742 lines
23 KiB
C
742 lines
23 KiB
C
/* Convert a 'struct tm' to a time_t value.
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Copyright (C) 1993-2015 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Paul Eggert <eggert@twinsun.com>.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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||
License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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||
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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/* Define this to have a standalone program to test this implementation of
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mktime. */
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/* #define DEBUG 1 */
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#ifndef _LIBC
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# include <config.h>
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#endif
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/* Assume that leap seconds are possible, unless told otherwise.
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If the host has a 'zic' command with a '-L leapsecondfilename' option,
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then it supports leap seconds; otherwise it probably doesn't. */
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#ifndef LEAP_SECONDS_POSSIBLE
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# define LEAP_SECONDS_POSSIBLE 1
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#endif
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#include <time.h>
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#include <limits.h>
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#include <string.h> /* For the real memcpy prototype. */
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#if defined DEBUG && DEBUG
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# include <stdio.h>
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# include <stdlib.h>
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/* Make it work even if the system's libc has its own mktime routine. */
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# undef mktime
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# define mktime my_mktime
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#endif /* DEBUG */
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/* Some of the code in this file assumes that signed integer overflow
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silently wraps around. This assumption can't easily be programmed
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around, nor can it be checked for portably at compile-time or
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easily eliminated at run-time.
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Define WRAPV to 1 if the assumption is valid and if
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#pragma GCC optimize ("wrapv")
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does not trigger GCC bug 51793
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<http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51793>.
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Otherwise, define it to 0; this forces the use of slower code that,
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while not guaranteed by the C Standard, works on all production
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platforms that we know about. */
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#ifndef WRAPV
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# if (((__GNUC__ == 4 && 4 <= __GNUC_MINOR__) || 4 < __GNUC__) \
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&& defined __GLIBC__)
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# pragma GCC optimize ("wrapv")
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# define WRAPV 1
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# else
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# define WRAPV 0
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# endif
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#endif
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/* Verify a requirement at compile-time (unlike assert, which is runtime). */
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#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
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/* A signed type that is at least one bit wider than int. */
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#if INT_MAX <= LONG_MAX / 2
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typedef long int long_int;
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#else
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typedef long long int long_int;
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#endif
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verify (long_int_is_wide_enough, INT_MAX == INT_MAX * (long_int) 2 / 2);
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/* Shift A right by B bits portably, by dividing A by 2**B and
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truncating towards minus infinity. A and B should be free of side
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effects, and B should be in the range 0 <= B <= INT_BITS - 2, where
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INT_BITS is the number of useful bits in an int. GNU code can
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assume that INT_BITS is at least 32.
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ISO C99 says that A >> B is implementation-defined if A < 0. Some
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implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift
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right in the usual way when A < 0, so SHR falls back on division if
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ordinary A >> B doesn't seem to be the usual signed shift. */
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#define SHR(a, b) \
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((-1 >> 1 == -1 \
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&& (long_int) -1 >> 1 == -1 \
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&& ((time_t) -1 >> 1 == -1 || ! TYPE_SIGNED (time_t))) \
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? (a) >> (b) \
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: (a) / (1 << (b)) - ((a) % (1 << (b)) < 0))
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/* The extra casts in the following macros work around compiler bugs,
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e.g., in Cray C 5.0.3.0. */
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/* True if the arithmetic type T is an integer type. bool counts as
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an integer. */
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#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
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/* True if negative values of the signed integer type T use two's
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complement, or if T is an unsigned integer type. */
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#define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
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/* True if the arithmetic type T is signed. */
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#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
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/* The maximum and minimum values for the integer type T. These
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macros have undefined behavior if T is signed and has padding bits.
