1/* Private header for tzdb code. */
2
3#ifndef PRIVATE_H
4
5#define PRIVATE_H
6
7/*
8** This file is in the public domain, so clarified as of
9** 1996-06-05 by Arthur David Olson.
10*/
11
12/*
13** This header is for use ONLY with the time conversion code.
14** There is no guarantee that it will remain unchanged,
15** or that it will remain at all.
16** Do NOT copy it to any system include directory.
17** Thank you!
18*/
19
20/*
21** zdump has been made independent of the rest of the time
22** conversion package to increase confidence in the verification it provides.
23** You can use zdump to help in verifying other implementations.
24** To do this, compile with -DUSE_LTZ=0 and link without the tz library.
25*/
26#ifndef USE_LTZ
27# define USE_LTZ 1
28#endif
29
30/* This string was in the Factory zone through version 2016f. */
31#define GRANDPARENTED "Local time zone must be set--see zic manual page"
32
33/*
34** Defaults for preprocessor symbols.
35** You can override these in your C compiler options, e.g. '-DHAVE_GETTEXT=1'.
36*/
37
38#ifndef HAVE_DECL_ASCTIME_R
39#define HAVE_DECL_ASCTIME_R 1
40#endif
41
42#if !defined HAVE_GENERIC && defined __has_extension
43# if __has_extension(c_generic_selections)
44# define HAVE_GENERIC 1
45# else
46# define HAVE_GENERIC 0
47# endif
48#endif
49/* _Generic is buggy in pre-4.9 GCC. */
50#if !defined HAVE_GENERIC && defined __GNUC__
51# define HAVE_GENERIC (4 < __GNUC__ + (9 <= __GNUC_MINOR__))
52#endif
53#ifndef HAVE_GENERIC
54# define HAVE_GENERIC (201112 <= __STDC_VERSION__)
55#endif
56
57#ifndef HAVE_GETTEXT
58#define HAVE_GETTEXT 0
59#endif /* !defined HAVE_GETTEXT */
60
61#ifndef HAVE_INCOMPATIBLE_CTIME_R
62#define HAVE_INCOMPATIBLE_CTIME_R 0
63#endif
64
65#ifndef HAVE_LINK
66#define HAVE_LINK 1
67#endif /* !defined HAVE_LINK */
68
69#ifndef HAVE_POSIX_DECLS
70#define HAVE_POSIX_DECLS 1
71#endif
72
73#ifndef HAVE_STDBOOL_H
74#define HAVE_STDBOOL_H (199901 <= __STDC_VERSION__)
75#endif
76
77#ifndef HAVE_STRDUP
78#define HAVE_STRDUP 1
79#endif
80
81#ifndef HAVE_STRTOLL
82#define HAVE_STRTOLL 1
83#endif
84
85#ifndef HAVE_SYMLINK
86#define HAVE_SYMLINK 1
87#endif /* !defined HAVE_SYMLINK */
88
89#ifndef HAVE_SYS_STAT_H
90#define HAVE_SYS_STAT_H 1
91#endif /* !defined HAVE_SYS_STAT_H */
92
93#ifndef HAVE_SYS_WAIT_H
94#define HAVE_SYS_WAIT_H 1
95#endif /* !defined HAVE_SYS_WAIT_H */
96
97#ifndef HAVE_UNISTD_H
98#define HAVE_UNISTD_H 1
99#endif /* !defined HAVE_UNISTD_H */
100
101#ifndef HAVE_UTMPX_H
102#define HAVE_UTMPX_H 1
103#endif /* !defined HAVE_UTMPX_H */
104
105#ifndef NETBSD_INSPIRED
106# define NETBSD_INSPIRED 1
107#endif
108
109#if HAVE_INCOMPATIBLE_CTIME_R
110#define asctime_r _incompatible_asctime_r
111#define ctime_r _incompatible_ctime_r
112#endif /* HAVE_INCOMPATIBLE_CTIME_R */
113
114/* Enable tm_gmtoff, tm_zone, and environ on GNUish systems. */
115#define _GNU_SOURCE 1
116/* Fix asctime_r on Solaris 11. */
117#define _POSIX_PTHREAD_SEMANTICS 1
118/* Enable strtoimax on pre-C99 Solaris 11. */
119#define __EXTENSIONS__ 1
120
121/* To avoid having 'stat' fail unnecessarily with errno == EOVERFLOW,
122 enable large files on GNUish systems ... */
123#ifndef _FILE_OFFSET_BITS
124# define _FILE_OFFSET_BITS 64
125#endif
126/* ... and on AIX ... */
127#define _LARGE_FILES 1
128/* ... and enable large inode numbers on Mac OS X 10.5 and later. */
129#define _DARWIN_USE_64_BIT_INODE 1
130
131/*
132** Nested includes
133*/
134
135/* Avoid clashes with NetBSD by renaming NetBSD's declarations.
