xref: /PHP-5.3/ext/date/lib/unixtime2tm.c (revision a2045ff3)
1 /*
2    +----------------------------------------------------------------------+
3    | PHP Version 5                                                        |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1997-2013 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 
23 #include <stdio.h>
24 
25 #ifdef HAVE_STDLIB_H
26 #include <stdlib.h>
27 #endif
28 
29 #ifdef HAVE_STRING_H
30 #include <string.h>
31 #else
32 #include <strings.h>
33 #endif
34 
35 static int month_tab_leap[12] = { -1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
36 static int month_tab[12] =      { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
37 
38 
39 /* Converts a Unix timestamp value into broken down time, in GMT */
timelib_unixtime2gmt(timelib_time * tm,timelib_sll ts)40 void timelib_unixtime2gmt(timelib_time* tm, timelib_sll ts)
41 {
42 	timelib_sll days, remainder, tmp_days;
43 	timelib_sll cur_year = 1970;
44 	timelib_sll i;
45 	timelib_sll hours, minutes, seconds;
46 	int *months;
47 
48 	days = ts / SECS_PER_DAY;
49 	remainder = ts - (days * SECS_PER_DAY);
50 	if (ts < 0 && remainder == 0) {
51 		days++;
52 		remainder -= SECS_PER_DAY;
53 	}
54 	TIMELIB_DEBUG(printf("days=%lld, rem=%lld\n", days, remainder););
55 
56 	if (ts >= 0) {
57 		tmp_days = days + 1;
58 
59 		if (tmp_days >= DAYS_PER_LYEAR_PERIOD || tmp_days <= -DAYS_PER_LYEAR_PERIOD) {
60 			cur_year += YEARS_PER_LYEAR_PERIOD * (tmp_days / DAYS_PER_LYEAR_PERIOD);
61 			tmp_days -= DAYS_PER_LYEAR_PERIOD * (tmp_days / DAYS_PER_LYEAR_PERIOD);
62 		}
63 
64 		while (tmp_days >= DAYS_PER_LYEAR) {
65 			cur_year++;
66 			if (timelib_is_leap(cur_year)) {
67 				tmp_days -= DAYS_PER_LYEAR;
68 			} else {
69 				tmp_days -= DAYS_PER_YEAR;
70 			}
71 		}
72 	} else {
73 		tmp_days = days;
74 
75 		/* Guess why this might be for, it has to do with a pope ;-). It's also
76 		 * only valid for Great Brittain and it's colonies. It needs fixing for
77 		 * other locales. *sigh*, why is this crap so complex! */
78 		/*
79 		if (ts <= TIMELIB_LL_CONST(-6857352000)) {
80 			tmp_days -= 11;
81 		}
82 		*/
83 
84 		while (tmp_days <= 0) {
85 			if (tmp_days < -1460970) {
86 				cur_year -= 4000;
87 				TIMELIB_DEBUG(printf("tmp_days=%lld, year=%lld\n", tmp_days, cur_year););
88 				tmp_days += 1460970;
89 			} else {
90 				cur_year--;
91 				TIMELIB_DEBUG(printf("tmp_days=%lld, year=%lld\n", tmp_days, cur_year););
92 				if (timelib_is_leap(cur_year)) {
93 					tmp_days += DAYS_PER_LYEAR;
94 				} else {
95 					tmp_days += DAYS_PER_YEAR;
96 				}
97 			}
98 		}
99 		remainder += SECS_PER_DAY;
100 	}
101 	TIMELIB_DEBUG(printf("tmp_days=%lld, year=%lld\n", tmp_days, cur_year););
102 
103 	months = timelib_is_leap(cur_year) ? month_tab_leap : month_tab;
104 	if (timelib_is_leap(cur_year) && cur_year < 1970) {
105 		tmp_days--;
106 	}
107 	i = 11;
108 	while (i > 0) {
109 		TIMELIB_DEBUG(printf("month=%lld (%d)\n", i, months[i]););
110 		if (tmp_days > months[i]) {
111 			break;
112 		}
113 		i--;
114 	}
115 	TIMELIB_DEBUG(printf("A: ts=%lld, year=%lld, month=%lld, day=%lld,", ts, cur_year, i + 1, tmp_days - months[i]););
116 
117 	/* That was the date, now we do the tiiiime */
118 	hours = remainder / 3600;
119 	minutes = (remainder - hours * 3600) / 60;
120 	seconds = remainder % 60;
121 	TIMELIB_DEBUG(printf(" hour=%lld, minute=%lld, second=%lld\n", hours, minutes, seconds););
122 
123 	tm->y = cur_year;
124 	tm->m = i + 1;
125 	tm->d = tmp_days - months[i];
126 	tm->h = hours;
127 	tm->i = minutes;
128 	tm->s = seconds;
129 	tm->z = 0;
130 	tm->dst = 0;
131 	tm->sse = ts;
132 	tm->sse_uptodate = 1;
133 	tm->tim_uptodate = 1;
