libs-base/Source/tzdb.h
2021-08-11 08:43:20 +01:00

2292 lines
56 KiB
C

/*
* This is derived from public-domain implementation available from
* NetBSD's libc
* src/lib/libc/time/private.h
* src/lib/libc/time/localtime.c
*/
/* $NetBSD: private.h,v 1.56 2020/05/25 14:52:48 christos Exp $ */
#ifndef __UNCONST
#define __UNCONST(a) ((void *)(unsigned long)(const void *)(a))
#endif
#ifndef _DIAGASSERT
#define _DIAGASSERT(e)
#endif
#ifndef TZDIR
#define TZDIR "/usr/share/zoneinfo"
#endif
/* NetBSD defaults */
#define TM_GMTOFF tm_gmtoff
#define TM_ZONE tm_zone
#define STD_INSPIRED 1
#define HAVE_LONG_DOUBLE 1
/*
** This file is in the public domain, so clarified as of
** 1996-06-05 by Arthur David Olson.
*/
/*
** This header is for use ONLY with the time conversion code.
** There is no guarantee that it will remain unchanged,
** or that it will remain at all.
** Do NOT copy it to any system include directory.
** Thank you!
*/
/*
** zdump has been made independent of the rest of the time
** conversion package to increase confidence in the verification it provides.
** You can use zdump to help in verifying other implementations.
** To do this, compile with -DUSE_LTZ=0 and link without the tz library.
*/
#ifndef USE_LTZ
# define USE_LTZ 1
#endif
/* This string was in the Factory zone through version 2016f. */
#define GRANDPARENTED "Local time zone must be set--see zic manual page"
/*
** Defaults for preprocessor symbols.
** You can override these in your C compiler options, e.g. '-DHAVE_GETTEXT=1'.
*/
#ifndef HAVE_DECL_ASCTIME_R
#define HAVE_DECL_ASCTIME_R 1
#endif
#if !defined HAVE_GENERIC && defined __has_extension
# if __has_extension(c_generic_selections)
# define HAVE_GENERIC 1
# else
# define HAVE_GENERIC 0
# endif
#endif
/* _Generic is buggy in pre-4.9 GCC. */
#if !defined HAVE_GENERIC && defined __GNUC__
# define HAVE_GENERIC (4 < __GNUC__ + (9 <= __GNUC_MINOR__))
#endif
#ifndef HAVE_GENERIC
# define HAVE_GENERIC (201112 <= __STDC_VERSION__)
#endif
#ifndef HAVE_GETTEXT
#define HAVE_GETTEXT 0
#endif /* !defined HAVE_GETTEXT */
#ifndef HAVE_INCOMPATIBLE_CTIME_R
#define HAVE_INCOMPATIBLE_CTIME_R 0
#endif
#ifndef HAVE_LINK
#define HAVE_LINK 1
#endif /* !defined HAVE_LINK */
#ifndef HAVE_POSIX_DECLS
#define HAVE_POSIX_DECLS 1
#endif
#ifndef HAVE_STDBOOL_H
#define HAVE_STDBOOL_H (199901 <= __STDC_VERSION__)
#endif
#ifndef HAVE_STRDUP
#define HAVE_STRDUP 1
#endif
#ifndef HAVE_STRTOLL
#define HAVE_STRTOLL 1
#endif
#ifndef HAVE_SYMLINK
#define HAVE_SYMLINK 1
#endif /* !defined HAVE_SYMLINK */
#ifndef HAVE_SYS_STAT_H
#define HAVE_SYS_STAT_H 1
#endif /* !defined HAVE_SYS_STAT_H */
#ifndef HAVE_SYS_WAIT_H
#define HAVE_SYS_WAIT_H 1
#endif /* !defined HAVE_SYS_WAIT_H */
#ifndef HAVE_UNISTD_H
#define HAVE_UNISTD_H 1
#endif /* !defined HAVE_UNISTD_H */
#ifndef HAVE_UTMPX_H
#define HAVE_UTMPX_H 1
#endif /* !defined HAVE_UTMPX_H */
#ifndef NETBSD_INSPIRED
# define NETBSD_INSPIRED 1
#endif
#if HAVE_INCOMPATIBLE_CTIME_R
#define asctime_r _incompatible_asctime_r
#define ctime_r _incompatible_ctime_r
#endif /* HAVE_INCOMPATIBLE_CTIME_R */
/* Enable tm_gmtoff, tm_zone, and environ on GNUish systems. */
#define _GNU_SOURCE 1
/* Fix asctime_r on Solaris 11. */
#define _POSIX_PTHREAD_SEMANTICS 1
/* Enable strtoimax on pre-C99 Solaris 11. */
#define __EXTENSIONS__ 1
/* To avoid having 'stat' fail unnecessarily with errno == EOVERFLOW,
enable large files on GNUish systems ... */
#ifndef _FILE_OFFSET_BITS
# define _FILE_OFFSET_BITS 64
#endif
/* ... and on AIX ... */
#define _LARGE_FILES 1
/* ... and enable large inode numbers on Mac OS X 10.5 and later. */
#define _DARWIN_USE_64_BIT_INODE 1
/*
** Nested includes
*/
#ifndef __NetBSD__
/* Avoid clashes with NetBSD by renaming NetBSD's declarations.
If defining the 'timezone' variable, avoid a clash with FreeBSD's
'timezone' function by renaming its declaration. */
#define localtime_rz sys_localtime_rz
#define mktime_z sys_mktime_z
#define posix2time_z sys_posix2time_z
#define time2posix_z sys_time2posix_z
#if defined USG_COMPAT && USG_COMPAT == 2
# define timezone sys_timezone
#endif
#define timezone_t sys_timezone_t
#define tzalloc sys_tzalloc
#define tzfree sys_tzfree
#include <time.h>
#undef localtime_rz
#undef mktime_z
#undef posix2time_z
#undef time2posix_z
#if defined USG_COMPAT && USG_COMPAT == 2
# undef timezone
#endif
#undef timezone_t
#undef tzalloc
#undef tzfree
#else
#include "time.h"
#endif
#include <sys/types.h> /* for time_t */
#include <string.h>
#include <limits.h> /* for CHAR_BIT et al. */
#include <stdlib.h>
#include <errno.h>
#ifndef ENAMETOOLONG
# define ENAMETOOLONG EINVAL
#endif
#ifndef ENOTSUP
# define ENOTSUP EINVAL
#endif
#ifndef EOVERFLOW
# define EOVERFLOW EINVAL
#endif
#if HAVE_GETTEXT
#include <libintl.h>
#endif /* HAVE_GETTEXT */
#if HAVE_UNISTD_H
#include <unistd.h> /* for R_OK, and other POSIX goodness */
#endif /* HAVE_UNISTD_H */
#ifndef HAVE_STRFTIME_L
# if _POSIX_VERSION < 200809
# define HAVE_STRFTIME_L 0
# else
# define HAVE_STRFTIME_L 1
# endif
#endif
#ifndef USG_COMPAT
# ifndef _XOPEN_VERSION
# define USG_COMPAT 0
# else
# define USG_COMPAT 1
# endif
#endif
#ifndef HAVE_TZNAME
# if _POSIX_VERSION < 198808 && !USG_COMPAT
# define HAVE_TZNAME 0
# else
# define HAVE_TZNAME 1
# endif
#endif
#ifndef ALTZONE
# if defined __sun || defined _M_XENIX
# define ALTZONE 1
# else
# define ALTZONE 0
# endif
#endif
#ifndef R_OK
#define R_OK 4
#endif /* !defined R_OK */
/* Unlike <ctype.h>'s isdigit, this also works if c < 0 | c > UCHAR_MAX. */
#define is_digit(c) ((unsigned)(c) - '0' <= 9)
/*
** Define HAVE_STDINT_H's default value here, rather than at the
** start, since __GLIBC__ and INTMAX_MAX's values depend on
** previously-included files. glibc 2.1 and Solaris 10 and later have
** stdint.h, even with pre-C99 compilers.
*/
#ifndef HAVE_STDINT_H
#define HAVE_STDINT_H \
(199901 <= __STDC_VERSION__ \
|| 2 < __GLIBC__ + (1 <= __GLIBC_MINOR__) \
|| __CYGWIN__ || INTMAX_MAX)
#endif /* !defined HAVE_STDINT_H */
#if HAVE_STDINT_H
#include <stdint.h>
#endif /* !HAVE_STDINT_H */
#ifndef HAVE_INTTYPES_H
# define HAVE_INTTYPES_H HAVE_STDINT_H
#endif
#if HAVE_INTTYPES_H
# include <inttypes.h>
#endif
/* Pre-C99 GCC compilers define __LONG_LONG_MAX__ instead of LLONG_MAX. */
#ifdef __LONG_LONG_MAX__
# ifndef LLONG_MAX
# define LLONG_MAX __LONG_LONG_MAX__
# endif
# ifndef LLONG_MIN
# define LLONG_MIN (-1 - LLONG_MAX)
# endif
#endif
#ifndef INT_FAST64_MAX
# ifdef LLONG_MAX
typedef long long int_fast64_t;
# define INT_FAST64_MIN LLONG_MIN
# define INT_FAST64_MAX LLONG_MAX
# else
# if LONG_MAX >> 31 < 0xffffffff
Please use a compiler that supports a 64-bit integer type (or wider);
you may need to compile with "-DHAVE_STDINT_H".