136 If defining the 'timezone' variable, avoid a clash with FreeBSD's
137 'timezone' function by renaming its declaration. */
138#define localtime_rz sys_localtime_rz
139#define mktime_z sys_mktime_z
140#define posix2time_z sys_posix2time_z
141#define time2posix_z sys_time2posix_z
142#if defined USG_COMPAT && USG_COMPAT == 2
143# define timezone sys_timezone
144#endif
145#define timezone_t sys_timezone_t
146#define tzalloc sys_tzalloc
147#define tzfree sys_tzfree
148#include <time.h>
149#undef localtime_rz
150#undef mktime_z
151#undef posix2time_z
152#undef time2posix_z
153#if defined USG_COMPAT && USG_COMPAT == 2
154# undef timezone
155#endif
156#undef timezone_t
157#undef tzalloc
158#undef tzfree
159
160#include <sys/types.h> /* for time_t */
161#include <string.h>
162#include <limits.h> /* for CHAR_BIT et al. */
163#include <stdlib.h>
164
165#include <errno.h>
166
167#ifndef ENAMETOOLONG
168# define ENAMETOOLONG EINVAL
169#endif
170#ifndef ENOTSUP
171# define ENOTSUP EINVAL
172#endif
173#ifndef EOVERFLOW
174# define EOVERFLOW EINVAL
175#endif
176
177#if HAVE_GETTEXT
178#include <libintl.h>
179#endif /* HAVE_GETTEXT */
180
181#if HAVE_UNISTD_H
182#include <unistd.h> /* for R_OK, and other POSIX goodness */
183#endif /* HAVE_UNISTD_H */
184
185#ifndef HAVE_STRFTIME_L
186# if _POSIX_VERSION < 200809
187# define HAVE_STRFTIME_L 0
188# else
189# define HAVE_STRFTIME_L 1
190# endif
191#endif
192
193#ifndef USG_COMPAT
194# ifndef _XOPEN_VERSION
195# define USG_COMPAT 0
196# else
197# define USG_COMPAT 1
198# endif
199#endif
200
201#ifndef HAVE_TZNAME
202# if _POSIX_VERSION < 198808 && !USG_COMPAT
203# define HAVE_TZNAME 0
204# else
205# define HAVE_TZNAME 1
206# endif
207#endif
208
209#ifndef ALTZONE
210# if defined __sun || defined _M_XENIX
211# define ALTZONE 1
212# else
213# define ALTZONE 0
214# endif
215#endif
216
217#ifndef R_OK
218#define R_OK 4
219#endif /* !defined R_OK */
220
221/* Unlike <ctype.h>'s isdigit, this also works if c < 0 | c > UCHAR_MAX. */
222#define is_digit(c) ((unsigned)(c) - '0' <= 9)
223
224/*
225** Define HAVE_STDINT_H's default value here, rather than at the
226** start, since __GLIBC__ and INTMAX_MAX's values depend on
227** previously-included files. glibc 2.1 and Solaris 10 and later have
228** stdint.h, even with pre-C99 compilers.
