xref: /freebsd/usr.bin/systat/keyboard.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 
33 
34 #include <sys/select.h>
35 #include <sys/time.h>
36 
37 #include <errno.h>
38 #include <ctype.h>
39 #include <stdlib.h>
40 #include <termios.h>
41 #include <unistd.h>
42 
43 #include "systat.h"
44 #include "extern.h"
45 
46 static char line[80];
47 static int keyboard_dispatch(int ch);
48 
49 int
50 keyboard(void)
51 {
52 	int ch, n;
53 	struct timeval last, intvl, now, tm;
54 	fd_set rfds;
55 
56 	/* Set initial timings */
57 	gettimeofday(&last, NULL);
58 	intvl.tv_sec = delay / 1000000;
59 	intvl.tv_usec = delay % 1000000;
60 	for (;;) {
61 		col = 0;
62 		move(CMDLINE, 0);
63 		for (;;) {
64 			/* Determine interval to sleep */
65 			(void)gettimeofday(&now, NULL);
66 			tm.tv_sec = last.tv_sec + intvl.tv_sec - now.tv_sec;
67 			tm.tv_usec = last.tv_usec + intvl.tv_usec - now.tv_usec;
68 			while (tm.tv_usec < 0) {
69 				tm.tv_usec += 1000000;
70 				tm.tv_sec--;
71 			}
72 			while (tm.tv_usec >= 1000000) {
73 				tm.tv_usec -= 1000000;
74 				tm.tv_sec++;
75 			}
76 			if (tm.tv_sec < 0) {
77 				/* We have to update screen immediately */
78 				display();
79 				gettimeofday(&last, NULL);
80 				continue;
81 			}
82 
83 			/* Prepare select  */
84 			FD_ZERO(&rfds);
85 			FD_SET(STDIN_FILENO, &rfds);
86 			n = select(STDIN_FILENO + 1, &rfds, NULL, NULL, &tm);
87 
88 			if (n > 0) {
89 				/* Read event on stdin */
90 				ch = getch();
91 
92 				if (keyboard_dispatch(ch) == 0) {
93 					refresh();
94 					continue;
95 				}
96 
97 				line[col] = '\0';
98 				command(line + 1);
99 				/* Refresh delay */
100 				intvl.tv_sec = delay / 1000000;
101 				intvl.tv_usec = delay % 1000000;
102 				refresh();
103 				break;
104 			}
105 
106 			if (n < 0 && errno != EINTR)
107 				exit(1);
108 
109 			/* Timeout or signal. Call display another time */
110 			display();
111 			gettimeofday(&last, NULL);
112 		}
113 	}
114 }
115 
116 static int
117 keyboard_dispatch(int ch)
118 {
119 
120 	if (ch == ERR) {
121 		if (errno == EINTR)
122 			return 0;
123 		exit(1);
124 	}
125 	if (ch >= 'A' && ch <= 'Z')
126 		ch += 'a' - 'A';
127 	if (col == 0) {
128 		if (ch == CTRL('l')) {
129 			wrefresh(curscr);
130 			return 0;
131 		}
132 		if (ch == CTRL('g')) {
133 			status();
134 			return 0;
135 		}
136 		if (ch != ':')
137 			return 0;
138 		move(CMDLINE, 0);
139 		clrtoeol();
140 	}
141 	if (ch == erasechar() && col > 0) {
142 		if (col == 1 && line[0] == ':')
143 			return 0;
144 		col--;
145 		goto doerase;
146 	}
147 	if (ch == CTRL('w') && col > 0) {
148 		while (--col >= 0 && isspace(line[col]))
149 			;
150 		col++;
151 		while (--col >= 0 && !isspace(line[col]))
152 			if (col == 0 && line[0] == ':')
153 				return 1;
154 		col++;
155 		goto doerase;
156 	}
157 	if (ch == killchar() && col > 0) {
158 		col = 0;
159 		if (line[0] == ':')
160 			col++;
161 doerase:
162 		move(CMDLINE, col);
163 		clrtoeol();
164 		return 0;
165 	}
166 	if (isprint(ch) || ch == ' ') {
167 		line[col] = ch;
168 		mvaddch(CMDLINE, col, ch);
169 		col++;
170 	}
171 
172 	if (col == 0 || (ch != '\r' && ch != '\n'))
173 		return 0;
174 
175 	return 1;
176 }
177