Line | Count | Source (jump to first uncovered line) |
1 | | /* Convert a 'struct tm' to a time_t value. |
2 | | Copyright (C) 1993-2025 Free Software Foundation, Inc. |
3 | | This file is part of the GNU C Library. |
4 | | Contributed by Paul Eggert <eggert@twinsun.com>. |
5 | | |
6 | | The GNU C Library is free software; you can redistribute it and/or |
7 | | modify it under the terms of the GNU Lesser General Public |
8 | | License as published by the Free Software Foundation; either |
9 | | version 2.1 of the License, or (at your option) any later version. |
10 | | |
11 | | The GNU C Library is distributed in the hope that it will be useful, |
12 | | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | | Lesser General Public License for more details. |
15 | | |
16 | | You should have received a copy of the GNU Lesser General Public |
17 | | License along with the GNU C Library; if not, see |
18 | | <https://www.gnu.org/licenses/>. */ |
19 | | |
20 | | /* The following macros influence what gets defined when this file is compiled: |
21 | | |
22 | | Macro/expression Which gnulib module This compilation unit |
23 | | should define |
24 | | |
25 | | _LIBC (glibc proper) mktime |
26 | | |
27 | | NEED_MKTIME_WORKING mktime rpl_mktime |
28 | | || NEED_MKTIME_WINDOWS |
29 | | |
30 | | NEED_MKTIME_INTERNAL mktime-internal mktime_internal |
31 | | */ |
32 | | |
33 | | #ifndef _LIBC |
34 | | # include <libc-config.h> |
35 | | #endif |
36 | | |
37 | | /* Assume that leap seconds are possible, unless told otherwise. |
38 | | If the host has a 'zic' command with a '-L leapsecondfilename' option, |
39 | | then it supports leap seconds; otherwise it probably doesn't. */ |
40 | | #ifndef LEAP_SECONDS_POSSIBLE |
41 | 0 | # define LEAP_SECONDS_POSSIBLE 1 |
42 | | #endif |
43 | | |
44 | | #include <time.h> |
45 | | |
46 | | #include <errno.h> |
47 | | #include <limits.h> |
48 | | #include <stdbool.h> |
49 | | #include <stdckdint.h> |
50 | | #include <stdlib.h> |
51 | | #include <string.h> |
52 | | |
53 | | #include <intprops.h> |
54 | | |
55 | | #ifndef NEED_MKTIME_INTERNAL |
56 | | # define NEED_MKTIME_INTERNAL 0 |
57 | | #endif |
58 | | #ifndef NEED_MKTIME_WINDOWS |
59 | | # define NEED_MKTIME_WINDOWS 0 |
60 | | #endif |
61 | | #ifndef NEED_MKTIME_WORKING |
62 | | # define NEED_MKTIME_WORKING 0 |
63 | | #endif |
64 | | |
65 | | #ifdef _LIBC |
66 | | # include <tzset.h> |
67 | | #endif |
68 | | #include "mktime-internal.h" |
69 | | |
70 | | #if !defined _LIBC && (NEED_MKTIME_WORKING || NEED_MKTIME_WINDOWS) |
71 | | static void |
72 | | my_tzset (void) |
73 | 0 | { |
74 | | # if NEED_MKTIME_WINDOWS |
75 | | /* Rectify the value of the environment variable TZ. |
76 | | There are four possible kinds of such values: |
77 | | - Traditional US time zone names, e.g. "PST8PDT". Syntax: see |
78 | | <https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/tzset> |
79 | | - Time zone names based on geography, that contain one or more |
80 | | slashes, e.g. "Europe/Moscow". |
81 | | - Time zone names based on geography, without slashes, e.g. |
82 | | "Singapore". |
83 | | - Time zone names that contain explicit DST rules. Syntax: see |
84 | | <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03> |
85 | | The Microsoft CRT understands only the first kind. It produces incorrect |
86 | | results if the value of TZ is of the other kinds. |
