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 #ifndef lint
19 static const char rcsid[] = "$Id: ns_date.c,v 1.6 2005/04/27 04:56:39 sra Exp $";
20 #endif
21
22 /* Import. */
23
24 #include "port_before.h"
25
26 #include <arpa/nameser.h>
27
28 #include <ctype.h>
29 #include <errno.h>
30 #include <stdio.h>
31 #include <string.h>
32 #include <time.h>
33
34 #include "port_after.h"
35
36 #ifdef SPRINTF_CHAR
37 # define SPRINTF(x) strlen(sprintf/**/x)
38 #else
39 # define SPRINTF(x) ((size_t)sprintf x)
40 #endif
41
42 /* Forward. */
43
44 static int datepart(const char *, int, int, int, int *);
45
46 /* Public. */
47
48 /*%
49 * Convert a date in ASCII into the number of seconds since
50 * 1 January 1970 (GMT assumed). Format is yyyymmddhhmmss, all
51 * digits required, no spaces allowed.
52 */
53
54 u_int32_t
ns_datetosecs(const char * cp,int * errp)55 ns_datetosecs(const char *cp, int *errp) {
56 struct tm time;
57 u_int32_t result;
58 int mdays, i;
59 static const int days_per_month[12] =
60 {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
61
62 if (strlen(cp) != 14U) {
63 *errp = 1;
64 return (0);
65 }
66 *errp = 0;
67
68 memset(&time, 0, sizeof time);
69 time.tm_year = datepart(cp + 0, 4, 1990, 9999, errp) - 1900;
70 time.tm_mon = datepart(cp + 4, 2, 01, 12, errp) - 1;
71 time.tm_mday = datepart(cp + 6, 2, 01, 31, errp);
72 time.tm_hour = datepart(cp + 8, 2, 00, 23, errp);
73 time.tm_min = datepart(cp + 10, 2, 00, 59, errp);
74 time.tm_sec = datepart(cp + 12, 2, 00, 59, errp);
75 if (*errp) /*%< Any parse errors? */
76 return (0);
77
78 /*
79 * OK, now because timegm() is not available in all environments,
80 * we will do it by hand. Roll up sleeves, curse the gods, begin!
81 */
82
83 #define SECS_PER_DAY ((u_int32_t)24*60*60)
84 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
85
86 result = time.tm_sec; /*%< Seconds */
87 result += time.tm_min * 60; /*%< Minutes */
88 result += time.tm_hour * (60*60); /*%< Hours */
89 result += (time.tm_mday - 1) * SECS_PER_DAY; /*%< Days */
90 /* Months are trickier. Look without leaping, then leap */
91 mdays = 0;
92 for (i = 0; i < time.tm_mon; i++)
93 mdays += days_per_month[i];
94 result += mdays * SECS_PER_DAY; /*%< Months */
95 if (time.tm_mon > 1 && isleap(1900+time.tm_year))
96 result += SECS_PER_DAY; /*%< Add leapday for this year */
97 /* First figure years without leapdays, then add them in. */
98 /* The loop is slow, FIXME, but simple and accurate. */
99 result += (time.tm_year - 70) * (SECS_PER_DAY*365); /*%< Years */
100 for (i = 70; i < time.tm_year; i++)
101 if (isleap(1900+i))
102 result += SECS_PER_DAY; /*%< Add leapday for prev year */
103 return (result);
104 }
105
106 /* Private. */
107
108 /*%
109 * Parse part of a date. Set error flag if any error.
110 * Don't reset the flag if there is no error.
111 */
112 static int
datepart(const char * buf,int size,int min,int max,int * errp)113 datepart(const char *buf, int size, int min, int max, int *errp) {
114 int result = 0;
115 int i;
116
117 for (i = 0; i < size; i++) {
118 if (!isdigit((unsigned char)(buf[i])))
119 *errp = 1;
120 result = (result * 10) + buf[i] - '0';
121 }
122 if (result < min)
123 *errp = 1;
124 if (result > max)
125 *errp = 1;
126 return (result);
127 }
128
129 /*! \file */
130