xref: /PHP-5.4/ext/date/lib/parse_tz.c (revision c0d060f5)
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 
23 #include <stdio.h>
24 
25 #ifdef HAVE_LOCALE_H
26 #include <locale.h>
27 #endif
28 
29 #ifdef HAVE_STRING_H
30 #include <string.h>
31 #else
32 #include <strings.h>
33 #endif
34 #include "timezonedb.h"
35 
36 #if (defined(__APPLE__) || defined(__APPLE_CC__)) && (defined(__BIG_ENDIAN__) || defined(__LITTLE_ENDIAN__))
37 # if defined(__LITTLE_ENDIAN__)
38 #  undef WORDS_BIGENDIAN
39 # else
40 #  if defined(__BIG_ENDIAN__)
41 #   define WORDS_BIGENDIAN
42 #  endif
43 # endif
44 #endif
45 
46 #ifdef WORDS_BIGENDIAN
47 #define timelib_conv_int(l) (l)
48 #else
49 #define timelib_conv_int(l) ((l & 0x000000ff) << 24) + ((l & 0x0000ff00) << 8) + ((l & 0x00ff0000) >> 8) + ((l & 0xff000000) >> 24)
50 #endif
51 
read_preamble(const unsigned char ** tzf,timelib_tzinfo * tz)52 static void read_preamble(const unsigned char **tzf, timelib_tzinfo *tz)
53 {
54 	/* skip ID */
55 	*tzf += 4;
56 
57 	/* read BC flag */
58 	tz->bc = (**tzf == '\1');
59 	*tzf += 1;
60 
61 	/* read country code */
62 	memcpy(tz->location.country_code, *tzf, 2);
63 	tz->location.country_code[2] = '\0';
64 	*tzf += 2;
65 
66 	/* skip read of preamble */
67 	*tzf += 13;
68 }
69 
read_header(const unsigned char ** tzf,timelib_tzinfo * tz)70 static void read_header(const unsigned char **tzf, timelib_tzinfo *tz)
71 {
72 	uint32_t buffer[6];
73 
74 	memcpy(&buffer, *tzf, sizeof(buffer));
75 	tz->ttisgmtcnt = timelib_conv_int(buffer[0]);
76 	tz->ttisstdcnt = timelib_conv_int(buffer[1]);
77 	tz->leapcnt    = timelib_conv_int(buffer[2]);
78 	tz->timecnt    = timelib_conv_int(buffer[3]);
79 	tz->typecnt    = timelib_conv_int(buffer[4]);
80 	tz->charcnt    = timelib_conv_int(buffer[5]);
81 	*tzf += sizeof(buffer);
82 }
83 
read_transistions(const unsigned char ** tzf,timelib_tzinfo * tz)84 static void read_transistions(const unsigned char **tzf, timelib_tzinfo *tz)
85 {
86 	int32_t *buffer = NULL;
87 	uint32_t i;
88 	unsigned char *cbuffer = NULL;
89 
90 	if (tz->timecnt) {
91 		buffer = (int32_t*) malloc(tz->timecnt * sizeof(int32_t));
92 		if (!buffer) {
93 			return;
94 		}
95 		memcpy(buffer, *tzf, sizeof(int32_t) * tz->timecnt);
96 		*tzf += (sizeof(int32_t) * tz->timecnt);
97 		for (i = 0; i < tz->timecnt; i++) {
98 			buffer[i] = timelib_conv_int(buffer[i]);
99 		}
100 
101 		cbuffer = (unsigned char*) malloc(tz->timecnt * sizeof(unsigned char));
102 		if (!cbuffer) {
103 			free(buffer);
104 			return;
105 		}
106 		memcpy(cbuffer, *tzf, sizeof(unsigned char) * tz->timecnt);
107 		*tzf += sizeof(unsigned char) * tz->timecnt;
108 	}
109 
110 	tz->trans = buffer;
111 	tz->trans_idx = cbuffer;
112 }
113 
read_types(const unsigned char ** tzf,timelib_tzinfo * tz)114 static void read_types(const unsigned char **tzf, timelib_tzinfo *tz)
115 {
116 	unsigned char *buffer;
117 	int32_t *leap_buffer;
118 	unsigned int i, j;
119 
120 	buffer = (unsigned char*) malloc(tz->typecnt * sizeof(unsigned char) * 6);
121 	if (!buffer) {
122 		return;
123 	}
124 	memcpy(buffer, *tzf, sizeof(unsigned char) * 6 * tz->typecnt);
125 	*tzf += sizeof(unsigned char) * 6 * tz->typecnt;
126 
127 	tz->type = (ttinfo*) malloc(tz->typecnt * sizeof(struct ttinfo));
128 	if (!tz->type) {
129 		free(buffer);
130 		return;
131 	}
132 
133 	for (i = 0; i < tz->typecnt; i++) {
134 		j = i * 6;
135 		tz->type[i].offset = (buffer[j] * 16777216) + (buffer[j + 1] * 65536) + (buffer[j + 2] * 256) + buffer[j + 3];
