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a272e669
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1/*
2
3Copyright (c) 2007-2008 Michael G Schwern
4
5This software originally derived from Paul Sheer's pivotal_gmtime_r.c.
6
7The MIT License:
8
9Permission is hereby granted, free of charge, to any person obtaining a copy
10of this software and associated documentation files (the "Software"), to deal
11in the Software without restriction, including without limitation the rights
12to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13copies of the Software, and to permit persons to whom the Software is
14furnished to do so, subject to the following conditions:
15
16The above copyright notice and this permission notice shall be included in
17all copies or substantial portions of the Software.
18
19THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25THE SOFTWARE.
26
27*/
28
29/*
30
31Programmers who have available to them 64-bit time values as a 'long
32long' type can use localtime64_r() and gmtime64_r() which correctly
33converts the time even on 32-bit systems. Whether you have 64-bit time
34values will depend on the operating system.
35
f832b29a 36Perl_localtime64_r() is a 64-bit equivalent of localtime_r().
a272e669 37
f832b29a 38Perl_gmtime64_r() is a 64-bit equivalent of gmtime_r().
a272e669
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39
40*/
41
f832b29a
JH
42#include "EXTERN.h"
43#define PERL_IN_TIME64_C
44#include "perl.h"
7643e68f 45#include "time64.h"
af9b2bf5 46
4bb2f1fc 47static const char days_in_month[2][12] = {
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48 {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
49 {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
50};
51
4bb2f1fc 52static const short julian_days_by_month[2][12] = {
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53 {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334},
54 {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335},
55};
56
4bb2f1fc 57static const short length_of_year[2] = { 365, 366 };
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58
59/* Number of days in a 400 year Gregorian cycle */
806a119a 60static const Year years_in_gregorian_cycle = 400;
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61static const int days_in_gregorian_cycle = (365 * 400) + 100 - 4 + 1;
62
63/* 28 year calendar cycle between 2010 and 2037 */
806a119a 64#define SOLAR_CYCLE_LENGTH 28
4bb2f1fc 65static const short safe_years[SOLAR_CYCLE_LENGTH] = {
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66 2016, 2017, 2018, 2019,
67 2020, 2021, 2022, 2023,
68 2024, 2025, 2026, 2027,
69 2028, 2029, 2030, 2031,
70 2032, 2033, 2034, 2035,
71 2036, 2037, 2010, 2011,
72 2012, 2013, 2014, 2015
73};
74
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MS
75/* Let's assume people are going to be looking for dates in the future.
76 Let's provide some cheats so you can skip ahead.
77 This has a 4x speed boost when near 2008.
78*/
79/* Number of days since epoch on Jan 1st, 2008 GMT */
80#define CHEAT_DAYS (1199145600 / 24 / 60 / 60)
81#define CHEAT_YEARS 108
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82
83#define IS_LEAP(n) ((!(((n) + 1900) % 400) || (!(((n) + 1900) % 4) && (((n) + 1900) % 100))) != 0)
d584a308 84#undef WRAP /* some <termios.h> define this */
a272e669
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85#define WRAP(a,b,m) ((a) = ((a) < 0 ) ? ((b)--, (a) + (m)) : (a))
86
b86b480f
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87#ifdef USE_SYSTEM_LOCALTIME
88# define SHOULD_USE_SYSTEM_LOCALTIME(a) ( \
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89 (a) <= SYSTEM_LOCALTIME_MAX && \
90 (a) >= SYSTEM_LOCALTIME_MIN \
91)
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92#else
93# define SHOULD_USE_SYSTEM_LOCALTIME(a) (0)
94#endif
95
96#ifdef USE_SYSTEM_GMTIME
97# define SHOULD_USE_SYSTEM_GMTIME(a) ( \
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98 (a) <= SYSTEM_GMTIME_MAX && \
99 (a) >= SYSTEM_GMTIME_MIN \
100)
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101#else
102# define SHOULD_USE_SYSTEM_GMTIME(a) (0)
103#endif
a64acb40 104
d4fb0a1f 105/* Multi varadic macros are a C99 thing, alas */
461d5a49 106#ifdef TIME_64_DEBUG
7430375d
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107# define TIME64_TRACE(format) (fprintf(stderr, format))
108# define TIME64_TRACE1(format, var1) (fprintf(stderr, format, var1))
109# define TIME64_TRACE2(format, var1, var2) (fprintf(stderr, format, var1, var2))
110# define TIME64_TRACE3(format, var1, var2, var3) (fprintf(stderr, format, var1, var2, var3))
461d5a49 111#else
7430375d
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112# define TIME64_TRACE(format) ((void)0)
113# define TIME64_TRACE1(format, var1) ((void)0)
114# define TIME64_TRACE2(format, var1, var2) ((void)0)
115# define TIME64_TRACE3(format, var1, var2, var3) ((void)0)
461d5a49 116#endif
a64acb40 117
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118/* Set up the mutexes for this file. There are no races possible on
119 * non-threaded perls, nor platforms that naturally don't have them.
