usr.bin/talk/display.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  * @(#)display.c        8.1 (Berkeley) 6/6/93
  30  * $FreeBSD: src/usr.bin/talk/display.c,v 1.7 1999/08/28 01:06:11 peter Exp $
  31  * $DragonFly: src/usr.bin/talk/display.c,v 1.4 2003/10/04 20:36:52 hmp Exp $
  32  */
  33
  34 /*
  35  * The window 'manager', initializes curses and handles the actual
  36  * displaying of text
  37  */
  38 #include "talk.h"
  39 #include <ctype.h>
  40
  41 xwin_t  my_win;
  42 xwin_t  his_win;
  43 WINDOW  *line_win;
  44
  45 int     curses_initialized = 0;
  46
  47 /*
  48  * max HAS to be a function, it is called with
  49  * an argument of the form --foo at least once.
  50  */
  51 int
  52 max(int a, int b)
  53 {
  54
  55         return (a > b ? a : b);
  56 }
  57
  58 /*
  59  * Display some text on somebody's window, processing some control
  60  * characters while we are at it.
  61  */
  62 void
  63 display(xwin_t *win, char *text, int size)
  64 {
  65         int i;
  66         char cch;
  67
  68         for (i = 0; i < size; i++) {
  69                 if (*text == '\n' || *text == '\r') {
  70                         waddch(win->x_win, '\n');
  71                         getyx(win->x_win, win->x_line, win->x_col);
  72                         text++;
  73                         continue;
  74                 }
  75                 if (*text == 004 && win == &my_win) {
  76                         /* control-D clears the screen */
  77                         werase(my_win.x_win);
  78                         getyx(my_win.x_win, my_win.x_line, my_win.x_col);
  79                         wrefresh(my_win.x_win);
  80                         werase(his_win.x_win);
  81                         getyx(his_win.x_win, his_win.x_line, his_win.x_col);
  82                         wrefresh(his_win.x_win);
  83                         text++;
  84                         continue;
  85                 }
  86
  87                 /* erase character */
  88                 if (   *text == win->cerase
  89                     || *text == 010     /* BS */
  90                     || *text == 0177    /* DEL */
  91                    ) {
  92                         wmove(win->x_win, win->x_line, max(--win->x_col, 0));
  93                         getyx(win->x_win, win->x_line, win->x_col);
  94                         waddch(win->x_win, ' ');
  95                         wmove(win->x_win, win->x_line, win->x_col);
  96                         getyx(win->x_win, win->x_line, win->x_col);
  97                         text++;
  98                         continue;
  99                 }
 100                 /*
 101                  * On word erase search backwards until we find
 102                  * the beginning of a word or the beginning of
 103                  * the line.
 104                  */
 105                 if (   *text == win->werase
 106                     || *text == 027     /* ^W */
 107                    ) {
 108                         int endcol, xcol, ii, c;
 109
 110                         endcol = win->x_col;
 111                         xcol = endcol - 1;
 112                         while (xcol >= 0) {
 113                                 c = readwin(win->x_win, win->x_line, xcol);
 114                                 if (c != ' ')
 115                                         break;
 116                                 xcol--;
 117                         }
 118                         while (xcol >= 0) {
 119                                 c = readwin(win->x_win, win->x_line, xcol);
 120                                 if (c == ' ')
 121                                         break;
 122                                 xcol--;
 123                         }
 124                         wmove(win->x_win, win->x_line, xcol + 1);
 125                         for (ii = xcol + 1; ii < endcol; ii++)
 126                                 waddch(win->x_win, ' ');
 127                         wmove(win->x_win, win->x_line, xcol + 1);
 128                         getyx(win->x_win, win->x_line, win->x_col);
 129                         text++;
 130                         continue;
 131                 }
 132                 /* line kill */
 133                 if (   *text == win->kill
 134                     || *text == 025     /* ^U */
 135                    ) {
 136                         wmove(win->x_win, win->x_line, 0);
 137                         wclrtoeol(win->x_win);
 138                         getyx(win->x_win, win->x_line, win->x_col);
 139                         text++;
 140                         continue;
 141                 }
 142                 if (*text == '\f') {
 143                         if (win == &my_win)
 144                                 wrefresh(curscr);
 145                         text++;
 146                         continue;
 147                 }
 148                 if (*text == '\7') {
 149                         write(STDOUT_FILENO, text, 1);
 150                         text++;
 151                         continue;
 152                 }
 153                 if (!isprint((unsigned char)*text) && *text != '\t') {
 154                         waddch(win->x_win, '^');
 155                         getyx(win->x_win, win->x_line, win->x_col);
 156                         cch = (*text & 63) + 64;
 157                         waddch(win->x_win, cch);
 158                 } else
 159                         waddch(win->x_win, (unsigned char)*text);
 160                 getyx(win->x_win, win->x_line, win->x_col);
 161                 text++;
 162         }
 163         wrefresh(win->x_win);
 164 }
 165
 166 /*
 167  * Read the character at the indicated position in win
 168  */
 169 int
 170 readwin(WINDOW *win, int line, int col)
 171 {
 172         int oldline, oldcol;
 173         int c;
 174
 175         getyx(win, oldline, oldcol);
 176         wmove(win, line, col);
 177         c = winch(win);
 178         wmove(win, oldline, oldcol);
 179         return (c);
 180 }