1/*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/* Import. */
19
20#include <arpa/nameser.h>
21
22#include <ctype.h>
23#include <errno.h>
24#include <stdio.h>
25#include <string.h>
26#include <time.h>
27
28#define SPRINTF(x) ((size_t)sprintf x)
29
30/* Forward. */
31
32static int datepart(const char *, int, int, int, int *);
33
34/* Public. */
35
36/*%
37 * Convert a date in ASCII into the number of seconds since
38 * 1 January 1970 (GMT assumed). Format is yyyymmddhhmmss, all
39 * digits required, no spaces allowed.
40 */
41
42uint32_t
43ns_datetosecs(const char *cp, int *errp) {
44 struct tm time;
45 uint32_t result;
46 int mdays, i;
47 static const int days_per_month[12] =
48 {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
49
50 if (strlen(s: cp) != 14U) {
51 *errp = 1;
52 return (0);
53 }
54 *errp = 0;
55
56 memset(s: &time, c: 0, n: sizeof time);
57 time.tm_year = datepart(cp + 0, 4, 1990, 9999, errp) - 1900;
58 time.tm_mon = datepart(cp + 4, 2, 01, 12, errp) - 1;
59 time.tm_mday = datepart(cp + 6, 2, 01, 31, errp);
60 time.tm_hour = datepart(cp + 8, 2, 00, 23, errp);
61 time.tm_min = datepart(cp + 10, 2, 00, 59, errp);
62 time.tm_sec = datepart(cp + 12, 2, 00, 59, errp);
63 if (*errp) /*%< Any parse errors? */
64 return (0);
65
66 /*
67 * OK, now because timegm() is not available in all environments,
68 * we will do it by hand. Roll up sleeves, curse the gods, begin!
69 */
70
71#define SECS_PER_DAY ((uint32_t)24*60*60)
72#define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
73
74 result = time.tm_sec; /*%< Seconds */
75 result += time.tm_min * 60; /*%< Minutes */
76 result += time.tm_hour * (60*60); /*%< Hours */
77 result += (time.tm_mday - 1) * SECS_PER_DAY; /*%< Days */
78 /* Months are trickier. Look without leaping, then leap */
79 mdays = 0;
80 for (i = 0; i < time.tm_mon; i++)
81 mdays += days_per_month[i];
82 result += mdays * SECS_PER_DAY; /*%< Months */
83 if (time.tm_mon > 1 && isleap(1900+time.tm_year))
84 result += SECS_PER_DAY; /*%< Add leapday for this year */
85 /* First figure years without leapdays, then add them in. */
86 /* The loop is slow, FIXME, but simple and accurate. */
87 result += (time.tm_year - 70) * (SECS_PER_DAY*365); /*%< Years */
88 for (i = 70; i < time.tm_year; i++)
89 if (isleap(1900+i))
90 result += SECS_PER_DAY; /*%< Add leapday for prev year */
91 return (result);
92}
93
94/* Private. */
95
96/*%
97 * Parse part of a date. Set error flag if any error.
98 * Don't reset the flag if there is no error.
99 */
100static int
101datepart(const char *buf, int size, int min, int max, int *errp) {
102 int result = 0;
103 int i;
104
105 for (i = 0; i < size; i++) {
106 if (!isdigit((unsigned char)(buf[i])))
107 *errp = 1;
108 result = (result * 10) + buf[i] - '0';
109 }
110 if (result < min)
111 *errp = 1;
112 if (result > max)
113 *errp = 1;
114 return (result);
115}
116
117/*! \file */
118

source code of glibc/resolv/ns_date.c