1 /*
2 * The MIT License (MIT)
3 *
4 * Copyright (c) 2015 Derick Rethans
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "timelib.h"
26
27 /* jan feb mrt apr may jun jul aug sep oct nov dec */
28 static int month_tab_leap[12] = { -1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
29 static int month_tab[12] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
30
31 /* dec jan feb mrt apr may jun jul aug sep oct nov dec */
32 static int days_in_month_leap[13] = { 31, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
33 static int days_in_month[13] = { 31, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
34
do_range_limit_fraction(double * fraction,timelib_sll * seconds)35 static void do_range_limit_fraction(double *fraction, timelib_sll *seconds)
36 {
37 if (*fraction < 0) {
38 *fraction += 1;
39 *seconds -= 1;
40 }
41 if (*fraction > 1) {
42 *fraction -= 1;
43 *seconds += 1;
44 }
45 }
46
do_range_limit(timelib_sll start,timelib_sll end,timelib_sll adj,timelib_sll * a,timelib_sll * b)47 static void do_range_limit(timelib_sll start, timelib_sll end, timelib_sll adj, timelib_sll *a, timelib_sll *b)
48 {
49 if (*a < start) {
50 *b -= (start - *a - 1) / adj + 1;
51 *a += adj * ((start - *a - 1) / adj + 1);
52 }
53 if (*a >= end) {
54 *b += *a / adj;
55 *a -= adj * (*a / adj);
56 }
57 }
58
inc_month(timelib_sll * y,timelib_sll * m)59 static void inc_month(timelib_sll *y, timelib_sll *m)
60 {
61 (*m)++;
62 if (*m > 12) {
63 *m -= 12;
64 (*y)++;
65 }
66 }
67
dec_month(timelib_sll * y,timelib_sll * m)68 static void dec_month(timelib_sll *y, timelib_sll *m)
69 {
70 (*m)--;
71 if (*m < 1) {
72 *m += 12;
73 (*y)--;
74 }
75 }
76
do_range_limit_days_relative(timelib_sll * base_y,timelib_sll * base_m,timelib_sll * y,timelib_sll * m,timelib_sll * d,timelib_sll invert)77 static void do_range_limit_days_relative(timelib_sll *base_y, timelib_sll *base_m, timelib_sll *y, timelib_sll *m, timelib_sll *d, timelib_sll invert)
78 {
79 timelib_sll leapyear;
80 timelib_sll month, year;
81 timelib_sll days;
82
83 do_range_limit(1, 13, 12, base_m, base_y);
84
85 year = *base_y;
86 month = *base_m;
87
88 /*
89 printf( "S: Y%d M%d %d %d %d %d\n", year, month, *y, *m, *d, days);
90 */
91 if (!invert) {
92 while (*d < 0) {
93 dec_month(&year, &month);
94 leapyear = timelib_is_leap(year);
95 days = leapyear ? days_in_month_leap[month] : days_in_month[month];
96
97 /* printf( "I Y%d M%d %d %d %d %d\n", year, month, *y, *m, *d, days); */
98
99 *d += days;
100 (*m)--;
101 }
102 } else {
103 while (*d < 0) {
104 leapyear = timelib_is_leap(year);
105 days = leapyear ? days_in_month_leap[month] : days_in_month[month];
106
107 /* printf( "I Y%d M%d %d %d %d %d\n", year, month, *y, *m, *d, days); */
108
109 *d += days;
110 (*m)--;
111 inc_month(&year, &month);
112 }
113 }
114 /*
115 printf( "E: Y%d M%d %d %d %d %d\n", year, month, *y, *m, *d, days);
116 */
117 }
118
do_range_limit_days(timelib_sll * y,timelib_sll * m,timelib_sll * d)119 static int do_range_limit_days(timelib_sll *y, timelib_sll *m, timelib_sll *d)
120 {
121 timelib_sll leapyear;
122 timelib_sll days_this_month;
123 timelib_sll last_month, last_year;
124 timelib_sll days_last_month;
125
126 /* can jump an entire leap year period quickly */
127 if (*d >= DAYS_PER_LYEAR_PERIOD || *d <= -DAYS_PER_LYEAR_PERIOD) {
128 *y += YEARS_PER_LYEAR_PERIOD * (*d / DAYS_PER_LYEAR_PERIOD);
129 *d -= DAYS_PER_LYEAR_PERIOD * (*d / DAYS_PER_LYEAR_PERIOD);
130 }
131
132 do_range_limit(1, 13, 12, m, y);
133
134 leapyear = timelib_is_leap(*y);