# endif
typedef long int_fast64_t;
# define INT_FAST64_MIN LONG_MIN
# define INT_FAST64_MAX LONG_MAX
# endif
#endif
#ifndef PRIdFAST64
# if INT_FAST64_MAX == LLONG_MAX
# define PRIdFAST64 "lld"
# else
# define PRIdFAST64 "ld"
# endif
#endif
#ifndef SCNdFAST64
# define SCNdFAST64 PRIdFAST64
#endif
#ifndef INT_FAST32_MAX
# if INT_MAX >> 31 == 0
typedef long int_fast32_t;
# define INT_FAST32_MAX LONG_MAX
# define INT_FAST32_MIN LONG_MIN
# else
typedef int int_fast32_t;
# define INT_FAST32_MAX INT_MAX
# define INT_FAST32_MIN INT_MIN
# endif
#endif
#ifndef INTMAX_MAX
# ifdef LLONG_MAX
typedef long long intmax_t;
# if HAVE_STRTOLL
# define strtoimax strtoll
# endif
# define INTMAX_MAX LLONG_MAX
# define INTMAX_MIN LLONG_MIN
# else
typedef long intmax_t;
# define INTMAX_MAX LONG_MAX
# define INTMAX_MIN LONG_MIN
# endif
# ifndef strtoimax
# define strtoimax strtol
# endif
#endif
#ifndef PRIdMAX
# if INTMAX_MAX == LLONG_MAX
# define PRIdMAX "lld"
# else
# define PRIdMAX "ld"
# endif
#endif
#ifndef UINT_FAST64_MAX
# if defined ULLONG_MAX || defined __LONG_LONG_MAX__
typedef unsigned long long uint_fast64_t;
# else
# if ULONG_MAX >> 31 >> 1 < 0xffffffff
Please use a compiler that supports a 64-bit integer type (or wider);
you may need to compile with "-DHAVE_STDINT_H".
# endif
typedef unsigned long uint_fast64_t;
# endif
#endif
#ifndef UINTMAX_MAX
# if defined ULLONG_MAX || defined __LONG_LONG_MAX__
typedef unsigned long long uintmax_t;
# else
typedef unsigned long uintmax_t;
# endif
#endif
#ifndef PRIuMAX
# if defined ULLONG_MAX || defined __LONG_LONG_MAX__
# define PRIuMAX "llu"
# else
# define PRIuMAX "lu"
# endif
#endif
#ifndef INT32_MAX
#define INT32_MAX 0x7fffffff
#endif /* !defined INT32_MAX */
#ifndef INT32_MIN
#define INT32_MIN (-1 - INT32_MAX)
#endif /* !defined INT32_MIN */
#ifndef SIZE_MAX
#define SIZE_MAX ((size_t) -1)
#endif
#if 3 <= __GNUC__
# define ATTRIBUTE_CONST __attribute__ ((__const__))
# define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
# define ATTRIBUTE_PURE __attribute__ ((__pure__))
# define ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
#else
# define ATTRIBUTE_CONST /* empty */
# define ATTRIBUTE_MALLOC /* empty */
# define ATTRIBUTE_PURE /* empty */
# define ATTRIBUTE_FORMAT(spec) /* empty */
#endif
#if !defined _Noreturn && __STDC_VERSION__ < 201112
# if 2 < __GNUC__ + (8 <= __GNUC_MINOR__)
# define _Noreturn __attribute__ ((__noreturn__))
# else
# define _Noreturn
# endif
#endif
#if __STDC_VERSION__ < 199901 && !defined restrict
# define restrict /* empty */
#endif
/*
** Workarounds for compilers/systems.
*/
#ifndef EPOCH_LOCAL
# define EPOCH_LOCAL 0
#endif
#ifndef EPOCH_OFFSET
# define EPOCH_OFFSET 0
#endif
#ifndef RESERVE_STD_EXT_IDS
# define RESERVE_STD_EXT_IDS 0
#endif
/* If standard C identifiers with external linkage (e.g., localtime)
are reserved and are not already being renamed anyway, rename them
as if compiling with '-Dtime_tz=time_t'. */
#if !defined time_tz && RESERVE_STD_EXT_IDS && USE_LTZ
# define time_tz time_t
#endif
/*
** Compile with -Dtime_tz=T to build the tz package with a private
** time_t type equivalent to T rather than the system-supplied time_t.
** This debugging feature can test unusual design decisions
** (e.g., time_t wider than 'long', or unsigned time_t) even on
** typical platforms.
*/
#if defined time_tz || EPOCH_LOCAL || EPOCH_OFFSET != 0
# define TZ_TIME_T 1
#else
# define TZ_TIME_T 0
#endif
#if TZ_TIME_T
# ifdef LOCALTIME_IMPLEMENTATION
static time_t sys_time(time_t *x) { return time(x); }
# endif
typedef time_tz tz_time_t;
# undef asctime
# define asctime tz_asctime
# undef asctime_r
# define asctime_r tz_asctime_r
# undef ctime
# define ctime tz_ctime
# undef ctime_r
# define ctime_r tz_ctime_r
# undef difftime
# define difftime tz_difftime
# undef gmtime
# define gmtime tz_gmtime
# undef gmtime_r
# define gmtime_r tz_gmtime_r
# undef localtime
# define localtime tz_localtime
# undef localtime_r
# define localtime_r tz_localtime_r
# undef localtime_rz
# define localtime_rz tz_localtime_rz
# undef mktime
# define mktime tz_mktime
# undef mktime_z
# define mktime_z tz_mktime_z
# undef offtime
# define offtime tz_offtime
# undef posix2time
# define posix2time tz_posix2time
# undef posix2time_z
# define posix2time_z tz_posix2time_z
# undef strftime
# define strftime tz_strftime
# undef time
# define time tz_time
# undef time2posix
# define time2posix tz_time2posix
# undef time2posix_z
# define time2posix_z tz_time2posix_z
# undef time_t
# define time_t tz_time_t
# undef timegm
# define timegm tz_timegm
# undef timelocal
# define timelocal tz_timelocal
# undef timeoff
# define timeoff tz_timeoff
# undef tzalloc
# define tzalloc tz_tzalloc
# undef tzfree
# define tzfree tz_tzfree
# undef tzset
# define tzset tz_tzset
# undef tzsetwall
# define tzsetwall tz_tzsetwall
# if HAVE_STRFTIME_L
# undef strftime_l
# define strftime_l tz_strftime_l
# endif
# if HAVE_TZNAME
# undef tzname
# define tzname tz_tzname
# endif
# if USG_COMPAT
# undef daylight
# define daylight tz_daylight
# undef timezone
# define timezone tz_timezone
# endif
# if ALTZONE
# undef altzone
# define altzone tz_altzone
# endif
char *asctime(struct tm const *);
char *asctime_r(struct tm const *restrict, char *restrict);
char *ctime(time_t const *);
char *ctime_r(time_t const *, char *);
double difftime(time_t, time_t) ATTRIBUTE_CONST;
size_t strftime(char *restrict, size_t, char const *restrict,
struct tm const *restrict);
# if HAVE_STRFTIME_L
size_t strftime_l(char *restrict, size_t, char const *restrict,
struct tm const *restrict, locale_t);
# endif
struct tm *gmtime(time_t const *);
struct tm *gmtime_r(time_t const *restrict, struct tm *restrict);
struct tm *localtime(time_t const *);
struct tm *localtime_r(time_t const *restrict, struct tm *restrict);
time_t mktime(struct tm *);
time_t time(time_t *);
void tzset(void);
#endif
#if !HAVE_DECL_ASCTIME_R && !defined asctime_r
extern char *asctime_r(struct tm const *restrict, char *restrict);
#endif
#ifndef HAVE_DECL_ENVIRON
# if defined environ || defined __USE_GNU
# define HAVE_DECL_ENVIRON 1
# else
# define HAVE_DECL_ENVIRON 0
# endif
#endif
#if !HAVE_DECL_ENVIRON
extern char **environ;
#endif
#if 2 <= HAVE_TZNAME + (TZ_TIME_T || !HAVE_POSIX_DECLS)
extern char *tzname[];
#endif
#if 2 <= USG_COMPAT + (TZ_TIME_T || !HAVE_POSIX_DECLS)
extern long timezone;
extern int daylight;
#endif
#if 2 <= ALTZONE + (TZ_TIME_T || !HAVE_POSIX_DECLS)
extern long altzone;
#endif
/* Infer TM_ZONE on systems where this information is known, but suppress
guessing if NO_TM_ZONE is defined. Similarly for TM_GMTOFF. */
#if (defined __GLIBC__ \
|| defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ \
|| (defined __APPLE__ && defined __MACH__))
