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      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