2.11BSD#431 - /usr/src/ucb/talk/io.c

   1: /*
   2:  * Copyright (c) 1983 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #if !defined(lint) && defined(DOSCCS)
   8: static char sccsid[] = "@(#)io.c	5.1.1 (2.11BSD) 1996/3/22";
   9: #endif
  10: 
  11: /*
  12:  * This file contains the I/O handling and the exchange of
  13:  * edit characters. This connection itself is established in
  14:  * ctl.c
  15:  */
  16: 
  17: #include "talk.h"
  18: #include <stdio.h>
  19: #include <errno.h>
  20: #include <string.h>
  21: #include <sys/time.h>
  22: 
  23: #define A_LONG_TIME 10000000
  24: #define STDIN_MASK (1L<<fileno(stdin))  /* the bit mask for standard
  25: 					   input */
  26: extern int errno;
  27: 
  28: /*
  29:  * The routine to do the actual talking
  30:  */
  31: talk()
  32: {
  33:     register long read_template, sockt_mask;
  34:     long read_set;
  35:     int nb;
  36:     long nbl;
  37:     char buf[BUFSIZ];
  38:     struct timeval wait;
  39: 
  40:     message("Connection established\007\007\007");
  41:     current_line = 0;
  42:     sockt_mask = (1L<<sockt);
  43: 
  44:     /*
  45: 	 * Wait on both the other process (sockt_mask) and
  46: 	 * standard input ( STDIN_MASK )
  47: 	 */
  48:     read_template = sockt_mask | STDIN_MASK;
  49:     forever {
  50:         read_set = read_template;
  51:         wait.tv_sec = A_LONG_TIME;
  52:         wait.tv_usec = 0;
  53:         nb = select(32, &read_set, (long *)0, (long *)0, &wait);
  54:         if (nb <= 0) {
  55:             if (errno == EINTR) {
  56:                 read_set = read_template;
  57:                 continue;
  58:             }
  59:             /* panic, we don't know what happened */
  60:             p_error("Unexpected error from select");
  61:             quit();
  62:         }
  63:         if (read_set & sockt_mask) {
  64:             /* There is data on sockt */
  65:             nb = read(sockt, buf, sizeof buf);
  66:             if (nb <= 0) {
  67:                 message("Connection closed. Exiting");
  68:                 quit();
  69:             }
  70:             display(&his_win, buf, nb);
  71:         }
  72:         if (read_set & STDIN_MASK) {
  73:             /*
  74: 			 * We can't make the tty non_blocking, because
  75: 			 * curses's output routines would screw up
  76: 			 */
  77:             ioctl(0, FIONREAD, (struct sgttyb *) &nbl);
  78:             nb = read(0, buf, (int)nbl);
  79:             display(&my_win, buf, nb);
  80:             /* might lose data here because sockt is non-blocking */
  81:             write(sockt, buf, nb);
  82:         }
  83:     }
  84: }
  85: 
  86: /*
  87:  * p_error prints the system error message on the standard location
  88:  * on the screen and then exits. (i.e. a curses version of perror)
  89:  */
  90: p_error(string)
  91:     char *string;
  92: {
  93:     char *sys;
  94: 
  95:     sys = strerror(errno);
  96:     wmove(my_win.x_win, current_line%my_win.x_nlines, 0);
  97:     wprintw(my_win.x_win, "[%s : %s (%d)]\n", string, sys, errno);
  98:     wrefresh(my_win.x_win);
  99:     move(LINES-1, 0);
 100:     refresh();
 101:     quit();
 102: }
 103: 
 104: /*
 105:  * Display string in the standard location
 106:  */
 107: message(string)
 108:     char *string;
 109: {
 110: 
 111:     wmove(my_win.x_win, current_line%my_win.x_nlines, 0);
 112:     wprintw(my_win.x_win, "[%s]\n", string);
 113:     wrefresh(my_win.x_win);
 114: }

Defined functions

Defined variables

Defined macros