xref: /netbsd-src/lib/libc/time/private.h (revision 3f351f34c6d827cf017cdcff3543f6ec0c88b420)
1 /* Private header for tzdb code.  */
2 
3 /*	$NetBSD: private.h,v 1.67 2023/12/23 20:48:38 christos Exp $	*/
4 
5 #ifndef PRIVATE_H
6 #define PRIVATE_H
7 
8 /* NetBSD defaults */
9 #define TM_GMTOFF	tm_gmtoff
10 #define TM_ZONE		tm_zone
11 #define STD_INSPIRED	1
12 #define HAVE_LONG_DOUBLE 1
13 
14 /* For when we build zic as a host tool. */
15 #if HAVE_NBTOOL_CONFIG_H
16 #include "nbtool_config.h"
17 #endif
18 
19 /*
20 ** This file is in the public domain, so clarified as of
21 ** 1996-06-05 by Arthur David Olson.
22 */
23 
24 /*
25 ** This header is for use ONLY with the time conversion code.
26 ** There is no guarantee that it will remain unchanged,
27 ** or that it will remain at all.
28 ** Do NOT copy it to any system include directory.
29 ** Thank you!
30 */
31 
32 /* PORT_TO_C89 means the code should work even if the underlying
33    compiler and library support only C89 plus C99's 'long long'
34    and perhaps a few other extensions to C89.  SUPPORT_C89 means the
35    tzcode library should support C89 callers in addition to the usual
36    support for C99-and-later callers; however, C89 support can trigger
37    latent bugs in C99-and-later callers.  These macros are obsolescent,
38    and the plan is to remove them along with any code needed only when
39    they are nonzero.  A good time to do that might be in the year 2029
40    because RHEL 7 (whose GCC defaults to C89) extended life cycle
41    support (ELS) is scheduled to end on 2028-06-30.  */
42 #ifndef PORT_TO_C89
43 # define PORT_TO_C89 0
44 #endif
45 #ifndef SUPPORT_C89
46 # define SUPPORT_C89 0
47 #endif
48 
49 #ifndef __STDC_VERSION__
50 # define __STDC_VERSION__ 0
51 #endif
52 
53 /* Define true, false and bool if they don't work out of the box.  */
54 #if PORT_TO_C89 && __STDC_VERSION__ < 199901
55 # define true 1
56 # define false 0
57 # define bool int
58 #elif __STDC_VERSION__ < 202311
59 # include <stdbool.h>
60 #endif
61 
62 #if __STDC_VERSION__ < 202311
63 # define static_assert(cond) extern int static_assert_check[(cond) ? 1 : -1]
64 #endif
65 
66 /*
67 ** zdump has been made independent of the rest of the time
68 ** conversion package to increase confidence in the verification it provides.
69 ** You can use zdump to help in verifying other implementations.
70 ** To do this, compile with -DUSE_LTZ=0 and link without the tz library.
71 */
72 #ifndef USE_LTZ
73 # define USE_LTZ 1
74 #endif
75 
76 /* This string was in the Factory zone through version 2016f.  */
77 #define GRANDPARENTED	"Local time zone must be set--see zic manual page"
78 
79 /*
80 ** Defaults for preprocessor symbols.
81 ** You can override these in your C compiler options, e.g. '-DHAVE_GETTEXT=1'.
82 */
83 
84 #ifndef HAVE_DECL_ASCTIME_R
85 # define HAVE_DECL_ASCTIME_R 1
86 #endif
87 
88 #if !defined HAVE__GENERIC && defined __has_extension
89 # if !__has_extension(c_generic_selections)
90 #  define HAVE__GENERIC 0
91 # endif
92 #endif
93 /* _Generic is buggy in pre-4.9 GCC.  */
94 #if !defined HAVE__GENERIC && defined __GNUC__ && !defined __STRICT_ANSI__
95 # define HAVE__GENERIC (4 < __GNUC__ + (9 <= __GNUC_MINOR__))
96 #endif
97 #ifndef HAVE__GENERIC
98 # define HAVE__GENERIC (201112 <= __STDC_VERSION__)
99 #endif
100 
101 #if !defined HAVE_GETTEXT && defined __has_include
102 # if __has_include(<libintl.h>)
103 #  define HAVE_GETTEXT true
104 # endif
105 #endif
106 #ifndef HAVE_GETTEXT
107 # define HAVE_GETTEXT false
108 #endif
109 
110 #ifndef HAVE_INCOMPATIBLE_CTIME_R
111 # define HAVE_INCOMPATIBLE_CTIME_R 0
112 #endif
113 
114 #ifndef HAVE_LINK
115 # define HAVE_LINK 1
116 #endif /* !defined HAVE_LINK */
117 
118 #ifndef HAVE_MALLOC_ERRNO
119 # define HAVE_MALLOC_ERRNO 1
120 #endif
121 
122 #ifndef HAVE_POSIX_DECLS
123 # define HAVE_POSIX_DECLS 1
124 #endif
125 
126 #ifndef HAVE_SETENV
127 # define HAVE_SETENV 1
128 #endif
129 
130 #ifndef HAVE_STRDUP
131 # define HAVE_STRDUP 1
132 #endif
133 
134 #ifndef HAVE_SYMLINK
135 # define HAVE_SYMLINK 1
136 #endif /* !defined HAVE_SYMLINK */
137 
138 #if !defined HAVE_SYS_STAT_H && defined __has_include
139 # if !__has_include(<sys/stat.h>)
140 #  define HAVE_SYS_STAT_H false
141 # endif
142 #endif
143 #ifndef HAVE_SYS_STAT_H
144 # define HAVE_SYS_STAT_H true
145 #endif
146 
147 #if !defined HAVE_UNISTD_H && defined __has_include
148 # if !__has_include(<unistd.h>)
149 #  define HAVE_UNISTD_H false
150 # endif
151 #endif
152 #ifndef HAVE_UNISTD_H
153 # define HAVE_UNISTD_H true
154 #endif
155 
156 #ifndef NETBSD_INSPIRED
157 # define NETBSD_INSPIRED 1
158 #endif
159 
160 #if HAVE_INCOMPATIBLE_CTIME_R
161 # define asctime_r _incompatible_asctime_r
162 # define ctime_r _incompatible_ctime_r
163 #endif /* HAVE_INCOMPATIBLE_CTIME_R */
164 
165 /* Enable tm_gmtoff, tm_zone, and environ on GNUish systems.  */
166 #define _GNU_SOURCE 1
167 /* Fix asctime_r on Solaris 11.  */
168 #define _POSIX_PTHREAD_SEMANTICS 1
169 /* Enable strtoimax on pre-C99 Solaris 11.  */
170 #define __EXTENSIONS__ 1
171 
172 /* On GNUish systems where time_t might be 32 or 64 bits, use 64.
