815.1.1
by Monty Taylor
Add timegm which is missing on Solaris. |
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/* Convert a `struct tm' to a time_t value.
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Copyright (C) 1993-1999, 2002-2005, 2006, 2007 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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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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This program 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
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License along
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with this program; if not, write to the Free Software Foundation,
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Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
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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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994.2.8
by Monty Taylor
Updated gnulib files. |
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#if DEBUG
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815.1.1
by Monty Taylor
Add timegm which is missing on Solaris. |
42 |
# 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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# define mktime my_mktime
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#endif /* DEBUG */ |
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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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? (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, ones' complement, or signed magnitude representation,
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respectively. Much GNU code assumes two's complement, but some
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people like to be portable to all possible C hosts. */
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#define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
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#define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
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#define TYPE_SIGNED_MAGNITUDE(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_SIGNED_MAGNITUDE (t) \
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? ~ (t) 0 \
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: ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
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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) 0 << (sizeof (t) * CHAR_BIT - 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 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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verify (time_t_is_integer, TYPE_IS_INTEGER (time_t)); |
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verify (twos_complement_arithmetic, TYPE_TWOS_COMPLEMENT (int)); |
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/* The code also assumes that signed integer overflow silently wraps
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around, but this assumption can't be stated without causing a
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diagnostic on some hosts. */
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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 inline 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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#endif
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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 inline 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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verify (long_int_year_and_yday_are_wide_enough, |
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INT_MAX <= LONG_MAX / 2 || TIME_T_MAX <= UINT_MAX); |
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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 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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time_t t1 = *t + d; |
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if ((t1 < *t) == (TYPE_SIGNED (time_t) ? d < 0 : TIME_T_MAX / 2 < d)) |
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return t1; |
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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 = (bad < 0 |
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? bad + ((ok - bad) >> 1) |
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: ok + ((bad - ok) >> 1)); |
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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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}
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return r; |
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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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{
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time_t t, gt, t0, t1, t2; |
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struct tm tm; |
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279 |
/* 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.
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POSIX.1 prohibits leap seconds, but some hosts have them anyway. */
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int remaining_probes = 6; |
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/* 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. */
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int sec = tp->tm_sec; |
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int min = tp->tm_min; |
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int hour = tp->tm_hour; |
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int mday = tp->tm_mday; |
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int mon = tp->tm_mon; |
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int year_requested = tp->tm_year; |
|
994.2.8
by Monty Taylor
Updated gnulib files. |
293 |
/* Normalize the value. */
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294 |
int isdst = ((tp->tm_isdst >> (8 * sizeof (tp->tm_isdst) - 1)) |
|
295 |
| (tp->tm_isdst != 0)); |
|
815.1.1
by Monty Taylor
Add timegm which is missing on Solaris. |
296 |
|
297 |
/* 1 if the previous probe was DST. */
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298 |
int dst2; |
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299 |
||
300 |
/* Ensure that mon is in range, and set year accordingly. */
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int mon_remainder = mon % 12; |
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302 |
int negative_mon_remainder = mon_remainder < 0; |
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303 |
int mon_years = mon / 12 - negative_mon_remainder; |
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304 |
long int lyear_requested = year_requested; |
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305 |
long int year = lyear_requested + mon_years; |
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306 |
||
307 |
/* The other values need not be in range:
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308 |
the remaining code handles minor overflows correctly,
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309 |
assuming int and time_t arithmetic wraps around.
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310 |
Major overflows are caught at the end. */
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311 |
||
312 |
/* Calculate day of year from year, month, and day of month.
