54 55 extern char hostname[]; 56 57 /* 58 * Announce an invitation to talk. 59 * 60 * Because the tty driver insists on attaching a terminal-less 61 * process to any terminal that it writes on, we must fork a child 62 * to protect ourselves 63 */ 64 announce(request, remote_machine) 65 CTL_MSG *request; 66 char *remote_machine; 67 { 68 int pid, val, status; 69 70 if (pid = fork()) { 71 /* we are the parent, so wait for the child */ 72 if (pid == -1) /* the fork failed */ 73 return (FAILED); 74 do { 75 val = wait(&status); 76 if (val == -1) { 77 if (errno == EINTR) 78 continue; 79 /* shouldn't happen */ 80 syslog(LOG_WARNING, "announce: wait: %m"); 81 return (FAILED); 82 } 83 } while (val != pid); 84 if (status&0377 > 0) /* we were killed by some signal */ 85 return (FAILED); 86 /* Get the second byte, this is the exit/return code */ 87 return ((status >> 8) & 0377); 88 } 89 /* we are the child, go and do it */ 90 _exit(announce_proc(request, remote_machine)); 91 } 92 93 /* 94 * See if the user is accepting messages. If so, announce that 95 * a talk is requested. 96 */ 97 announce_proc(request, remote_machine) 98 CTL_MSG *request; 99 char *remote_machine; 100 { 101 int pid, status; 102 char full_tty[32]; 103 FILE *tf; 104 struct stat stbuf; 105 106 (void)snprintf(full_tty, sizeof(full_tty), "%s/%s", _PATH_DEV, 107 request->r_tty); 108 if (access(full_tty, 0) != 0) 109 return (FAILED); 110 if ((tf = fopen(full_tty, "w")) == NULL) 111 return (PERMISSION_DENIED); 112 /* 113 * On first tty open, the server will have 114 * it's pgrp set, so disconnect us from the 115 * tty before we catch a signal. 116 */ 117 ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0); 118 if (fstat(fileno(tf), &stbuf) < 0) 119 return (PERMISSION_DENIED); 120 if ((stbuf.st_mode&020) == 0) 121 return (PERMISSION_DENIED); 122 print_mesg(tf, request, remote_machine); 123 fclose(tf); 124 return (SUCCESS); 125 } 126 127 #define max(a,b) ( (a) > (b) ? (a) : (b) ) 128 #define N_LINES 5 129 #define N_CHARS 120 130 131 /* 132 * Build a block of characters containing the message. 133 * It is sent blank filled and in a single block to 134 * try to keep the message in one piece if the recipient 135 * in in vi at the time 136 */ 137 print_mesg(tf, request, remote_machine) 138 FILE *tf; 139 CTL_MSG *request; 140 char *remote_machine; 141 { 142 struct timeval clock; 143 time_t clocktime; 144 struct timezone zone; 145 struct tm *localclock; 146 char line_buf[N_LINES][N_CHARS]; 147 int sizes[N_LINES]; 148 char big_buf[N_LINES*N_CHARS]; 149 char *bptr, *lptr, *vis_user; 150 int i, j, max_size; 151 152 i = 0; 153 max_size = 0; 154 gettimeofday(&clock, &zone); 155 clocktime = clock.tv_sec; 156 localclock = localtime(&clocktime); 157 (void)snprintf(line_buf[i], N_CHARS, " "); 158 sizes[i] = strlen(line_buf[i]); 159 max_size = max(max_size, sizes[i]); 160 i++; 161 (void)snprintf(line_buf[i], N_CHARS, 162 "Message from Talk_Daemon@%s at %d:%02d ...", 163 hostname, localclock->tm_hour , localclock->tm_min ); 164 sizes[i] = strlen(line_buf[i]); 165 max_size = max(max_size, sizes[i]); 166 i++; 167 vis_user = (char *) malloc(strlen(request->l_name) * 4 + 1); 168 strvis(vis_user, request->l_name, VIS_CSTYLE); 169 (void)snprintf(line_buf[i], N_CHARS, 170 "talk: connection requested by %s@%s.", vis_user, remote_machine); 171 sizes[i] = strlen(line_buf[i]); 172 max_size = max(max_size, sizes[i]); 173 i++; 174 (void)snprintf(line_buf[i], N_CHARS, 175 "talk: respond with: talk %s@%s", vis_user, remote_machine); 176 sizes[i] = strlen(line_buf[i]); 177 max_size = max(max_size, sizes[i]); 178 i++; 179 (void)snprintf(line_buf[i], N_CHARS, " "); 180 sizes[i] = strlen(line_buf[i]); 181 max_size = max(max_size, sizes[i]); 182 i++; 183 bptr = big_buf; 184 *bptr++ = ''; /* send something to wake them up */ 185 *bptr++ = '\r'; /* add a \r in case of raw mode */ 186 *bptr++ = '\n'; 187 for (i = 0; i < N_LINES; i++) { 188 /* copy the line into the big buffer */ 189 lptr = line_buf[i]; 190 while (*lptr != '\0') 191 *(bptr++) = *(lptr++); 192 /* pad out the rest of the lines with blanks */ 193 for (j = sizes[i]; j < max_size + 2; j++) 194 *(bptr++) = ' '; 195 *(bptr++) = '\r'; /* add a \r in case of raw mode */ 196 *(bptr++) = '\n'; 197 } 198 *bptr = '\0'; 199 fprintf(tf, big_buf); 200 fflush(tf); 201 ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0); 202 } 203
Indexes created Fri Sep 26 20:09:58 GMT 2025