229*/
230#ifndef HAVE_STDINT_H
231#define HAVE_STDINT_H \
232 (199901 <= __STDC_VERSION__ \
233 || 2 < __GLIBC__ + (1 <= __GLIBC_MINOR__) \
234 || __CYGWIN__ || INTMAX_MAX)
235#endif /* !defined HAVE_STDINT_H */
236
237#if HAVE_STDINT_H
238#include <stdint.h>
239#endif /* !HAVE_STDINT_H */
240
241#ifndef HAVE_INTTYPES_H
242# define HAVE_INTTYPES_H HAVE_STDINT_H
243#endif
244#if HAVE_INTTYPES_H
245# include <inttypes.h>
246#endif
247
248/* Pre-C99 GCC compilers define __LONG_LONG_MAX__ instead of LLONG_MAX. */
249#ifdef __LONG_LONG_MAX__
250# ifndef LLONG_MAX
251# define LLONG_MAX __LONG_LONG_MAX__
252# endif
253# ifndef LLONG_MIN
254# define LLONG_MIN (-1 - LLONG_MAX)
255# endif
256#endif
257
258#ifndef INT_FAST64_MAX
259# ifdef LLONG_MAX
260typedef long long int_fast64_t;
261# define INT_FAST64_MIN LLONG_MIN
262# define INT_FAST64_MAX LLONG_MAX
263# else
264# if LONG_MAX >> 31 < 0xffffffff
265Please use a compiler that supports a 64-bit integer type (or wider);
266you may need to compile with "-DHAVE_STDINT_H".
267# endif
268typedef long int_fast64_t;
269# define INT_FAST64_MIN LONG_MIN
270# define INT_FAST64_MAX LONG_MAX
271# endif
272#endif
273
274#ifndef PRIdFAST64
275# if INT_FAST64_MAX == LLONG_MAX
276# define PRIdFAST64 "lld"
277# else
278# define PRIdFAST64 "ld"
279# endif
280#endif
281
282#ifndef SCNdFAST64
283# define SCNdFAST64 PRIdFAST64
284#endif
285
286#ifndef INT_FAST32_MAX
287# if INT_MAX >> 31 == 0
288typedef long int_fast32_t;
289# define INT_FAST32_MAX LONG_MAX
290# define INT_FAST32_MIN LONG_MIN
291# else
292typedef int int_fast32_t;
293# define INT_FAST32_MAX INT_MAX
294# define INT_FAST32_MIN INT_MIN
295# endif
296#endif
297
298#ifndef INTMAX_MAX
299# ifdef LLONG_MAX
300typedef long long intmax_t;
301# if HAVE_STRTOLL
302# define strtoimax strtoll
303# endif
304# define INTMAX_MAX LLONG_MAX
305# define INTMAX_MIN LLONG_MIN
306# else
307typedef long intmax_t;
308# define INTMAX_MAX LONG_MAX
309# define INTMAX_MIN LONG_MIN
310# endif
311# ifndef strtoimax
312# define strtoimax strtol
313# endif
314#endif
315
316#ifndef PRIdMAX
317# if INTMAX_MAX == LLONG_MAX
318# define PRIdMAX "lld"
319# else
320# define PRIdMAX "ld"
321# endif
322#endif
323
324#ifndef UINT_FAST64_MAX
325# if defined ULLONG_MAX || defined __LONG_LONG_MAX__
326typedef unsigned long long uint_fast64_t;
327# else
328# if ULONG_MAX >> 31 >> 1 < 0xffffffff
329Please use a compiler that supports a 64-bit integer type (or wider);
330you may need to compile with "-DHAVE_STDINT_H".