# if !defined TM_GMTOFF && !defined NO_TM_GMTOFF
# define TM_GMTOFF tm_gmtoff
# endif
# if !defined TM_ZONE && !defined NO_TM_ZONE
# define TM_ZONE tm_zone
# endif
#endif
/*
** Finally, some convenience items.
*/
#if HAVE_STDBOOL_H
# include <stdbool.h>
#else
# define true 1
# define false 0
# define bool int
#endif
#define TYPE_BIT(type) (sizeof (type) * CHAR_BIT)
#define TYPE_SIGNED(type) (/*CONSTCOND*/((type) -1) < 0)
#define TWOS_COMPLEMENT(t) (/*CONSTCOND*/(t) ~ (t) 0 < 0)
/* Max and min values of the integer type T, of which only the bottom
B bits are used, and where the highest-order used bit is considered
to be a sign bit if T is signed. */
#define MAXVAL(t, b) /*LINTED*/ \
((t) (((t) 1 << ((b) - 1 - TYPE_SIGNED(t))) \
- 1 + ((t) 1 << ((b) - 1 - TYPE_SIGNED(t)))))
#define MINVAL(t, b) \
((t) (TYPE_SIGNED(t) ? - TWOS_COMPLEMENT(t) - MAXVAL(t, b) : 0))
/* The extreme time values, assuming no padding. */
#define TIME_T_MIN_NO_PADDING MINVAL(time_t, TYPE_BIT(time_t))
#define TIME_T_MAX_NO_PADDING MAXVAL(time_t, TYPE_BIT(time_t))
/* The extreme time values. These are macros, not constants, so that
any portability problem occur only when compiling .c files that use
the macros, which is safer for applications that need only zdump and zic.
This implementation assumes no padding if time_t is signed and
either the compiler lacks support for _Generic or time_t is not one
of the standard signed integer types. */
#if HAVE_GENERIC
# define TIME_T_MIN \
_Generic((time_t) 0, \
signed char: SCHAR_MIN, short: SHRT_MIN, \
int: INT_MIN, long: LONG_MIN, long long: LLONG_MIN, \
default: TIME_T_MIN_NO_PADDING)
# define TIME_T_MAX \
(TYPE_SIGNED(time_t) \
? _Generic((time_t) 0, \
signed char: SCHAR_MAX, short: SHRT_MAX, \
int: INT_MAX, long: LONG_MAX, long long: LLONG_MAX, \
default: TIME_T_MAX_NO_PADDING) \
: (time_t) -1)
#else
# define TIME_T_MIN TIME_T_MIN_NO_PADDING
# define TIME_T_MAX TIME_T_MAX_NO_PADDING
#endif
/*
** 302 / 1000 is log10(2.0) rounded up.
** Subtract one for the sign bit if the type is signed;
** add one for integer division truncation;
** add one more for a minus sign if the type is signed.
*/
#define INT_STRLEN_MAXIMUM(type) \
((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + \
1 + TYPE_SIGNED(type))
/*
** INITIALIZE(x)
*/
#if defined(__GNUC__) || defined(__lint__)
# define INITIALIZE(x) ((x) = 0)
#else
# define INITIALIZE(x)
#endif
/* Handy macros that are independent of tzfile implementation. */
#define YEARSPERREPEAT 400 /* years before a Gregorian repeat */
#define SECSPERMIN 60
#define MINSPERHOUR 60
#define HOURSPERDAY 24
#define DAYSPERWEEK 7
#define DAYSPERNYEAR 365
#define DAYSPERLYEAR 366
#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
#ifndef SECSPERDAY
#define SECSPERDAY ((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
#endif
#define MONSPERYEAR 12
#define TM_SUNDAY 0
#define TM_MONDAY 1
#define TM_TUESDAY 2
#define TM_WEDNESDAY 3
#define TM_THURSDAY 4
#define TM_FRIDAY 5
#define TM_SATURDAY 6
#define TM_JANUARY 0
#define TM_FEBRUARY 1
#define TM_MARCH 2
#define TM_APRIL 3
#define TM_MAY 4
#define TM_JUNE 5
#define TM_JULY 6
#define TM_AUGUST 7
#define TM_SEPTEMBER 8
#define TM_OCTOBER 9
#define TM_NOVEMBER 10
#define TM_DECEMBER 11
#define TM_YEAR_BASE 1900
#define EPOCH_YEAR 1970
#define EPOCH_WDAY TM_THURSDAY
#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
/*
** Since everything in isleap is modulo 400 (or a factor of 400), we know that
** isleap(y) == isleap(y % 400)
** and so
** isleap(a + b) == isleap((a + b) % 400)
** or
** isleap(a + b) == isleap(a % 400 + b % 400)
** This is true even if % means modulo rather than Fortran remainder
** (which is allowed by C89 but not by C99 or later).
** We use this to avoid addition overflow problems.
*/
#define isleap_sum(a, b) isleap((a) % 400 + (b) % 400)
/*
** The Gregorian year averages 365.2425 days, which is 31556952 seconds.
*/
#define AVGSECSPERYEAR 31556952L
#define SECSPERREPEAT \
((int_fast64_t) YEARSPERREPEAT * (int_fast64_t) AVGSECSPERYEAR)
#define SECSPERREPEAT_BITS 34 /* ceil(log2(SECSPERREPEAT)) */
/* $NetBSD: localtime.c,v 1.123 2020/05/25 14:52:48 christos Exp $ */
/* Convert timestamp from time_t to struct tm. */
/*
** This file is in the public domain, so clarified as of
** 1996-06-05 by Arthur David Olson.
*/
/*
** Leap second handling from Bradley White.
** POSIX-style TZ environment variable handling from Guy Harris.
*/
#include <fcntl.h>
#ifndef TZ_ABBR_MAX_LEN
#define TZ_ABBR_MAX_LEN 16
#endif /* !defined TZ_ABBR_MAX_LEN */
#ifndef TZ_ABBR_CHAR_SET
#define TZ_ABBR_CHAR_SET \
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._"
#endif /* !defined TZ_ABBR_CHAR_SET */
#ifndef TZ_ABBR_ERR_CHAR
#define TZ_ABBR_ERR_CHAR '_'
#endif /* !defined TZ_ABBR_ERR_CHAR */
/*
** SunOS 4.1.1 headers lack O_BINARY.
*/
#ifdef O_BINARY
#define OPEN_MODE (O_RDONLY | O_BINARY | O_CLOEXEC)
#endif /* defined O_BINARY */
#ifndef O_BINARY
#define OPEN_MODE (O_RDONLY | O_CLOEXEC)
#endif /* !defined O_BINARY */
/*
** The DST rules to use if TZ has no rules and we can't load TZDEFRULES.
** Default to US rules as of 2017-05-07.
** POSIX does not specify the default DST rules;
** for historical reasons, US rules are a common default.
*/
#ifndef TZDEFRULESTRING
#define TZDEFRULESTRING ",M3.2.0,M11.1.0"
#endif
struct _ttinfo { /* time type information */
int_fast32_t tt_utoff; /* UT offset in seconds */
bool tt_isdst; /* used to set tm_isdst */
int tt_desigidx; /* abbreviation list index */
bool tt_ttisstd; /* transition is std time */
bool tt_ttisut; /* transition is UT */
};
struct lsinfo { /* leap second information */
time_t ls_trans; /* transition time */
int_fast64_t ls_corr; /* correction to apply */
};
#define SMALLEST(a, b) (((a) < (b)) ? (a) : (b))
#define BIGGEST(a, b) (((a) > (b)) ? (a) : (b))
#ifdef TZNAME_MAX
#define MY_TZNAME_MAX TZNAME_MAX
#endif /* defined TZNAME_MAX */
#ifndef TZNAME_MAX
#define MY_TZNAME_MAX 255
#endif /* !defined TZNAME_MAX */
/* BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof "GMT"), (2 * (MY_TZNAME_MAX + 1)))
*/
#define TZ_MAX_CHARS_OR_NAMES 512
#define state __state
struct state {
int leapcnt;
int timecnt;
int typecnt;
int charcnt;
bool goback;
bool goahead;
time_t ats[TZ_MAX_TIMES];
unsigned char types[TZ_MAX_TIMES];
struct _ttinfo ttis[TZ_MAX_TYPES];
char chars[TZ_MAX_CHARS_OR_NAMES];
struct lsinfo lsis[TZ_MAX_LEAPS];
/* The time type to use for early times or if no transitions.