173    On these platforms _FILE_OFFSET_BITS must also be 64; otherwise
174    setting _TIME_BITS to 64 does not work.  The code does not
175    otherwise rely on _FILE_OFFSET_BITS being 64, since it does not
176    use off_t or functions like 'stat' that depend on off_t.  */
177 #ifndef _FILE_OFFSET_BITS
178 # define _FILE_OFFSET_BITS 64
179 #endif
180 #if !defined _TIME_BITS && _FILE_OFFSET_BITS == 64
181 # define _TIME_BITS 64
182 #endif
183 
184 /*
185 ** Nested includes
186 */
187 
188 #ifndef __NetBSD__
189 /* Avoid clashes with NetBSD by renaming NetBSD's declarations.
190    If defining the 'timezone' variable, avoid a clash with FreeBSD's
191    'timezone' function by renaming its declaration.  */
192 #define localtime_rz sys_localtime_rz
193 #define mktime_z sys_mktime_z
194 #define posix2time_z sys_posix2time_z
195 #define time2posix_z sys_time2posix_z
196 #if defined USG_COMPAT && USG_COMPAT == 2
197 # define timezone sys_timezone
198 #endif
199 #define timezone_t sys_timezone_t
200 #define tzalloc sys_tzalloc
201 #define tzfree sys_tzfree
202 #include <time.h>
203 #undef localtime_rz
204 #undef mktime_z
205 #undef posix2time_z
206 #undef time2posix_z
207 #if defined USG_COMPAT && USG_COMPAT == 2
208 # undef timezone
209 #endif
210 #undef timezone_t
211 #undef tzalloc
212 #undef tzfree
213 #else
214 #include "time.h"
215 #endif
216 
217 #include <stddef.h>
218 #include <string.h>
219 #if !PORT_TO_C89
220 # include <inttypes.h>
221 #endif
222 #include <limits.h>	/* for CHAR_BIT et al. */
223 #include <stdlib.h>
224 
225 #include <errno.h>
226 
227 #ifndef EINVAL
228 # define EINVAL ERANGE
229 #endif
230 
231 #ifndef ELOOP
232 # define ELOOP EINVAL
233 #endif
234 #ifndef ENAMETOOLONG
235 # define ENAMETOOLONG EINVAL
236 #endif
237 #ifndef ENOMEM
238 # define ENOMEM EINVAL
239 #endif
240 #ifndef ENOTSUP
241 # define ENOTSUP EINVAL
242 #endif
243 #ifndef EOVERFLOW
244 # define EOVERFLOW EINVAL
245 #endif
246 
247 #if HAVE_GETTEXT
248 # include <libintl.h>
249 #endif /* HAVE_GETTEXT */
250 
251 #if HAVE_UNISTD_H
252 # include <unistd.h> /* for R_OK, and other POSIX goodness */
253 #endif /* HAVE_UNISTD_H */
254 
255 #ifndef HAVE_STRFTIME_L
256 # if _POSIX_VERSION < 200809
257 #  define HAVE_STRFTIME_L 0
258 # else
259 #  define HAVE_STRFTIME_L 1
260 # endif
261 #endif
262 
263 #ifndef USG_COMPAT
264 # ifndef _XOPEN_VERSION
265 #  define USG_COMPAT 0
266 # else
267 #  define USG_COMPAT 1
268 # endif
269 #endif
270 
271 #ifndef HAVE_TZNAME
272 # if _POSIX_VERSION < 198808 && !USG_COMPAT
273 #  define HAVE_TZNAME 0
274 # else
275 #  define HAVE_TZNAME 1
276 # endif
277 #endif
278 
279 #ifndef ALTZONE
280 # if defined __sun || defined _M_XENIX
281 #  define ALTZONE 1
282 # else
283 #  define ALTZONE 0
284 # endif
285 #endif
286 
287 #ifndef R_OK
288 # define R_OK 4
289 #endif /* !defined R_OK */
290 
291 #if PORT_TO_C89
292 
293 /*
294 ** Define HAVE_STDINT_H's default value here, rather than at the
295 ** start, since __GLIBC__ and INTMAX_MAX's values depend on
296 ** previously included files.  glibc 2.1 and Solaris 10 and later have
297 ** stdint.h, even with pre-C99 compilers.