87 | | But in a Cygwin environment, /etc/profile.d/tzset.sh sets TZ to a value |
88 | | of the second kind for most geographies, or of the first kind in a few |
89 | | other geographies. If it is of the second kind, neutralize it. For the |
90 | | Microsoft CRT, an absent or empty TZ means the time zone that the user |
91 | | has set in the Windows Control Panel. |
92 | | If the value of TZ is of the third or fourth kind -- Cygwin programs |
93 | | understand these syntaxes as well --, it does not matter whether we |
94 | | neutralize it or not, since these values occur only when a Cygwin user |
95 | | has set TZ explicitly; this case is 1. rare and 2. under the user's |
96 | | responsibility. */ |
97 | | const char *tz = getenv ("TZ"); |
98 | | if (tz != NULL && strchr (tz, '/') != NULL) |
99 | | _putenv ("TZ="); |
100 | | # else |
101 | 0 | tzset (); |
102 | 0 | # endif |
103 | 0 | } |
104 | | # undef tzset |
105 | 0 | # define tzset() my_tzset () |
106 | | #endif |
107 | | |
108 | | #if defined _LIBC || NEED_MKTIME_WORKING || NEED_MKTIME_INTERNAL |
109 | | |
110 | | /* A signed type that can represent an integer number of years |
111 | | multiplied by four times the number of seconds in a year. It is |
112 | | needed when converting a tm_year value times the number of seconds |
113 | | in a year. The factor of four comes because these products need |
114 | | to be subtracted from each other, and sometimes with an offset |
115 | | added to them, and then with another timestamp added, without |
116 | | worrying about overflow. |
117 | | |
118 | | Much of the code uses long_int to represent __time64_t values, to |
119 | | lessen the hassle of dealing with platforms where __time64_t is |
120 | | unsigned, and because long_int should suffice to represent all |
121 | | __time64_t values that mktime can generate even on platforms where |
122 | | __time64_t is wider than the int components of struct tm. */ |
123 | | |
124 | | # if INT_MAX <= LONG_MAX / 4 / 366 / 24 / 60 / 60 |
125 | | typedef long int long_int; |
126 | | # else |
127 | | typedef long long int long_int; |
128 | | # endif |
129 | | static_assert (INT_MAX <= TYPE_MAXIMUM (long_int) / 4 / 366 / 24 / 60 / 60); |
130 | | |
131 | | /* Shift A right by B bits portably, by dividing A by 2**B and |
132 | | truncating towards minus infinity. B should be in the range 0 <= B |
133 | | <= LONG_INT_BITS - 2, where LONG_INT_BITS is the number of useful |
134 | | bits in a long_int. LONG_INT_BITS is at least 32. |
135 | | |
136 | | ISO C99 says that A >> B is implementation-defined if A < 0. Some |
137 | | implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift |
138 | | right in the usual way when A < 0, so SHR falls back on division if |
139 | | ordinary A >> B doesn't seem to be the usual signed shift. */ |
140 | | |
141 | | static long_int |
142 | | shr (long_int a, int b) |
143 | 0 | { |
144 | 0 | long_int one = 1; |
145 | 0 | return (-one >> 1 == -1 |
146 | 0 | ? a >> b |
147 | 0 | : (a + (a < 0)) / (one << b) - (a < 0)); |
148 | 0 | } |
149 | | |
150 | | /* Bounds for the intersection of __time64_t and long_int. */ |
151 | | |
152 | | static long_int const mktime_min |
153 | | = ((TYPE_SIGNED (__time64_t) |
154 | | && TYPE_MINIMUM (__time64_t) < TYPE_MINIMUM (long_int)) |
155 | | ? TYPE_MINIMUM (long_int) : TYPE_MINIMUM (__time64_t)); |