135 days_this_month = leapyear ? days_in_month_leap[*m] : days_in_month[*m];
136 last_month = (*m) - 1;
137
138 if (last_month < 1) {
139 last_month += 12;
140 last_year = (*y) - 1;
141 } else {
142 last_year = (*y);
143 }
144 leapyear = timelib_is_leap(last_year);
145 days_last_month = leapyear ? days_in_month_leap[last_month] : days_in_month[last_month];
146
147 if (*d <= 0) {
148 *d += days_last_month;
149 (*m)--;
150 return 1;
151 }
152 if (*d > days_this_month) {
153 *d -= days_this_month;
154 (*m)++;
155 return 1;
156 }
157 return 0;
158 }
159
do_adjust_for_weekday(timelib_time * time)160 static void do_adjust_for_weekday(timelib_time* time)
161 {
162 timelib_sll current_dow, difference;
163
164 current_dow = timelib_day_of_week(time->y, time->m, time->d);
165 if (time->relative.weekday_behavior == 2)
166 {
167 /* To make "this week" work, where the current DOW is a "sunday" */
168 if (current_dow == 0 && time->relative.weekday != 0) {
169 time->relative.weekday -= 7;
170 }
171
172 /* To make "sunday this week" work, where the current DOW is not a
173 * "sunday" */
174 if (time->relative.weekday == 0 && current_dow != 0) {
175 time->relative.weekday = 7;
176 }
177
178 time->d -= current_dow;
179 time->d += time->relative.weekday;
180 return;
181 }
182 difference = time->relative.weekday - current_dow;
183 if ((time->relative.d < 0 && difference < 0) || (time->relative.d >= 0 && difference <= -time->relative.weekday_behavior)) {
184 difference += 7;
185 }
186 if (time->relative.weekday >= 0) {
187 time->d += difference;
188 } else {
189 time->d -= (7 - (abs(time->relative.weekday) - current_dow));
190 }
191 time->relative.have_weekday_relative = 0;
192 }
193
timelib_do_rel_normalize(timelib_time * base,timelib_rel_time * rt)194 void timelib_do_rel_normalize(timelib_time *base, timelib_rel_time *rt)
195 {
196 do_range_limit(0, 60, 60, &rt->s, &rt->i);
197 do_range_limit(0, 60, 60, &rt->i, &rt->h);
198 do_range_limit(0, 24, 24, &rt->h, &rt->d);
199 do_range_limit(0, 12, 12, &rt->m, &rt->y);
200
201 do_range_limit_days_relative(&base->y, &base->m, &rt->y, &rt->m, &rt->d, rt->invert);
202 do_range_limit(0, 12, 12, &rt->m, &rt->y);
203 }
204
timelib_do_normalize(timelib_time * time)205 void timelib_do_normalize(timelib_time* time)
206 {
207 if (time->f != TIMELIB_UNSET) do_range_limit_fraction(&time->f, &time->s);
208 if (time->s != TIMELIB_UNSET) do_range_limit(0, 60, 60, &time->s, &time->i);
209 if (time->s != TIMELIB_UNSET) do_range_limit(0, 60, 60, &time->i, &time->h);
210 if (time->s != TIMELIB_UNSET) do_range_limit(0, 24, 24, &time->h, &time->d);
211 do_range_limit(1, 13, 12, &time->m, &time->y);
212
213 do {} while (do_range_limit_days(&time->y, &time->m, &time->d));
214 do_range_limit(1, 13, 12, &time->m, &time->y);
215 }
216
do_adjust_relative(timelib_time * time)217 static void do_adjust_relative(timelib_time* time)
218 {
219 if (time->relative.have_weekday_relative) {
220 do_adjust_for_weekday(time);
221 }
222 timelib_do_normalize(time);
223
224 if (time->have_relative) {
225 time->f += time->relative.f;
226
227 time->s += time->relative.s;
228 time->i += time->relative.i;
229 time->h += time->relative.h;
230
231 time->d += time->relative.d;
232 time->m += time->relative.m;
233 time->y += time->relative.y;
234 }
235
236 switch (time->relative.first_last_day_of) {
237 case TIMELIB_SPECIAL_FIRST_DAY_OF_MONTH: /* first */
238 time->d = 1;
239 break;
240 case TIMELIB_SPECIAL_LAST_DAY_OF_MONTH: /* last */
241 time->d = 0;
242 time->m++;
243 break;
244 }
245
246 timelib_do_normalize(time);