298 */
299 #if !defined HAVE_STDINT_H && defined __has_include
300 # define HAVE_STDINT_H true /* C23 __has_include implies C99 stdint.h.  */
301 #endif
302 #ifndef HAVE_STDINT_H
303 # define HAVE_STDINT_H \
304    (199901 <= __STDC_VERSION__ \
305     || 2 < __GLIBC__ + (1 <= __GLIBC_MINOR__) \
306     || __CYGWIN__ || INTMAX_MAX)
307 #endif /* !defined HAVE_STDINT_H */
308 
309 #if HAVE_STDINT_H
310 # include <stdint.h>
311 #endif /* !HAVE_STDINT_H */
312 
313 #ifndef HAVE_INTTYPES_H
314 # define HAVE_INTTYPES_H HAVE_STDINT_H
315 #endif
316 #if HAVE_INTTYPES_H
317 # include <inttypes.h>
318 #endif
319 
320 /* Pre-C99 GCC compilers define __LONG_LONG_MAX__ instead of LLONG_MAX.  */
321 #if defined __LONG_LONG_MAX__ && !defined __STRICT_ANSI__
322 # ifndef LLONG_MAX
323 #  define LLONG_MAX __LONG_LONG_MAX__
324 # endif
325 # ifndef LLONG_MIN
326 #  define LLONG_MIN (-1 - LLONG_MAX)
327 # endif
328 # ifndef ULLONG_MAX
329 #  define ULLONG_MAX (LLONG_MAX * 2ull + 1)
330 # endif
331 #endif
332 
333 #ifndef INT_FAST64_MAX
334 # if 1 <= LONG_MAX >> 31 >> 31
335 typedef long int_fast64_t;
336 #  define INT_FAST64_MIN LONG_MIN
337 #  define INT_FAST64_MAX LONG_MAX
338 # else
339 /* If this fails, compile with -DHAVE_STDINT_H or with a better compiler.  */
340 typedef long long int_fast64_t;
341 #  define INT_FAST64_MIN LLONG_MIN
342 #  define INT_FAST64_MAX LLONG_MAX
343 # endif
344 #endif
345 
346 #ifndef PRIdFAST64
347 # if INT_FAST64_MAX == LONG_MAX
348 #  define PRIdFAST64 "ld"
349 # else
350 #  define PRIdFAST64 "lld"
351 # endif
352 #endif
353 
354 #ifndef SCNdFAST64
355 # define SCNdFAST64 PRIdFAST64
356 #endif
357 
358 #ifndef INT_FAST32_MAX
359 # if INT_MAX >> 31 == 0
360 typedef long int_fast32_t;
361 #  define INT_FAST32_MAX LONG_MAX
362 #  define INT_FAST32_MIN LONG_MIN
363 # else
364 typedef int int_fast32_t;
365 #  define INT_FAST32_MAX INT_MAX
366 #  define INT_FAST32_MIN INT_MIN
367 # endif
368 #endif
369 
370 #ifndef INTMAX_MAX
371 # ifdef LLONG_MAX
372 typedef long long intmax_t;
373 #  ifndef HAVE_STRTOLL
374 #   define HAVE_STRTOLL true
375 #  endif
376 #  if HAVE_STRTOLL
377 #   define strtoimax strtoll
378 #  endif
379 #  define INTMAX_MAX LLONG_MAX
380 #  define INTMAX_MIN LLONG_MIN
381 # else
382 typedef long intmax_t;
383 #  define INTMAX_MAX LONG_MAX
384 #  define INTMAX_MIN LONG_MIN
385 # endif
386 # ifndef strtoimax
387 #  define strtoimax strtol
388 # endif
389 #endif
390 
391 #ifndef PRIdMAX
392 # if INTMAX_MAX == LLONG_MAX
393 #  define PRIdMAX "lld"
394 # else
395 #  define PRIdMAX "ld"
396 # endif
397 #endif
398 
399 #ifndef PTRDIFF_MAX
400 # define PTRDIFF_MAX MAXVAL(ptrdiff_t, TYPE_BIT(ptrdiff_t))
401 #endif
402 
403 #ifndef UINT_FAST32_MAX
404 typedef unsigned long uint_fast32_t;
405 #endif
406 
407 #ifndef UINT_FAST64_MAX
408 # if 3 <= ULONG_MAX >> 31 >> 31
409 typedef unsigned long uint_fast64_t;
410 #  define UINT_FAST64_MAX ULONG_MAX
411 # else
412 /* If this fails, compile with -DHAVE_STDINT_H or with a better compiler.  */
413 typedef unsigned long long uint_fast64_t;
414 #  define UINT_FAST64_MAX ULLONG_MAX
415 # endif
416 #endif
417 
418 #ifndef UINTMAX_MAX
419 # ifdef ULLONG_MAX
420 typedef unsigned long long uintmax_t;
421 #  define UINTMAX_MAX ULLONG_MAX
422 # else
423 typedef unsigned long uintmax_t;
424 #  define UINTMAX_MAX ULONG_MAX
425 # endif
426 #endif
427 
428 #ifndef PRIuMAX
429 # ifdef ULLONG_MAX
430 #  define PRIuMAX "llu"
431 # else
432 #  define PRIuMAX "lu"
433 # endif
434 #endif
435 
436 #ifndef SIZE_MAX
437 # define SIZE_MAX ((size_t) -1)
438 #endif
439 
440 #endif /* PORT_TO_C89 */
441 
442 /* The maximum size of any created object, as a signed integer.