156 | | static long_int const mktime_max |
157 | | = (TYPE_MAXIMUM (long_int) < TYPE_MAXIMUM (__time64_t) |
158 | | ? TYPE_MAXIMUM (long_int) : TYPE_MAXIMUM (__time64_t)); |
159 | | |
160 | 0 | # define EPOCH_YEAR 1970 |
161 | 0 | # define TM_YEAR_BASE 1900 |
162 | | static_assert (TM_YEAR_BASE % 100 == 0); |
163 | | |
164 | | /* Is YEAR + TM_YEAR_BASE a leap year? */ |
165 | | static bool |
166 | | leapyear (long_int year) |
167 | 0 | { |
168 | | /* Don't add YEAR to TM_YEAR_BASE, as that might overflow. |
169 | | Also, work even if YEAR is negative. */ |
170 | 0 | return |
171 | 0 | ((year & 3) == 0 |
172 | 0 | && (year % 100 != 0 |
173 | 0 | || ((year / 100) & 3) == (- (TM_YEAR_BASE / 100) & 3))); |
174 | 0 | } |
175 | | |
176 | | /* How many days come before each month (0-12). */ |
177 | | # ifndef _LIBC |
178 | | static |
179 | | # endif |
180 | | const unsigned short int __mon_yday[2][13] = |
181 | | { |
182 | | /* Normal years. */ |
183 | | { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, |
184 | | /* Leap years. */ |
185 | | { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 } |
186 | | }; |
187 | | |
188 | | |
189 | | /* Do the values A and B differ according to the rules for tm_isdst? |
190 | | A and B differ if one is zero and the other positive. */ |
191 | | static bool |
192 | | isdst_differ (int a, int b) |
193 | 0 | { |
194 | 0 | return (!a != !b) && (0 <= a) && (0 <= b); |
195 | 0 | } |
196 | | |
197 | | /* Return an integer value measuring (YEAR1-YDAY1 HOUR1:MIN1:SEC1) - |
198 | | (YEAR0-YDAY0 HOUR0:MIN0:SEC0) in seconds, assuming that the clocks |
199 | | were not adjusted between the timestamps. |
200 | | |
201 | | The YEAR values uses the same numbering as TP->tm_year. Values |
202 | | need not be in the usual range. However, YEAR1 - YEAR0 must not |
203 | | overflow even when multiplied by three times the number of seconds |
204 | | in a year, and likewise for YDAY1 - YDAY0 and three times the |
205 | | number of seconds in a day. */ |
206 | | |
207 | | static long_int |
208 | | ydhms_diff (long_int year1, long_int yday1, int hour1, int min1, int sec1, |
209 | | int year0, int yday0, int hour0, int min0, int sec0) |
210 | 0 | { |
211 | 0 | static_assert (-1 / 2 == 0); |
212 | | |
213 | | /* Compute intervening leap days correctly even if year is negative. |
214 | | Take care to avoid integer overflow here. */ |
215 | 0 | int a4 = shr (year1, 2) + shr (TM_YEAR_BASE, 2) - ! (year1 & 3); |
216 | 0 | int b4 = shr (year0, 2) + shr (TM_YEAR_BASE, 2) - ! (year0 & 3); |
217 | 0 | int a100 = (a4 + (a4 < 0)) / 25 - (a4 < 0); |
218 | 0 | int b100 = (b4 + (b4 < 0)) / 25 - (b4 < 0); |
219 | 0 | int a400 = shr (a100, 2); |
220 | 0 | int b400 = shr (b100, 2); |
221 | 0 | int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400); |
222 | | |
223 | | /* Compute the desired time without overflowing. */ |
224 | 0 | long_int years = year1 - year0; |
225 | 0 | long_int days = 365 * years + yday1 - yday0 + intervening_leap_days; |
226 | 0 | long_int hours = 24 * days + hour1 - hour0; |
227 | 0 | long_int minutes = 60 * hours + min1 - min0; |
228 | 0 | long_int seconds = 60 * minutes + sec1 - sec0; |
229 | 0 | return seconds; |
230 | 0 | } |
231 | | |
232 | | /* Return the average of A and B, even if A + B would overflow. |
233 | | Round toward positive infinity. */ |
234 | | static long_int |
