xref: /netbsd-src/external/bsd/file/dist/src/cdf_time.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: cdf_time.c,v 1.6 2014/06/13 02:08:06 christos Exp $	*/
2 /*-
3  * Copyright (c) 2008 Christos Zoulas
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
19  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "file.h"
29 
30 #ifndef lint
31 #if 0
32 FILE_RCSID("@(#)$File: cdf_time.c,v 1.15 2014/05/14 23:15:42 christos Exp $")
33 #else
34 __RCSID("$NetBSD: cdf_time.c,v 1.6 2014/06/13 02:08:06 christos Exp $");
35 #endif
36 #endif
37 
38 #include <time.h>
39 #ifdef TEST
40 #include <err.h>
41 #endif
42 #include <string.h>
43 
44 #include "cdf.h"
45 
46 #define isleap(y) ((((y) % 4) == 0) && \
47     ((((y) % 100) != 0) || (((y) % 400) == 0)))
48 
49 static const int mdays[] = {
50     31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
51 };
52 
53 /*
54  * Return the number of days between jan 01 1601 and jan 01 of year.
55  */
56 static int
57 cdf_getdays(int year)
58 {
59 	int days = 0;
60 	int y;
61 
62 	for (y = CDF_BASE_YEAR; y < year; y++)
63 		days += isleap(y) + 365;
64 
65 	return days;
66 }
67 
68 /*
69  * Return the day within the month
70  */
71 static int
72 cdf_getday(int year, int days)
73 {
74 	size_t m;
75 
76 	for (m = 0; m < sizeof(mdays) / sizeof(mdays[0]); m++) {
77 		int sub = mdays[m] + (m == 1 && isleap(year));
78 		if (days < sub)
79 			return days;
80 		days -= sub;
81 	}
82 	return days;
83 }
84 
85 /*
86  * Return the 0...11 month number.
87  */
88 static int
89 cdf_getmonth(int year, int days)
90 {
91 	size_t m;
92 
93 	for (m = 0; m < sizeof(mdays) / sizeof(mdays[0]); m++) {
94 		days -= mdays[m];
95 		if (m == 1 && isleap(year))
96 			days--;
97 		if (days <= 0)
98 			return (int)m;
99 	}
100 	return (int)m;
101 }
102 
103 int
104 cdf_timestamp_to_timespec(struct timespec *ts, cdf_timestamp_t t)
105 {
106 	struct tm tm;
107 #ifdef HAVE_STRUCT_TM_TM_ZONE
108 	static char UTC[] = "UTC";
109 #endif
110 	int rdays;
111 
112 	/* Unit is 100's of nanoseconds */
113 	ts->tv_nsec = (t % CDF_TIME_PREC) * 100;
114 
115 	t /= CDF_TIME_PREC;
116 	tm.tm_sec = (int)(t % 60);
117 	t /= 60;
118 
119 	tm.tm_min = (int)(t % 60);
120 	t /= 60;
121 
122 	tm.tm_hour = (int)(t % 24);
123 	t /= 24;
124 
125 	/* XXX: Approx */
126 	tm.tm_year = (int)(CDF_BASE_YEAR + (t / 365));
127 
128 	rdays = cdf_getdays(tm.tm_year);
129 	t -= rdays - 1;
130 	tm.tm_mday = cdf_getday(tm.tm_year, (int)t);
131 	tm.tm_mon = cdf_getmonth(tm.tm_year, (int)t);
132 	tm.tm_wday = 0;
133 	tm.tm_yday = 0;
134 	tm.tm_isdst = 0;
135 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
136 	tm.tm_gmtoff = 0;
137 #endif
138 #ifdef HAVE_STRUCT_TM_TM_ZONE
139 	tm.tm_zone = UTC;
140 #endif
141 	tm.tm_year -= 1900;
142 	ts->tv_sec = mktime(&tm);
143 	if (ts->tv_sec == -1) {
144 		errno = EINVAL;
145 		return -1;
146 	}
147 	return 0;
148 }
149 
150 int
151 /*ARGSUSED*/
152 cdf_timespec_to_timestamp(cdf_timestamp_t *t, const struct timespec *ts)
153 {
154 #ifndef __lint__
155 	(void)&t;
156 	(void)&ts;
157 #endif
158 #ifdef notyet
159 	struct tm tm;
160 	if (gmtime_r(&ts->ts_sec, &tm) == NULL) {
161 		errno = EINVAL;
162 		return -1;
163 	}
164 	*t = (ts->ts_nsec / 100) * CDF_TIME_PREC;
165 	*t = tm.tm_sec;
166 	*t += tm.tm_min * 60;
167 	*t += tm.tm_hour * 60 * 60;
168 	*t += tm.tm_mday * 60 * 60 * 24;
169 #endif
170 	return 0;
171 }
172 
173 char *
174 cdf_ctime(const time_t *sec, char *buf)
175 {
176 	char *ptr = ctime_r(sec, buf);
177 	if (ptr != NULL)
178 		return buf;
179 	(void)snprintf(buf, 26, "*Bad* 0x%16.16" INT64_T_FORMAT "x\n",
180 	    (long long)*sec);
181 	return buf;
182 }
183 
184 
185 #ifdef TEST_TIME
186 int
187 main(int argc, char *argv[])
188 {
189 	struct timespec ts;
190 	char buf[25];
191 	static const cdf_timestamp_t tst = 0x01A5E403C2D59C00ULL;
192 	static const char *ref = "Sat Apr 23 01:30:00 1977";
193 	char *p, *q;
194 
195 	cdf_timestamp_to_timespec(&ts, tst);
196 	p = cdf_ctime(&ts.tv_sec, buf);
197 	if ((q = strchr(p, '\n')) != NULL)
198 		*q = '\0';
199 	if (strcmp(ref, p) != 0)
200 		errx(1, "Error date %s != %s\n", ref, p);
201 	return 0;
202 }
203 #endif
204