443    Although the C standard does not outright prohibit larger objects,
444    behavior is undefined if the result of pointer subtraction does not
445    fit into ptrdiff_t, and the code assumes in several places that
446    pointer subtraction works.  As a practical matter it's OK to not
447    support objects larger than this.  */
448 #define INDEX_MAX ((ptrdiff_t) min(PTRDIFF_MAX, SIZE_MAX))
449 
450 /* Support ckd_add, ckd_sub, ckd_mul on C23 or recent-enough GCC-like
451    hosts, unless compiled with -DHAVE_STDCKDINT_H=0 or with pre-C23 EDG.  */
452 #if !defined HAVE_STDCKDINT_H && defined __has_include
453 # if __has_include(<stdckdint.h>)
454 #  define HAVE_STDCKDINT_H true
455 # endif
456 #endif
457 #ifdef HAVE_STDCKDINT_H
458 # if HAVE_STDCKDINT_H
459 #  include <stdckdint.h>
460 # endif
461 #elif defined __EDG__
462 /* Do nothing, to work around EDG bug <https://bugs.gnu.org/53256>.  */
463 #elif defined __has_builtin
464 # if __has_builtin(__builtin_add_overflow)
465 #  define ckd_add(r, a, b) __builtin_add_overflow(a, b, r)
466 # endif
467 # if __has_builtin(__builtin_sub_overflow)
468 #  define ckd_sub(r, a, b) __builtin_sub_overflow(a, b, r)
469 # endif
470 # if __has_builtin(__builtin_mul_overflow)
471 #  define ckd_mul(r, a, b) __builtin_mul_overflow(a, b, r)
472 # endif
473 #elif 7 <= __GNUC__
474 # define ckd_add(r, a, b) __builtin_add_overflow(a, b, r)
475 # define ckd_sub(r, a, b) __builtin_sub_overflow(a, b, r)
476 # define ckd_mul(r, a, b) __builtin_mul_overflow(a, b, r)
477 #endif
478 
479 #if 3 <= __GNUC__
480 # define ATTRIBUTE_MALLOC __attribute__((__malloc__))
481 # define ATTRIBUTE_FORMAT(spec) __attribute__((__format__ spec))
482 #else
483 # define ATTRIBUTE_MALLOC /* empty */
484 # define ATTRIBUTE_FORMAT(spec) /* empty */
485 #endif
486 
487 #if (defined __has_c_attribute \
488      && (202311 <= __STDC_VERSION__ || !defined __STRICT_ANSI__))
489 # define HAVE___HAS_C_ATTRIBUTE true
490 #else
491 # define HAVE___HAS_C_ATTRIBUTE false
492 #endif
493 
494 #if HAVE___HAS_C_ATTRIBUTE
495 # if __has_c_attribute(deprecated)
496 #  define ATTRIBUTE_DEPRECATED [[deprecated]]
497 # endif
498 #endif
499 #ifndef ATTRIBUTE_DEPRECATED
500 # if 3 < __GNUC__ + (2 <= __GNUC_MINOR__)
501 #  define ATTRIBUTE_DEPRECATED __attribute__((deprecated))
502 # else
503 #  define ATTRIBUTE_DEPRECATED /* empty */
504 # endif
505 #endif
506 
507 #if HAVE___HAS_C_ATTRIBUTE
508 # if __has_c_attribute(fallthrough)
509 #  define ATTRIBUTE_FALLTHROUGH [[fallthrough]]
510 # endif
511 #endif
512 #ifndef ATTRIBUTE_FALLTHROUGH
513 # if 7 <= __GNUC__
514 #  define ATTRIBUTE_FALLTHROUGH __attribute__((fallthrough))
515 # else
516 #  define ATTRIBUTE_FALLTHROUGH ((void) 0)
517 # endif
518 #endif
519 
520 #if HAVE___HAS_C_ATTRIBUTE
521 # if __has_c_attribute(maybe_unused)
522 #  define ATTRIBUTE_MAYBE_UNUSED [[maybe_unused]]
523 # endif
524 #endif
525 #ifndef ATTRIBUTE_MAYBE_UNUSED
526 # if 2 < __GNUC__ + (7 <= __GNUC_MINOR__)
527 #  define ATTRIBUTE_MAYBE_UNUSED __attribute__((unused))
528 # else
529 #  define ATTRIBUTE_MAYBE_UNUSED /* empty */
530 # endif
531 #endif
532 
533 #if HAVE___HAS_C_ATTRIBUTE
534 # if __has_c_attribute(noreturn)
535 #  define ATTRIBUTE_NORETURN [[noreturn]]
536 # endif
537 #endif
538 #ifndef ATTRIBUTE_NORETURN
539 # if 201112 <= __STDC_VERSION__
540 #  define ATTRIBUTE_NORETURN _Noreturn
541 # elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__)
542 #  define ATTRIBUTE_NORETURN __attribute__((noreturn))
543 # else
544 #  define ATTRIBUTE_NORETURN /* empty */
545 # endif
546 #endif
547 
548 #if HAVE___HAS_C_ATTRIBUTE
549 # if __has_c_attribute(reproducible)
550 #  define ATTRIBUTE_REPRODUCIBLE [[reproducible]]
551 # endif
552 #endif
553 #ifndef ATTRIBUTE_REPRODUCIBLE
554 # if 3 <= __GNUC__
555 #  define ATTRIBUTE_REPRODUCIBLE __attribute__((pure))