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If this is a problem for you, please let us know how to fix it for
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your host. */
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#define TYPE_MINIMUM(t) \
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((t) (! TYPE_SIGNED (t) \
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? (t) 0 \
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: ~ TYPE_MAXIMUM (t)))
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#define TYPE_MAXIMUM(t) \
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((t) (! TYPE_SIGNED (t) \
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? (t) -1 \
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: ((((t) 1 << (sizeof (t) * CHAR_BIT - 2)) - 1) * 2 + 1)))
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#ifndef TIME_T_MIN
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# define TIME_T_MIN TYPE_MINIMUM (time_t)
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#endif
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#ifndef TIME_T_MAX
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# define TIME_T_MAX TYPE_MAXIMUM (time_t)
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#endif
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#define TIME_T_MIDPOINT (SHR (TIME_T_MIN + TIME_T_MAX, 1) + 1)
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verify (time_t_is_integer, TYPE_IS_INTEGER (time_t));
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verify (twos_complement_arithmetic,
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(TYPE_TWOS_COMPLEMENT (int)
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&& TYPE_TWOS_COMPLEMENT (long_int)
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&& TYPE_TWOS_COMPLEMENT (time_t)));
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#define EPOCH_YEAR 1970
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#define TM_YEAR_BASE 1900
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verify (base_year_is_a_multiple_of_100, TM_YEAR_BASE % 100 == 0);
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/* Return 1 if YEAR + TM_YEAR_BASE is a leap year. */
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static int
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leapyear (long_int year)
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{
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/* Don't add YEAR to TM_YEAR_BASE, as that might overflow.
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Also, work even if YEAR is negative. */
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return
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((year & 3) == 0
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&& (year % 100 != 0
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|| ((year / 100) & 3) == (- (TM_YEAR_BASE / 100) & 3)));
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}
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/* How many days come before each month (0-12). */
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#ifndef _LIBC
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static
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#endif
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const unsigned short int __mon_yday[2][13] =
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{
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/* Normal years. */
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{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
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/* Leap years. */
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{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
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};
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#ifndef _LIBC
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/* Portable standalone applications should supply a <time.h> that
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declares a POSIX-compliant localtime_r, for the benefit of older
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implementations that lack localtime_r or have a nonstandard one.
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See the gnulib time_r module for one way to implement this. */
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# undef __localtime_r
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# define __localtime_r localtime_r
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# define __mktime_internal mktime_internal
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# include "mktime-internal.h"
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#endif
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/* Return 1 if the values A and B differ according to the rules for
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tm_isdst: A and B differ if one is zero and the other positive. */
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static int
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isdst_differ (int a, int b)
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{
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return (!a != !b) && (0 <= a) && (0 <= b);
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}
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/* Return an integer value measuring (YEAR1-YDAY1 HOUR1:MIN1:SEC1) -
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(YEAR0-YDAY0 HOUR0:MIN0:SEC0) in seconds, assuming that the clocks
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were not adjusted between the time stamps.
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The YEAR values uses the same numbering as TP->tm_year. Values
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need not be in the usual range. However, YEAR1 must not be less
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than 2 * INT_MIN or greater than 2 * INT_MAX.
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The result may overflow. It is the caller's responsibility to
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detect overflow. */
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static time_t
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ydhms_diff (long_int year1, long_int yday1, int hour1, int min1, int sec1,
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int year0, int yday0, int hour0, int min0, int sec0)
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{
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verify (C99_integer_division, -1 / 2 == 0);
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/* Compute intervening leap days correctly even if year is negative.
