xref: /original-bsd/bin/date/date.c (revision 3f14a87d)
1 /*
2  * Copyright (c) 1985, 1987, 1988 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 char copyright[] =
10 "@(#) Copyright (c) 1985, 1987, 1988 The Regents of the University of California.\n\
11  All rights reserved.\n";
12 #endif /* not lint */
13 
14 #ifndef lint
15 static char sccsid[] = "@(#)date.c	5.9 (Berkeley) 04/28/93";
16 #endif /* not lint */
17 
18 #include <sys/param.h>
19 #include <sys/time.h>
20 
21 #include <ctype.h>
22 #include <err.h>
23 #include <fcntl.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <syslog.h>
28 #include <unistd.h>
29 
30 #include "extern.h"
31 
32 time_t tval;
33 int retval, nflag;
34 
35 static void setthetime __P((char *));
36 static void badformat __P((void));
37 static void usage __P((void));
38 
39 int logwtmp __P((char *, char *, char *));
40 
41 int
42 main(argc, argv)
43 	int argc;
44 	char **argv;
45 {
46 	extern int optind;
47 	extern char *optarg;
48 	struct timezone tz;
49 	int ch, rflag;
50 	char *format, buf[1024];
51 
52 	tz.tz_dsttime = tz.tz_minuteswest = 0;
53 	rflag = 0;
54 	while ((ch = getopt(argc, argv, "d:nr:ut:")) != EOF)
55 		switch((char)ch) {
56 		case 'd':		/* daylight savings time */
57 			tz.tz_dsttime = atoi(optarg) ? 1 : 0;
58 			break;
59 		case 'n':		/* don't set network */
60 			nflag = 1;
61 			break;
62 		case 'r':		/* user specified seconds */
63 			rflag = 1;
64 			tval = atol(optarg);
65 			break;
66 		case 'u':		/* do everything in GMT */
67 			(void)setenv("TZ", "GMT0", 1);
68 			break;
69 		case 't':		/* minutes west of GMT */
70 					/* error check; don't allow "PST" */
71 			if (isdigit(*optarg)) {
72 				tz.tz_minuteswest = atoi(optarg);
73 				break;
74 			}
75 			/* FALLTHROUGH */
76 		default:
77 			usage();
78 		}
79 	argc -= optind;
80 	argv += optind;
81 
82 	/*
83 	 * If -d or -t, set the timezone or daylight savings time; this
84 	 * doesn't belong here, there kernel should not know about either.
85 	 */
86 	if ((tz.tz_minuteswest || tz.tz_dsttime) &&
87 	    settimeofday(NULL, &tz))
88 		err(1, "settimeofday");
89 
90 	if (!rflag && time(&tval) == -1)
91 		err(1, "time");
92 
93 	format = "%a %b %e %H:%M:%S %Z %Y\n";
94 
95 	/* allow the operands in any order */
96 	if (*argv && **argv == '+') {
97 		format = *argv + 1;
98 		++argv;
99 	}
100 
101 	if (*argv) {
102 		setthetime(*argv);
103 		++argv;
104 	}
105 
106 	if (*argv && **argv == '+')
107 		format = *argv + 1;
108 
109 	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
110 	(void)printf("%s", buf);
111 	exit(retval);
112 }
113 
114 #define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
115 void
116 setthetime(p)
117 	register char *p;
118 {
119 	register struct tm *lt;
120 	struct timeval tv;
121 	char *dot, *t;
122 
123 	for (t = p, dot = NULL; *t; ++t) {
124 		if (isdigit(*t))
125 			continue;
126 		if (*t == '.' && dot == NULL) {
127 			dot = t;
128 			continue;
129 		}
130 		badformat();
131 	}
132 
133 	lt = localtime(&tval);
134 
135 	if (dot != NULL) {			/* .ss */
136 		*dot++ = '\0';
137 		if (strlen(dot) != 2)
138 			badformat();
139 		lt->tm_sec = ATOI2(dot);
140 		if (lt->tm_sec > 61)
141 			badformat();
142 	} else
143 		lt->tm_sec = 0;
144 
145 	switch (strlen(p)) {
146 	case 10:				/* yy */
147 		lt->tm_year = ATOI2(p);
148 		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
149 			lt->tm_year += 100;
150 		/* FALLTHROUGH */
151 	case 8:					/* mm */
152 		lt->tm_mon = ATOI2(p);
153 		if (lt->tm_mon > 12)
154 			badformat();
155 		--lt->tm_mon;			/* time struct is 0 - 11 */
156 		/* FALLTHROUGH */
157 	case 6:					/* dd */
158 		lt->tm_mday = ATOI2(p);
159 		if (lt->tm_mday > 31)
160 			badformat();
161 		/* FALLTHROUGH */
162 	case 4:					/* hh */
163 		lt->tm_hour = ATOI2(p);
164 		if (lt->tm_hour > 23)
165 			badformat();
166 		/* FALLTHROUGH */
167 	case 2:					/* mm */
168 		lt->tm_min = ATOI2(p);
169 		if (lt->tm_min > 59)
170 			badformat();
171 		break;
172 	default:
173 		badformat();
174 	}
175 
176 	/* convert broken-down time to GMT clock time */
177 	if ((tval = mktime(lt)) == -1)
178 		badformat();
179 
180 	/* set the time */
181 	if (nflag || netsettime(tval)) {
182 		logwtmp("|", "date", "");
183 		tv.tv_sec = tval;
184 		tv.tv_usec = 0;
185 		if (settimeofday(&tv, NULL)) {
186 			perror("date: settimeofday");
187 			exit(1);
188 		}
189 		logwtmp("{", "date", "");
190 	}
191 
192 	if ((p = getlogin()) == NULL)
193 		p = "???";
194 	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
195 }
196 
197 static void
198 badformat()
199 {
200 	warnx("illegal time format");
201 	usage();
202 }
203 
204 static void
205 usage()
206 {
207 	(void)fprintf(stderr,
208 	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
209 	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
210 	exit(1);
211 }
212