It is always zero for recent tzdb releases.
It might be nonzero for data from tzdb 2018e or earlier. */
int defaulttype;
};
enum r_type {
JULIAN_DAY, /* Jn = Julian day */
DAY_OF_YEAR, /* n = day of year */
MONTH_NTH_DAY_OF_WEEK /* Mm.n.d = month, week, day of week */
};
struct rule {
enum r_type r_type; /* type of rule */
int r_day; /* day number of rule */
int r_week; /* week number of rule */
int r_mon; /* month number of rule */
int_fast32_t r_time; /* transition time of rule */
};
static bool increment_overflow(int *, int);
static bool increment_overflow_time(time_t *, int_fast32_t);
static int_fast64_t leapcorr(struct state const *, time_t);
static struct tm *timesub(time_t const *, int_fast32_t, struct state const *,
struct tm *);
static bool typesequiv(struct state const *, int, int);
static bool tzparse(char const *, struct state *, bool);
/* Initialize *S to a value based on UTOFF, ISDST, and DESIGIDX. */
static void
init_ttinfo(struct _ttinfo *s, int_fast32_t utoff, bool isdst, int desigidx)
{
s->tt_utoff = utoff;
s->tt_isdst = isdst;
s->tt_desigidx = desigidx;
s->tt_ttisstd = false;
s->tt_ttisut = false;
}
static int_fast32_t
detzcode(const char *const codep)
{
int_fast32_t result;
int i;
int_fast32_t one = 1;
int_fast32_t halfmaxval = one << (32 - 2);
int_fast32_t maxval = halfmaxval - 1 + halfmaxval;
int_fast32_t minval = -1 - maxval;
result = codep[0] & 0x7f;
for (i = 1; i < 4; ++i)
result = (result << 8) | (codep[i] & 0xff);
if (codep[0] & 0x80) {
/* Do two's-complement negation even on non-two's-complement machines.
If the result would be minval - 1, return minval. */
result -= !TWOS_COMPLEMENT(int_fast32_t) && result != 0;
result += minval;
}
return result;
}
static int_fast64_t
detzcode64(const char *const codep)
{
int_fast64_t result;
int i;
int_fast64_t one = 1;
int_fast64_t halfmaxval = one << (64 - 2);
int_fast64_t maxval = halfmaxval - 1 + halfmaxval;
int_fast64_t minval = -TWOS_COMPLEMENT(int_fast64_t) - maxval;
result = codep[0] & 0x7f;
for (i = 1; i < 8; ++i)
result = (result << 8) | (codep[i] & 0xff);
if (codep[0] & 0x80) {
/* Do two's-complement negation even on non-two's-complement machines.
If the result would be minval - 1, return minval. */
result -= !TWOS_COMPLEMENT(int_fast64_t) && result != 0;
result += minval;
}
return result;
}
static void
scrub_abbrs(struct state *sp)
{
int i;
/*
** First, replace bogus characters.
*/
for (i = 0; i < sp->charcnt; ++i)
if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL)
sp->chars[i] = TZ_ABBR_ERR_CHAR;
/*
** Second, truncate long abbreviations.
*/
for (i = 0; i < sp->typecnt; ++i) {
const struct _ttinfo * const ttisp = &sp->ttis[i];
char *cp = &sp->chars[ttisp->tt_desigidx];
if (strlen(cp) > TZ_ABBR_MAX_LEN &&
strcmp(cp, GRANDPARENTED) != 0)
*(cp + TZ_ABBR_MAX_LEN) = '\0';
}
}
static bool
differ_by_repeat(const time_t t1, const time_t t0)
{
if (TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS)
return 0;
return (int_fast64_t)t1 - (int_fast64_t)t0 == SECSPERREPEAT;
}
union input_buffer {
/* The first part of the buffer, interpreted as a header. */
struct tzhead tzhead;
/* The entire buffer. */
char buf[2 * sizeof(struct tzhead) + 2 * sizeof (struct state)
+ 4 * TZ_MAX_TIMES];
};
/* TZDIR with a trailing '/' rather than a trailing '\0'. */
static char const tzdirslash[sizeof TZDIR] = TZDIR "/";
/* Local storage needed for 'tzloadbody'. */
union local_storage {
/* The results of analyzing the file's contents after it is opened. */
struct file_analysis {
/* The input buffer. */
union input_buffer u;
/* A temporary state used for parsing a TZ string in the file. */
struct state st;
} u;
/* The file name to be opened. */
char fullname[/*CONSTCOND*/BIGGEST(sizeof (struct file_analysis),
sizeof tzdirslash + 1024)];
};
/* Load tz data from the file named NAME into *SP. Read extended
format if DOEXTEND. Use *LSP for temporary storage. Return 0 on
success, an errno value on failure. */
static int
tzloadbody1(char const *name, struct state *sp, bool doextend,
union local_storage *lsp, ssize_t nread)
{
int i;
int stored;
union input_buffer *up = &lsp->u.u;
size_t tzheadsize = sizeof(struct tzhead);
for (stored = 4; stored <= 8; stored *= 2)
{
int_fast32_t ttisstdcnt = detzcode(up->tzhead.tzh_ttisstdcnt);
int_fast32_t ttisutcnt = detzcode(up->tzhead.tzh_ttisutcnt);
int_fast64_t prevtr = 0;
int_fast32_t prevcorr = 0;
int_fast32_t leapcnt = detzcode(up->tzhead.tzh_leapcnt);
int_fast32_t timecnt = detzcode(up->tzhead.tzh_timecnt);
int_fast32_t typecnt = detzcode(up->tzhead.tzh_typecnt);
int_fast32_t charcnt = detzcode(up->tzhead.tzh_charcnt);
char const *p = up->buf + tzheadsize;
/* Although tzfile(5) currently requires typecnt to be nonzero,
support future formats that may allow zero typecnt
in files that have a TZ string and no transitions. */
if (! (0 <= leapcnt && leapcnt < TZ_MAX_LEAPS
&& 0 <= typecnt && typecnt < TZ_MAX_TYPES
&& 0 <= timecnt && timecnt < TZ_MAX_TIMES
&& 0 <= charcnt && charcnt < TZ_MAX_CHARS
&& (ttisstdcnt == typecnt || ttisstdcnt == 0)
&& (ttisutcnt == typecnt || ttisutcnt == 0)))
return EINVAL;
if ((size_t)nread
< (tzheadsize /* struct tzhead */
+ timecnt * stored /* ats */
+ timecnt /* types */
+ typecnt * 6 /* _ttinfos */
+ charcnt /* chars */
+ leapcnt * (stored + 4) /* lsinfos */
+ ttisstdcnt /* ttisstds */
+ ttisutcnt)) /* ttisuts */
return EINVAL;
sp->leapcnt = leapcnt;
sp->timecnt = timecnt;
sp->typecnt = typecnt;
sp->charcnt = charcnt;
/* Read transitions, discarding those out of time_t range.
