xref: /netbsd-src/bin/sleep/sleep.c (revision d16b7486a53dcb8072b60ec6fcb4373a2d0c27b7)
1 /* $NetBSD: sleep.c,v 1.30 2019/03/10 15:18:45 kre Exp $ */
2 
3 /*
4  * Copyright (c) 1988, 1993, 1994
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 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)sleep.c	8.3 (Berkeley) 4/2/94";
41 #else
42 __RCSID("$NetBSD: sleep.c,v 1.30 2019/03/10 15:18:45 kre Exp $");
43 #endif
44 #endif /* not lint */
45 
46 #include <ctype.h>
47 #include <err.h>
48 #include <errno.h>
49 #include <locale.h>
50 #include <math.h>
51 #include <signal.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <time.h>
56 #include <unistd.h>
57 
58 __dead static void alarmhandle(int);
59 __dead static void usage(void);
60 
61 static void report(const time_t, const time_t, const char *const);
62 
63 static volatile sig_atomic_t report_requested;
64 static void
65 report_request(int signo __unused)
66 {
67 
68 	report_requested = 1;
69 }
70 
71 int
72 main(int argc, char *argv[])
73 {
74 	char *arg, *temp;
75 	const char *msg;
76 	double fval, ival, val;
77 	struct timespec ntime;
78 	struct timespec endtime;
79 	struct timespec now;
80 	time_t original;
81 	int ch, fracflag;
82 
83 	setprogname(argv[0]);
84 	(void)setlocale(LC_ALL, "");
85 
86 	(void)signal(SIGALRM, alarmhandle);
87 
88 	while ((ch = getopt(argc, argv, "")) != -1)
89 		switch(ch) {
90 		default:
91 			usage();
92 		}
93 	argc -= optind;
94 	argv += optind;
95 
96 	if (argc != 1)
97 		usage();
98 
99 	/*
100 	 * Okay, why not just use atof for everything? Why bother
101 	 * checking if there is a fraction in use? Because the old
102 	 * sleep handled the full range of integers, that's why, and a
103 	 * double can't handle a large long. This is fairly useless
104 	 * given how large a number a double can hold on most
105 	 * machines, but now we won't ever have trouble. If you want
106 	 * 1000000000.9 seconds of sleep, well, that's your
107 	 * problem. Why use an isdigit() check instead of checking for
108 	 * a period? Because doing it this way means locales will be
109 	 * handled transparently by the atof code.
110 	 *
111 	 * Since fracflag is set for any non-digit, we also fall
112 	 * into the floating point conversion path if the input
113 	 * is hex (the 'x' in 0xA is not a digit).  Then if
114 	 * strtod() handles hex (on NetBSD it does) so will we.
115 	 * That path is also taken for scientific notation (1.2e+3)
116 	 * and when the input is simply nonsense.
117 	 */
118 	fracflag = 0;
119 	arg = *argv;
120 	for (temp = arg; *temp != '\0'; temp++)
121 		if (!isdigit((unsigned char)*temp)) {
122 			ch = *temp;
123 			fracflag++;
124 		}
125 
126 	if (fracflag) {
127 		/*
128 		 * If we cannot convert the value using the user's locale
129 		 * then try again using the C locale, so strtod() can always
130 		 * parse values like 2.5, even if the user's locale uses
131 		 * a different decimal radix character (like ',')
132 		 *
133 		 * (but only if that is the potential problem)
134 		 */
135 		val = strtod(arg, &temp);
136 		if (*temp != '\0')
137 			val = strtod_l(arg, &temp, LC_C_LOCALE);
138 		if (val < 0 || temp == arg || *temp != '\0')
139 			usage();
140 
141 		ival = floor(val);
142 		fval = (1000000000 * (val-ival));
143 		ntime.tv_sec = ival;
144 		if ((double)ntime.tv_sec != ival)
145 			errx(1, "requested delay (%s) out of range", arg);
146 		ntime.tv_nsec = fval;
147 
148 		if (ntime.tv_sec == 0 && ntime.tv_nsec == 0)
149 			return EXIT_SUCCESS;	/* was 0.0 or underflowed */
150 	} else {
151 		errno = 0;
152 		ntime.tv_sec = strtol(arg, &temp, 10);
153 		if (ntime.tv_sec < 0 || temp == arg || *temp != '\0')
154 			usage();
155 		if (errno == ERANGE)
156 			errx(EXIT_FAILURE, "Requested delay (%s) out of range",
157 			    arg);
158 		else if (errno != 0)
159 			err(EXIT_FAILURE, "Requested delay (%s)", arg);
160 
161 		if (ntime.tv_sec == 0)
162 			return EXIT_SUCCESS;
163 		ntime.tv_nsec = 0;
164 	}
165 
166 	original = ntime.tv_sec;
167 	if (original < 86400) {
168 		if (ntime.tv_nsec > 1000000000 * 2 / 3) {
169 			original++;
170 			msg = " less a bit";
171 		} else if (ntime.tv_nsec != 0)
172 			msg = " and a bit";
173 		else
174 			msg = "";
175 	} else
176 		msg = "";
177 
178 	if (clock_gettime(CLOCK_MONOTONIC, &now) != 0)
179 		err(EXIT_FAILURE, "clock_gettime");
180 	timespecadd(&now, &ntime, &endtime);
181 
182 	if (endtime.tv_sec < now.tv_sec || (endtime.tv_sec == now.tv_sec &&
183 	    endtime.tv_nsec <= now.tv_nsec))
184 		errx(EXIT_FAILURE, "cannot sleep beyond the end of time");
185 
186 	signal(SIGINFO, report_request);
187 	for (;;) {
188 		int e;
189 
190 		if ((e = clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME,
191 		     &endtime, NULL)) == 0)
192 			return EXIT_SUCCESS;
193 
194 		if (!report_requested || e != EINTR) {
195 			errno = e;
196 			err(EXIT_FAILURE, "clock_nanotime");
197 		}
198 
199 		report_requested = 0;
200 		if (clock_gettime(CLOCK_MONOTONIC, &now) != 0) /* Huh? */
201 			continue;
202 
203 		timespecsub(&endtime, &now, &ntime);
204 		report(ntime.tv_sec, original, msg);
205 	}
206 }
207 
208 	/* Reporting does not bother with nanoseconds. */
209 static void
210 report(const time_t remain, const time_t original, const char * const msg)
211 {
212 	if (remain == 0)
213 		warnx("In the final moments of the original"
214 		    " %g%s second%s", (double)original, msg,
215 		    original == 1 && *msg == '\0' ? "" : "s");
216 	else if (remain < 2000)
217 		warnx("Between %jd and %jd seconds left"
218 		    " out of the original %g%s",
219 		    (intmax_t)remain, (intmax_t)remain + 1, (double)original,
220 		    msg);
221 	else if ((original - remain) < 100000 && (original-remain) < original/8)
222 		warnx("Have waited only %jd second%s of the original %g%s",
223 			(intmax_t)(original - remain),
224 			(original - remain) == 1 ? "" : "s",
225 			(double)original, msg);
226 	else
227 		warnx("Approximately %g seconds left out of the original %g%s",
228 			(double)remain, (double)original, msg);
229 }
230 
231 static void
232 usage(void)
233 {
234 	(void)fprintf(stderr, "usage: %s seconds\n", getprogname());
235 	exit(EXIT_FAILURE);
236 	/* NOTREACHED */
237 }
238 
239 /* ARGSUSED */
240 static void
241 alarmhandle(int i)
242 {
243 	_exit(EXIT_SUCCESS);
244 	/* NOTREACHED */
245 }
246