331# endif
332typedef unsigned long uint_fast64_t;
333# endif
334#endif
335
336#ifndef UINTMAX_MAX
337# if defined ULLONG_MAX || defined __LONG_LONG_MAX__
338typedef unsigned long long uintmax_t;
339# else
340typedef unsigned long uintmax_t;
341# endif
342#endif
343
344#ifndef PRIuMAX
345# if defined ULLONG_MAX || defined __LONG_LONG_MAX__
346# define PRIuMAX "llu"
347# else
348# define PRIuMAX "lu"
349# endif
350#endif
351
352#ifndef INT32_MAX
353#define INT32_MAX 0x7fffffff
354#endif /* !defined INT32_MAX */
355#ifndef INT32_MIN
356#define INT32_MIN (-1 - INT32_MAX)
357#endif /* !defined INT32_MIN */
358
359#ifndef SIZE_MAX
360#define SIZE_MAX ((size_t) -1)
361#endif
362
363#if 3 <= __GNUC__
364# define ATTRIBUTE_CONST __attribute__ ((const))
365# define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
366# define ATTRIBUTE_PURE __attribute__ ((__pure__))
367# define ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
368#else
369# define ATTRIBUTE_CONST /* empty */
370# define ATTRIBUTE_MALLOC /* empty */
371# define ATTRIBUTE_PURE /* empty */
372# define ATTRIBUTE_FORMAT(spec) /* empty */
373#endif
374
375#if !defined _Noreturn && __STDC_VERSION__ < 201112
376# if 2 < __GNUC__ + (8 <= __GNUC_MINOR__)
377# define _Noreturn __attribute__ ((__noreturn__))
378# else
379# define _Noreturn
380# endif
381#endif
382
383#if __STDC_VERSION__ < 199901 && !defined restrict
384# define restrict /* empty */
385#endif
386
387/*
388** Workarounds for compilers/systems.
389*/
390
391#ifndef EPOCH_LOCAL
392# define EPOCH_LOCAL 0
393#endif
394#ifndef EPOCH_OFFSET
395# define EPOCH_OFFSET 0
396#endif
397#ifndef RESERVE_STD_EXT_IDS
398# define RESERVE_STD_EXT_IDS 0
399#endif
400
401/* If standard C identifiers with external linkage (e.g., localtime)
402 are reserved and are not already being renamed anyway, rename them
403 as if compiling with '-Dtime_tz=time_t'. */
404#if !defined time_tz && RESERVE_STD_EXT_IDS && USE_LTZ
405# define time_tz time_t
406#endif
407
408/*
409** Compile with -Dtime_tz=T to build the tz package with a private
410** time_t type equivalent to T rather than the system-supplied time_t.
411** This debugging feature can test unusual design decisions
412** (e.g., time_t wider than 'long', or unsigned time_t) even on
413** typical platforms.
414*/
415#if defined time_tz || EPOCH_LOCAL || EPOCH_OFFSET != 0
416# define TZ_TIME_T 1
417#else
418# define TZ_TIME_T 0
419#endif
420
421#if TZ_TIME_T
422# ifdef LOCALTIME_IMPLEMENTATION
423static time_t sys_time(time_t *x) { return time(x); }
424# endif
425
426typedef time_tz tz_time_t;
427
428# undef asctime
429# define asctime tz_asctime
430# undef asctime_r
431# define asctime_r tz_asctime_r
432# undef ctime
433# define ctime tz_ctime
434# undef ctime_r
435# define ctime_r tz_ctime_r
436# undef difftime
437# define difftime tz_difftime
438# undef gmtime
439# define gmtime tz_gmtime
440# undef gmtime_r
441# define gmtime_r tz_gmtime_r
442# undef localtime
443# define localtime tz_localtime
444# undef localtime_r
445# define localtime_r tz_localtime_r
446# undef localtime_rz
447# define localtime_rz tz_localtime_rz
448# undef mktime
449# define mktime tz_mktime
450# undef mktime_z
451# define mktime_z tz_mktime_z
452# undef offtime
453# define offtime tz_offtime
454# undef posix2time
455# define posix2time tz_posix2time
456# undef posix2time_z
457# define posix2time_z tz_posix2time_z
458# undef strftime
459# define strftime tz_strftime
460# undef time
461# define time tz_time
462# undef time2posix
463# define time2posix tz_time2posix
464# undef time2posix_z
465# define time2posix_z tz_time2posix_z
466# undef time_t
467# define time_t tz_time_t
468# undef timegm
469# define timegm tz_timegm
470# undef timelocal
471# define timelocal tz_timelocal
