/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 * 4. 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
 30#include <sys/cdefs.h>
 31
 32__FBSDID("$FreeBSD$");
 33
 34#ifndef lint
 35static const char sccsid[] = "@(#)display.c	8.1 (Berkeley) 6/6/93";
 36#endif
 37
 38/*
 39 * The window 'manager', initializes curses and handles the actual
 40 * displaying of text
 41 */
 42#include <ctype.h>
 43#include <unistd.h>
 44
 45#include "talk.h"
 46
 47xwin_t	my_win;
 48xwin_t	his_win;
 49WINDOW	*line_win;
 50
 51int	curses_initialized = 0;
 52
 53/*
 54 * max HAS to be a function, it is called with
 55 * an argument of the form --foo at least once.
 56 */
 57int
 58max(int a, int b)
 59{
 60
 61	return (a > b ? a : b);
 62}
 63
 64/*
 65 * Display some text on somebody's window, processing some control
 66 * characters while we are at it.
 67 */
 68void
 69display(xwin_t *win, char *text, int size)
 70{
 71	int i;
 72	char cch;
 73
 74	for (i = 0; i < size; i++) {
 75		if (*text == '\n' || *text == '\r') {
 76			waddch(win->x_win, '\n');
 77			getyx(win->x_win, win->x_line, win->x_col);
 78			text++;
 79			continue;
 80		}
 81		if (*text == 004 && win == &my_win) {
 82			/* control-D clears the screen */
 83			werase(my_win.x_win);
 84			getyx(my_win.x_win, my_win.x_line, my_win.x_col);
 85			wrefresh(my_win.x_win);
 86			werase(his_win.x_win);
 87			getyx(his_win.x_win, his_win.x_line, his_win.x_col);
 88			wrefresh(his_win.x_win);
 89			text++;
 90			continue;
 91		}
 92
 93		/* erase character */
 94		if (   *text == win->cerase
 95		    || *text == 010     /* BS */
 96		    || *text == 0177    /* DEL */
 97		   ) {
 98			wmove(win->x_win, win->x_line, max(--win->x_col, 0));
 99			getyx(win->x_win, win->x_line, win->x_col);
100			waddch(win->x_win, ' ');
101			wmove(win->x_win, win->x_line, win->x_col);
102			getyx(win->x_win, win->x_line, win->x_col);
103			text++;
104			continue;
105		}
106		/*
107		 * On word erase search backwards until we find
108		 * the beginning of a word or the beginning of
109		 * the line.
110		 */
111		if (   *text == win->werase
112		    || *text == 027     /* ^W */
113		   ) {
114			int endcol, xcol, ii, c;
115
116			endcol = win->x_col;
117			xcol = endcol - 1;
118			while (xcol >= 0) {
119				c = readwin(win->x_win, win->x_line, xcol);
120				if (c != ' ')
121					break;
122				xcol--;
123			}
124			while (xcol >= 0) {
125				c = readwin(win->x_win, win->x_line, xcol);
126				if (c == ' ')
127					break;
128				xcol--;
129			}
130			wmove(win->x_win, win->x_line, xcol + 1);
131			for (ii = xcol + 1; ii < endcol; ii++)
132				waddch(win->x_win, ' ');
133			wmove(win->x_win, win->x_line, xcol + 1);
134			getyx(win->x_win, win->x_line, win->x_col);
135			text++;
136			continue;
137		}
138		/* line kill */
139		if (   *text == win->kill
140		    || *text == 025     /* ^U */
141		   ) {
142			wmove(win->x_win, win->x_line, 0);
143			wclrtoeol(win->x_win);
144			getyx(win->x_win, win->x_line, win->x_col);
145			text++;
146			continue;
147		}
148		if (*text == '\f') {
149			if (win == &my_win)
150				wrefresh(curscr);
151			text++;
152			continue;
153		}
154		if (*text == '\7') {
155			write(STDOUT_FILENO, text, 1);
156			text++;
157			continue;
158		}
159		if (!isprint((unsigned char)*text) && *text != '\t') {
160			waddch(win->x_win, '^');
161			getyx(win->x_win, win->x_line, win->x_col);
162			cch = (*text & 63) + 64;
163			waddch(win->x_win, cch);
164		} else
165			waddch(win->x_win, (unsigned char)*text);
166		getyx(win->x_win, win->x_line, win->x_col);
167		text++;
168	}
169	wrefresh(win->x_win);
170}
171
172/*
173 * Read the character at the indicated position in win
174 */
175int
176readwin(WINDOW *win, int line, int col)
177{
178	int oldline, oldcol;
179	int c;
180
181	getyx(win, oldline, oldcol);
182	wmove(win, line, col);
183	c = winch(win);
184	wmove(win, oldline, oldcol);
185	return (c);
186}