247 }
248
do_adjust_special_weekday(timelib_time * time)249 static void do_adjust_special_weekday(timelib_time* time)
250 {
251 timelib_sll count, dow, rem;
252
253 count = time->relative.special.amount;
254 dow = timelib_day_of_week(time->y, time->m, time->d);
255
256 /* Add increments of 5 weekdays as a week, leaving the DOW unchanged. */
257 time->d += (count / 5) * 7;
258
259 /* Deal with the remainder. */
260 rem = (count % 5);
261
262 if (count > 0) {
263 if (rem == 0) {
264 /* Head back to Friday if we stop on the weekend. */
265 if (dow == 0) {
266 time->d -= 2;
267 } else if (dow == 6) {
268 time->d -= 1;
269 }
270 } else if (dow == 6) {
271 /* We ended up on Saturday, but there's still work to do, so move
272 * to Sunday and continue from there. */
273 time->d += 1;
274 } else if (dow + rem > 5) {
275 /* We're on a weekday, but we're going past Friday, so skip right
276 * over the weekend. */
277 time->d += 2;
278 }
279 } else {
280 /* Completely mirror the forward direction. This also covers the 0
281 * case, since if we start on the weekend, we want to move forward as
282 * if we stopped there while going backwards. */
283 if (rem == 0) {
284 if (dow == 6) {
285 time->d += 2;
286 } else if (dow == 0) {
287 time->d += 1;
288 }
289 } else if (dow == 0) {
290 time->d -= 1;
291 } else if (dow + rem < 1) {
292 time->d -= 2;
293 }
294 }
295
296 time->d += rem;
297 }
298
do_adjust_special(timelib_time * time)299 static void do_adjust_special(timelib_time* time)
300 {
301 if (time->relative.have_special_relative) {
302 switch (time->relative.special.type) {
303 case TIMELIB_SPECIAL_WEEKDAY:
304 do_adjust_special_weekday(time);
305 break;
306 }
307 }
308 timelib_do_normalize(time);
309 memset(&(time->relative.special), 0, sizeof(time->relative.special));
310 }
311
do_adjust_special_early(timelib_time * time)312 static void do_adjust_special_early(timelib_time* time)
313 {
314 if (time->relative.have_special_relative) {
315 switch (time->relative.special.type) {
316 case TIMELIB_SPECIAL_DAY_OF_WEEK_IN_MONTH:
317 time->d = 1;
318 time->m += time->relative.m;
319 time->relative.m = 0;
320 break;
321 case TIMELIB_SPECIAL_LAST_DAY_OF_WEEK_IN_MONTH:
322 time->d = 1;
323 time->m += time->relative.m + 1;
324 time->relative.m = 0;
325 break;
326 }
327 }
328 switch (time->relative.first_last_day_of) {
329 case TIMELIB_SPECIAL_FIRST_DAY_OF_MONTH: /* first */
330 time->d = 1;
331 break;
332 case TIMELIB_SPECIAL_LAST_DAY_OF_MONTH: /* last */
333 time->d = 0;
334 time->m++;
335 break;
336 }
337 timelib_do_normalize(time);
338 }
339
do_years(timelib_sll year)340 static timelib_sll do_years(timelib_sll year)
341 {
342 timelib_sll i;
343 timelib_sll res = 0;
344 timelib_sll eras;
345
346 eras = (year - 1970) / 40000;
347 if (eras != 0) {
348 year = year - (eras * 40000);
349 res += (SECS_PER_ERA * eras * 100);
350 }
351
352 if (year >= 1970) {
353 for (i = year - 1; i >= 1970; i--) {
354 if (timelib_is_leap(i)) {
355 res += (DAYS_PER_LYEAR * SECS_PER_DAY);
356 } else {
357 res += (DAYS_PER_YEAR * SECS_PER_DAY);
358 }
359 }
360 } else {
361 for (i = 1969; i >= year; i--) {
362 if (timelib_is_leap(i)) {
363 res -= (DAYS_PER_LYEAR * SECS_PER_DAY);
364 } else {
365 res -= (DAYS_PER_YEAR * SECS_PER_DAY);
366 }
367 }
368 }
369 return res;
370 }
371
do_months(timelib_ull month,timelib_sll year)372 static timelib_sll do_months(timelib_ull month, timelib_sll year)
373 {
374 if (timelib_is_leap(year)) {
375 return ((month_tab_leap[month - 1] + 1) * SECS_PER_DAY);
376 } else {