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Take care to avoid integer overflow here. */
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int a4 = SHR (year1, 2) + SHR (TM_YEAR_BASE, 2) - ! (year1 & 3);
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int b4 = SHR (year0, 2) + SHR (TM_YEAR_BASE, 2) - ! (year0 & 3);
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int a100 = a4 / 25 - (a4 % 25 < 0);
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int b100 = b4 / 25 - (b4 % 25 < 0);
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int a400 = SHR (a100, 2);
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int b400 = SHR (b100, 2);
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int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);
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/* Compute the desired time in time_t precision. Overflow might
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occur here. */
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time_t tyear1 = year1;
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time_t years = tyear1 - year0;
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time_t days = 365 * years + yday1 - yday0 + intervening_leap_days;
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time_t hours = 24 * days + hour1 - hour0;
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time_t minutes = 60 * hours + min1 - min0;
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time_t seconds = 60 * minutes + sec1 - sec0;
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return seconds;
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}
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/* Return the average of A and B, even if A + B would overflow. */
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static time_t
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time_t_avg (time_t a, time_t b)
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{
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return SHR (a, 1) + SHR (b, 1) + (a & b & 1);
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}
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/* Return 1 if A + B does not overflow. If time_t is unsigned and if
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B's top bit is set, assume that the sum represents A - -B, and
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return 1 if the subtraction does not wrap around. */
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static int
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time_t_add_ok (time_t a, time_t b)
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{
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if (! TYPE_SIGNED (time_t))
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{
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time_t sum = a + b;
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return (sum < a) == (TIME_T_MIDPOINT <= b);
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}
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else if (WRAPV)
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{
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time_t sum = a + b;
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return (sum < a) == (b < 0);
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}
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else
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{
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time_t avg = time_t_avg (a, b);
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return TIME_T_MIN / 2 <= avg && avg <= TIME_T_MAX / 2;
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}
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}
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/* Return 1 if A + B does not overflow. */
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static int
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time_t_int_add_ok (time_t a, int b)
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{
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verify (int_no_wider_than_time_t, INT_MAX <= TIME_T_MAX);
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if (WRAPV)
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{
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time_t sum = a + b;
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return (sum < a) == (b < 0);
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}
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else
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{
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int a_odd = a & 1;
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time_t avg = SHR (a, 1) + (SHR (b, 1) + (a_odd & b));
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return TIME_T_MIN / 2 <= avg && avg <= TIME_T_MAX / 2;
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}
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}
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/* Return a time_t value corresponding to (YEAR-YDAY HOUR:MIN:SEC),
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assuming that *T corresponds to *TP and that no clock adjustments
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occurred between *TP and the desired time.
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If TP is null, return a value not equal to *T; this avoids false matches.
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If overflow occurs, yield the minimal or maximal value, except do not
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yield a value equal to *T. */
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static time_t
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guess_time_tm (long_int year, long_int yday, int hour, int min, int sec,
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const time_t *t, const struct tm *tp)
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{
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if (tp)
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{
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time_t d = ydhms_diff (year, yday, hour, min, sec,
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tp->tm_year, tp->tm_yday,
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tp->tm_hour, tp->tm_min, tp->tm_sec);
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if (time_t_add_ok (*t, d))
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return *t + d;
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}
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/* Overflow occurred one way or another. Return the nearest result
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that is actually in range, except don't report a zero difference
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if the actual difference is nonzero, as that would cause a false
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match; and don't oscillate between two values, as that would
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confuse the spring-forward gap detector. */
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return (*t < TIME_T_MIDPOINT
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? (*t <= TIME_T_MIN + 1 ? *t + 1 : TIME_T_MIN)
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: (TIME_T_MAX - 1 <= *t ? *t - 1 : TIME_T_MAX));
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}
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/* Use CONVERT to convert *T to a broken down time in *TP.
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If *T is out of range for conversion, adjust it so that
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it is the nearest in-range value and then convert that. */
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static struct tm *
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ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
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time_t *t, struct tm *tp)
|
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{
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struct tm *r = convert (t, tp);
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if (!r && *t)
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{
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time_t bad = *t;
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time_t ok = 0;
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/* BAD is a known unconvertible time_t, and OK is a known good one.
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Use binary search to narrow the range between BAD and OK until
|
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they differ by 1. */
|
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while (bad != ok + (bad < 0 ? -1 : 1))
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{
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time_t mid = *t = time_t_avg (ok, bad);
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r = convert (t, tp);
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if (r)
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ok = mid;
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else
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bad = mid;
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}
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if (!r && ok)
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{
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/* The last conversion attempt failed;
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||
revert to the most recent successful attempt. */
|
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*t = ok;
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r = convert (t, tp);
|
||
}
|
||
}
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||
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||
return r;
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||
}
|
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|
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|
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/* Convert *TP to a time_t value, inverting
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the monotonic and mostly-unit-linear conversion function CONVERT.
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Use *OFFSET to keep track of a guess at the offset of the result,
|
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compared to what the result would be for UTC without leap seconds.