472# undef timeoff
473# define timeoff tz_timeoff
474# undef tzalloc
475# define tzalloc tz_tzalloc
476# undef tzfree
477# define tzfree tz_tzfree
478# undef tzset
479# define tzset tz_tzset
480# undef tzsetwall
481# define tzsetwall tz_tzsetwall
482# if HAVE_STRFTIME_L
483# undef strftime_l
484# define strftime_l tz_strftime_l
485# endif
486# if HAVE_TZNAME
487# undef tzname
488# define tzname tz_tzname
489# endif
490# if USG_COMPAT
491# undef daylight
492# define daylight tz_daylight
493# undef timezone
494# define timezone tz_timezone
495# endif
496# if ALTZONE
497# undef altzone
498# define altzone tz_altzone
499# endif
500
501char *asctime(struct tm const *);
502char *asctime_r(struct tm const *restrict, char *restrict);
503char *ctime(time_t const *);
504char *ctime_r(time_t const *, char *);
505double difftime(time_t, time_t) ATTRIBUTE_CONST;
506size_t strftime(char *restrict, size_t, char const *restrict,
507 struct tm const *restrict);
508# if HAVE_STRFTIME_L
509size_t strftime_l(char *restrict, size_t, char const *restrict,
510 struct tm const *restrict, locale_t);
511# endif
512struct tm *gmtime(time_t const *);
513struct tm *gmtime_r(time_t const *restrict, struct tm *restrict);
514struct tm *localtime(time_t const *);
515struct tm *localtime_r(time_t const *restrict, struct tm *restrict);
516time_t mktime(struct tm *);
517time_t time(time_t *);
518void tzset(void);
519#endif
520
521#if !HAVE_DECL_ASCTIME_R && !defined asctime_r
522extern char *asctime_r(struct tm const *restrict, char *restrict);
523#endif
524
525#ifndef HAVE_DECL_ENVIRON
526# if defined environ || defined __USE_GNU
527# define HAVE_DECL_ENVIRON 1
528# else
529# define HAVE_DECL_ENVIRON 0
530# endif
531#endif
532
533#if !HAVE_DECL_ENVIRON
534extern char **environ;
535#endif
536
537#if 2 <= HAVE_TZNAME + (TZ_TIME_T || !HAVE_POSIX_DECLS)
538extern char *tzname[];
539#endif
540#if 2 <= USG_COMPAT + (TZ_TIME_T || !HAVE_POSIX_DECLS)
541extern long timezone;
542extern int daylight;
543#endif
544#if 2 <= ALTZONE + (TZ_TIME_T || !HAVE_POSIX_DECLS)
545extern long altzone;
546#endif
547
548/*
549** The STD_INSPIRED functions are similar, but most also need
550** declarations if time_tz is defined.
551*/
552
553#ifdef STD_INSPIRED
554# if TZ_TIME_T || !defined tzsetwall
555void tzsetwall(void);
556# endif
557# if TZ_TIME_T || !defined offtime
558struct tm *offtime(time_t const *, long);
559# endif
560# if TZ_TIME_T || !defined timegm
561time_t timegm(struct tm *);
562# endif
563# if TZ_TIME_T || !defined timelocal
564time_t timelocal(struct tm *);
565# endif
566# if TZ_TIME_T || !defined timeoff
567time_t timeoff(struct tm *, long);
568# endif
569# if TZ_TIME_T || !defined time2posix
570time_t time2posix(time_t);
571# endif
572# if TZ_TIME_T || !defined posix2time
573time_t posix2time(time_t);
574# endif
575#endif
576
577/* Infer TM_ZONE on systems where this information is known, but suppress
578 guessing if NO_TM_ZONE is defined. Similarly for TM_GMTOFF. */
579#if (defined __GLIBC__ \
580 || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ \
581 || (defined __APPLE__ && defined __MACH__))
582# if !defined TM_GMTOFF && !defined NO_TM_GMTOFF
583# define TM_GMTOFF tm_gmtoff
584# endif
585# if !defined TM_ZONE && !defined NO_TM_ZONE
586# define TM_ZONE tm_zone
587# endif
588#endif
589
590/*
591** Define functions that are ABI compatible with NetBSD but have
592** better prototypes. NetBSD 6.1.4 defines a pointer type timezone_t
593** and labors under the misconception that 'const timezone_t' is a
594** pointer to a constant. This use of 'const' is ineffective, so it
595** is not done here. What we call 'struct state' NetBSD calls
596** 'struct __state', but this is a private name so it doesn't matter.