120 * Otherwise, we need to have mutexes. If we have reentrant versions of the
121 * functions below, they automatically will be substituted for the
122 * non-reentrant ones. That solves the problem of the buffers being trashed by
123 * another thread, but not of the environment or locale changing during their
124 * execution. To do that, we only need a read lock (which prevents writing by
125 * others). However, if we don't have re-entrant functions, we can gain some
126 * measure of thread-safety by using an exclusive lock during their execution.
127 * That will protect against any other use of the functions that use the
128 * mutexes, which all of core should be using. */
129#ifdef USE_REENTRANT_API /* This indicates a platform where we need reentrant
130 versions if have them */
131# ifdef PERL_REENTR_USING_LOCALTIME_R
132# define LOCALTIME_LOCK ENV_LOCALE_READ_LOCK
133# define LOCALTIME_UNLOCK ENV_LOCALE_READ_UNLOCK
134# else
135# define LOCALTIME_LOCK ENV_LOCALE_LOCK
136# define LOCALTIME_UNLOCK ENV_LOCALE_UNLOCK
137# endif
138# ifdef PERL_REENTR_USING_GMTIME_R
139# define GMTIME_LOCK ENV_LOCALE_READ_LOCK
140# define GMTIME_UNLOCK ENV_LOCALE_READ_UNLOCK
141# else
142# define GMTIME_LOCK ENV_LOCALE_LOCK
143# define GMTIME_UNLOCK ENV_LOCALE_UNLOCK
144# endif
145#else /* Reentrant not needed, so races not possible */
146# define LOCALTIME_LOCK NOOP
147# define LOCALTIME_UNLOCK NOOP
148# define GMTIME_LOCK NOOP
149# define GMTIME_UNLOCK NOOP
150#endif
151
7430375d 152static int S_is_exception_century(Year year)
a272e669 153{
c75442a5 154 const int is_exception = ((year % 100 == 0) && !(year % 400 == 0));
7430375d 155 TIME64_TRACE1("# is_exception_century: %s\n", is_exception ? "yes" : "no");
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156
157 return(is_exception);
158}
159
9af24521 160
c75442a5 161static Time64_T S_timegm64(const struct TM *date) {
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162 int days = 0;
163 Time64_T seconds = 0;
a272e669 164
9af24521 165 if( date->tm_year > 70 ) {
c75442a5 166 Year year = 70;
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167 while( year < date->tm_year ) {
168 days += length_of_year[IS_LEAP(year)];
169 year++;
a272e669
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170 }
171 }
9af24521 172 else if ( date->tm_year < 70 ) {
c75442a5 173 Year year = 69;
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174 do {
175 days -= length_of_year[IS_LEAP(year)];
176 year--;
177 } while( year >= date->tm_year );
178 }
179
180 days += julian_days_by_month[IS_LEAP(date->tm_year)][date->tm_mon];
181 days += date->tm_mday - 1;
182
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183 /* Avoid overflowing the days integer */
184 seconds = days;
185 seconds = seconds * 60 * 60 * 24;
186
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187 seconds += date->tm_hour * 60 * 60;
188 seconds += date->tm_min * 60;
189 seconds += date->tm_sec;
190
b86b480f 191 return(seconds);
9af24521
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192}
193
194
554fcfb9 195#ifdef DEBUGGING
c75442a5 196static int S_check_tm(const struct TM *tm)
9af24521 197{
9af24521 198 /* Don't forget leap seconds */
af9b2bf5 199 assert(tm->tm_sec >= 0);
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200 assert(tm->tm_sec <= 61);