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If *OFFSET's guess is correct, only one CONVERT call is needed.
|
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This function is external because it is used also by timegm.c. */
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time_t
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__mktime_internal (struct tm *tp,
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struct tm *(*convert) (const time_t *, struct tm *),
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time_t *offset)
|
||
{
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||
time_t t, gt, t0, t1, t2;
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struct tm tm;
|
||
|
||
/* The maximum number of probes (calls to CONVERT) should be enough
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to handle any combinations of time zone rule changes, solar time,
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leap seconds, and oscillations around a spring-forward gap.
|
||
POSIX.1 prohibits leap seconds, but some hosts have them anyway. */
|
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int remaining_probes = 6;
|
||
|
||
/* Time requested. Copy it in case CONVERT modifies *TP; this can
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occur if TP is localtime's returned value and CONVERT is localtime. */
|
||
int sec = tp->tm_sec;
|
||
int min = tp->tm_min;
|
||
int hour = tp->tm_hour;
|
||
int mday = tp->tm_mday;
|
||
int mon = tp->tm_mon;
|
||
int year_requested = tp->tm_year;
|
||
int isdst = tp->tm_isdst;
|
||
|
||
/* 1 if the previous probe was DST. */
|
||
int dst2;
|
||
|
||
/* Ensure that mon is in range, and set year accordingly. */
|
||
int mon_remainder = mon % 12;
|
||
int negative_mon_remainder = mon_remainder < 0;
|
||
int mon_years = mon / 12 - negative_mon_remainder;
|
||
long_int lyear_requested = year_requested;
|
||
long_int year = lyear_requested + mon_years;
|
||
|
||
/* The other values need not be in range:
|
||
the remaining code handles minor overflows correctly,
|
||
assuming int and time_t arithmetic wraps around.
|
||
Major overflows are caught at the end. */
|
||
|
||
/* Calculate day of year from year, month, and day of month.
|
||
The result need not be in range. */
|
||
int mon_yday = ((__mon_yday[leapyear (year)]
|
||
[mon_remainder + 12 * negative_mon_remainder])
|
||
- 1);
|
||
long_int lmday = mday;
|
||
long_int yday = mon_yday + lmday;
|
||
|
||
time_t guessed_offset = *offset;
|
||
|
||
int sec_requested = sec;
|
||
|
||
if (LEAP_SECONDS_POSSIBLE)
|
||
{
|
||
/* Handle out-of-range seconds specially,
|
||
since ydhms_tm_diff assumes every minute has 60 seconds. */
|
||
if (sec < 0)
|
||
sec = 0;
|
||
if (59 < sec)
|
||
sec = 59;
|
||
}
|
||
|
||
/* Invert CONVERT by probing. First assume the same offset as last
|
||
time. */
|
||
|
||
t0 = ydhms_diff (year, yday, hour, min, sec,
|
||
EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, - guessed_offset);
|
||
|
||
if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3)
|
||
{
|
||
/* time_t isn't large enough to rule out overflows, so check
|
||
for major overflows. A gross check suffices, since if t0
|
||
has overflowed, it is off by a multiple of TIME_T_MAX -
|
||
TIME_T_MIN + 1. So ignore any component of the difference
|
||
that is bounded by a small value. */
|
||
|
||
/* Approximate log base 2 of the number of time units per
|
||
biennium. A biennium is 2 years; use this unit instead of
|
||
years to avoid integer overflow. For example, 2 average
|
||
Gregorian years are 2 * 365.2425 * 24 * 60 * 60 seconds,
|
||
which is 63113904 seconds, and rint (log2 (63113904)) is
|
||
26. */
|
||
int ALOG2_SECONDS_PER_BIENNIUM = 26;
|
||
int ALOG2_MINUTES_PER_BIENNIUM = 20;
|
||
int ALOG2_HOURS_PER_BIENNIUM = 14;
|
||
int ALOG2_DAYS_PER_BIENNIUM = 10;
|
||
int LOG2_YEARS_PER_BIENNIUM = 1;
|
||
|
||
int approx_requested_biennia =
|
||
(SHR (year_requested, LOG2_YEARS_PER_BIENNIUM)
|
||
- SHR (EPOCH_YEAR - TM_YEAR_BASE, LOG2_YEARS_PER_BIENNIUM)
|
||
+ SHR (mday, ALOG2_DAYS_PER_BIENNIUM)
|
||
+ SHR (hour, ALOG2_HOURS_PER_BIENNIUM)
|
||
+ SHR (min, ALOG2_MINUTES_PER_BIENNIUM)
|
||
+ (LEAP_SECONDS_POSSIBLE
|
||
? 0
|
||
: SHR (sec, ALOG2_SECONDS_PER_BIENNIUM)));
|
||
|
||
int approx_biennia = SHR (t0, ALOG2_SECONDS_PER_BIENNIUM);
|
||
int diff = approx_biennia - approx_requested_biennia;
|
||
int approx_abs_diff = diff < 0 ? -1 - diff : diff;
|
||
|
||
/* IRIX 4.0.5 cc miscalculates TIME_T_MIN / 3: it erroneously
|
||
gives a positive value of 715827882. Setting a variable
|
||
first then doing math on it seems to work.