556 # else
557 #  define ATTRIBUTE_REPRODUCIBLE /* empty */
558 # endif
559 #endif
560 
561 #if HAVE___HAS_C_ATTRIBUTE
562 # if __has_c_attribute(unsequenced)
563 #  define ATTRIBUTE_UNSEQUENCED [[unsequenced]]
564 # endif
565 #endif
566 #ifndef ATTRIBUTE_UNSEQUENCED
567 # if 3 <= __GNUC__
568 #  define ATTRIBUTE_UNSEQUENCED __attribute__((const))
569 # else
570 #  define ATTRIBUTE_UNSEQUENCED /* empty */
571 # endif
572 #endif
573 
574 #if (__STDC_VERSION__ < 199901 && !defined restrict \
575      && (PORT_TO_C89 || defined _MSC_VER))
576 # define restrict /* empty */
577 #endif
578 
579 /*
580 ** Workarounds for compilers/systems.
581 */
582 
583 #ifndef EPOCH_LOCAL
584 # define EPOCH_LOCAL 0
585 #endif
586 #ifndef EPOCH_OFFSET
587 # define EPOCH_OFFSET 0
588 #endif
589 #ifndef RESERVE_STD_EXT_IDS
590 # define RESERVE_STD_EXT_IDS 0
591 #endif
592 
593 /* If standard C identifiers with external linkage (e.g., localtime)
594    are reserved and are not already being renamed anyway, rename them
595    as if compiling with '-Dtime_tz=time_t'.  */
596 #if !defined time_tz && RESERVE_STD_EXT_IDS && USE_LTZ
597 # define time_tz time_t
598 #endif
599 
600 /*
601 ** Compile with -Dtime_tz=T to build the tz package with a private
602 ** time_t type equivalent to T rather than the system-supplied time_t.
603 ** This debugging feature can test unusual design decisions
604 ** (e.g., time_t wider than 'long', or unsigned time_t) even on
605 ** typical platforms.
606 */
607 #if defined time_tz || EPOCH_LOCAL || EPOCH_OFFSET != 0
608 # define TZ_TIME_T 1
609 #else
610 # define TZ_TIME_T 0
611 #endif
612 
613 #if defined LOCALTIME_IMPLEMENTATION && TZ_TIME_T
614 static time_t sys_time(time_t *x) { return time(x); }
615 #endif
616 
617 #if TZ_TIME_T
618 
619 typedef time_tz tz_time_t;
620 
621 # undef  asctime
622 # define asctime tz_asctime
623 # undef  asctime_r
624 # define asctime_r tz_asctime_r
625 # undef  ctime
626 # define ctime tz_ctime
627 # undef  ctime_r
628 # define ctime_r tz_ctime_r
629 # undef  difftime
630 # define difftime tz_difftime
631 # undef  gmtime
632 # define gmtime tz_gmtime
633 # undef  gmtime_r
634 # define gmtime_r tz_gmtime_r
635 # undef  localtime
636 # define localtime tz_localtime
637 # undef  localtime_r
638 # define localtime_r tz_localtime_r
639 # undef  localtime_rz
640 # define localtime_rz tz_localtime_rz
641 # undef  mktime
642 # define mktime tz_mktime
643 # undef  mktime_z
644 # define mktime_z tz_mktime_z
645 # undef  offtime
646 # define offtime tz_offtime
647 # undef  posix2time
648 # define posix2time tz_posix2time
649 # undef  posix2time_z
650 # define posix2time_z tz_posix2time_z
651 # undef  strftime
652 # define strftime tz_strftime
653 # undef  time
654 # define time tz_time
655 # undef  time2posix
656 # define time2posix tz_time2posix
657 # undef  time2posix_z
658 # define time2posix_z tz_time2posix_z
659 # undef  time_t
660 # define time_t tz_time_t
661 # undef  timegm
662 # define timegm tz_timegm
663 # undef  timelocal
664 # define timelocal tz_timelocal
665 # undef  timeoff
666 # define timeoff tz_timeoff
667 # undef  tzalloc
668 # define tzalloc tz_tzalloc
669 # undef  tzfree
670 # define tzfree tz_tzfree
671 # undef  tzset
672 # define tzset tz_tzset
673 # undef  tzsetwall
674 # define tzsetwall tz_tzsetwall
675 # if HAVE_STRFTIME_L
676 #  undef  strftime_l
677 #  define strftime_l tz_strftime_l
678 # endif
679 # if HAVE_TZNAME
680 #  undef  tzname
681 #  define tzname tz_tzname
682 # endif
683 # if USG_COMPAT
684 #  undef  daylight
685 #  define daylight tz_daylight
686 #  undef  timezone
687 #  define timezone tz_timezone
688 # endif
689 # if ALTZONE
690 #  undef  altzone
691 #  define altzone tz_altzone
692 # endif
693 
694 # if __STDC_VERSION__ < 202311
695 #  define DEPRECATED_IN_C23 /* empty */
696 # else
