BSD 4_3_Net_1 release

[unix-history] / talk / display.c

/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
static char sccsid[] = "@(#)display.c   5.3 (Berkeley) 6/29/88";
#endif /* not lint */

/*
* The window 'manager', initializes curses and handles the actual
* displaying of text
*/
#include "talk.h"

xwin_t  my_win;
xwin_t  his_win;
WINDOW  *line_win;

int     curses_initialized = 0;

/*
* max HAS to be a function, it is called with
* a argument of the form --foo at least once.
*/
max(a,b)
       int a, b;
{

       return (a > b ? a : b);
}

/*
* Display some text on somebody's window, processing some control
* characters while we are at it.
*/
display(win, text, size)
       register xwin_t *win;
       register char *text;
       int size;
{
       register int i;
       char cch;

       for (i = 0; i < size; i++) {
               if (*text == '\n') {
                       xscroll(win, 0);
                       text++;
                       continue;
               }
               /* erase character */
               if (*text == win->cerase) {
                       wmove(win->x_win, win->x_line, max(--win->x_col, 0));
                       getyx(win->x_win, win->x_line, win->x_col);
                       waddch(win->x_win, ' ');
                       wmove(win->x_win, win->x_line, win->x_col);
                       getyx(win->x_win, win->x_line, win->x_col);
                       text++;
                       continue;
               }
               /*
                * On word erase search backwards until we find
                * the beginning of a word or the beginning of
                * the line.
                */
               if (*text == win->werase) {
                       int endcol, xcol, i, c;

                       endcol = win->x_col;
                       xcol = endcol - 1;
                       while (xcol >= 0) {
                               c = readwin(win->x_win, win->x_line, xcol);
                               if (c != ' ')
                                       break;
                               xcol--;
                       }
                       while (xcol >= 0) {
                               c = readwin(win->x_win, win->x_line, xcol);
                               if (c == ' ')
                                       break;
                               xcol--;
                       }
                       wmove(win->x_win, win->x_line, xcol + 1);
                       for (i = xcol + 1; i < endcol; i++)
                               waddch(win->x_win, ' ');
                       wmove(win->x_win, win->x_line, xcol + 1);
                       getyx(win->x_win, win->x_line, win->x_col);
                       continue;
               }
               /* line kill */
               if (*text == win->kill) {
                       wmove(win->x_win, win->x_line, 0);
                       wclrtoeol(win->x_win);
                       getyx(win->x_win, win->x_line, win->x_col);
                       text++;
                       continue;
               }
               if (*text == '\f') {
                       if (win == &my_win)
                               wrefresh(curscr);
                       text++;
                       continue;
               }
               if (win->x_col == COLS-1) {
                       /* check for wraparound */
                       xscroll(win, 0);
               }
               if (*text < ' ' && *text != '\t') {
                       waddch(win->x_win, '^');
                       getyx(win->x_win, win->x_line, win->x_col);
                       if (win->x_col == COLS-1) /* check for wraparound */
                               xscroll(win, 0);
                       cch = (*text & 63) + 64;
                       waddch(win->x_win, cch);
               } else
                       waddch(win->x_win, *text);
               getyx(win->x_win, win->x_line, win->x_col);
               text++;
       }
       wrefresh(win->x_win);
}

/*
* Read the character at the indicated position in win
*/
readwin(win, line, col)
       WINDOW *win;
{
       int oldline, oldcol;
       register int c;

       getyx(win, oldline, oldcol);
       wmove(win, line, col);
       c = winch(win);
       wmove(win, oldline, oldcol);
       return (c);
}

/*
* Scroll a window, blanking out the line following the current line
* so that the current position is obvious
*/
xscroll(win, flag)
       register xwin_t *win;
       int flag;
{

       if (flag == -1) {
               wmove(win->x_win, 0, 0);
               win->x_line = 0;
               win->x_col = 0;
               return;
       }
       win->x_line = (win->x_line + 1) % win->x_nlines;
       win->x_col = 0;
       wmove(win->x_win, win->x_line, win->x_col);
       wclrtoeol(win->x_win);
       wmove(win->x_win, (win->x_line + 1) % win->x_nlines, win->x_col);
       wclrtoeol(win->x_win);
       wmove(win->x_win, win->x_line, win->x_col);
}