|
||
(ghazi@caip.rutgers.edu) */
|
||
time_t time_t_max = TIME_T_MAX;
|
||
time_t time_t_min = TIME_T_MIN;
|
||
time_t overflow_threshold =
|
||
(time_t_max / 3 - time_t_min / 3) >> ALOG2_SECONDS_PER_BIENNIUM;
|
||
|
||
if (overflow_threshold < approx_abs_diff)
|
||
{
|
||
/* Overflow occurred. Try repairing it; this might work if
|
||
the time zone offset is enough to undo the overflow. */
|
||
time_t repaired_t0 = -1 - t0;
|
||
approx_biennia = SHR (repaired_t0, ALOG2_SECONDS_PER_BIENNIUM);
|
||
diff = approx_biennia - approx_requested_biennia;
|
||
approx_abs_diff = diff < 0 ? -1 - diff : diff;
|
||
if (overflow_threshold < approx_abs_diff)
|
||
return -1;
|
||
guessed_offset += repaired_t0 - t0;
|
||
t0 = repaired_t0;
|
||
}
|
||
}
|
||
|
||
/* Repeatedly use the error to improve the guess. */
|
||
|
||
for (t = t1 = t2 = t0, dst2 = 0;
|
||
(gt = guess_time_tm (year, yday, hour, min, sec, &t,
|
||
ranged_convert (convert, &t, &tm)),
|
||
t != gt);
|
||
t1 = t2, t2 = t, t = gt, dst2 = tm.tm_isdst != 0)
|
||
if (t == t1 && t != t2
|
||
&& (tm.tm_isdst < 0
|
||
|| (isdst < 0
|
||
? dst2 <= (tm.tm_isdst != 0)
|
||
: (isdst != 0) != (tm.tm_isdst != 0))))
|
||
/* We can't possibly find a match, as we are oscillating
|
||
between two values. The requested time probably falls
|
||
within a spring-forward gap of size GT - T. Follow the common
|
||
practice in this case, which is to return a time that is GT - T
|
||
away from the requested time, preferring a time whose
|
||
tm_isdst differs from the requested value. (If no tm_isdst
|
||
was requested and only one of the two values has a nonzero
|
||
tm_isdst, prefer that value.) In practice, this is more
|
||
useful than returning -1. */
|
||
goto offset_found;
|
||
else if (--remaining_probes == 0)
|
||
return -1;
|
||
|
||
/* We have a match. Check whether tm.tm_isdst has the requested
|
||
value, if any. */
|
||
if (isdst_differ (isdst, tm.tm_isdst))
|
||
{
|
||
/* tm.tm_isdst has the wrong value. Look for a neighboring
|
||
time with the right value, and use its UTC offset.