But pretend the last transition before TIME_T_MIN
occurred at TIME_T_MIN. */
timecnt = 0;
for (i = 0; i < sp->timecnt; ++i) {
int_fast64_t at
= stored == 4 ? detzcode(p) : detzcode64(p);
sp->types[i] = at <= TIME_T_MAX;
if (sp->types[i]) {
time_t attime
= ((TYPE_SIGNED(time_t) ?
at < TIME_T_MIN : at < 0)
? TIME_T_MIN : (time_t)at);
if (timecnt && attime <= sp->ats[timecnt - 1]) {
if (attime < sp->ats[timecnt - 1])
return EINVAL;
sp->types[i - 1] = 0;
timecnt--;
}
sp->ats[timecnt++] = attime;
}
p += stored;
}
timecnt = 0;
for (i = 0; i < sp->timecnt; ++i) {
unsigned char typ = *p++;
if (sp->typecnt <= typ)
return EINVAL;
if (sp->types[i])
sp->types[timecnt++] = typ;
}
sp->timecnt = timecnt;
for (i = 0; i < sp->typecnt; ++i) {
struct _ttinfo * ttisp;
unsigned char isdst, desigidx;
ttisp = &sp->ttis[i];
ttisp->tt_utoff = detzcode(p);
p += 4;
isdst = *p++;
if (! (isdst < 2))
return EINVAL;
ttisp->tt_isdst = isdst;
desigidx = *p++;
if (! (desigidx < sp->charcnt))
return EINVAL;
ttisp->tt_desigidx = desigidx;
}
for (i = 0; i < sp->charcnt; ++i)
sp->chars[i] = *p++;
sp->chars[i] = '\0'; /* ensure '\0' at end */
/* Read leap seconds, discarding those out of time_t range. */
leapcnt = 0;
for (i = 0; i < sp->leapcnt; ++i) {
int_fast64_t tr = stored == 4 ? detzcode(p) :
detzcode64(p);
int_fast32_t corr = detzcode(p + stored);
p += stored + 4;
/* Leap seconds cannot occur before the Epoch. */
if (tr < 0)
return EINVAL;
if (tr <= TIME_T_MAX) {
/* Leap seconds cannot occur more than once per UTC month,
and UTC months are at least 28 days long (minus 1
second for a negative leap second). Each leap second's
correction must differ from the previous one's by 1
second. */
if (tr - prevtr < 28 * SECSPERDAY - 1
|| (corr != prevcorr - 1
&& corr != prevcorr + 1))
return EINVAL;
sp->lsis[leapcnt].ls_trans =
(time_t)(prevtr = tr);
sp->lsis[leapcnt].ls_corr = prevcorr = corr;
leapcnt++;
}
}
sp->leapcnt = leapcnt;
for (i = 0; i < sp->typecnt; ++i) {
struct _ttinfo * ttisp;
ttisp = &sp->ttis[i];
if (ttisstdcnt == 0)
ttisp->tt_ttisstd = false;
else {
if (*p != true && *p != false)
return EINVAL;
ttisp->tt_ttisstd = *p++;
}
}
for (i = 0; i < sp->typecnt; ++i) {
struct _ttinfo * ttisp;
ttisp = &sp->ttis[i];
if (ttisutcnt == 0)
ttisp->tt_ttisut = false;
else {
if (*p != true && *p != false)
return EINVAL;
ttisp->tt_ttisut = *p++;
}
}
/*
** If this is an old file, we're done.
*/
if (up->tzhead.tzh_version[0] == '\0')
break;
nread -= p - up->buf;
memmove(up->buf, p, (size_t)nread);
}
if (doextend && nread > 2
&& up->buf[0] == '\n' && up->buf[nread - 1] == '\n'
&& sp->typecnt + 2 <= TZ_MAX_TYPES)
{
struct state *ts = &lsp->u.st;
up->buf[nread - 1] = '\0';
if (tzparse(&up->buf[1], ts, false))
{
/* Attempt to reuse existing abbreviations.
Without this, America/Anchorage would be right on
the edge after 2037 when TZ_MAX_CHARS is 50, as
sp->charcnt equals 40 (for LMT AST AWT APT AHST
AHDT YST AKDT AKST) and ts->charcnt equals 10
(for AKST AKDT). Reusing means sp->charcnt can
stay 40 in this example. */
int gotabbr = 0;
int charcnt = sp->charcnt;
for (i = 0; i < ts->typecnt; i++) {
char *tsabbr = ts->chars + ts->ttis[i].tt_desigidx;
int j;
for (j = 0; j < charcnt; j++)
if (strcmp(sp->chars + j, tsabbr) == 0) {
ts->ttis[i].tt_desigidx = j;
gotabbr++;
break;
}
if (! (j < charcnt)) {
size_t tsabbrlen = strlen(tsabbr);
if (j + tsabbrlen < TZ_MAX_CHARS) {
strcpy(sp->chars + j, tsabbr);
charcnt = (int_fast32_t)(j + tsabbrlen + 1);
ts->ttis[i].tt_desigidx = j;
gotabbr++;
}
}
}
if (gotabbr == ts->typecnt)
{
sp->charcnt = charcnt;
/* Ignore any trailing, no-op transitions generated
by zic as they don't help here and can run afoul
of bugs in zic 2016j or earlier. */
while (1 < sp->timecnt
&& (sp->types[sp->timecnt - 1]
== sp->types[sp->timecnt - 2]))
sp->timecnt--;
for (i = 0; i < ts->timecnt; i++)
if (sp->timecnt == 0
|| (sp->ats[sp->timecnt - 1]
< ts->ats[i] + leapcorr(sp, ts->ats[i])))
break;
while (i < ts->timecnt
&& sp->timecnt < TZ_MAX_TIMES) {
sp->ats[sp->timecnt] = (time_t)
(ts->ats[i] + leapcorr(sp, ts->ats[i]));
sp->types[sp->timecnt] = (sp->typecnt
+ ts->types[i]);
sp->timecnt++;
i++;
}
for (i = 0; i < ts->typecnt; i++)
sp->ttis[sp->typecnt++] = ts->ttis[i];
}
}
}
if (sp->typecnt == 0)
return EINVAL;
if (sp->timecnt > 1)
{
for (i = 1; i < sp->timecnt; ++i)
{
if (typesequiv(sp, sp->types[i], sp->types[0]))
{
if (differ_by_repeat(sp->ats[i], sp->ats[0]))
{
sp->goback = true;
break;
}
}
}
for (i = sp->timecnt - 2; i >= 0; --i)
{
if (typesequiv(sp, sp->types[sp->timecnt - 1], sp->types[i]))
{
if (differ_by_repeat(sp->ats[sp->timecnt - 1], sp->ats[i]))
{
sp->goahead = true;
break;
}
}
}
}
/* Infer sp->defaulttype from the data. Although this default
type is always zero for data from recent tzdb releases,
things are trickier for data from tzdb 2018e or earlier.
The first set of heuristics work around bugs in 32-bit data
generated by tzdb 2013c or earlier. The workaround is for
zones like Australia/Macquarie where timestamps before the
first transition have a time type that is not the earliest
standard-time type. See:
https://mm.icann.org/pipermail/tz/2013-May/019368.html */
/*
** If type 0 is unused in transitions,
** it's the type to use for early times.
*/
for (i = 0; i < sp->timecnt; ++i)
if (sp->types[i] == 0)
break;
i = i < sp->timecnt ? -1 : 0;
/*
** Absent the above,
** if there are transition times
** and the first transition is to a daylight time
** find the standard type less than and closest to
** the type of the first transition.
*/
if (i < 0 && sp->timecnt > 0 && sp->ttis[sp->types[0]].tt_isdst) {
i = sp->types[0];
while (--i >= 0)
if (!sp->ttis[i].tt_isdst)
break;
}
/* The next heuristics are for data generated by tzdb 2018e or
earlier, for zones like EST5EDT where the first transition
is to DST. */
/*
** If no result yet, find the first standard type.
** If there is none, punt to type zero.
*/
if (i < 0) {
i = 0;
while (sp->ttis[i].tt_isdst)
if (++i >= sp->typecnt) {
i = 0;
break;
}
}
/* A simple 'sp->defaulttype = 0;' would suffice here if we
didn't have to worry about 2018e-or-earlier data. Even
simpler would be to remove the defaulttype member and just
use 0 in its place. */
sp->defaulttype = i;
return 0;
}
static int
tzloadbody(char const *name, struct state *sp, bool doextend,
union local_storage *lsp)
{
int fid;
ssize_t nread;
bool doaccess;
union input_buffer *up = &lsp->u.u;
size_t tzheadsize = sizeof(struct tzhead);
sp->goback = sp->goahead = false;
if (! name) {
name = TZDEFAULT;
if (! name)
return EINVAL;
}
if (name[0] == ':')
++name;
doaccess = name[0] == '/';
if (!doaccess) {
char const *dot;
size_t namelen = strlen(name);
if (sizeof lsp->fullname - sizeof tzdirslash <= namelen)
return ENAMETOOLONG;
/* Create a string "TZDIR/NAME". Using sprintf here
would pull in stdio (and would fail if the
resulting string length exceeded INT_MAX!). */
memcpy(lsp->fullname, tzdirslash, sizeof tzdirslash);
strcpy(lsp->fullname + sizeof tzdirslash, name);
/* Set doaccess if NAME contains a ".." file name
component, as such a name could read a file outside
the TZDIR virtual subtree. */
for (dot = name; (dot = strchr(dot, '.')) != NULL; dot++)
if ((dot == name || dot[-1] == '/') && dot[1] == '.'