597*/
598#if NETBSD_INSPIRED
599typedef struct state *timezone_t;
600struct tm *localtime_rz(timezone_t restrict, time_t const *restrict,
601 struct tm *restrict);
602time_t mktime_z(timezone_t restrict, struct tm *restrict);
603timezone_t tzalloc(char const *);
604void tzfree(timezone_t);
605# ifdef STD_INSPIRED
606# if TZ_TIME_T || !defined posix2time_z
607time_t posix2time_z(timezone_t, time_t) ATTRIBUTE_PURE;
608# endif
609# if TZ_TIME_T || !defined time2posix_z
610time_t time2posix_z(timezone_t, time_t) ATTRIBUTE_PURE;
611# endif
612# endif
613#endif
614
615/*
616** Finally, some convenience items.
617*/
618
619#if HAVE_STDBOOL_H
620# include <stdbool.h>
621#else
622# define true 1
623# define false 0
624# define bool int
625#endif
626
627#define TYPE_BIT(type) (sizeof (type) * CHAR_BIT)
628#define TYPE_SIGNED(type) (((type) -1) < 0)
629#define TWOS_COMPLEMENT(t) ((t) ~ (t) 0 < 0)
630
631/* Max and min values of the integer type T, of which only the bottom
632 B bits are used, and where the highest-order used bit is considered
633 to be a sign bit if T is signed. */
634#define MAXVAL(t, b) \
635 ((t) (((t) 1 << ((b) - 1 - TYPE_SIGNED(t))) \
636 - 1 + ((t) 1 << ((b) - 1 - TYPE_SIGNED(t)))))
637#define MINVAL(t, b) \
638 ((t) (TYPE_SIGNED(t) ? - TWOS_COMPLEMENT(t) - MAXVAL(t, b) : 0))
639
640/* The extreme time values, assuming no padding. */
641#define TIME_T_MIN_NO_PADDING MINVAL(time_t, TYPE_BIT(time_t))
642#define TIME_T_MAX_NO_PADDING MAXVAL(time_t, TYPE_BIT(time_t))
643
644/* The extreme time values. These are macros, not constants, so that
645 any portability problem occur only when compiling .c files that use
646 the macros, which is safer for applications that need only zdump and zic.
647 This implementation assumes no padding if time_t is signed and
648 either the compiler lacks support for _Generic or time_t is not one
649 of the standard signed integer types. */
650#if HAVE_GENERIC
651# define TIME_T_MIN \
652 _Generic((time_t) 0, \
653 signed char: SCHAR_MIN, short: SHRT_MIN, \
654 int: INT_MIN, long: LONG_MIN, long long: LLONG_MIN, \
655 default: TIME_T_MIN_NO_PADDING)
656# define TIME_T_MAX \
657 (TYPE_SIGNED(time_t) \
658 ? _Generic((time_t) 0, \
659 signed char: SCHAR_MAX, short: SHRT_MAX, \
660 int: INT_MAX, long: LONG_MAX, long long: LLONG_MAX, \
661 default: TIME_T_MAX_NO_PADDING) \
662 : (time_t) -1)
663#else
664# define TIME_T_MIN TIME_T_MIN_NO_PADDING
665# define TIME_T_MAX TIME_T_MAX_NO_PADDING
666#endif
667
668/*
669** 302 / 1000 is log10(2.0) rounded up.
