summaryrefslogtreecommitdiff
path: root/usr.bin/talk/display.c
blob: 6b080952e81dd6f876bda2c7eb9e87611e10a4c6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
/*	$OpenBSD: display.c,v 1.17 2013/11/28 18:24:55 deraadt Exp $	*/
/*	$NetBSD: display.c,v 1.3 1994/12/09 02:14:13 jtc Exp $	*/

/*
 * Copyright (c) 1983, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

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

xwin_t	my_win;
xwin_t	his_win;
WINDOW	*line_win;

int	curses_initialized;
int	high_print;
bool	smooth_scroll;

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

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

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

	for (i = 0; i < size; i++) {
		/*
		 * Since we do not use curses's input routines we must
		 * convert '\r' -> '\n' ourselves.
		 */
		if (*text == '\r')
			*text = '\n';
		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);
			text++;
			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 != '\t' &&
		    ((!high_print && !isprint((unsigned char)*text)) ||
		      iscntrl((unsigned char)*text))) {
			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, (unsigned char)(*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
 */
int
readwin(WINDOW *win, int line, int col)
{
	int oldline, oldcol;
	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
 */
void
xscroll(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_col = 0;
	if (smooth_scroll) {
		if (++win->x_line == win->x_nlines) {
			--win->x_line;
			scroll(win->x_win);
		}
	} else {
		win->x_line = (win->x_line + 1) % win->x_nlines;
		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);
}