xref: /freebsd/usr.bin/talk/display.c (revision eacee0ff7ec955b32e09515246bd97b6edcd2b0f)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 
36 __FBSDID("$FreeBSD$");
37 
38 #ifndef lint
39 static const char sccsid[] = "@(#)display.c	8.1 (Berkeley) 6/6/93";
40 #endif
41 
42 /*
43  * The window 'manager', initializes curses and handles the actual
44  * displaying of text
45  */
46 #include <ctype.h>
47 
48 #include "talk.h"
49 
50 xwin_t	my_win;
51 xwin_t	his_win;
52 WINDOW	*line_win;
53 
54 int	curses_initialized = 0;
55 
56 /*
57  * max HAS to be a function, it is called with
58  * a argument of the form --foo at least once.
59  */
60 int
61 max(a,b)
62 	int a, b;
63 {
64 
65 	return (a > b ? a : b);
66 }
67 
68 /*
69  * Display some text on somebody's window, processing some control
70  * characters while we are at it.
71  */
72 void
73 display(win, text, size)
74 	xwin_t *win;
75 	char *text;
76 	int size;
77 {
78 	int i;
79 	char cch;
80 
81 	for (i = 0; i < size; i++) {
82 		if (*text == '\n' || *text == '\r') {
83 			waddch(win->x_win, '\n');
84 			getyx(win->x_win, win->x_line, win->x_col);
85 			text++;
86 			continue;
87 		}
88 		/* erase character */
89 		if (   *text == win->cerase
90 		    || *text == 010     /* BS */
91 		    || *text == 0177    /* DEL */
92 		   ) {
93 			wmove(win->x_win, win->x_line, max(--win->x_col, 0));
94 			getyx(win->x_win, win->x_line, win->x_col);
95 			waddch(win->x_win, ' ');
96 			wmove(win->x_win, win->x_line, win->x_col);
97 			getyx(win->x_win, win->x_line, win->x_col);
98 			text++;
99 			continue;
100 		}
101 		/*
102 		 * On word erase search backwards until we find
103 		 * the beginning of a word or the beginning of
104 		 * the line.
105 		 */
106 		if (   *text == win->werase
107 		    || *text == 027     /* ^W */
108 		   ) {
109 			int endcol, xcol, ii, c;
110 
111 			endcol = win->x_col;
112 			xcol = endcol - 1;
113 			while (xcol >= 0) {
114 				c = readwin(win->x_win, win->x_line, xcol);
115 				if (c != ' ')
116 					break;
117 				xcol--;
118 			}
119 			while (xcol >= 0) {
120 				c = readwin(win->x_win, win->x_line, xcol);
121 				if (c == ' ')
122 					break;
123 				xcol--;
124 			}
125 			wmove(win->x_win, win->x_line, xcol + 1);
126 			for (ii = xcol + 1; ii < endcol; ii++)
127 				waddch(win->x_win, ' ');
128 			wmove(win->x_win, win->x_line, xcol + 1);
129 			getyx(win->x_win, win->x_line, win->x_col);
130 			text++;
131 			continue;
132 		}
133 		/* line kill */
134 		if (   *text == win->kill
135 		    || *text == 025     /* ^U */
136 		   ) {
137 			wmove(win->x_win, win->x_line, 0);
138 			wclrtoeol(win->x_win);
139 			getyx(win->x_win, win->x_line, win->x_col);
140 			text++;
141 			continue;
142 		}
143 		if (*text == '\f') {
144 			if (win == &my_win)
145 				wrefresh(curscr);
146 			text++;
147 			continue;
148 		}
149 		if (*text == '\7') {
150 			write(STDOUT_FILENO, text, 1);
151 			text++;
152 			continue;
153 		}
154 		if (!isprint((unsigned char)*text) && *text != '\t') {
155 			waddch(win->x_win, '^');
156 			getyx(win->x_win, win->x_line, win->x_col);
157 			cch = (*text & 63) + 64;
158 			waddch(win->x_win, cch);
159 		} else
160 			waddch(win->x_win, (unsigned char)*text);
161 		getyx(win->x_win, win->x_line, win->x_col);
162 		text++;
163 	}
164 	wrefresh(win->x_win);
165 }
166 
167 /*
168  * Read the character at the indicated position in win
169  */
170 int
171 readwin(win, line, col)
172 	WINDOW *win;
173 	int line;
174 	int col;
175 {
176 	int oldline, oldcol;
177 	int c;
178 
179 	getyx(win, oldline, oldcol);
180 	wmove(win, line, col);
181 	c = winch(win);
182 	wmove(win, oldline, oldcol);
183 	return (c);
184 }
185