670** Subtract one for the sign bit if the type is signed;
671** add one for integer division truncation;
672** add one more for a minus sign if the type is signed.
673*/
674#define INT_STRLEN_MAXIMUM(type) \
675 ((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + \
676 1 + TYPE_SIGNED(type))
677
678/*
679** INITIALIZE(x)
680*/
681
682#ifdef GCC_LINT
683# define INITIALIZE(x) ((x) = 0)
684#else
685# define INITIALIZE(x)
686#endif
687
688#ifndef UNINIT_TRAP
689# define UNINIT_TRAP 0
690#endif
691
692/*
693** For the benefit of GNU folk...
694** '_(MSGID)' uses the current locale's message library string for MSGID.
695** The default is to use gettext if available, and use MSGID otherwise.
696*/
697
698#if HAVE_GETTEXT
699#define _(msgid) gettext(msgid)
700#else /* !HAVE_GETTEXT */
701#define _(msgid) msgid
702#endif /* !HAVE_GETTEXT */
703
704#if !defined TZ_DOMAIN && defined HAVE_GETTEXT
705# define TZ_DOMAIN "tz"
706#endif
707
708#if HAVE_INCOMPATIBLE_CTIME_R
709#undef asctime_r
710#undef ctime_r
711char *asctime_r(struct tm const *, char *);
712char *ctime_r(time_t const *, char *);
713#endif /* HAVE_INCOMPATIBLE_CTIME_R */
714
715/* Handy macros that are independent of tzfile implementation. */
716
717#define YEARSPERREPEAT 400 /* years before a Gregorian repeat */
718
719#define SECSPERMIN 60
720#define MINSPERHOUR 60
721#define HOURSPERDAY 24
722#define DAYSPERWEEK 7
723#define DAYSPERNYEAR 365
724#define DAYSPERLYEAR 366
725#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
726#define SECSPERDAY ((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
727#define MONSPERYEAR 12
728
729#define TM_SUNDAY 0
730#define TM_MONDAY 1
731#define TM_TUESDAY 2
732#define TM_WEDNESDAY 3
733#define TM_THURSDAY 4
734#define TM_FRIDAY 5
735#define TM_SATURDAY 6
736
737#define TM_JANUARY 0
738#define TM_FEBRUARY 1
739#define TM_MARCH 2
740#define TM_APRIL 3
741#define TM_MAY 4
742#define TM_JUNE 5
743#define TM_JULY 6
744#define TM_AUGUST 7
745#define TM_SEPTEMBER 8
746#define TM_OCTOBER 9
747#define TM_NOVEMBER 10
748#define TM_DECEMBER 11
749
750#define TM_YEAR_BASE 1900
751
752#define EPOCH_YEAR 1970
753#define EPOCH_WDAY TM_THURSDAY
754
755#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
756
757/*
758** Since everything in isleap is modulo 400 (or a factor of 400), we know that
759** isleap(y) == isleap(y % 400)
760** and so
761** isleap(a + b) == isleap((a + b) % 400)
762** or
763** isleap(a + b) == isleap(a % 400 + b % 400)
764** This is true even if % means modulo rather than Fortran remainder
765** (which is allowed by C89 but not by C99 or later).
766** We use this to avoid addition overflow problems.
767*/
768
769#define isleap_sum(a, b) isleap((a) % 400 + (b) % 400)
770
771
772/*
773** The Gregorian year averages 365.2425 days, which is 31556952 seconds.
774*/
775
776#define AVGSECSPERYEAR 31556952L
777#define SECSPERREPEAT \
778 ((int_fast64_t) YEARSPERREPEAT * (int_fast64_t) AVGSECSPERYEAR)
779#define SECSPERREPEAT_BITS 34 /* ceil(log2(SECSPERREPEAT)) */
780
781#endif /* !defined PRIVATE_H */
782

source code of glibc/timezone/private.h