235 | | long_int_avg (long_int a, long_int b) |
236 | 0 | { |
237 | 0 | return shr (a, 1) + shr (b, 1) + ((a | b) & 1); |
238 | 0 | } |
239 | | |
240 | | /* Return a long_int value corresponding to (YEAR-YDAY HOUR:MIN:SEC) |
241 | | minus *TP seconds, assuming no clock adjustments occurred between |
242 | | the two timestamps. |
243 | | |
244 | | YEAR and YDAY must not be so large that multiplying them by three times the |
245 | | number of seconds in a year (or day, respectively) would overflow long_int. |
246 | | *TP should be in the usual range. */ |
247 | | static long_int |
248 | | tm_diff (long_int year, long_int yday, int hour, int min, int sec, |
249 | | struct tm const *tp) |
250 | 0 | { |
251 | 0 | return ydhms_diff (year, yday, hour, min, sec, |
252 | 0 | tp->tm_year, tp->tm_yday, |
253 | 0 | tp->tm_hour, tp->tm_min, tp->tm_sec); |
254 | 0 | } |
255 | | |
256 | | #ifndef _LIBC |
257 | | /* Convert T to a struct tm value in *TM. Use localtime64_r if LOCAL, |
258 | | otherwise gmtime64_r. T must be in range for __time64_t. Return |
259 | | TM if successful, NULL (setting errno) on failure. */ |
260 | | static struct tm * |
261 | | convert_time (long_int t, bool local, struct tm *tm) |
262 | 0 | { |
263 | 0 | __time64_t x = t; |
264 | 0 | if (local) |
265 | 0 | return __localtime64_r (&x, tm); |
266 | 0 | else |
267 | 0 | return __gmtime64_r (&x, tm); |
268 | 0 | } |
269 | 0 | # define __tz_convert convert_time |
270 | | #endif |
271 | | |
272 | | /* Convert *T to a broken down time in *TP (as if by localtime if |
273 | | LOCAL, otherwise as if by gmtime). If *T is out of range for |
274 | | conversion, adjust it so that it is the nearest in-range value and |
275 | | then convert that. A value is in range if it fits in both |
276 | | __time64_t and long_int. Return TP on success, NULL (setting |
277 | | errno) on failure. */ |
278 | | static struct tm * |
279 | | ranged_convert (bool local, long_int *t, struct tm *tp) |
280 | 0 | { |
281 | 0 | long_int t1 = (*t < mktime_min ? mktime_min |
282 | 0 | : *t <= mktime_max ? *t : mktime_max); |
283 | 0 | struct tm *r = __tz_convert (t1, local, tp); |
284 | 0 | if (r) |
285 | 0 | { |
286 | 0 | *t = t1; |
287 | 0 | return r; |
288 | 0 | } |
289 | 0 | if (errno != EOVERFLOW) |
290 | 0 | return NULL; |
291 | | |
292 | 0 | long_int bad = t1; |
293 | 0 | long_int ok = 0; |
294 | 0 | struct tm oktm; oktm.tm_sec = -1; |
295 | | |
296 | | /* BAD is a known out-of-range value, and OK is a known in-range one. |
297 | | Use binary search to narrow the range between BAD and OK until |
298 | | they differ by 1. */ |
299 | 0 | while (true) |
300 | 0 | { |
301 | 0 | long_int mid = long_int_avg (ok, bad); |
302 | 0 | if (mid == ok || mid == bad) |
303 | 0 | break; |
304 | 0 | if (__tz_convert (mid, local, tp)) |
305 | 0 | ok = mid, oktm = *tp; |
306 | 0 | else if (errno != EOVERFLOW) |
307 | 0 | return NULL; |
308 | 0 | else |
309 | 0 | bad = mid; |
310 | 0 | } |
311 | | |
312 | 0 | if (oktm.tm_sec < 0) |
313 | 0 | return NULL; |
314 | 0 | *t = ok; |
315 | 0 | *tp = oktm; |
316 | 0 | return tp; |
317 | 0 | } |
318 | | |
319 | | |
320 | | /* Convert *TP to a __time64_t value. If LOCAL, the reverse mapping |
321 | | is performed as if localtime, otherwise as if by gmtime. Use |
322 | | *OFFSET to keep track of a guess at the offset of the result, |
