1 /*
2 +----------------------------------------------------------------------+
3 | PHP Version 5 |
4 +----------------------------------------------------------------------+
5 | Copyright (c) 1997-2014 The PHP Group |
6 +----------------------------------------------------------------------+
7 | This source file is subject to version 3.01 of the PHP license, |
8 | that is bundled with this package in the file LICENSE, and is |
9 | available through the world-wide-web at the following url: |
10 | http://www.php.net/license/3_01.txt |
11 | If you did not receive a copy of the PHP license and are unable to |
12 | obtain it through the world-wide-web, please send a note to |
13 | license@php.net so we can mail you a copy immediately. |
14 +----------------------------------------------------------------------+
15 | Authors: Derick Rethans <derick@derickrethans.nl> |
16 +----------------------------------------------------------------------+
17 */
18
19 /* $Id$ */
20
21 #include "timelib.h"
22 #include <math.h>
23
timelib_diff(timelib_time * one,timelib_time * two)24 timelib_rel_time *timelib_diff(timelib_time *one, timelib_time *two)
25 {
26 timelib_rel_time *rt;
27 timelib_time *swp;
28 timelib_sll dst_corr = 0 ,dst_h_corr = 0, dst_m_corr = 0;
29 timelib_time one_backup, two_backup;
30
31 rt = timelib_rel_time_ctor();
32 rt->invert = 0;
33 if (one->sse > two->sse) {
34 swp = two;
35 two = one;
36 one = swp;
37 rt->invert = 1;
38 }
39
40 /* Calculate correction for DST change over, but only if the TZ type is ID
41 * and it's the same */
42 if (one->zone_type == 3 && two->zone_type == 3
43 && (strcmp(one->tz_info->name, two->tz_info->name) == 0)
44 && (one->z != two->z))
45 {
46 dst_corr = two->z - one->z;
47 dst_h_corr = dst_corr / 3600;
48 dst_m_corr = (dst_corr % 3600) / 60;
49 }
50
51 /* Save old TZ info */
52 memcpy(&one_backup, one, sizeof(one_backup));
53 memcpy(&two_backup, two, sizeof(two_backup));
54
55 timelib_apply_localtime(one, 0);
56 timelib_apply_localtime(two, 0);
57
58 rt->y = two->y - one->y;
59 rt->m = two->m - one->m;
60 rt->d = two->d - one->d;
61 rt->h = two->h - one->h;
62 rt->i = two->i - one->i;
63 rt->s = two->s - one->s;
64 if (one_backup.dst == 0 && two_backup.dst == 1 && two->sse >= one->sse + 86400 - dst_corr) {
65 rt->h += dst_h_corr;
66 rt->i += dst_m_corr;
67 }
68
69 rt->days = abs(floor((one->sse - two->sse - (dst_h_corr * 3600) - (dst_m_corr * 60)) / 86400));
70
71 timelib_do_rel_normalize(rt->invert ? one : two, rt);
72
73 /* We need to do this after normalisation otherwise we can't get "24H" */
74 if (one_backup.dst == 1 && two_backup.dst == 0 && two->sse >= one->sse + 86400) {
75 if (two->sse < one->sse + 86400 - dst_corr) {
76 rt->d--;
77 rt->h = 24;
78 } else {
79 rt->h += dst_h_corr;
80 rt->i += dst_m_corr;
81 }
82 }
83
84 /* Restore old TZ info */
85 memcpy(one, &one_backup, sizeof(one_backup));
86 memcpy(two, &two_backup, sizeof(two_backup));
87
88 return rt;
89 }
90
timelib_add(timelib_time * old_time,timelib_rel_time * interval)91 timelib_time *timelib_add(timelib_time *old_time, timelib_rel_time *interval)
92 {
93 int bias = 1;
94 timelib_time *t = timelib_time_clone(old_time);
95
96 if (interval->have_weekday_relative || interval->have_special_relative) {
97 memcpy(&t->relative, interval, sizeof(struct timelib_rel_time));
98 } else {
99 if (interval->invert) {
100 bias = -1;
101 }
102 memset(&t->relative, 0, sizeof(struct timelib_rel_time));
103 t->relative.y = interval->y * bias;
104 t->relative.m = interval->m * bias;
105 t->relative.d = interval->d * bias;
106 t->relative.h = interval->h * bias;
107 t->relative.i = interval->i * bias;
108 t->relative.s = interval->s * bias;
109 }
110 t->have_relative = 1;
111 t->sse_uptodate = 0;
112
113 timelib_update_ts(t, NULL);
114
115 // printf("%lld %lld %d\n", old_time->dst, t->dst, (t->sse - old_time->sse));
116 /* Adjust for backwards DST changeover */
117 if (old_time->dst == 1 && t->dst == 0 && !interval->y && !interval->m && !interval->d) {
118 t->sse -= old_time->z;
119 t->sse += t->z;
120 }
121
122 timelib_update_from_sse(t);
123 t->have_relative = 0;
124
125 return t;
126 }
127
timelib_sub(timelib_time * old_time,timelib_rel_time * interval)128 timelib_time *timelib_sub(timelib_time *old_time, timelib_rel_time *interval)
129 {
130 int bias = 1;
131 timelib_time *t = timelib_time_clone(old_time);
132
133 if (interval->invert) {
134 bias = -1;
135 }
136
137 memset(&t->relative, 0, sizeof(struct timelib_rel_time));
138 t->relative.y = 0 - (interval->y * bias);
139 t->relative.m = 0 - (interval->m * bias);
140 t->relative.d = 0 - (interval->d * bias);
141 t->relative.h = 0 - (interval->h * bias);
142 t->relative.i = 0 - (interval->i * bias);
143 t->relative.s = 0 - (interval->s * bias);
144 t->have_relative = 1;
145 t->sse_uptodate = 0;
146
147 timelib_update_ts(t, NULL);
148
149 /* Adjust for backwards DST changeover */
150 if (old_time->dst == 1 && t->dst == 0 && !interval->y && !interval->m && !interval->d) {
151 t->sse -= old_time->z;
152 t->sse += t->z;
153 }
154 /* Adjust for forwards DST changeover */
155 if (old_time->dst == 0 && t->dst == 1 && !interval->y && !interval->m && !interval->d ) {
156 t->sse -= old_time->z;
157 t->sse += t->z;
158 }
159
160 timelib_update_from_sse(t);
161
162 t->have_relative = 0;
163
164 return t;
165 }
166
