usr.bin/talk/io.c

   1 /*
   2  * Copyright (c) 1983, 1993
   3  *      The Regents of the University of California.  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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)io.c     8.1 (Berkeley) 6/6/93
  30  * $FreeBSD: src/usr.bin/talk/io.c,v 1.9.2.2 2001/10/15 13:42:07 dd Exp $
  31  */
  32
  33 /*
  34  * This file contains the I/O handling and the exchange of
  35  * edit characters. This connection itself is established in
  36  * ctl.c
  37  */
  38
  39 #include <errno.h>
  40 #include <netdb.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <sys/filio.h>
  44 #include "talk.h"
  45 #include "talk_ctl.h"
  46
  47 #define A_LONG_TIME 10000000
  48
  49 /*
  50  * The routine to do the actual talking
  51  */
  52 void
  53 talk(void)
  54 {
  55         struct hostent *hp, *hp2;
  56         int nb;
  57         fd_set read_set, read_template;
  58         char buf[BUFSIZ], **addr, *his_machine_name;
  59         struct timeval wait;
  60
  61         his_machine_name = NULL;
  62         hp = gethostbyaddr(&his_machine_addr.s_addr,
  63             sizeof(his_machine_addr.s_addr), AF_INET);
  64         if (hp != NULL) {
  65                 hp2 = gethostbyname(hp->h_name);
  66                 if (hp2 != NULL && hp2->h_addrtype == AF_INET &&
  67                     hp2->h_length == sizeof(his_machine_addr))
  68                         for (addr = hp2->h_addr_list; *addr != NULL; addr++)
  69                                 if (memcmp(*addr, &his_machine_addr,
  70                                     sizeof(his_machine_addr)) == 0) {
  71                                         his_machine_name = strdup(hp->h_name);
  72                                         break;
  73                                 }
  74         }
  75         if (his_machine_name == NULL)
  76                 his_machine_name = strdup(inet_ntoa(his_machine_addr));
  77         snprintf(buf, sizeof(buf), "Connection established with %s@%s.",
  78             msg.r_name, his_machine_name);
  79         free(his_machine_name);
  80         message(buf);
  81         write(STDOUT_FILENO, "\007\007\007", 3);
  82
  83         current_line = 0;
  84
  85         /*
  86          * Wait on both the other process (sockt_mask) and
  87          * standard input ( STDIN_MASK )
  88          */
  89         FD_ZERO(&read_template);
  90         FD_SET(sockt, &read_template);
  91         FD_SET(fileno(stdin), &read_template);
  92         for (;;) {
  93                 read_set = read_template;
  94                 wait.tv_sec = A_LONG_TIME;
  95                 wait.tv_usec = 0;
  96                 nb = select(32, &read_set, 0, 0, &wait);
  97                 if (nb <= 0) {
  98                         if (errno == EINTR) {
  99                                 read_set = read_template;
 100                                 continue;
 101                         }
 102                         /* panic, we don't know what happened */
 103                         p_error("Unexpected error from select");
 104                         quit();
 105                 }
 106                 if (FD_ISSET(sockt, &read_set)) {
 107                         /* There is data on sockt */
 108                         nb = read(sockt, buf, sizeof buf);
 109                         if (nb <= 0) {
 110                                 message("Connection closed. Exiting");
 111                                 quit();
 112                         }
 113                         display(&his_win, buf, nb);
 114                 }
 115                 if (FD_ISSET(fileno(stdin), &read_set)) {
 116                         /*
 117                          * We can't make the tty non_blocking, because
 118                          * curses's output routines would screw up
 119                          */
 120                         int i;
 121                         ioctl(0, FIONREAD, (struct sgttyb *) &nb);
 122                         nb = read(0, buf, nb);
 123                         display(&my_win, buf, nb);
 124                         /* might lose data here because sockt is non-blocking */
 125                         for (i = 0; i < nb; ++i)
 126                                 if (buf[i] == '\r')
 127                                         buf[i] = '\n';
 128                         write(sockt, buf, nb);
 129                 }
 130         }
 131 }
 132
 133 /*
 134  * p_error prints the system error message on the standard location
 135  * on the screen and then exits. (i.e. a curses version of perror)
 136  */
 137 void
 138 p_error(const char *string)
 139 {
 140         wmove(my_win.x_win, current_line, 0);
 141         wprintw(my_win.x_win, "[%s : %s (%d)]\n",
 142             string, strerror(errno), errno);
 143         wrefresh(my_win.x_win);
 144         move(LINES-1, 0);
 145         refresh();
 146         quit();
 147 }
 148
 149 /*
 150  * Display string in the standard location
 151  */
 152 void
 153 message(const char *string)
 154 {
 155         wmove(my_win.x_win, current_line, 0);
 156         wprintw(my_win.x_win, "[%s]\n", string);
 157         if (current_line < my_win.x_nlines - 1)
 158                 current_line++;
 159         wrefresh(my_win.x_win);
 160 }