201
af9b2bf5 202 assert(tm->tm_min >= 0);
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203 assert(tm->tm_min <= 59);
204
205 assert(tm->tm_hour >= 0);
206 assert(tm->tm_hour <= 23);
207
208 assert(tm->tm_mday >= 1);
af9b2bf5 209 assert(tm->tm_mday <= days_in_month[IS_LEAP(tm->tm_year)][tm->tm_mon]);
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210
211 assert(tm->tm_mon >= 0);
212 assert(tm->tm_mon <= 11);
213
214 assert(tm->tm_wday >= 0);
215 assert(tm->tm_wday <= 6);
216
217 assert(tm->tm_yday >= 0);
af9b2bf5 218 assert(tm->tm_yday <= length_of_year[IS_LEAP(tm->tm_year)]);
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219
220#ifdef HAS_TM_TM_GMTOFF
221 assert(tm->tm_gmtoff >= -24 * 60 * 60);
222 assert(tm->tm_gmtoff <= 24 * 60 * 60);
223#endif
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224
225 return 1;
a272e669 226}
554fcfb9 227#endif
a64acb40 228
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229
230/* The exceptional centuries without leap years cause the cycle to
231 shift by 16
232*/
7430375d 233static Year S_cycle_offset(Year year)
a272e669 234{
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235 const Year start_year = 2000;
236 Year year_diff = year - start_year;
237 Year exceptions;
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238
239 if( year > start_year )
240 year_diff--;
241
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242 exceptions = year_diff / 100;
243 exceptions -= year_diff / 400;
a272e669 244
7430375d 245 TIME64_TRACE3("# year: %lld, exceptions: %lld, year_diff: %lld\n",
461d5a49 246 year, exceptions, year_diff);
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247
248 return exceptions * 16;
249}
250
251/* For a given year after 2038, pick the latest possible matching
252 year in the 28 year calendar cycle.
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253
254 A matching year...
255 1) Starts on the same day of the week.
256 2) Has the same leap year status.
257
258 This is so the calendars match up.
259
260 Also the previous year must match. When doing Jan 1st you might
261 wind up on Dec 31st the previous year when doing a -UTC time zone.
003c3b95
MS
262
263 Finally, the next year must have the same start day of week. This
264 is for Dec 31st with a +UTC time zone.
265 It doesn't need the same leap year status since we only care about
266 January 1st.
a272e669 267*/
7430375d 268static int S_safe_year(Year year)
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269{
270 int safe_year;
7430375d 271 Year year_cycle = year + S_cycle_offset(year);
a272e669
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272
273 /* Change non-leap xx00 years to an equivalent */
7430375d 274 if( S_is_exception_century(year) )
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275 year_cycle += 11;
276
003c3b95 277 /* Also xx01 years, since the previous year will be wrong */
7430375d 278 if( S_is_exception_century(year - 1) )
003c3b95
MS
279 year_cycle += 17;
280
a272e669 281 year_cycle %= SOLAR_CYCLE_LENGTH;
ea722b76
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282 if( year_cycle < 0 )
283 year_cycle = SOLAR_CYCLE_LENGTH + year_cycle;
a272e669 284
003c3b95
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285 assert( year_cycle >= 0 );
