1/*	$OpenBSD: display.c,v 1.18 2016/02/01 07:29:25 mestre Exp $	*/
2/*	$NetBSD: display.c,v 1.3 1994/12/09 02:14:13 jtc Exp $	*/
3
4/*
5 * Copyright (c) 1983, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * The window 'manager', initializes curses and handles the actual
35 * displaying of text
36 */
37#include <ctype.h>
38
39#include "talk.h"
40
41xwin_t	my_win;
42xwin_t	his_win;
43WINDOW	*line_win;
44
45int	curses_initialized;
46int	high_print;
47bool	smooth_scroll;
48
49/*
50 * max HAS to be a function, it is called with
51 * an argument of the form --foo at least once.
52 */
53int
54max(int a, int b)
55{
56
57	return (a > b ? a : b);
58}
59
60/*
61 * Display some text on somebody's window, processing some control
62 * characters while we are at it.
63 */
64void
65display(xwin_t *win, char *text, int size)
66{
67	int i;
68	char cch;
69
70	for (i = 0; i < size; i++) {
71		/*
72		 * Since we do not use curses's input routines we must
73		 * convert '\r' -> '\n' ourselves.
74		 */
75		if (*text == '\r')
76			*text = '\n';
77		if (*text == '\n') {
78			xscroll(win, 0);
79			text++;
80			continue;
81		}
82		/* erase character */
83		if (*text == win->cerase) {
84			wmove(win->x_win, win->x_line, max(--win->x_col, 0));
85			getyx(win->x_win, win->x_line, win->x_col);
86			waddch(win->x_win, ' ');
87			wmove(win->x_win, win->x_line, win->x_col);
88			getyx(win->x_win, win->x_line, win->x_col);
89			text++;
90			continue;
91		}
92		/*
93		 * On word erase search backwards until we find
94		 * the beginning of a word or the beginning of
95		 * the line.
96		 */
97		if (*text == win->werase) {
98			int endcol, xcol, i, c;
99
100			endcol = win->x_col;
101			xcol = endcol - 1;
102			while (xcol >= 0) {
103				c = readwin(win->x_win, win->x_line, xcol);
104				if (c != ' ')
105					break;
106				xcol--;
107			}
108			while (xcol >= 0) {
109				c = readwin(win->x_win, win->x_line, xcol);
110				if (c == ' ')
111					break;
112				xcol--;
113			}
114			wmove(win->x_win, win->x_line, xcol + 1);
115			for (i = xcol + 1; i < endcol; i++)
116				waddch(win->x_win, ' ');
117			wmove(win->x_win, win->x_line, xcol + 1);
118			getyx(win->x_win, win->x_line, win->x_col);
119			text++;
120			continue;
121		}
122		/* line kill */
123		if (*text == win->kill) {
124			wmove(win->x_win, win->x_line, 0);
125			wclrtoeol(win->x_win);
126			getyx(win->x_win, win->x_line, win->x_col);
127			text++;
128			continue;
129		}
130		if (*text == '\f') {
131			if (win == &my_win)
132				wrefresh(curscr);
133			text++;
134			continue;
135		}
136		if (win->x_col == COLS-1) {
137			/* check for wraparound */
138			xscroll(win, 0);
139		}
140		if (*text != '\t' &&
141		    ((!high_print && !isprint((unsigned char)*text)) ||
142		      iscntrl((unsigned char)*text))) {
143			waddch(win->x_win, '^');
144			getyx(win->x_win, win->x_line, win->x_col);
145			if (win->x_col == COLS-1) /* check for wraparound */
146				xscroll(win, 0);
147			cch = (*text & 63) + 64;
148			waddch(win->x_win, cch);
149		} else
150			waddch(win->x_win, (unsigned char)(*text));
151		getyx(win->x_win, win->x_line, win->x_col);
152		text++;
153	}
154	wrefresh(win->x_win);
155}
156
157/*
158 * Read the character at the indicated position in win
159 */
160int
161readwin(WINDOW *win, int line, int col)
162{
163	int oldline, oldcol;
164	int c;
165
166	getyx(win, oldline, oldcol);
167	wmove(win, line, col);
168	c = winch(win);
169	wmove(win, oldline, oldcol);
170	return (c);
171}
172
173/*
174 * Scroll a window, blanking out the line following the current line
175 * so that the current position is obvious
176 */
177void
178xscroll(xwin_t *win, int flag)
179{
180
181	if (flag == -1) {
182		wmove(win->x_win, 0, 0);
183		win->x_line = 0;
184		win->x_col = 0;
185		return;
186	}
187	win->x_col = 0;
188	if (smooth_scroll) {
189		if (++win->x_line == win->x_nlines) {
190			--win->x_line;
191			scroll(win->x_win);
192		}
193	} else {
194		win->x_line = (win->x_line + 1) % win->x_nlines;
195		wmove(win->x_win, win->x_line, win->x_col);
196		wclrtoeol(win->x_win);
197		wmove(win->x_win, (win->x_line + 1) % win->x_nlines,
198		    win->x_col);
199		wclrtoeol(win->x_win);
200	}
201	wmove(win->x_win, win->x_line, win->x_col);
202}
203