136 		tz->type[i].isdst = buffer[j + 4];
137 		tz->type[i].abbr_idx = buffer[j + 5];
138 	}
139 	free(buffer);
140 
141 	tz->timezone_abbr = (char*) malloc(tz->charcnt);
142 	if (!tz->timezone_abbr) {
143 		return;
144 	}
145 	memcpy(tz->timezone_abbr, *tzf, sizeof(char) * tz->charcnt);
146 	*tzf += sizeof(char) * tz->charcnt;
147 
148 	if (tz->leapcnt) {
149 		leap_buffer = (int32_t *) malloc(tz->leapcnt * 2 * sizeof(int32_t));
150 		if (!leap_buffer) {
151 			return;
152 		}
153 		memcpy(leap_buffer, *tzf, sizeof(int32_t) * tz->leapcnt * 2);
154 		*tzf += sizeof(int32_t) * tz->leapcnt * 2;
155 
156 		tz->leap_times = (tlinfo*) malloc(tz->leapcnt * sizeof(tlinfo));
157 		if (!tz->leap_times) {
158 			free(leap_buffer);
159 			return;
160 		}
161 		for (i = 0; i < tz->leapcnt; i++) {
162 			tz->leap_times[i].trans = timelib_conv_int(leap_buffer[i * 2]);
163 			tz->leap_times[i].offset = timelib_conv_int(leap_buffer[i * 2 + 1]);
164 		}
165 		free(leap_buffer);
166 	}
167 
168 	if (tz->ttisstdcnt) {
169 		buffer = (unsigned char*) malloc(tz->ttisstdcnt * sizeof(unsigned char));
170 		if (!buffer) {
171 			return;
172 		}
173 		memcpy(buffer, *tzf, sizeof(unsigned char) * tz->ttisstdcnt);
174 		*tzf += sizeof(unsigned char) * tz->ttisstdcnt;
175 
176 		for (i = 0; i < tz->ttisstdcnt; i++) {
177 			tz->type[i].isstdcnt = buffer[i];
178 		}
179 		free(buffer);
180 	}
181 
182 	if (tz->ttisgmtcnt) {
183 		buffer = (unsigned char*) malloc(tz->ttisgmtcnt * sizeof(unsigned char));
184 		if (!buffer) {
185 			return;
186 		}
187 		memcpy(buffer, *tzf, sizeof(unsigned char) * tz->ttisgmtcnt);
188 		*tzf += sizeof(unsigned char) * tz->ttisgmtcnt;
189 
190 		for (i = 0; i < tz->ttisgmtcnt; i++) {
191 			tz->type[i].isgmtcnt = buffer[i];
192 		}
193 		free(buffer);
194 	}
195 }
196 
read_location(const unsigned char ** tzf,timelib_tzinfo * tz)197 static void read_location(const unsigned char **tzf, timelib_tzinfo *tz)
198 {
199 	uint32_t buffer[3];
200 	uint32_t comments_len;
201 
202 	memcpy(&buffer, *tzf, sizeof(buffer));
203 	tz->location.latitude = timelib_conv_int(buffer[0]);
204 	tz->location.latitude = (tz->location.latitude / 100000) - 90;
205 	tz->location.longitude = timelib_conv_int(buffer[1]);
206 	tz->location.longitude = (tz->location.longitude / 100000) - 180;
207 	comments_len = timelib_conv_int(buffer[2]);
208 	*tzf += sizeof(buffer);
209 
210 	tz->location.comments = malloc(comments_len + 1);
211 	memcpy(tz->location.comments, *tzf, comments_len);
212 	tz->location.comments[comments_len] = '\0';
213 	*tzf += comments_len;
214 }
215 
timelib_dump_tzinfo(timelib_tzinfo * tz)216 void timelib_dump_tzinfo(timelib_tzinfo *tz)
217 {
218 	uint32_t i;
219 
220 	printf("Country Code:      %s\n", tz->location.country_code);
221 	printf("Geo Location:      %f,%f\n", tz->location.latitude, tz->location.longitude);
222 	printf("Comments:\n%s\n",          tz->location.comments);
223 	printf("BC:                %s\n",  tz->bc ? "" : "yes");
224 	printf("UTC/Local count:   %lu\n", (unsigned long) tz->ttisgmtcnt);
225 	printf("Std/Wall count:    %lu\n", (unsigned long) tz->ttisstdcnt);
226 	printf("Leap.sec. count:   %lu\n", (unsigned long) tz->leapcnt);
227 	printf("Trans. count:      %lu\n", (unsigned long) tz->timecnt);
228 	printf("Local types count: %lu\n", (unsigned long) tz->typecnt);
229 	printf("Zone Abbr. count:  %lu\n", (unsigned long) tz->charcnt);
230 