697 #  define DEPRECATED_IN_C23 ATTRIBUTE_DEPRECATED
698 # endif
699 DEPRECATED_IN_C23 char *asctime(struct tm const *);
700 char *asctime_r(struct tm const *restrict, char *restrict);
701 DEPRECATED_IN_C23 char *ctime(time_t const *);
702 char *ctime_r(time_t const *, char *);
703 ATTRIBUTE_UNSEQUENCED double difftime(time_t, time_t);
704 size_t strftime(char *restrict, size_t, char const *restrict,
705 		struct tm const *restrict);
706 # if HAVE_STRFTIME_L
707 size_t strftime_l(char *restrict, size_t, char const *restrict,
708 		  struct tm const *restrict, locale_t);
709 # endif
710 struct tm *gmtime(time_t const *);
711 struct tm *gmtime_r(time_t const *restrict, struct tm *restrict);
712 struct tm *localtime(time_t const *);
713 struct tm *localtime_r(time_t const *restrict, struct tm *restrict);
714 time_t mktime(struct tm *);
715 time_t time(time_t *);
716 time_t timegm(struct tm *);
717 void tzset(void);
718 #endif
719 
720 #ifndef HAVE_DECL_TIMEGM
721 # if (202311 <= __STDC_VERSION__ \
722       || defined __GLIBC__ || defined __tm_zone /* musl */ \
723       || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ \
724       || (defined __APPLE__ && defined __MACH__))
725 #  define HAVE_DECL_TIMEGM true
726 # else
727 #  define HAVE_DECL_TIMEGM false
728 # endif
729 #endif
730 #if !HAVE_DECL_TIMEGM && !defined timegm
731 time_t timegm(struct tm *);
732 #endif
733 
734 #if !HAVE_DECL_ASCTIME_R && !defined asctime_r
735 extern char *asctime_r(struct tm const *restrict, char *restrict);
736 #endif
737 
738 #ifndef HAVE_DECL_ENVIRON
739 # if defined environ || defined __USE_GNU
740 #  define HAVE_DECL_ENVIRON 1
741 # else
742 #  define HAVE_DECL_ENVIRON 0
743 # endif
744 #endif
745 
746 #if !HAVE_DECL_ENVIRON
747 extern char **environ;
748 #endif
749 
750 #if 2 <= HAVE_TZNAME + (TZ_TIME_T || !HAVE_POSIX_DECLS)
751 extern char *tzname[];
752 #endif
753 #if 2 <= USG_COMPAT + (TZ_TIME_T || !HAVE_POSIX_DECLS)
754 extern long timezone;
755 extern int daylight;
756 #endif
757 #if 2 <= ALTZONE + (TZ_TIME_T || !HAVE_POSIX_DECLS)
758 extern long altzone;
759 #endif
760 
761 /*
762 ** The STD_INSPIRED functions are similar, but most also need
763 ** declarations if time_tz is defined.
764 */
765 
766 #ifndef STD_INSPIRED
767 # define STD_INSPIRED 0
768 #endif
769 #if STD_INSPIRED
770 # if TZ_TIME_T || !defined tzsetwall
771 void tzsetwall(void);
772 # endif
773 # if TZ_TIME_T || !defined offtime
774 struct tm *offtime(time_t const *, long);
775 # endif
776 # if TZ_TIME_T || !defined timelocal
777 time_t timelocal(struct tm *);
778 # endif
779 # if TZ_TIME_T || !defined timeoff
780 time_t timeoff(struct tm *, long);
781 # endif
782 # if TZ_TIME_T || !defined time2posix
783 time_t time2posix(time_t);
784 # endif
785 # if TZ_TIME_T || !defined posix2time
786 time_t posix2time(time_t);
787 # endif
788 #endif
789 
790 /* Infer TM_ZONE on systems where this information is known, but suppress
791    guessing if NO_TM_ZONE is defined.  Similarly for TM_GMTOFF.  */
792 #if (defined __GLIBC__ \
793      || defined __tm_zone /* musl */ \
794      || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ \
795      || (defined __APPLE__ && defined __MACH__))
796 # if !defined TM_GMTOFF && !defined NO_TM_GMTOFF
797 #  define TM_GMTOFF tm_gmtoff
798 # endif
799 # if !defined TM_ZONE && !defined NO_TM_ZONE
800 #  define TM_ZONE tm_zone
801 # endif
802 #endif
803 
804 /*
805 ** Define functions that are ABI compatible with NetBSD but have
806 ** better prototypes.  NetBSD 6.1.4 defines a pointer type timezone_t
807 ** and labors under the misconception that 'const timezone_t' is a
808 ** pointer to a constant.  This use of 'const' is ineffective, so it
809 ** is not done here.  What we call 'struct state' NetBSD calls
810 ** 'struct __state', but this is a private name so it doesn't matter.