&& (dot[2] == '/' || !dot[2])) {
doaccess = true;
break;
}
name = lsp->fullname;
}
if (doaccess && access(name, R_OK) != 0)
return errno;
fid = open(name, OPEN_MODE);
if (fid < 0)
return errno;
nread = read(fid, up->buf, sizeof up->buf);
if (nread < (ssize_t)tzheadsize) {
int err = nread < 0 ? errno : EINVAL;
close(fid);
return err;
}
if (close(fid) < 0)
return errno;
return tzloadbody1(name, sp, doextend, lsp, nread);
}
/* Load tz data from the file named NAME into *SP. Read extended
format if DOEXTEND. Return 0 on success, an errno value on failure. */
static int
tzload(char const *name, struct state *sp, bool doextend)
{
union local_storage *lsp = malloc(sizeof *lsp);
if (!lsp)
{
return errno;
}
else
{
int err = tzloadbody(name, sp, doextend, lsp);
free(lsp);
return err;
}
}
static bool
typesequiv(const struct state *sp, int a, int b)
{
bool result;
if (sp == NULL ||
a < 0 || a >= sp->typecnt ||
b < 0 || b >= sp->typecnt)
result = false;
else {
const struct _ttinfo * ap = &sp->ttis[a];
const struct _ttinfo * bp = &sp->ttis[b];
result = (ap->tt_utoff == bp->tt_utoff
&& ap->tt_isdst == bp->tt_isdst
&& ap->tt_ttisstd == bp->tt_ttisstd
&& ap->tt_ttisut == bp->tt_ttisut
&& (strcmp(&sp->chars[ap->tt_desigidx],
&sp->chars[bp->tt_desigidx])
== 0));
}
return result;
}
static const int mon_lengths[2][MONSPERYEAR] = {
{ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
{ 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
};
static const int year_lengths[2] = {
DAYSPERNYEAR, DAYSPERLYEAR
};
/*
** Given a pointer into a timezone string, scan until a character that is not
** a valid character in a time zone abbreviation is found.
** Return a pointer to that character.
*/
static ATTRIBUTE_PURE const char *
getzname(const char *strp)
{
char c;
while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' &&
c != '+')
++strp;
return strp;
}
/*
** Given a pointer into an extended timezone string, scan until the ending
** delimiter of the time zone abbreviation is located.
** Return a pointer to the delimiter.
**
** As with getzname above, the legal character set is actually quite
** restricted, with other characters producing undefined results.
** We don't do any checking here; checking is done later in common-case code.
*/
static ATTRIBUTE_PURE const char *
getqzname(const char *strp, const int delim)
{
int c;
while ((c = *strp) != '\0' && c != delim)
++strp;
return strp;
}
/*
** Given a pointer into a timezone string, extract a number from that string.
** Check that the number is within a specified range; if it is not, return
** NULL.
** Otherwise, return a pointer to the first character not part of the number.
*/
static const char *
getnum(const char *strp, int *const nump, const int min, const int max)
{
char c;
int num;
if (strp == NULL || !is_digit(c = *strp)) {
errno = EINVAL;
return NULL;
}
num = 0;
do {
num = num * 10 + (c - '0');
if (num > max) {
errno = EOVERFLOW;
return NULL; /* illegal value */
}
c = *++strp;
} while (is_digit(c));
if (num < min) {
errno = EINVAL;
return NULL; /* illegal value */
}
*nump = num;
return strp;
}
/*
** Given a pointer into a timezone string, extract a number of seconds,
** in hh[:mm[:ss]] form, from the string.
** If any error occurs, return NULL.
** Otherwise, return a pointer to the first character not part of the number
** of seconds.
*/
static const char *
getsecs(const char *strp, int_fast32_t *const secsp)
{
int num;
/*
** 'HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like
** "M10.4.6/26", which does not conform to Posix,
** but which specifies the equivalent of
** "02:00 on the first Sunday on or after 23 Oct".
*/
strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1);
if (strp == NULL)
return NULL;
*secsp = num * (int_fast32_t) SECSPERHOUR;
if (*strp == ':') {
++strp;
strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
if (strp == NULL)
return NULL;
*secsp += num * SECSPERMIN;
if (*strp == ':') {
++strp;
/* 'SECSPERMIN' allows for leap seconds. */
strp = getnum(strp, &num, 0, SECSPERMIN);
if (strp == NULL)
return NULL;
*secsp += num;
}
}
return strp;
}
/*
** Given a pointer into a timezone string, extract an offset, in
** [+-]hh[:mm[:ss]] form, from the string.
** If any error occurs, return NULL.
** Otherwise, return a pointer to the first character not part of the time.
*/
static const char *
getoffset(const char *strp, int_fast32_t *const offsetp)
{
bool neg = false;
if (*strp == '-') {
neg = true;
++strp;
} else if (*strp == '+')
++strp;
strp = getsecs(strp, offsetp);
if (strp == NULL)
return NULL; /* illegal time */
if (neg)
*offsetp = -*offsetp;
return strp;
}
/*
** Given a pointer into a timezone string, extract a rule in the form
** date[/time]. See POSIX section 8 for the format of "date" and "time".
** If a valid rule is not found, return NULL.
** Otherwise, return a pointer to the first character not part of the rule.
*/
static const char *
getrule(const char *strp, struct rule *const rulep)
{
if (*strp == 'J') {
/*
** Julian day.
*/
rulep->r_type = JULIAN_DAY;
++strp;
strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
} else if (*strp == 'M') {
/*
** Month, week, day.
*/
rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
++strp;
strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
if (strp == NULL)
return NULL;
if (*strp++ != '.')
return NULL;
strp = getnum(strp, &rulep->r_week, 1, 5);
if (strp == NULL)
return NULL;
if (*strp++ != '.')
return NULL;
strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
} else if (is_digit(*strp)) {
/*
** Day of year.
*/
rulep->r_type = DAY_OF_YEAR;
strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
} else return NULL; /* invalid format */
if (strp == NULL)
return NULL;
if (*strp == '/') {
/*
** Time specified.
*/
++strp;
strp = getoffset(strp, &rulep->r_time);
} else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */
return strp;
}
/*
** Given a year, a rule, and the offset from UT at the time that rule takes
** effect, calculate the year-relative time that rule takes effect.
*/
static int_fast32_t
transtime(const int year, const struct rule *const rulep,
const int_fast32_t offset)
{
bool leapyear;
int_fast32_t value;
int i;
int d, m1, yy0, yy1, yy2, dow;
INITIALIZE(value);
leapyear = isleap(year);
switch (rulep->r_type) {
case JULIAN_DAY:
/*
** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
** years.
** In non-leap years, or if the day number is 59 or less, just
** add SECSPERDAY times the day number-1 to the time of
** January 1, midnight, to get the day.
*/
value = (rulep->r_day - 1) * SECSPERDAY;
if (leapyear && rulep->r_day >= 60)
value += SECSPERDAY;
break;
case DAY_OF_YEAR:
/*
** n - day of year.
** Just add SECSPERDAY times the day number to the time of
** January 1, midnight, to get the day.
*/
value = rulep->r_day * SECSPERDAY;
break;
case MONTH_NTH_DAY_OF_WEEK:
/*
** Mm.n.d - nth "dth day" of month m.
*/
/*
** Use Zeller's Congruence to get day-of-week of first day of
** month.
*/
m1 = (rulep->r_mon + 9) % 12 + 1;
yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
yy1 = yy0 / 100;
yy2 = yy0 % 100;
dow = ((26 * m1 - 2) / 10 +
1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
if (dow < 0)
dow += DAYSPERWEEK;
