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. 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 #include <sys/cdefs.h>
  35
  36 __FBSDID("$FreeBSD$");
  37
  38 #ifndef lint
  39 static const char sccsid[] = "@(#)display.c     8.1 (Berkeley) 6/6/93";
  40 #endif
  41
  42 /*
  43  * The window 'manager', initializes curses and handles the actual
  44  * displaying of text
  45  */
  46 #include <ctype.h>
  47 #include <unistd.h>
  48
  49 #include "talk.h"
  50
  51 xwin_t  my_win;
  52 xwin_t  his_win;
  53 WINDOW  *line_win;
  54
  55 int     curses_initialized = 0;
  56
  57 /*
  58  * max HAS to be a function, it is called with
  59  * an argument of the form --foo at least once.
  60  */
  61 int
  62 max(int a, int b)
  63 {
  64
  65         return (a > b ? a : b);
  66 }
  67
  68 /*
  69  * Display some text on somebody's window, processing some control
  70  * characters while we are at it.
  71  */
  72 void
  73 display(xwin_t *win, char *text, int size)
  74 {
  75         int i;
  76         char cch;
  77
  78         for (i = 0; i < size; i++) {
  79                 if (*text == '\n' || *text == '\r') {
  80                         waddch(win->x_win, '\n');
  81                         getyx(win->x_win, win->x_line, win->x_col);
  82                         text++;
  83                         continue;
  84                 }
  85                 if (*text == 004 && win == &my_win) {
  86                         /* control-D clears the screen */
  87                         werase(my_win.x_win);
  88                         getyx(my_win.x_win, my_win.x_line, my_win.x_col);
  89                         wrefresh(my_win.x_win);
  90                         werase(his_win.x_win);
  91                         getyx(his_win.x_win, his_win.x_line, his_win.x_col);
  92                         wrefresh(his_win.x_win);
  93                         text++;
  94                         continue;
  95                 }
  96
  97                 /* erase character */
  98                 if (   *text == win->cerase
  99                     || *text == 010     /* BS */
 100                     || *text == 0177    /* DEL */
 101                    ) {
 102                         wmove(win->x_win, win->x_line, max(--win->x_col, 0));
 103                         getyx(win->x_win, win->x_line, win->x_col);
 104                         waddch(win->x_win, ' ');
 105                         wmove(win->x_win, win->x_line, win->x_col);
 106                         getyx(win->x_win, win->x_line, win->x_col);
 107                         text++;
 108                         continue;
 109                 }
 110                 /*
 111                  * On word erase search backwards until we find
 112                  * the beginning of a word or the beginning of
 113                  * the line.
 114                  */
 115                 if (   *text == win->werase
 116                     || *text == 027     /* ^W */
 117                    ) {
 118                         int endcol, xcol, ii, c;
 119
 120                         endcol = win->x_col;
 121                         xcol = endcol - 1;
 122                         while (xcol >= 0) {
 123                                 c = readwin(win->x_win, win->x_line, xcol);
 124                                 if (c != ' ')
 125                                         break;
 126                                 xcol--;
 127                         }
 128                         while (xcol >= 0) {
 129                                 c = readwin(win->x_win, win->x_line, xcol);
 130                                 if (c == ' ')
 131                                         break;
 132                                 xcol--;
 133                         }
 134                         wmove(win->x_win, win->x_line, xcol + 1);
 135                         for (ii = xcol + 1; ii < endcol; ii++)
 136                                 waddch(win->x_win, ' ');
 137                         wmove(win->x_win, win->x_line, xcol + 1);
 138                         getyx(win->x_win, win->x_line, win->x_col);
 139                         text++;
 140                         continue;
 141                 }
 142                 /* line kill */
 143                 if (   *text == win->kill
 144                     || *text == 025     /* ^U */
 145                    ) {
 146                         wmove(win->x_win, win->x_line, 0);
 147                         wclrtoeol(win->x_win);
 148                         getyx(win->x_win, win->x_line, win->x_col);
 149                         text++;
 150                         continue;
 151                 }
 152                 if (*text == '\f') {
 153                         if (win == &my_win)
 154                                 wrefresh(curscr);
 155                         text++;
 156                         continue;
 157                 }
 158                 if (*text == '\7') {
 159                         write(STDOUT_FILENO, text, 1);
 160                         text++;
 161                         continue;
 162                 }
 163                 if (!isprint((unsigned char)*text) && *text != '\t') {
 164                         waddch(win->x_win, '^');
 165                         getyx(win->x_win, win->x_line, win->x_col);
 166                         cch = (*text & 63) + 64;
 167                         waddch(win->x_win, cch);
 168                 } else
 169                         waddch(win->x_win, (unsigned char)*text);
 170                 getyx(win->x_win, win->x_line, win->x_col);
 171                 text++;
 172         }
 173         wrefresh(win->x_win);
 174 }
 175
 176 /*
 177  * Read the character at the indicated position in win
 178  */
 179 int
 180 readwin(WINDOW *win, int line, int col)
 181 {
 182         int oldline, oldcol;
 183         int c;
 184
 185         getyx(win, oldline, oldcol);
 186         wmove(win, line, col);
 187         c = winch(win);
 188         wmove(win, oldline, oldcol);
 189         return (c);
 190 }