|
||
|
||
Heuristic: probe the adjacent timestamps in both directions,
|
||
looking for the desired isdst. This should work for all real
|
||
time zone histories in the tz database. */
|
||
|
||
/* Distance between probes when looking for a DST boundary. In
|
||
tzdata2003a, the shortest period of DST is 601200 seconds
|
||
(e.g., America/Recife starting 2000-10-08 01:00), and the
|
||
shortest period of non-DST surrounded by DST is 694800
|
||
seconds (Africa/Tunis starting 1943-04-17 01:00). Use the
|
||
minimum of these two values, so we don't miss these short
|
||
periods when probing. */
|
||
int stride = 601200;
|
||
|
||
/* The longest period of DST in tzdata2003a is 536454000 seconds
|
||
(e.g., America/Jujuy starting 1946-10-01 01:00). The longest
|
||
period of non-DST is much longer, but it makes no real sense
|
||
to search for more than a year of non-DST, so use the DST
|
||
max. */
|
||
int duration_max = 536454000;
|
||
|
||
/* Search in both directions, so the maximum distance is half
|
||
the duration; add the stride to avoid off-by-1 problems. */
|
||
int delta_bound = duration_max / 2 + stride;
|
||
|
||
int delta, direction;
|
||
|
||
for (delta = stride; delta < delta_bound; delta += stride)
|
||
for (direction = -1; direction <= 1; direction += 2)
|
||
if (time_t_int_add_ok (t, delta * direction))
|
||
{
|
||
time_t ot = t + delta * direction;
|
||
struct tm otm;
|
||
ranged_convert (convert, &ot, &otm);
|
||
if (! isdst_differ (isdst, otm.tm_isdst))
|
||
{
|
||
/* We found the desired tm_isdst.
|
||
Extrapolate back to the desired time. */
|
||
t = guess_time_tm (year, yday, hour, min, sec, &ot, &otm);
|
||
ranged_convert (convert, &t, &tm);
|
||
goto offset_found;
|
||
}
|
||
}
|
||
}
|
||
|
||
offset_found:
|
||
*offset = guessed_offset + t - t0;
|
||
|
||
if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec)
|
||
{
|
||
/* Adjust time to reflect the tm_sec requested, not the normalized value.
|
||
Also, repair any damage from a false match due to a leap second. */
|
||
int sec_adjustment = (sec == 0 && tm.tm_sec == 60) - sec;
|
||
if (! time_t_int_add_ok (t, sec_requested))
|
||
return -1;
|
||
t1 = t + sec_requested;
|
||
if (! time_t_int_add_ok (t1, sec_adjustment))
|
||
return -1;
|
||
t2 = t1 + sec_adjustment;
|
||
if (! convert (&t2, &tm))
|
||
return -1;
|
||
t = t2;
|
||
}
|
||
|
||
*tp = tm;
|
||
return t;
|
||
}
|
||
|
||
|
||
/* FIXME: This should use a signed type wide enough to hold any UTC
|
||
offset in seconds. 'int' should be good enough for GNU code. We
|
||
can't fix this unilaterally though, as other modules invoke
|
||
__mktime_internal. */
|
||
static time_t localtime_offset;
|
||
|
||
/* Convert *TP to a time_t value. */
|
||
time_t
|
||
mktime (struct tm *tp)
|
||
{
|
||
#ifdef _LIBC
|
||
/* POSIX.1 8.1.1 requires that whenever mktime() is called, the
|
||
time zone names contained in the external variable 'tzname' shall
|
||
be set as if the tzset() function had been called. */
|
||
__tzset ();
|
||
#endif
|
||
|
||
return __mktime_internal (tp, __localtime_r, &localtime_offset);
|
||
}
|
||
|
||
#ifdef weak_alias
|
||
weak_alias (mktime, timelocal)
|
||
#endif
|
||
|
||
#ifdef _LIBC
|
||
libc_hidden_def (mktime)
|
||
libc_hidden_weak (timelocal)
|
||
#endif
|
||
|
||
#if defined DEBUG && DEBUG
|
||
|
||
static int
|
||