/*
** "dow" is the day-of-week of the first day of the month. Get
** the day-of-month (zero-origin) of the first "dow" day of the
** month.
*/
d = rulep->r_day - dow;
if (d < 0)
d += DAYSPERWEEK;
for (i = 1; i < rulep->r_week; ++i) {
if (d + DAYSPERWEEK >=
mon_lengths[leapyear][rulep->r_mon - 1])
break;
d += DAYSPERWEEK;
}
/*
** "d" is the day-of-month (zero-origin) of the day we want.
*/
value = d * SECSPERDAY;
for (i = 0; i < rulep->r_mon - 1; ++i)
value += mon_lengths[leapyear][i] * SECSPERDAY;
break;
}
/*
** "value" is the year-relative time of 00:00:00 UT on the day in
** question. To get the year-relative time of the specified local
** time on that day, add the transition time and the current offset
** from UT.
*/
return value + rulep->r_time + offset;
}
/*
** Given a POSIX section 8-style TZ string, fill in the rule tables as
** appropriate.
*/
//#define DEB(X) fprintf(stderr, "tzparse %d\n", X);
#define DEB(X)
static bool
tzparse(const char *name, struct state *sp, bool lastditch)
{
const char *stdname;
const char *dstname;
size_t stdlen;
size_t dstlen;
size_t charcnt;
int_fast32_t stdoffset;
int_fast32_t dstoffset;
char *cp;
bool load_ok;
DEB(1)
dstname = NULL; /* XXX gcc */
stdname = name;
if (lastditch) {
stdlen = sizeof "GMT" - 1;
name += stdlen;
stdoffset = 0;
} else {
if (*name == '<') {
name++;
stdname = name;
name = getqzname(name, '>');
if (*name != '>')
{
DEB(2)
return false;
}
stdlen = name - stdname;
name++;
} else {
name = getzname(name);
stdlen = name - stdname;
}
if (!stdlen)
{
DEB(3)
return false;
}
name = getoffset(name, &stdoffset);
if (name == NULL)
{
DEB(4)
return false;
}
}
charcnt = stdlen + 1;
if (sizeof sp->chars < charcnt)
{
DEB(5)
return false;
}
load_ok = tzload(TZDEFRULES, sp, false) == 0;
if (!load_ok)
sp->leapcnt = 0; /* so, we're off a little */
if (*name != '\0') {
if (*name == '<') {
dstname = ++name;
name = getqzname(name, '>');
if (*name != '>')
{
DEB(6)
return false;
}
dstlen = name - dstname;
name++;
} else {
dstname = name;
name = getzname(name);
dstlen = name - dstname; /* length of DST abbr. */
}
if (!dstlen)
{
DEB(7)
return false;
}
charcnt += dstlen + 1;
if (sizeof sp->chars < charcnt)
{
DEB(8)
return false;
}
if (*name != '\0' && *name != ',' && *name != ';') {
name = getoffset(name, &dstoffset);
if (name == NULL)
{
DEB(9)
return false;
}
} else dstoffset = stdoffset - SECSPERHOUR;
if (*name == '\0' && !load_ok)
name = TZDEFRULESTRING;
if (*name == ',' || *name == ';') {
struct rule start;
struct rule end;
int year;
int yearlim;
int timecnt;
time_t janfirst;
int_fast32_t janoffset = 0;
int yearbeg;
++name;
if ((name = getrule(name, &start)) == NULL)
{
DEB(10)
return false;
}
if (*name++ != ',')
{
DEB(11)
return false;
}
if ((name = getrule(name, &end)) == NULL)
{
DEB(12)
return false;
}
if (*name != '\0')
{
DEB(13)
return false;
}
sp->typecnt = 2; /* standard time and DST */
/*
** Two transitions per year, from EPOCH_YEAR forward.
*/
init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
init_ttinfo(&sp->ttis[1], -dstoffset, true,
(int)(stdlen + 1));
sp->defaulttype = 0;
timecnt = 0;
janfirst = 0;
yearbeg = EPOCH_YEAR;
do {
int_fast32_t yearsecs
= year_lengths[isleap(yearbeg - 1)] * SECSPERDAY;
yearbeg--;
if (increment_overflow_time(&janfirst, -yearsecs)) {
janoffset = -yearsecs;
break;
}
} while (EPOCH_YEAR - YEARSPERREPEAT / 2 < yearbeg);
yearlim = yearbeg + YEARSPERREPEAT + 1;
for (year = yearbeg; year < yearlim; year++) {
int_fast32_t
starttime = transtime(year, &start, stdoffset),
endtime = transtime(year, &end, dstoffset);
int_fast32_t
yearsecs = (year_lengths[isleap(year)]
* SECSPERDAY);
bool reversed = endtime < starttime;
if (reversed) {
int_fast32_t swap = starttime;
starttime = endtime;
endtime = swap;
}
if (reversed
|| (starttime < endtime
&& (endtime - starttime
< (yearsecs
+ (stdoffset - dstoffset))))) {
if (TZ_MAX_TIMES - 2 < timecnt)
break;
sp->ats[timecnt] = janfirst;
if (! increment_overflow_time
(&sp->ats[timecnt],
janoffset + starttime))
sp->types[timecnt++] = !reversed;
sp->ats[timecnt] = janfirst;
if (! increment_overflow_time
(&sp->ats[timecnt],
janoffset + endtime)) {
sp->types[timecnt++] = reversed;
yearlim = year + YEARSPERREPEAT + 1;
}
}
if (increment_overflow_time
(&janfirst, janoffset + yearsecs))
break;
janoffset = 0;
}
sp->timecnt = timecnt;
if (! timecnt) {
sp->ttis[0] = sp->ttis[1];
sp->typecnt = 1; /* Perpetual DST. */
} else if (YEARSPERREPEAT < year - yearbeg)
sp->goback = sp->goahead = true;
} else {
int_fast32_t theirstdoffset;
int_fast32_t theirdstoffset;
int_fast32_t theiroffset;
bool isdst;
int i;
int j;
if (*name != '\0')
{
DEB(14)
return false;
}
/*
** Initial values of theirstdoffset and theirdstoffset.
*/
theirstdoffset = 0;
for (i = 0; i < sp->timecnt; ++i) {
j = sp->types[i];
if (!sp->ttis[j].tt_isdst) {
theirstdoffset =
- sp->ttis[j].tt_utoff;
break;
}
}
theirdstoffset = 0;
for (i = 0; i < sp->timecnt; ++i) {
j = sp->types[i];
if (sp->ttis[j].tt_isdst) {
theirdstoffset =
- sp->ttis[j].tt_utoff;
break;
}
}
/*
** Initially we're assumed to be in standard time.
*/
isdst = false;
theiroffset = theirstdoffset;
/*
** Now juggle transition times and types
** tracking offsets as you do.
*/
for (i = 0; i < sp->timecnt; ++i) {
j = sp->types[i];
sp->types[i] = sp->ttis[j].tt_isdst;
if (sp->ttis[j].tt_ttisut) {
/* No adjustment to transition time */
} else {
/*
** If daylight saving time is in
** effect, and the transition time was
** not specified as standard time, add
** the daylight saving time offset to
** the transition time; otherwise, add
** the standard time offset to the
** transition time.
*/
/*
** Transitions from DST to DDST
** will effectively disappear since
** POSIX provides for only one DST
** offset.
*/
if (isdst && !sp->ttis[j].tt_ttisstd) {
sp->ats[i] += (time_t)
(dstoffset - theirdstoffset);
} else {
sp->ats[i] += (time_t)
(stdoffset - theirstdoffset);
}
}
theiroffset = -sp->ttis[j].tt_utoff;
if (sp->ttis[j].tt_isdst)
theirstdoffset = theiroffset;
else theirdstoffset = theiroffset;
}
/*
** Finally, fill in ttis.
*/
init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
init_ttinfo(&sp->ttis[1], -dstoffset, true,
(int)(stdlen + 1));
sp->typecnt = 2;
sp->defaulttype = 0;
}
} else {
dstlen = 0;
sp->typecnt = 1; /* only standard time */
sp->timecnt = 0;
init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
init_ttinfo(&sp->ttis[1], 0, false, 0);
sp->defaulttype = 0;
}
sp->charcnt = (int)charcnt;
cp = sp->chars;
(void) memcpy(cp, stdname, stdlen);
cp += stdlen;
*cp++ = '\0';
if (dstlen != 0) {
(void) memcpy(cp, dstname, dstlen);
*(cp + dstlen) = '\0';
}
DEB(15);
return true;