377 return ((month_tab[month - 1]) * SECS_PER_DAY);
378 }
379 }
380
do_days(timelib_ull day)381 static timelib_sll do_days(timelib_ull day)
382 {
383 return ((day - 1) * SECS_PER_DAY);
384 }
385
do_time(timelib_ull hour,timelib_ull minute,timelib_ull second)386 static timelib_sll do_time(timelib_ull hour, timelib_ull minute, timelib_ull second)
387 {
388 timelib_sll res = 0;
389
390 res += hour * 3600;
391 res += minute * 60;
392 res += second;
393 return res;
394 }
395
do_adjust_timezone(timelib_time * tz,timelib_tzinfo * tzi)396 static timelib_sll do_adjust_timezone(timelib_time *tz, timelib_tzinfo *tzi)
397 {
398 switch (tz->zone_type) {
399 case TIMELIB_ZONETYPE_OFFSET:
400
401 tz->is_localtime = 1;
402 return tz->z * 60;
403 break;
404
405 case TIMELIB_ZONETYPE_ABBR: {
406 timelib_sll tmp;
407
408 tz->is_localtime = 1;
409 tmp = tz->z;
410 tmp -= tz->dst * 60;
411 tmp *= 60;
412 return tmp;
413 }
414 break;
415
416 case TIMELIB_ZONETYPE_ID:
417 tzi = tz->tz_info;
418 /* Break intentionally missing */
419
420 default:
421 /* No timezone in struct, fallback to reference if possible */
422 if (tzi) {
423 timelib_time_offset *before, *after;
424 timelib_sll tmp;
425 int in_transistion;
426
427 tz->is_localtime = 1;
428 before = timelib_get_time_zone_info(tz->sse, tzi);
429 after = timelib_get_time_zone_info(tz->sse - before->offset, tzi);
430 timelib_set_timezone(tz, tzi);
431
432 in_transistion = (
433 ((tz->sse - after->offset) >= (after->transistion_time + (before->offset - after->offset))) &&
434 ((tz->sse - after->offset) < after->transistion_time)
435 );
436
437 if ((before->offset != after->offset) && !in_transistion) {
438 tmp = -after->offset;
439 } else {
440 tmp = -tz->z;
441 }
442 timelib_time_offset_dtor(before);
443 timelib_time_offset_dtor(after);
444
445 {
446 timelib_time_offset *gmt_offset;
447
448 gmt_offset = timelib_get_time_zone_info(tz->sse + tmp, tzi);
449 tz->z = gmt_offset->offset;
450
451 tz->dst = gmt_offset->is_dst;
452 if (tz->tz_abbr) {
453 timelib_free(tz->tz_abbr);
454 }
455 tz->tz_abbr = timelib_strdup(gmt_offset->abbr);
456 timelib_time_offset_dtor(gmt_offset);
457 }
458 return tmp;
459 }
460 }
461 return 0;
462 }
463
timelib_update_ts(timelib_time * time,timelib_tzinfo * tzi)464 void timelib_update_ts(timelib_time* time, timelib_tzinfo* tzi)
465 {
466 timelib_sll res = 0;
467
468 do_adjust_special_early(time);
469 do_adjust_relative(time);
470 do_adjust_special(time);
471 res += do_years(time->y);
472 res += do_months(time->m, time->y);
473 res += do_days(time->d);
474 res += do_time(time->h, time->i, time->s);
475 time->sse = res;
476
477 res += do_adjust_timezone(time, tzi);
478 time->sse = res;
479
480 time->sse_uptodate = 1;
481 time->have_relative = time->relative.have_weekday_relative = time->relative.have_special_relative = time->relative.first_last_day_of = 0;
482 }
483
484 #if 0
485 int main(void)
486 {
487 timelib_sll res;
488 timelib_time time;
489
490 time = timelib_strtotime("10 Feb 2005 06:07:03 PM CET"); /* 1108055223 */
491 printf ("%04d-%02d-%02d %02d:%02d:%02d.%-5d %+04d %1d",
492 time.y, time.m, time.d, time.h, time.i, time.s, time.f, time.z, time.dst);
493 if (time.have_relative) {
494 printf ("%3dY %3dM %3dD / %3dH %3dM %3dS",
495 time.relative.y, time.relative.m, time.relative.d, time.relative.h, time.relative.i, time.relative.s);
496 }
497 if (time.have_weekday_relative) {
498 printf (" / %d", time.relative.weekday);
499 }
500 res = time2unixtime(&time);
501 printf("%Ld\n", res);
502
503 return 0;
504 }
505 #endif
506