811 */
812 #ifndef __NetBSD__
813 #if NETBSD_INSPIRED
814 typedef struct state *timezone_t;
815 struct tm *localtime_rz(timezone_t restrict, time_t const *restrict,
816 			struct tm *restrict);
817 time_t mktime_z(timezone_t restrict, struct tm *restrict);
818 timezone_t tzalloc(char const *);
819 void tzfree(timezone_t);
820 # if STD_INSPIRED
821 #  if TZ_TIME_T || !defined posix2time_z
822 ATTRIBUTE_REPRODUCIBLE time_t posix2time_z(timezone_t __restrict, time_t);
823 #  endif
824 #  if TZ_TIME_T || !defined time2posix_z
825 ATTRIBUTE_REPRODUCIBLE time_t time2posix_z(timezone_t __restrict, time_t);
826 #  endif
827 # endif
828 #endif
829 #endif
830 
831 /*
832 ** Finally, some convenience items.
833 */
834 
835 #define TYPE_BIT(type) (CHAR_BIT * (ptrdiff_t) sizeof(type))
836 #define TYPE_SIGNED(type) (/*CONSTCOND*/((type) -1) < 0)
837 #define TWOS_COMPLEMENT(t) (/*CONSTCOND*/(t) ~ (t) 0 < 0)
838 
839 /* Minimum and maximum of two values.  Use lower case to avoid
840    naming clashes with standard include files.  */
841 #define max(a, b) ((a) > (b) ? (a) : (b))
842 #define min(a, b) ((a) < (b) ? (a) : (b))
843 
844 /* Max and min values of the integer type T, of which only the bottom
845    B bits are used, and where the highest-order used bit is considered
846    to be a sign bit if T is signed.  */
847 #define MAXVAL(t, b) /*LINTED*/					\
848   ((t) (((t) 1 << ((b) - 1 - TYPE_SIGNED(t)))			\
849 	- 1 + ((t) 1 << ((b) - 1 - TYPE_SIGNED(t)))))
850 #define MINVAL(t, b)						\
851   ((t) (TYPE_SIGNED(t) ? - TWOS_COMPLEMENT(t) - MAXVAL(t, b) : 0))
852 
853 /* The extreme time values, assuming no padding.  */
854 #define TIME_T_MIN_NO_PADDING MINVAL(time_t, TYPE_BIT(time_t))
855 #define TIME_T_MAX_NO_PADDING MAXVAL(time_t, TYPE_BIT(time_t))
856 
857 /* The extreme time values.  These are macros, not constants, so that
858    any portability problems occur only when compiling .c files that use
859    the macros, which is safer for applications that need only zdump and zic.
860    This implementation assumes no padding if time_t is signed and
861    either the compiler lacks support for _Generic or time_t is not one
862    of the standard signed integer types.  */
863 #if HAVE__GENERIC
864 # define TIME_T_MIN \
865     _Generic((time_t) 0, \
866 	     signed char: SCHAR_MIN, short: SHRT_MIN, \
867 	     int: INT_MIN, long: LONG_MIN, long long: LLONG_MIN, \
868 	     default: TIME_T_MIN_NO_PADDING)
869 # define TIME_T_MAX \
870     (TYPE_SIGNED(time_t) \
871      ? _Generic((time_t) 0, \
872 		signed char: SCHAR_MAX, short: SHRT_MAX, \
873 		int: INT_MAX, long: LONG_MAX, long long: LLONG_MAX, \
874 		default: TIME_T_MAX_NO_PADDING)			    \
875      : (time_t) -1)
876 enum { SIGNED_PADDING_CHECK_NEEDED
877          = _Generic((time_t) 0,
878 		    signed char: false, short: false,
879 		    int: false, long: false, long long: false,
880 		    default: true) };
881 #else
882 # define TIME_T_MIN TIME_T_MIN_NO_PADDING
883 # define TIME_T_MAX TIME_T_MAX_NO_PADDING
884 enum { SIGNED_PADDING_CHECK_NEEDED = true };
885 #endif
886 /* Try to check the padding assumptions.  Although TIME_T_MAX and the
887    following check can both have undefined behavior on oddball
888    platforms due to shifts exceeding widths of signed integers, these
889    platforms' compilers are likely to diagnose these issues in integer
890    constant expressions, so it shouldn't hurt to check statically.  */
891 static_assert(! TYPE_SIGNED(time_t) || ! SIGNED_PADDING_CHECK_NEEDED
892 	      || TIME_T_MAX >> (TYPE_BIT(time_t) - 2) == 1);
893 
894 /*
895 ** 302 / 1000 is log10(2.0) rounded up.
896 ** Subtract one for the sign bit if the type is signed;
897 ** add one for integer division truncation;
898 ** add one more for a minus sign if the type is signed.
899 */
900 #define INT_STRLEN_MAXIMUM(type) \
901 	((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + \
902 	1 + TYPE_SIGNED(type))
903 
904 /*
905 ** INITIALIZE(x)
906 */
907 
908 #if defined(__GNUC__) || defined(__lint__)
909 # define INITIALIZE(x)	((x) = 0)
910 #else
911 # define INITIALIZE(x)
912 #endif
913 
914 /* Whether memory access must strictly follow the C standard.