}
/*
** The easy way to behave "as if no library function calls" localtime
** is to not call it, so we drop its guts into "localsub", which can be
** freely called. (And no, the PANS doesn't require the above behavior,
** but it *is* desirable.)
**
** If successful and SETNAME is nonzero,
** set the applicable parts of tzname, timezone and altzone;
** however, it's OK to omit this step if the timezone is POSIX-compatible,
** since in that case tzset should have already done this step correctly.
** SETNAME's type is intfast32_t for compatibility with gmtsub,
** but it is actually a boolean and its value should be 0 or 1.
*/
/*ARGSUSED*/
static struct tm *
localsub(struct state const *sp, time_t const *timep, int_fast32_t setname,
struct tm *const tmp)
{
const struct _ttinfo *ttisp;
int i;
struct tm *result;
const time_t t = *timep;
#if 0
if (sp == NULL) {
/* Don't bother to set tzname etc.; tzset has already done it. */
return gmtsub(gmtptr, timep, 0, tmp);
}
#endif
if ((sp->goback && t < sp->ats[0])
|| (sp->goahead && t > sp->ats[sp->timecnt - 1]))
{
time_t newt = t;
time_t seconds;
time_t years;
if (t < sp->ats[0])
seconds = sp->ats[0] - t;
else
seconds = t - sp->ats[sp->timecnt - 1];
--seconds;
years = (time_t)((seconds / SECSPERREPEAT + 1) * YEARSPERREPEAT);
seconds = (time_t)(years * AVGSECSPERYEAR);
if (t < sp->ats[0])
newt += seconds;
else
newt -= seconds;
if (newt < sp->ats[0] || newt > sp->ats[sp->timecnt - 1])
{
errno = EINVAL;
return NULL; /* "cannot happen" */
}
result = localsub(sp, &newt, setname, tmp);
if (result)
{
int_fast64_t newy;
newy = result->tm_year;
if (t < sp->ats[0])
{
newy -= years;
}
else
{
newy += years;
}
if (! (INT_MIN <= newy && newy <= INT_MAX))
{
errno = EOVERFLOW;
return NULL;
}
result->tm_year = (int)newy;
}
return result;
}
if (sp->timecnt == 0 || t < sp->ats[0])
{
i = sp->defaulttype;
}
else
{
int lo = 1;
int hi = sp->timecnt;
while (lo < hi)
{
int mid = (lo + hi) / 2;
if (t < sp->ats[mid])
{
hi = mid;
}
else
{
lo = mid + 1;
}
}
i = (int) sp->types[lo - 1];
}
ttisp = &sp->ttis[i];
/*
** To get (wrong) behavior that's compatible with System V Release 2.0
** you'd replace the statement below with
** t += ttisp->tt_utoff;
** timesub(&t, 0L, sp, tmp);
*/
result = timesub(&t, ttisp->tt_utoff, sp, tmp);
if (result)
{
result->tm_isdst = ttisp->tt_isdst;
#ifdef TM_ZONE
result->TM_ZONE = __UNCONST(&sp->chars[ttisp->tt_desigidx]);
#endif /* defined TM_ZONE */
}
return result;
}
/*
** Return the number of leap years through the end of the given year
** where, to make the math easy, the answer for year zero is defined as zero.
*/
static int
leaps_thru_end_of_nonneg(int y)
{
return y / 4 - y / 100 + y / 400;
}
static int ATTRIBUTE_PURE
leaps_thru_end_of(const int y)
{
return (y < 0
? -1 - leaps_thru_end_of_nonneg(-1 - y)
: leaps_thru_end_of_nonneg(y));
}
static struct tm *
timesub(const time_t *timep, int_fast32_t offset,
const struct state *sp, struct tm *tmp)
{
const struct lsinfo * lp;
time_t tdays;
int idays; /* unsigned would be so 2003 */
int_fast64_t rem;
int y;
const int * ip;
int_fast64_t corr;
int hit;
int i;
corr = 0;
hit = false;
i = (sp == NULL) ? 0 : sp->leapcnt;
while (--i >= 0) {
lp = &sp->lsis[i];
if (*timep >= lp->ls_trans) {
corr = lp->ls_corr;
hit = (*timep == lp->ls_trans
&& (i == 0 ? 0 : lp[-1].ls_corr) < corr);
break;
}
}
y = EPOCH_YEAR;
tdays = (time_t)(*timep / SECSPERDAY);
rem = *timep % SECSPERDAY;
while (tdays < 0 || tdays >= year_lengths[isleap(y)]) {
int newy;
time_t tdelta;
int idelta;
int leapdays;
tdelta = tdays / DAYSPERLYEAR;
if (! ((! TYPE_SIGNED(time_t) || INT_MIN <= tdelta)
&& tdelta <= INT_MAX))
goto out_of_range;
_DIAGASSERT(__type_fit(int, tdelta));
idelta = (int)tdelta;
if (idelta == 0)
idelta = (tdays < 0) ? -1 : 1;
newy = y;
if (increment_overflow(&newy, idelta))
goto out_of_range;
leapdays = leaps_thru_end_of(newy - 1) -
leaps_thru_end_of(y - 1);
tdays -= ((time_t) newy - y) * DAYSPERNYEAR;
tdays -= leapdays;
y = newy;
}
/*
** Given the range, we can now fearlessly cast...
*/
idays = (int) tdays;
rem += offset - corr;
while (rem < 0) {
rem += SECSPERDAY;
--idays;
}
while (rem >= SECSPERDAY) {
rem -= SECSPERDAY;
++idays;
}
while (idays < 0) {
if (increment_overflow(&y, -1))
goto out_of_range;
idays += year_lengths[isleap(y)];
}
while (idays >= year_lengths[isleap(y)]) {
idays -= year_lengths[isleap(y)];
if (increment_overflow(&y, 1))
goto out_of_range;
}
tmp->tm_year = y;
if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE))
goto out_of_range;
tmp->tm_yday = idays;
/*
** The "extra" mods below avoid overflow problems.
*/
tmp->tm_wday = EPOCH_WDAY +
((y - EPOCH_YEAR) % DAYSPERWEEK) *
(DAYSPERNYEAR % DAYSPERWEEK) +
leaps_thru_end_of(y - 1) -
leaps_thru_end_of(EPOCH_YEAR - 1) +
idays;
tmp->tm_wday %= DAYSPERWEEK;
if (tmp->tm_wday < 0)
tmp->tm_wday += DAYSPERWEEK;
tmp->tm_hour = (int) (rem / SECSPERHOUR);
rem %= SECSPERHOUR;
tmp->tm_min = (int) (rem / SECSPERMIN);
/*
** A positive leap second requires a special
** representation. This uses "... ??:59:60" et seq.
*/
tmp->tm_sec = (int) (rem % SECSPERMIN) + hit;
ip = mon_lengths[isleap(y)];
for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon))
idays -= ip[tmp->tm_mon];
tmp->tm_mday = (int) (idays + 1);
tmp->tm_isdst = 0;
#ifdef TM_GMTOFF
tmp->TM_GMTOFF = offset;
#endif /* defined TM_GMTOFF */
return tmp;
out_of_range:
errno = EOVERFLOW;
return NULL;
}
#ifndef WRONG
#define WRONG ((time_t)-1)
#endif /* !defined WRONG */
/*
** Normalize logic courtesy Paul Eggert.
*/
static bool
increment_overflow(int *ip, int j)
{
int const i = *ip;
/*
** If i >= 0 there can only be overflow if i + j > INT_MAX
** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow.
** If i < 0 there can only be overflow if i + j < INT_MIN
** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow.
*/
if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i))
return true;
*ip += j;
return false;
}
static bool
increment_overflow_time(time_t *tp, int_fast32_t j)
{
/*
** This is like
** 'if (! (TIME_T_MIN <= *tp + j && *tp + j <= TIME_T_MAX)) ...',
** except that it does the right thing even if *tp + j would overflow.
*/
if (! (j < 0
? (TYPE_SIGNED(time_t) ? TIME_T_MIN - j <= *tp : -1 - j < *tp)
: *tp <= TIME_T_MAX - j))
return true;
*tp += j;
return false;
}
static int_fast64_t
leapcorr(struct state const *sp, time_t t)
{
struct lsinfo const * lp;
int i;
i = sp->leapcnt;
while (--i >= 0) {
lp = &sp->lsis[i];
if (t >= lp->ls_trans)
return lp->ls_corr;
}
return 0;
}