1 /* $NetBSD: ns_date.c,v 1.2 2018/12/13 08:39:34 maya Exp $ */
2
3 /*
4 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (c) 1999 by Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
17 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 #include <sys/cdefs.h>
21 #if 0
22 static const char rcsid[] = "Id: ns_date.c,v 1.6 2005/04/27 04:56:39 sra Exp ";
23 #else
24 __RCSID("$NetBSD: ns_date.c,v 1.2 2018/12/13 08:39:34 maya Exp $");
25 #endif
26
27 /* Import. */
28
29 #include "port_before.h"
30
31 #include <arpa/nameser.h>
32
33 #include <ctype.h>
34 #include <errno.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <time.h>
38
39 #include "port_after.h"
40
41 /* Forward. */
42
43 static int datepart(const char *, int, int, int, int *);
44
45 /* Public. */
46
47 /*%
48 * Convert a date in ASCII into the number of seconds since
49 * 1 January 1970 (GMT assumed). Format is yyyymmddhhmmss, all
50 * digits required, no spaces allowed.
51 */
52
53 u_int32_t
ns_datetosecs(const char * cp,int * errp)54 ns_datetosecs(const char *cp, int *errp) {
55 struct tm tim;
56 u_int32_t result;
57 int mdays, i;
58 static const int days_per_month[12] =
59 {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
60
61 if (strlen(cp) != 14U) {
62 *errp = 1;
63 return (0);
64 }
65 *errp = 0;
66
67 memset(&tim, 0, sizeof tim);
68 tim.tm_year = datepart(cp + 0, 4, 1990, 9999, errp) - 1900;
69 tim.tm_mon = datepart(cp + 4, 2, 01, 12, errp) - 1;
70 tim.tm_mday = datepart(cp + 6, 2, 01, 31, errp);
71 tim.tm_hour = datepart(cp + 8, 2, 00, 23, errp);
72 tim.tm_min = datepart(cp + 10, 2, 00, 59, errp);
73 tim.tm_sec = datepart(cp + 12, 2, 00, 59, errp);
74 if (*errp) /*%< Any parse errors? */
75 return (0);
76
77 /*
78 * OK, now because timegm() is not available in all environments,
79 * we will do it by hand. Roll up sleeves, curse the gods, begin!
80 */
81
82 #define SECS_PER_DAY ((u_int32_t)24*60*60)
83 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
84
85 result = tim.tm_sec; /*%< Seconds */
86 result += tim.tm_min * 60; /*%< Minutes */
87 result += tim.tm_hour * (60*60); /*%< Hours */
88 result += (tim.tm_mday - 1) * SECS_PER_DAY; /*%< Days */
89 /* Months are trickier. Look without leaping, then leap */
90 mdays = 0;
91 for (i = 0; i < tim.tm_mon; i++)
92 mdays += days_per_month[i];
93 result += mdays * SECS_PER_DAY; /*%< Months */
94 if (tim.tm_mon > 1 && isleap(1900+tim.tm_year))
95 result += SECS_PER_DAY; /*%< Add leapday for this year */
96 /* First figure years without leapdays, then add them in. */
97 /* The loop is slow, FIXME, but simple and accurate. */
98 result += (tim.tm_year - 70) * (SECS_PER_DAY*365); /*%< Years */
99 for (i = 70; i < tim.tm_year; i++)
100 if (isleap(1900+i))
101 result += SECS_PER_DAY; /*%< Add leapday for prev year */
102 return (result);
103 }
104
105 /* Private. */
106
107 /*%
108 * Parse part of a date. Set error flag if any error.
109 * Don't reset the flag if there is no error.
110 */
111 static int
datepart(const char * buf,int size,int min,int max,int * errp)112 datepart(const char *buf, int size, int min, int max, int *errp) {
113 int result = 0;
114 int i;
115
116 for (i = 0; i < size; i++) {
117 if (!isdigit((unsigned char)(buf[i])))
118 *errp = 1;
119 result = (result * 10) + buf[i] - '0';
120 }
121 if (result < min)
122 *errp = 1;
123 if (result > max)
124 *errp = 1;
125 return (result);
126 }
127
128 /*! \file */
129