286 assert( year_cycle < SOLAR_CYCLE_LENGTH );
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287 safe_year = safe_years[year_cycle];
288
289 assert(safe_year <= 2037 && safe_year >= 2010);
290
7430375d 291 TIME64_TRACE3("# year: %lld, year_cycle: %lld, safe_year: %d\n",
461d5a49 292 year, year_cycle, safe_year);
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293
294 return safe_year;
295}
296
750c447b 297
7430375d 298static void S_copy_little_tm_to_big_TM(const struct tm *src, struct TM *dest) {
606599e1
AD
299 assert(src);
300 assert(dest);
55971e21
DD
301#ifdef USE_TM64
302 dest->tm_sec = src->tm_sec;
303 dest->tm_min = src->tm_min;
304 dest->tm_hour = src->tm_hour;
305 dest->tm_mday = src->tm_mday;
306 dest->tm_mon = src->tm_mon;
307 dest->tm_year = (Year)src->tm_year;
308 dest->tm_wday = src->tm_wday;
309 dest->tm_yday = src->tm_yday;
310 dest->tm_isdst = src->tm_isdst;
311
312# ifdef HAS_TM_TM_GMTOFF
313 dest->tm_gmtoff = src->tm_gmtoff;
314# endif
315
316# ifdef HAS_TM_TM_ZONE
317 dest->tm_zone = src->tm_zone;
318# endif
319
320#else
321 /* They're the same type */
322 memcpy(dest, src, sizeof(*dest));
323#endif
806a119a
MS
324}
325
f832b29a 326struct TM *Perl_gmtime64_r (const Time64_T *in_time, struct TM *p)
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327{
328 int v_tm_sec, v_tm_min, v_tm_hour, v_tm_mon, v_tm_wday;
b86b480f 329 Time64_T v_tm_tday;
a272e669 330 int leap;
b86b480f 331 Time64_T m;
a272e669 332 Time64_T time = *in_time;
750c447b 333 Year year = 70;
315d3362 334 dTHX;
a272e669 335
948ea7a9
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336 assert(p != NULL);
337
a64acb40
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338 /* Use the system gmtime() if time_t is small enough */
339 if( SHOULD_USE_SYSTEM_GMTIME(*in_time) ) {
cd1759d8 340 time_t safe_time = (time_t)*in_time;
806a119a 341 struct tm safe_date;
315d3362
KW
342 struct tm * result;
343
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344 GMTIME_LOCK;
345
315d3362
KW
346 /* reentr.h will automatically replace this with a call to gmtime_r()
347 * when appropriate */
348 result = gmtime(&safe_time);
349
350 assert(result != NULL);
351
352#if defined(HAS_GMTIME_R) && defined(USE_REENTRANT_API)
353
354 PERL_UNUSED_VAR(safe_date);
355#else
356 /* Here, no gmtime_r() and is a threaded perl where the result can be
357 * overwritten by a call in another thread. Copy to a safe place,
0e72ccea
KW
358 * hopefully before another gmtime that isn't using the mutexes can
359 * jump in and trash this result. */
315d3362
KW
360 memcpy(&safe_date, result, sizeof(safe_date));
361 result = &safe_date;
362#endif
0e72ccea 363 GMTIME_UNLOCK;
806a119a 364
315d3362 365 S_copy_little_tm_to_big_TM(result, p);
7430375d 366 assert(S_check_tm(p));
806a119a 367
a64acb40
MS
368 return p;
369 }
370
9af24521 371#ifdef HAS_TM_TM_GMTOFF
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372 p->tm_gmtoff = 0;
373#endif
374 p->tm_isdst = 0;
375
9af24521 376#ifdef HAS_TM_TM_ZONE
926c3ce3 377 p->tm_zone = "UTC";
a272e669
MS
378#endif
379
42033175
JH
380 v_tm_sec = (int)Perl_fmod(time, 60.0);
381 time = time >= 0 ? Perl_floor(time / 60.0) : Perl_ceil(time / 60.0);
382 v_tm_min = (int)Perl_fmod(time, 60.0);