231 	printf ("%8s (%12s) = %3d [%5ld %1d %3d '%s' (%d,%d)]\n",
232 		"", "", 0,
233 		(long int) tz->type[0].offset,
234 		tz->type[0].isdst,
235 		tz->type[0].abbr_idx,
236 		&tz->timezone_abbr[tz->type[0].abbr_idx],
237 		tz->type[0].isstdcnt,
238 		tz->type[0].isgmtcnt
239 		);
240 	for (i = 0; i < tz->timecnt; i++) {
241 		printf ("%08X (%12d) = %3d [%5ld %1d %3d '%s' (%d,%d)]\n",
242 			tz->trans[i], tz->trans[i], tz->trans_idx[i],
243 			(long int) tz->type[tz->trans_idx[i]].offset,
244 			tz->type[tz->trans_idx[i]].isdst,
245 			tz->type[tz->trans_idx[i]].abbr_idx,
246 			&tz->timezone_abbr[tz->type[tz->trans_idx[i]].abbr_idx],
247 			tz->type[tz->trans_idx[i]].isstdcnt,
248 			tz->type[tz->trans_idx[i]].isgmtcnt
249 			);
250 	}
251 	for (i = 0; i < tz->leapcnt; i++) {
252 		printf ("%08X (%12ld) = %d\n",
253 			tz->leap_times[i].trans,
254 			(long) tz->leap_times[i].trans,
255 			tz->leap_times[i].offset);
256 	}
257 }
258 
seek_to_tz_position(const unsigned char ** tzf,char * timezone,const timelib_tzdb * tzdb)259 static int seek_to_tz_position(const unsigned char **tzf, char *timezone, const timelib_tzdb *tzdb)
260 {
261 	int left = 0, right = tzdb->index_size - 1;
262 #ifdef HAVE_SETLOCALE
263 	char *cur_locale = NULL, *tmp;
264 
265 	tmp = setlocale(LC_CTYPE, NULL);
266 	if (tmp) {
267 		cur_locale = strdup(tmp);
268 	}
269 	setlocale(LC_CTYPE, "C");
270 #endif
271 
272 	do {
273 		int mid = ((unsigned)left + right) >> 1;
274 		int cmp = strcasecmp(timezone, tzdb->index[mid].id);
275 
276 		if (cmp < 0) {
277 			right = mid - 1;
278 		} else if (cmp > 0) {
279 			left = mid + 1;
280 		} else { /* (cmp == 0) */
281 			(*tzf) = &(tzdb->data[tzdb->index[mid].pos]);
282 #ifdef HAVE_SETLOCALE
283 			setlocale(LC_CTYPE, cur_locale);
284 			if (cur_locale) free(cur_locale);
285 #endif
286 			return 1;
287 		}
288 
289 	} while (left <= right);
290 
291 #ifdef HAVE_SETLOCALE
292 	setlocale(LC_CTYPE, cur_locale);
293 	if (cur_locale) free(cur_locale);
294 #endif
295 	return 0;
296 }
297 
timelib_builtin_db(void)298 const timelib_tzdb *timelib_builtin_db(void)
299 {
300 	return &timezonedb_builtin;
301 }
302 
timelib_timezone_builtin_identifiers_list(int * count)303 const timelib_tzdb_index_entry *timelib_timezone_builtin_identifiers_list(int *count)
304 {
305 	*count = sizeof(timezonedb_idx_builtin) / sizeof(*timezonedb_idx_builtin);
306 	return timezonedb_idx_builtin;
307 }
308 
timelib_timezone_id_is_valid(char * timezone,const timelib_tzdb * tzdb)309 int timelib_timezone_id_is_valid(char *timezone, const timelib_tzdb *tzdb)
310 {
311 	const unsigned char *tzf;
312 	return (seek_to_tz_position(&tzf, timezone, tzdb));
313 }
314 
timelib_parse_tzfile(char * timezone,const timelib_tzdb * tzdb)315 timelib_tzinfo *timelib_parse_tzfile(char *timezone, const timelib_tzdb *tzdb)
316 {
317 	const unsigned char *tzf;
318 	timelib_tzinfo *tmp;
319 
320 	if (seek_to_tz_position(&tzf, timezone, tzdb)) {
321 		tmp = timelib_tzinfo_ctor(timezone);
322 
323 		read_preamble(&tzf, tmp);
324 		read_header(&tzf, tmp);
325 		read_transistions(&tzf, tmp);
326 		read_types(&tzf, tmp);
327 		read_location(&tzf, tmp);
328 	} else {
329 		tmp = NULL;
330 	}
331 
332 	return tmp;
333 }
334 
fetch_timezone_offset(timelib_tzinfo * tz,timelib_sll ts,timelib_sll * transition_time)335 static ttinfo* fetch_timezone_offset(timelib_tzinfo *tz, timelib_sll ts, timelib_sll *transition_time)
336 {
337 	uint32_t i;
338 