323 | | compared to what the result would be for UTC without leap seconds. |
324 | | If *OFFSET's guess is correct, only one reverse mapping call is |
325 | | needed. If successful, set *TP to the canonicalized struct tm; |
326 | | otherwise leave *TP alone, return ((time_t) -1) and set errno. |
327 | | This function is external because it is used also by timegm.c. |
328 | | |
329 | | If _LIBC, the caller must lock __tzset_lock. */ |
330 | | __time64_t |
331 | | __mktime_internal (struct tm *tp, bool local, mktime_offset_t *offset) |
332 | 0 | { |
333 | 0 | struct tm tm; |
334 | | |
335 | | /* The maximum number of probes should be enough to handle any |
336 | | combinations of time zone rule changes, solar time, leap seconds, |
337 | | and oscillations around a spring-forward gap. POSIX.1 prohibits |
338 | | leap seconds, but some hosts have them anyway. */ |
339 | 0 | int remaining_probes = 6; |
340 | |
|
341 | 0 | #ifndef _LIBC |
342 | | /* Gnulib mktime doesn't lock the tz state, so it may need to probe |
343 | | more often if some other thread changes local time while |
344 | | __mktime_internal is probing. Double the number of probes; this |
345 | | should suffice for practical cases that are at all likely. */ |
346 | 0 | remaining_probes *= 2; |
347 | 0 | #endif |
348 | | |
349 | | /* Time requested. Copy it in case gmtime/localtime modify *TP; |
350 | | this can occur if TP is localtime's returned value and CONVERT is |
351 | | localtime. */ |
352 | 0 | int sec = tp->tm_sec; |
353 | 0 | int min = tp->tm_min; |
354 | 0 | int hour = tp->tm_hour; |
355 | 0 | int mday = tp->tm_mday; |
356 | 0 | int mon = tp->tm_mon; |
357 | 0 | int year_requested = tp->tm_year; |
358 | 0 | int isdst = tp->tm_isdst; |
359 | | |
360 | | /* True if the previous probe was DST. */ |
361 | 0 | bool dst2 = false; |
362 | | |
363 | | /* Ensure that mon is in range, and set year accordingly. */ |
364 | 0 | int mon_remainder = mon % 12; |
365 | 0 | int negative_mon_remainder = mon_remainder < 0; |
366 | 0 | int mon_years = mon / 12 - negative_mon_remainder; |
367 | 0 | long_int lyear_requested = year_requested; |
368 | 0 | long_int year = lyear_requested + mon_years; |
369 | | |
370 | | /* The other values need not be in range: |
371 | | the remaining code handles overflows correctly. */ |
372 | | |
373 | | /* Calculate day of year from year, month, and day of month. |
374 | | The result need not be in range. */ |
375 | 0 | int mon_yday = ((__mon_yday[leapyear (year)] |
376 | 0 | [mon_remainder + 12 * negative_mon_remainder]) |
377 | 0 | - 1); |
378 | 0 | long_int lmday = mday; |
379 | 0 | long_int yday = mon_yday + lmday; |
380 | |
|
381 | 0 | mktime_offset_t off = *offset; |
382 | 0 | int negative_offset_guess; |
383 | |
|
384 | 0 | int sec_requested = sec; |
385 | |
|
386 | 0 | if (LEAP_SECONDS_POSSIBLE) |
387 | 0 | { |
388 | | /* Handle out-of-range seconds specially, |
389 | | since ydhms_diff assumes every minute has 60 seconds. */ |
390 | 0 | if (sec < 0) |
391 | 0 | sec = 0; |
392 | 0 | if (59 < sec) |
393 | 0 | sec = 59; |
394 | 0 | } |
395 | | |
396 | | /* Invert CONVERT by probing. First assume the same offset as last |
397 | | time. */ |
398 | |
|
399 | 0 | ckd_sub (&negative_offset_guess, 0, off); |
400 | 0 | long_int t0 = ydhms_diff (year, yday, hour, min, sec, |
401 | 0 | EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, |