134 	tm->is_localtime = 0;
135 }
136 
timelib_update_from_sse(timelib_time * tm)137 void timelib_update_from_sse(timelib_time *tm)
138 {
139 	timelib_sll sse;
140 
141 	sse = tm->sse;
142 
143 	switch (tm->zone_type) {
144 		case TIMELIB_ZONETYPE_ABBR:
145 		case TIMELIB_ZONETYPE_OFFSET: {
146 			int z = tm->z;
147 			signed int dst = tm->dst;
148 
149 			timelib_unixtime2gmt(tm, tm->sse - (tm->z * 60) + (tm->dst * 3600));
150 
151 			tm->z = z;
152 			tm->dst = dst;
153 			goto cleanup;
154 		}
155 
156 		case TIMELIB_ZONETYPE_ID: {
157 			timelib_time_offset *gmt_offset;
158 
159 			gmt_offset = timelib_get_time_zone_info(tm->sse, tm->tz_info);
160 			timelib_unixtime2gmt(tm, tm->sse + gmt_offset->offset);
161 			timelib_time_offset_dtor(gmt_offset);
162 
163 			goto cleanup;
164 		}
165 
166 		default:
167 			timelib_unixtime2gmt(tm, tm->sse);
168 			goto cleanup;
169 	}
170 cleanup:
171 	tm->sse = sse;
172 	tm->is_localtime = 1;
173 	tm->have_zone = 1;
174 }
175 
timelib_unixtime2local(timelib_time * tm,timelib_sll ts)176 void timelib_unixtime2local(timelib_time *tm, timelib_sll ts)
177 {
178 	timelib_time_offset *gmt_offset;
179 	timelib_tzinfo      *tz = tm->tz_info;
180 
181 	switch (tm->zone_type) {
182 		case TIMELIB_ZONETYPE_ABBR:
183 		case TIMELIB_ZONETYPE_OFFSET: {
184 			int z = tm->z;
185 			signed int dst = tm->dst;
186 
187 			timelib_unixtime2gmt(tm, ts - (tm->z * 60) + (tm->dst * 3600));
188 
189 			tm->z = z;
190 			tm->dst = dst;
191 			break;
192 		}
193 
194 		case TIMELIB_ZONETYPE_ID:
195 			gmt_offset = timelib_get_time_zone_info(ts, tz);
196 			timelib_unixtime2gmt(tm, ts + gmt_offset->offset);
197 
198 			/* we need to reset the sse here as unixtime2gmt modifies it */
199 			tm->sse = ts;
200 			tm->dst = gmt_offset->is_dst;
201 			tm->z = gmt_offset->offset;
202 			tm->tz_info = tz;
203 
204 			timelib_time_tz_abbr_update(tm, gmt_offset->abbr);
205 			timelib_time_offset_dtor(gmt_offset);
206 			break;
207 
208 		default:
209 			tm->is_localtime = 0;
210 			tm->have_zone = 0;
211 			return;
212 	}
213 
214 	tm->is_localtime = 1;
215 	tm->have_zone = 1;
216 }
217 
timelib_set_timezone(timelib_time * t,timelib_tzinfo * tz)218 void timelib_set_timezone(timelib_time *t, timelib_tzinfo *tz)
219 {
220 	timelib_time_offset *gmt_offset;
221 
222 	gmt_offset = timelib_get_time_zone_info(t->sse, tz);
223 	t->z = gmt_offset->offset;
224 /*
225 	if (t->dst != gmt_offset->is_dst) {
226 		printf("ERROR (%d, %d)\n", t->dst, gmt_offset->is_dst);
227 		exit(1);
228 	}
229 */
230 	t->dst = gmt_offset->is_dst;
231 	t->tz_info = tz;
232 	if (t->tz_abbr) {
233 		free(t->tz_abbr);
234 	}
235 	t->tz_abbr = strdup(gmt_offset->abbr);
236 	timelib_time_offset_dtor(gmt_offset);
237 
238 	t->have_zone = 1;
239 	t->zone_type = TIMELIB_ZONETYPE_ID;
240 }
241 
242 /* Converts the time stored in the struct to localtime if localtime = true,
243  * otherwise it converts it to gmttime. This is only done when necessary
244  * ofcourse. */
timelib_apply_localtime(timelib_time * t,unsigned int localtime)245 int timelib_apply_localtime(timelib_time *t, unsigned int localtime)
246 {
247 	if (localtime) {
248 		/* Converting from GMT time to local time */
249 		TIMELIB_DEBUG(printf("Converting from GMT time to local time\n"););
250 
251 		/* Check if TZ is set */
252 		if (!t->tz_info) {
253 			TIMELIB_DEBUG(printf("E: No timezone configured, can't switch to local time\n"););
254 			return -1;
255 		}
256 
257 		timelib_unixtime2local(t, t->sse);
258 	} else {
259 		/* Converting from local time to GMT time */
260 		TIMELIB_DEBUG(printf("Converting from local time to GMT time\n"););
261 
262 		timelib_unixtime2gmt(t, t->sse);
263 	}
264 	return 0;
265 }
266