1 /* $OpenBSD: rcstime.c,v 1.6 2016/08/26 09:02:54 guenther Exp $ */
2 /*
3 * Copyright (c) 2006 Joris Vink <joris@openbsd.org>
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 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. The name of the author may not be used to endorse or promote products
13 * derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
16 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
17 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
18 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
21 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
22 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
23 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
24 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <err.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <time.h>
31
32 #include "rcs.h"
33
34 void
rcs_set_tz(char * tz,struct rcs_delta * rdp,struct tm * tb)35 rcs_set_tz(char *tz, struct rcs_delta *rdp, struct tm *tb)
36 {
37 int tzone;
38 int pos;
39 char *h, *m;
40 const char *errstr;
41 struct tm *ltb;
42 time_t now;
43
44 if (!strcmp(tz, "LT")) {
45 now = mktime(&rdp->rd_date);
46 ltb = localtime(&now);
47 ltb->tm_hour += ((int)ltb->tm_gmtoff/3600);
48 memcpy(tb, ltb, sizeof(*tb));
49 } else {
50 pos = 0;
51 switch (*tz) {
52 case '-':
53 break;
54 case '+':
55 pos = 1;
56 break;
57 default:
58 errx(1, "%s: not a known time zone", tz);
59 }
60
61 h = (tz + 1);
62 if ((m = strrchr(tz, ':')) != NULL)
63 *(m++) = '\0';
64
65 memcpy(tb, &rdp->rd_date, sizeof(*tb));
66
67 tzone = strtonum(h, -23, 23, &errstr);
68 if (errstr)
69 errx(1, "%s: not a known time zone", tz);
70
71 if (pos) {
72 tb->tm_hour += tzone;
73 tb->tm_gmtoff += (tzone * 3600);
74 } else {
75 tb->tm_hour -= tzone;
76 tb->tm_gmtoff -= (tzone * 3600);
77 }
78
79 if ((tb->tm_hour >= 24) || (tb->tm_hour <= -24))
80 tb->tm_hour = 0;
81
82 if (m != NULL) {
83 tzone = strtonum(m, 0, 59, &errstr);
84 if (errstr)
85 errx(1, "%s: not a known minute", m);
86
87 if ((tb->tm_min + tzone) >= 60) {
88 tb->tm_hour++;
89 tb->tm_min -= (60 - tzone);
90 } else
91 tb->tm_min += tzone;
92
93 tb->tm_gmtoff += (tzone*60);
94 }
95 }
96 }
97