339 	/* If there is no transistion time, we pick the first one, if that doesn't
340 	 * exist we return NULL */
341 	if (!tz->timecnt || !tz->trans) {
342 		*transition_time = 0;
343 		if (tz->typecnt == 1) {
344 			return &(tz->type[0]);
345 		}
346 		return NULL;
347 	}
348 
349 	/* If the TS is lower than the first transistion time, then we scan over
350 	 * all the transistion times to find the first non-DST one, or the first
351 	 * one in case there are only DST entries. Not sure which smartass came up
352 	 * with this idea in the first though :) */
353 	if (ts < tz->trans[0]) {
354 		uint32_t j;
355 
356 		*transition_time = 0;
357 		j = 0;
358 		while (j < tz->timecnt && tz->type[j].isdst) {
359 			++j;
360 		}
361 		if (j == tz->timecnt) {
362 			j = 0;
363 		}
364 		return &(tz->type[j]);
365 	}
366 
367 	/* In all other cases we loop through the available transtion times to find
368 	 * the correct entry */
369 	for (i = 0; i < tz->timecnt; i++) {
370 		if (ts < tz->trans[i]) {
371 			*transition_time = tz->trans[i - 1];
372 			return &(tz->type[tz->trans_idx[i - 1]]);
373 		}
374 	}
375 	*transition_time = tz->trans[tz->timecnt - 1];
376 	return &(tz->type[tz->trans_idx[tz->timecnt - 1]]);
377 }
378 
fetch_leaptime_offset(timelib_tzinfo * tz,timelib_sll ts)379 static tlinfo* fetch_leaptime_offset(timelib_tzinfo *tz, timelib_sll ts)
380 {
381 	int i;
382 
383 	if (!tz->leapcnt || !tz->leap_times) {
384 		return NULL;
385 	}
386 
387 	for (i = tz->leapcnt - 1; i > 0; i--) {
388 		if (ts > tz->leap_times[i].trans) {
389 			return &(tz->leap_times[i]);
390 		}
391 	}
392 	return NULL;
393 }
394 
timelib_timestamp_is_in_dst(timelib_sll ts,timelib_tzinfo * tz)395 int timelib_timestamp_is_in_dst(timelib_sll ts, timelib_tzinfo *tz)
396 {
397 	ttinfo *to;
398 	timelib_sll dummy;
399 
400 	if ((to = fetch_timezone_offset(tz, ts, &dummy))) {
401 		return to->isdst;
402 	}
403 	return -1;
404 }
405 
timelib_get_time_zone_info(timelib_sll ts,timelib_tzinfo * tz)406 timelib_time_offset *timelib_get_time_zone_info(timelib_sll ts, timelib_tzinfo *tz)
407 {
408 	ttinfo *to;
409 	tlinfo *tl;
410 	int32_t offset = 0, leap_secs = 0;
411 	char *abbr;
412 	timelib_time_offset *tmp = timelib_time_offset_ctor();
413 	timelib_sll                transistion_time;
414 
415 	if ((to = fetch_timezone_offset(tz, ts, &transistion_time))) {
416 		offset = to->offset;
417 		abbr = &(tz->timezone_abbr[to->abbr_idx]);
418 		tmp->is_dst = to->isdst;
419 		tmp->transistion_time = transistion_time;
420 	} else {
421 		offset = 0;
422 		abbr = tz->timezone_abbr;
423 		tmp->is_dst = 0;
424 		tmp->transistion_time = 0;
425 	}
426 
427 	if ((tl = fetch_leaptime_offset(tz, ts))) {
428 		leap_secs = -tl->offset;
429 	}
430 
431 	tmp->offset = offset;
432 	tmp->leap_secs = leap_secs;
433 	tmp->abbr = abbr ? strdup(abbr) : strdup("GMT");
434 
435 	return tmp;
436 }
437 
timelib_get_current_offset(timelib_time * t)438 timelib_sll timelib_get_current_offset(timelib_time *t)
439 {
440 	timelib_time_offset *gmt_offset;
441 	timelib_sll retval;
442 
443 	switch (t->zone_type) {
444 		case TIMELIB_ZONETYPE_ABBR:
445 		case TIMELIB_ZONETYPE_OFFSET:
446 			return (t->z + t->dst) * -60;
447 
448 		case TIMELIB_ZONETYPE_ID:
449 			gmt_offset = timelib_get_time_zone_info(t->sse, t->tz_info);
450 			retval = gmt_offset->offset;
451 			timelib_time_offset_dtor(gmt_offset);
452 			return retval;
453 
454 		default:
455 			return 0;
456 	}
457 }
458