402 | 0 | negative_offset_guess); |
403 | 0 | long_int t = t0, t1 = t0, t2 = t0; |
404 | | |
405 | | /* Repeatedly use the error to improve the guess. */ |
406 | |
|
407 | 0 | while (true) |
408 | 0 | { |
409 | 0 | if (! ranged_convert (local, &t, &tm)) |
410 | 0 | return -1; |
411 | 0 | long_int dt = tm_diff (year, yday, hour, min, sec, &tm); |
412 | 0 | if (dt == 0) |
413 | 0 | break; |
414 | | |
415 | 0 | if (t == t1 && t != t2 |
416 | 0 | && (tm.tm_isdst < 0 |
417 | 0 | || (isdst < 0 |
418 | 0 | ? dst2 <= (tm.tm_isdst != 0) |
419 | 0 | : (isdst != 0) != (tm.tm_isdst != 0)))) |
420 | | /* We can't possibly find a match, as we are oscillating |
421 | | between two values. The requested time probably falls |
422 | | within a spring-forward gap of size DT. Follow the common |
423 | | practice in this case, which is to return a time that is DT |
424 | | away from the requested time, preferring a time whose |
425 | | tm_isdst differs from the requested value. (If no tm_isdst |
426 | | was requested and only one of the two values has a nonzero |
427 | | tm_isdst, prefer that value.) In practice, this is more |
428 | | useful than returning -1. */ |
429 | 0 | goto offset_found; |
430 | | |
431 | 0 | remaining_probes--; |
432 | 0 | if (remaining_probes == 0) |
433 | 0 | { |
434 | 0 | __set_errno (EOVERFLOW); |
435 | 0 | return -1; |
436 | 0 | } |
437 | | |
438 | 0 | t1 = t2, t2 = t, t += dt, dst2 = tm.tm_isdst != 0; |
439 | 0 | } |
440 | | |
441 | | /* We have a match. Check whether tm.tm_isdst has the requested |
442 | | value, if any. */ |
443 | 0 | if (isdst_differ (isdst, tm.tm_isdst)) |
444 | 0 | { |
445 | | /* tm.tm_isdst has the wrong value. Look for a neighboring |
446 | | time with the right value, and use its UTC offset. |
447 | | |
448 | | Heuristic: probe the adjacent timestamps in both directions, |
449 | | looking for the desired isdst. If none is found within a |
450 | | reasonable duration bound, ignore the disagreement. |
451 | | This should work for all real time zone histories in the tz |
452 | | database. */ |
453 | | |
454 | | /* Distance between probes when looking for a DST boundary. In |
455 | | tzdata2003a, the shortest period of DST is 601200 seconds |
456 | | (e.g., America/Recife starting 2000-10-08 01:00), and the |
457 | | shortest period of non-DST surrounded by DST is 694800 |
458 | | seconds (Africa/Tunis starting 1943-04-17 01:00). Use the |
459 | | minimum of these two values, so we don't miss these short |
460 | | periods when probing. */ |
461 | 0 | int stride = 601200; |
462 | | |
463 | | /* Do not probe too far away from the requested time, |
464 | | by striding until at least a year has passed, but then giving up. |
465 | | This helps avoid unexpected results in (for example) Asia/Kolkata, |
466 | | for which today's users expect to see no DST even though it |
467 | | did observe DST long ago. */ |
468 | 0 | int year_seconds_bound = 366 * 24 * 60 * 60 + 1; |
469 | 0 | int delta_bound = year_seconds_bound + stride; |
470 | |
|
471 | 0 | int delta, direction; |
472 | | |
473 | | /* Search in both directions, closest first. */ |
474 | 0 | for (delta = stride; delta < delta_bound; delta += stride) |
475 | 0 | for (direction = -1; direction <= 1; direction += 2) |
476 | 0 | { |
477 | 0 | long_int ot; |
478 | 0 | if (! ckd_add (&ot, t, delta * direction)) |
479 | 0 | { |