383 time = time >= 0 ? Perl_floor(time / 60.0) : Perl_ceil(time / 60.0);
384 v_tm_hour = (int)Perl_fmod(time, 24.0);
385 time = time >= 0 ? Perl_floor(time / 24.0) : Perl_ceil(time / 24.0);
455f2c6c 386 v_tm_tday = time;
750c447b 387
a272e669
MS
388 WRAP (v_tm_sec, v_tm_min, 60);
389 WRAP (v_tm_min, v_tm_hour, 60);
390 WRAP (v_tm_hour, v_tm_tday, 24);
750c447b 391
42033175 392 v_tm_wday = (int)Perl_fmod((v_tm_tday + 4.0), 7.0);
750c447b 393 if (v_tm_wday < 0)
a272e669
MS
394 v_tm_wday += 7;
395 m = v_tm_tday;
a272e669 396
9af24521
MS
397 if (m >= CHEAT_DAYS) {
398 year = CHEAT_YEARS;
399 m -= CHEAT_DAYS;
400 }
401
402 if (m >= 0) {
a272e669 403 /* Gregorian cycles, this is huge optimization for distant times */
c75442a5 404 const int cycles = (int)Perl_floor(m / (Time64_T) days_in_gregorian_cycle);
806a119a
MS
405 if( cycles ) {
406 m -= (cycles * (Time64_T) days_in_gregorian_cycle);
407 year += (cycles * years_in_gregorian_cycle);
a272e669
MS
408 }
409
410 /* Years */
411 leap = IS_LEAP (year);
412 while (m >= (Time64_T) length_of_year[leap]) {
413 m -= (Time64_T) length_of_year[leap];
414 year++;
415 leap = IS_LEAP (year);
416 }
417
418 /* Months */
419 v_tm_mon = 0;
420 while (m >= (Time64_T) days_in_month[leap][v_tm_mon]) {
421 m -= (Time64_T) days_in_month[leap][v_tm_mon];
422 v_tm_mon++;
423 }
424 } else {
c75442a5
AL
425 int cycles;
426
9af24521 427 year--;
a272e669
MS
428
429 /* Gregorian cycles */
42033175 430 cycles = (int)Perl_ceil((m / (Time64_T) days_in_gregorian_cycle) + 1);
806a119a
MS
431 if( cycles ) {
432 m -= (cycles * (Time64_T) days_in_gregorian_cycle);
433 year += (cycles * years_in_gregorian_cycle);
a272e669
MS
434 }
435
436 /* Years */
437 leap = IS_LEAP (year);
438 while (m < (Time64_T) -length_of_year[leap]) {
439 m += (Time64_T) length_of_year[leap];
440 year--;
441 leap = IS_LEAP (year);
442 }
443
444 /* Months */
445 v_tm_mon = 11;
446 while (m < (Time64_T) -days_in_month[leap][v_tm_mon]) {
447 m += (Time64_T) days_in_month[leap][v_tm_mon];
448 v_tm_mon--;
449 }
450 m += (Time64_T) days_in_month[leap][v_tm_mon];
451 }
452
453 p->tm_year = year;
454 if( p->tm_year != year ) {
9af24521 455#ifdef EOVERFLOW
a272e669 456 errno = EOVERFLOW;
9af24521 457#endif
a272e669
MS
458 return NULL;
459 }
460
b86b480f 461 /* At this point m is less than a year so casting to an int is safe */
a272e669 462 p->tm_mday = (int) m + 1;
b86b480f
MS
463 p->tm_yday = julian_days_by_month[leap][v_tm_mon] + (int)m;
464 p->tm_sec = v_tm_sec;
465 p->tm_min = v_tm_min;
466 p->tm_hour = v_tm_hour;
467 p->tm_mon = v_tm_mon;
468 p->tm_wday = v_tm_wday;
a272e669 469
7430375d 470 assert(S_check_tm(p));
a272e669
MS
471
472 return p;
473}
474
475
f832b29a 476struct TM *Perl_localtime64_r (const Time64_T *time, struct TM *local_tm)
a272e669
MS
477{
478 time_t safe_time;
806a119a 479 struct tm safe_date;
4684bf2c 480 const struct tm * result;
806a119a 481 struct TM gm_tm;
153764ac 482 Year orig_year = 0; /* initialise to avoid spurious compiler warning */
a272e669 483 int month_diff;
6358af17 484 const bool use_system = SHOULD_USE_SYSTEM_LOCALTIME(*time);
4684bf2c 485 dTHX;
a272e669 486
948ea7a9
MS
487 assert(local_tm != NULL);
488
a64acb40 489 /* Use the system localtime() if time_t is small enough */
6358af17 490 if (use_system) {
cd1759d8 491 safe_time = (time_t)*time;