not_equal_tm (const struct tm *a, const struct tm *b)
|
||
{
|
||
return ((a->tm_sec ^ b->tm_sec)
|
||
| (a->tm_min ^ b->tm_min)
|
||
| (a->tm_hour ^ b->tm_hour)
|
||
| (a->tm_mday ^ b->tm_mday)
|
||
| (a->tm_mon ^ b->tm_mon)
|
||
| (a->tm_year ^ b->tm_year)
|
||
| (a->tm_yday ^ b->tm_yday)
|
||
| isdst_differ (a->tm_isdst, b->tm_isdst));
|
||
}
|
||
|
||
static void
|
||
print_tm (const struct tm *tp)
|
||
{
|
||
if (tp)
|
||
printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
|
||
tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
|
||
tp->tm_hour, tp->tm_min, tp->tm_sec,
|
||
tp->tm_yday, tp->tm_wday, tp->tm_isdst);
|
||
else
|
||
printf ("0");
|
||
}
|
||
|
||
static int
|
||
check_result (time_t tk, struct tm tmk, time_t tl, const struct tm *lt)
|
||
{
|
||
if (tk != tl || !lt || not_equal_tm (&tmk, lt))
|
||
{
|
||
printf ("mktime (");
|
||
print_tm (lt);
|
||
printf (")\nyields (");
|
||
print_tm (&tmk);
|
||
printf (") == %ld, should be %ld\n", (long int) tk, (long int) tl);
|
||
return 1;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
int
|
||
main (int argc, char **argv)
|
||
{
|
||
int status = 0;
|
||
struct tm tm, tmk, tml;
|
||
struct tm *lt;
|
||
time_t tk, tl, tl1;
|
||
char trailer;
|
||
|
||
if ((argc == 3 || argc == 4)
|
||
&& (sscanf (argv[1], "%d-%d-%d%c",
|
||
&tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer)
|
||
== 3)
|
||
&& (sscanf (argv[2], "%d:%d:%d%c",
|
||
&tm.tm_hour, &tm.tm_min, &tm.tm_sec, &trailer)
|
||
== 3))
|
||
{
|
||
tm.tm_year -= TM_YEAR_BASE;
|
||
tm.tm_mon--;
|
||
tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]);
|
||
tmk = tm;
|
||
tl = mktime (&tmk);
|
||
lt = localtime (&tl);
|
||
if (lt)
|
||
{
|
||
tml = *lt;
|
||
lt = &tml;
|
||
}
|
||
printf ("mktime returns %ld == ", (long int) tl);
|
||
print_tm (&tmk);
|
||
printf ("\n");
|
||
status = check_result (tl, tmk, tl, lt);
|
||
}
|
||
else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0))
|
||
{
|
||
time_t from = atol (argv[1]);
|
||
time_t by = atol (argv[2]);
|
||
time_t to = atol (argv[3]);
|
||
|
||
if (argc == 4)
|
||
for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
|
||
{
|
||
lt = localtime (&tl);
|
||
if (lt)
|
||
{
|
||
tmk = tml = *lt;
|
||
tk = mktime (&tmk);
|
||
status |= check_result (tk, tmk, tl, &tml);
|
||
}
|
||
else
|
||
{
|
||
printf ("localtime (%ld) yields 0\n", (long int) tl);
|
||
status = 1;
|
||
}
|
||
tl1 = tl + by;
|
||
if ((tl1 < tl) != (by < 0))
|
||
break;
|
||
}
|
||
else
|
||
for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
|
||
{
|
||
/* Null benchmark. */
|
||
lt = localtime (&tl);
|
||
if (lt)
|
||
{
|
||
tmk = tml = *lt;
|
||
tk = tl;
|
||
status |= check_result (tk, tmk, tl, &tml);
|
||
}
|
||
else
|
||
{
|
||
printf ("localtime (%ld) yields 0\n", (long int) tl);
|
||
status = 1;
|
||
}
|
||
tl1 = tl + by;
|
||
if ((tl1 < tl) != (by < 0))
|
||
break;
|
||
}
|
||
}
|
||
else
|
||
printf ("Usage:\
|
||
\t%s YYYY-MM-DD HH:MM:SS [ISDST] # Test given time.\n\
|
||
\t%s FROM BY TO # Test values FROM, FROM+BY, ..., TO.\n\
|
||
\t%s FROM BY TO - # Do not test those values (for benchmark).\n",
|
||
argv[0], argv[0], argv[0]);
|
||
|
||
return status;
|
||
}
|
||
|
||
#endif /* DEBUG */
|
||
|
||
/*
|
||
Local Variables:
|
||
compile-command: "gcc -DDEBUG -I. -Wall -W -O2 -g mktime.c -o mktime"
|
||
End:
|
||
*/
|