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