xref: /dragonfly/usr.bin/talk/display.c (revision d8082429)
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. 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  * @(#)display.c	8.1 (Berkeley) 6/6/93
30  * $FreeBSD: src/usr.bin/talk/display.c,v 1.7 1999/08/28 01:06:11 peter Exp $
31  * $DragonFly: src/usr.bin/talk/display.c,v 1.4 2003/10/04 20:36:52 hmp Exp $
32  */
33 
34 /*
35  * The window 'manager', initializes curses and handles the actual
36  * displaying of text
37  */
38 #include "talk.h"
39 #include <ctype.h>
40 
41 xwin_t	my_win;
42 xwin_t	his_win;
43 WINDOW	*line_win;
44 
45 int	curses_initialized = 0;
46 
47 /*
48  * max HAS to be a function, it is called with
49  * an argument of the form --foo at least once.
50  */
51 int
52 max(int a, int b)
53 {
54 
55 	return (a > b ? a : b);
56 }
57 
58 /*
59  * Display some text on somebody's window, processing some control
60  * characters while we are at it.
61  */
62 void
63 display(xwin_t *win, char *text, int size)
64 {
65 	int i;
66 	char cch;
67 
68 	for (i = 0; i < size; i++) {
69 		if (*text == '\n' || *text == '\r') {
70 			waddch(win->x_win, '\n');
71 			getyx(win->x_win, win->x_line, win->x_col);
72 			text++;
73 			continue;
74 		}
75 		if (*text == 004 && win == &my_win) {
76 			/* control-D clears the screen */
77 			werase(my_win.x_win);
78 			getyx(my_win.x_win, my_win.x_line, my_win.x_col);
79 			wrefresh(my_win.x_win);
80 			werase(his_win.x_win);
81 			getyx(his_win.x_win, his_win.x_line, his_win.x_col);
82 			wrefresh(his_win.x_win);
83 			text++;
84 			continue;
85 		}
86 
87 		/* erase character */
88 		if (   *text == win->cerase
89 		    || *text == 010     /* BS */
90 		    || *text == 0177    /* DEL */
91 		   ) {
92 			wmove(win->x_win, win->x_line, max(--win->x_col, 0));
93 			getyx(win->x_win, win->x_line, win->x_col);
94 			waddch(win->x_win, ' ');
95 			wmove(win->x_win, win->x_line, win->x_col);
96 			getyx(win->x_win, win->x_line, win->x_col);
97 			text++;
98 			continue;
99 		}
100 		/*
101 		 * On word erase search backwards until we find
102 		 * the beginning of a word or the beginning of
103 		 * the line.
104 		 */
105 		if (   *text == win->werase
106 		    || *text == 027     /* ^W */
107 		   ) {
108 			int endcol, xcol, ii, c;
109 
110 			endcol = win->x_col;
111 			xcol = endcol - 1;
112 			while (xcol >= 0) {
113 				c = readwin(win->x_win, win->x_line, xcol);
114 				if (c != ' ')
115 					break;
116 				xcol--;
117 			}
118 			while (xcol >= 0) {
119 				c = readwin(win->x_win, win->x_line, xcol);
120 				if (c == ' ')
121 					break;
122 				xcol--;
123 			}
124 			wmove(win->x_win, win->x_line, xcol + 1);
125 			for (ii = xcol + 1; ii < endcol; ii++)
126 				waddch(win->x_win, ' ');
127 			wmove(win->x_win, win->x_line, xcol + 1);
128 			getyx(win->x_win, win->x_line, win->x_col);
129 			text++;
130 			continue;
131 		}
132 		/* line kill */
133 		if (   *text == win->kill
134 		    || *text == 025     /* ^U */
135 		   ) {
136 			wmove(win->x_win, win->x_line, 0);
137 			wclrtoeol(win->x_win);
138 			getyx(win->x_win, win->x_line, win->x_col);
139 			text++;
140 			continue;
141 		}
142 		if (*text == '\f') {
143 			if (win == &my_win)
144 				wrefresh(curscr);
145 			text++;
146 			continue;
147 		}
148 		if (*text == '\7') {
149 			write(STDOUT_FILENO, text, 1);
150 			text++;
151 			continue;
152 		}
153 		if (!isprint((unsigned char)*text) && *text != '\t') {
154 			waddch(win->x_win, '^');
155 			getyx(win->x_win, win->x_line, win->x_col);
156 			cch = (*text & 63) + 64;
157 			waddch(win->x_win, cch);
158 		} else
159 			waddch(win->x_win, (unsigned char)*text);
160 		getyx(win->x_win, win->x_line, win->x_col);
161 		text++;
162 	}
163 	wrefresh(win->x_win);
164 }
165 
166 /*
167  * Read the character at the indicated position in win
168  */
169 int
170 readwin(WINDOW *win, int line, int col)
171 {
172 	int oldline, oldcol;
173 	int c;
174 
175 	getyx(win, oldline, oldcol);
176 	wmove(win, line, col);
177 	c = winch(win);
178 	wmove(win, oldline, oldcol);
179 	return (c);
180 }
181