915    If 0, it's OK to read uninitialized storage so long as the value is
916    not relied upon.  Defining it to 0 lets mktime access parts of
917    struct tm that might be uninitialized, as a heuristic when the
918    standard doesn't say what to return and when tm_gmtoff can help
919    mktime likely infer a better value.  */
920 #ifndef UNINIT_TRAP
921 # define UNINIT_TRAP 0
922 #endif
923 
924 #ifdef DEBUG
925 # undef unreachable
926 # define unreachable() abort()
927 #elif !defined unreachable
928 # ifdef __has_builtin
929 #  if __has_builtin(__builtin_unreachable)
930 #   define unreachable() __builtin_unreachable()
931 #  endif
932 # elif 4 < __GNUC__ + (5 <= __GNUC_MINOR__)
933 #  define unreachable() __builtin_unreachable()
934 # endif
935 # ifndef unreachable
936 #  define unreachable() ((void) 0)
937 # endif
938 #endif
939 
940 /*
941 ** For the benefit of GNU folk...
942 ** '_(MSGID)' uses the current locale's message library string for MSGID.
943 ** The default is to use gettext if available, and use MSGID otherwise.
944 */
945 
946 #if HAVE_GETTEXT
947 #define _(msgid) gettext(msgid)
948 #else /* !HAVE_GETTEXT */
949 #define _(msgid) msgid
950 #endif /* !HAVE_GETTEXT */
951 
952 #if !defined TZ_DOMAIN && defined HAVE_GETTEXT
953 # define TZ_DOMAIN "tz"
954 #endif
955 
956 #if HAVE_INCOMPATIBLE_CTIME_R
957 #undef asctime_r
958 #undef ctime_r
959 char *asctime_r(struct tm const *restrict, char *restrict);
960 char *ctime_r(time_t const *, char *);
961 #endif /* HAVE_INCOMPATIBLE_CTIME_R */
962 
963 /* Handy macros that are independent of tzfile implementation.  */
964 
965 #ifndef SECSPERMIN
966 enum {
967   SECSPERMIN = 60,
968   MINSPERHOUR = 60,
969   SECSPERHOUR = SECSPERMIN * MINSPERHOUR,
970   HOURSPERDAY = 24,
971   DAYSPERWEEK = 7,
972   DAYSPERNYEAR = 365,
973   DAYSPERLYEAR = DAYSPERNYEAR + 1,
974   MONSPERYEAR = 12,
975   YEARSPERREPEAT = 400	/* years before a Gregorian repeat */
976 };
977 #endif
978 
979 #define SECSPERDAY	((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
980 
981 #define DAYSPERREPEAT		((int_fast32_t) 400 * 365 + 100 - 4 + 1)
982 #define SECSPERREPEAT		((int_fast64_t) DAYSPERREPEAT * SECSPERDAY)
983 #define AVGSECSPERYEAR		(SECSPERREPEAT / YEARSPERREPEAT)
984 
985 #ifndef TM_SUNDAY
986 enum {
987   TM_SUNDAY,
988   TM_MONDAY,
989   TM_TUESDAY,
990   TM_WEDNESDAY,
991   TM_THURSDAY,
992   TM_FRIDAY,
993   TM_SATURDAY
994 };
995 #endif
996 
997 #ifndef TM_JANUARY
998 enum {
999   TM_JANUARY,
1000   TM_FEBRUARY,
1001   TM_MARCH,
1002   TM_APRIL,
1003   TM_MAY,
1004   TM_JUNE,
1005   TM_JULY,
1006   TM_AUGUST,
1007   TM_SEPTEMBER,
1008   TM_OCTOBER,
1009   TM_NOVEMBER,
1010   TM_DECEMBER
1011 };
1012 #endif
1013 
1014 #ifndef TM_YEAR_BASE
1015 enum {
1016   TM_YEAR_BASE = 1900,
1017   TM_WDAY_BASE = TM_MONDAY,
1018   EPOCH_YEAR = 1970,
1019   EPOCH_WDAY = TM_THURSDAY
1020 };
1021 #endif
1022 
1023 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
1024 
1025 /*
1026 ** Since everything in isleap is modulo 400 (or a factor of 400), we know that
1027 **	isleap(y) == isleap(y % 400)
1028 ** and so
1029 **	isleap(a + b) == isleap((a + b) % 400)
1030 ** or
1031 **	isleap(a + b) == isleap(a % 400 + b % 400)
1032 ** This is true even if % means modulo rather than Fortran remainder
1033 ** (which is allowed by C89 but not by C99 or later).
1034 ** We use this to avoid addition overflow problems.
1035 */
1036 
1037 #define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
1038 
1039 #ifdef _LIBC
1040 #include "reentrant.h"
1041 extern struct __state *__lclptr;
1042 #if defined(__LIBC12_SOURCE__)
1043 #define tzset_unlocked __tzset_unlocked
1044 #else
1045 #define tzset_unlocked __tzset_unlocked50
1046 #endif
1047 
1048 void tzset_unlocked(void);
1049 #ifdef _REENTRANT
1050 extern rwlock_t __lcl_lock;
1051 #endif
1052 #endif
1053 
1054 #endif /* !defined PRIVATE_H */
1055