806a119a 492
7430375d 493 TIME64_TRACE1("Using system localtime for %lld\n", *time);
a64acb40 494 }
0bd9a4dd 495 else {
9b5e0ded
KW
496 if (Perl_gmtime64_r(time, &gm_tm) == NULL) {
497 TIME64_TRACE1("gmtime64_r returned null for %lld\n", *time);
498 return NULL;
499 }
af832814 500
9b5e0ded 501 orig_year = gm_tm.tm_year;
a272e669 502
9b5e0ded
KW
503 if (gm_tm.tm_year > (2037 - 1900) ||
504 gm_tm.tm_year < (1970 - 1900)
505 )
506 {
507 TIME64_TRACE1("Mapping tm_year %lld to safe_year\n",
508 (Year)gm_tm.tm_year);
509 gm_tm.tm_year = S_safe_year((Year)(gm_tm.tm_year + 1900)) - 1900;
510 }
a272e669 511
9b5e0ded 512 safe_time = (time_t)S_timegm64(&gm_tm);
0bd9a4dd
KW
513 }
514
0e72ccea
KW
515 LOCALTIME_LOCK;
516
4684bf2c
KW
517 /* reentr.h will automatically replace this with a call to localtime_r()
518 * when appropriate */
519 result = localtime(&safe_time);
520
06769212 521 if(UNLIKELY(result == NULL)) {
0e72ccea 522 LOCALTIME_UNLOCK;
4684bf2c 523 TIME64_TRACE1("localtime(%d) returned NULL\n", (int)safe_time);
af832814 524 return NULL;
461d5a49 525 }
a272e669 526
4684bf2c
KW
527#if ! defined(USE_REENTRANT_API) || defined(PERL_REENTR_USING_LOCALTIME_R)
528
529 PERL_UNUSED_VAR(safe_date);
530
531#else
532
533 /* Here, would be using localtime_r() if it could, meaning there isn't one,
534 * and is a threaded perl where the result can be overwritten by a call in
535 * another thread. Copy to a safe place, hopefully before another
0e72ccea
KW
536 * localtime that isn't using the mutexes can jump in and trash this
537 * result. */
4684bf2c
KW
538 memcpy(&safe_date, result, sizeof(safe_date));
539 result = &safe_date;
540
541#endif
542
0e72ccea
KW
543 LOCALTIME_UNLOCK;
544
4684bf2c 545 S_copy_little_tm_to_big_TM(result, local_tm);
806a119a 546
0bd9a4dd
KW
547 if (! use_system) {
548
9b5e0ded
KW
549 local_tm->tm_year = orig_year;
550 if( local_tm->tm_year != orig_year ) {
551 TIME64_TRACE2("tm_year overflow: tm_year %lld, orig_year %lld\n",
552 (Year)local_tm->tm_year, (Year)orig_year);
461d5a49 553
af832814 554#ifdef EOVERFLOW
9b5e0ded 555 errno = EOVERFLOW;
af832814 556#endif
9b5e0ded
KW
557 return NULL;
558 }
af832814 559
9b5e0ded 560 month_diff = local_tm->tm_mon - gm_tm.tm_mon;
a272e669 561
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562 /* When localtime is Dec 31st previous year and
563 gmtime is Jan 1st next year.
564 */
565 if( month_diff == 11 ) {
566 local_tm->tm_year--;
567 }
a272e669 568
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KW
569 /* When localtime is Jan 1st, next year and
570 gmtime is Dec 31st, previous year.
571 */
572 if( month_diff == -11 ) {
573 local_tm->tm_year++;
574 }
a272e669 575
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KW
576 /* GMT is Jan 1st, xx01 year, but localtime is still Dec 31st
577 in a non-leap xx00. There is one point in the cycle
578 we can't account for which the safe xx00 year is a leap
579 year. So we need to correct for Dec 31st coming out as
580 the 366th day of the year.
581 */
582 if( !IS_LEAP(local_tm->tm_year) && local_tm->tm_yday == 365 )
583 local_tm->tm_yday--;
a272e669 584
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KW
585 }
586
7430375d 587 assert(S_check_tm(local_tm));
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MS
588
589 return local_tm;
590}