480 | 0 | struct tm otm; |
481 | 0 | if (! ranged_convert (local, &ot, &otm)) |
482 | 0 | return -1; |
483 | 0 | if (! isdst_differ (isdst, otm.tm_isdst)) |
484 | 0 | { |
485 | | /* We found the desired tm_isdst. |
486 | | Extrapolate back to the desired time. */ |
487 | 0 | long_int gt = ot + tm_diff (year, yday, hour, min, sec, |
488 | 0 | &otm); |
489 | 0 | if (mktime_min <= gt && gt <= mktime_max) |
490 | 0 | { |
491 | 0 | if (__tz_convert (gt, local, &tm)) |
492 | 0 | { |
493 | 0 | t = gt; |
494 | 0 | goto offset_found; |
495 | 0 | } |
496 | 0 | if (errno != EOVERFLOW) |
497 | 0 | return -1; |
498 | 0 | } |
499 | 0 | } |
500 | 0 | } |
501 | 0 | } |
502 | | |
503 | | /* No probe with the requested tm_isdst was found nearby. |
504 | | Ignore the requested tm_isdst. */ |
505 | 0 | } |
506 | | |
507 | 0 | offset_found: |
508 | | /* Set *OFFSET to the low-order bits of T - T0 - NEGATIVE_OFFSET_GUESS. |
509 | | This is just a heuristic to speed up the next mktime call, and |
510 | | correctness is unaffected if integer overflow occurs here. */ |
511 | 0 | ckd_sub (offset, t, t0); |
512 | 0 | ckd_sub (offset, *offset, negative_offset_guess); |
513 | |
|
514 | 0 | if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec) |
515 | 0 | { |
516 | | /* Adjust time to reflect the tm_sec requested, not the normalized value. |
517 | | Also, repair any damage from a false match due to a leap second. */ |
518 | 0 | long_int sec_adjustment = sec == 0 && tm.tm_sec == 60; |
519 | 0 | sec_adjustment -= sec; |
520 | 0 | sec_adjustment += sec_requested; |
521 | 0 | if (ckd_add (&t, t, sec_adjustment) |
522 | 0 | || ! (mktime_min <= t && t <= mktime_max)) |
523 | 0 | { |
524 | 0 | __set_errno (EOVERFLOW); |
525 | 0 | return -1; |
526 | 0 | } |
527 | 0 | if (! __tz_convert (t, local, &tm)) |
528 | 0 | return -1; |
529 | 0 | } |
530 | | |
531 | 0 | *tp = tm; |
532 | 0 | return t; |
533 | 0 | } |
534 | | |
535 | | #endif /* _LIBC || NEED_MKTIME_WORKING || NEED_MKTIME_INTERNAL */ |
536 | | |
537 | | #if defined _LIBC || NEED_MKTIME_WORKING || NEED_MKTIME_WINDOWS |
538 | | |
539 | | /* Convert *TP to a __time64_t value. */ |
540 | | __time64_t |
541 | | __mktime64 (struct tm *tp) |
542 | 0 | { |
543 | 0 | __libc_lock_lock (__tzset_lock); |
544 | 0 | __tzset_unlocked (); |
545 | |
|
546 | 0 | # if defined _LIBC || NEED_MKTIME_WORKING |
547 | 0 | static mktime_offset_t localtime_offset; |
548 | 0 | __time64_t result = __mktime_internal (tp, true, &localtime_offset); |
549 | | # else |
550 | | # undef mktime |
551 | | __time64_t result = mktime (tp); |
552 | | # endif |
553 | |
|
554 | 0 | __libc_lock_unlock (__tzset_lock); |
555 | 0 | return result; |
556 | 0 | } |
557 | | #endif /* _LIBC || NEED_MKTIME_WORKING || NEED_MKTIME_WINDOWS */ |
558 | | |
559 | | #if defined _LIBC && __TIMESIZE != 64 |
560 | | |
561 | | libc_hidden_def (__mktime64) |
562 | | |
563 | | time_t |
564 | | mktime (struct tm *tp) |
565 | | { |
566 | | struct tm tm = *tp; |
567 | | __time64_t t = __mktime64 (&tm); |
568 | | if (in_time_t_range (t)) |
569 | | { |
570 | | *tp = tm; |
571 | | return t; |
572 | | } |
573 | | else |
574 | | { |
575 | | __set_errno (EOVERFLOW); |
576 | | return -1; |
577 | | } |
578 | | } |
579 | | |
580 | | #endif |
581 | | |
582 | | weak_alias (mktime, timelocal) |
583 | | libc_hidden_def (mktime) |
584 | | libc_hidden_weak (timelocal) |