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313 |
The result need not be in range. */
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314 |
int mon_yday = ((__mon_yday[leapyear (year)] |
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315 |
[mon_remainder + 12 * negative_mon_remainder]) |
|
316 |
- 1); |
|
317 |
long int lmday = mday; |
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318 |
long int yday = mon_yday + lmday; |
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319 |
||
320 |
time_t guessed_offset = *offset; |
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321 |
||
322 |
int sec_requested = sec; |
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323 |
||
324 |
if (LEAP_SECONDS_POSSIBLE) |
|
325 |
{
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326 |
/* Handle out-of-range seconds specially,
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327 |
since ydhms_tm_diff assumes every minute has 60 seconds. */
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328 |
if (sec < 0) |
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329 |
sec = 0; |
|
330 |
if (59 < sec) |
|
331 |
sec = 59; |
|
332 |
}
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333 |
||
334 |
/* Invert CONVERT by probing. First assume the same offset as last
|
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335 |
time. */
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336 |
||
337 |
t0 = ydhms_diff (year, yday, hour, min, sec, |
|
338 |
EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, - guessed_offset); |
|
339 |
||
340 |
if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3) |
|
341 |
{
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342 |
/* time_t isn't large enough to rule out overflows, so check
|
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343 |
for major overflows. A gross check suffices, since if t0
|
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344 |
has overflowed, it is off by a multiple of TIME_T_MAX -
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345 |
TIME_T_MIN + 1. So ignore any component of the difference
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346 |
that is bounded by a small value. */
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347 |
||
348 |
/* Approximate log base 2 of the number of time units per
|
|
349 |
biennium. A biennium is 2 years; use this unit instead of
|
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350 |
years to avoid integer overflow. For example, 2 average
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|
351 |
Gregorian years are 2 * 365.2425 * 24 * 60 * 60 seconds,
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352 |
which is 63113904 seconds, and rint (log2 (63113904)) is
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353 |
26. */
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354 |
int ALOG2_SECONDS_PER_BIENNIUM = 26; |
|
355 |
int ALOG2_MINUTES_PER_BIENNIUM = 20; |
|
356 |
int ALOG2_HOURS_PER_BIENNIUM = 14; |
|
357 |
int ALOG2_DAYS_PER_BIENNIUM = 10; |
|
358 |
int LOG2_YEARS_PER_BIENNIUM = 1; |
|
359 |
||
360 |
int approx_requested_biennia = |
|
361 |
(SHR (year_requested, LOG2_YEARS_PER_BIENNIUM) |
|
362 |
- SHR (EPOCH_YEAR - TM_YEAR_BASE, LOG2_YEARS_PER_BIENNIUM) |
|
363 |
+ SHR (mday, ALOG2_DAYS_PER_BIENNIUM) |
|
364 |
+ SHR (hour, ALOG2_HOURS_PER_BIENNIUM) |
|
365 |
+ SHR (min, ALOG2_MINUTES_PER_BIENNIUM) |
|
366 |
+ (LEAP_SECONDS_POSSIBLE |
|
367 |
? 0 |
|
368 |
: SHR (sec, ALOG2_SECONDS_PER_BIENNIUM))); |
|
369 |
||
370 |
int approx_biennia = SHR (t0, ALOG2_SECONDS_PER_BIENNIUM); |
|
371 |
int diff = approx_biennia - approx_requested_biennia; |
|
372 |
int abs_diff = diff < 0 ? - diff : diff; |
|
373 |
||
374 |
/* IRIX 4.0.5 cc miscaculates TIME_T_MIN / 3: it erroneously
|
|
375 |
gives a positive value of 715827882. Setting a variable
|
|
376 |
first then doing math on it seems to work.
|
|
377 |
(ghazi@caip.rutgers.edu) */
|
|
378 |
time_t time_t_max = TIME_T_MAX; |
|
379 |
time_t time_t_min = TIME_T_MIN; |
|
380 |
time_t overflow_threshold = |
|
381 |
(time_t_max / 3 - time_t_min / 3) >> ALOG2_SECONDS_PER_BIENNIUM; |
|
382 |
||
383 |
if (overflow_threshold < abs_diff) |
|
384 |
{
|
|
385 |
/* Overflow occurred. Try repairing it; this might work if
|
|
386 |
the time zone offset is enough to undo the overflow. */
|
|
387 |
time_t repaired_t0 = -1 - t0; |
|
388 |
approx_biennia = SHR (repaired_t0, ALOG2_SECONDS_PER_BIENNIUM); |
|
389 |
diff = approx_biennia - approx_requested_biennia; |
|
390 |
abs_diff = diff < 0 ? - diff : diff; |
|
391 |
if (overflow_threshold < abs_diff) |
|
392 |
return -1; |
|
393 |
guessed_offset += repaired_t0 - t0; |
|
394 |
t0 = repaired_t0; |
|
395 |
}
|
|
396 |
}
|
|
397 |
||
398 |
/* Repeatedly use the error to improve the guess. */
|
|
399 |
||
400 |
for (t = t1 = t2 = t0, dst2 = 0; |
|
401 |
(gt = guess_time_tm (year, yday, hour, min, sec, &t, |
|
402 |
ranged_convert (convert, &t, &tm)), |
|
403 |
t != gt); |
|
404 |
t1 = t2, t2 = t, t = gt, dst2 = tm.tm_isdst != 0) |
|
405 |
if (t == t1 && t != t2 |
|
406 |
&& (tm.tm_isdst < 0 |
|
407 |
|| (isdst < 0 |
|
408 |
? dst2 <= (tm.tm_isdst != 0) |
|
409 |
: (isdst != 0) != (tm.tm_isdst != 0)))) |
|
410 |
/* We can't possibly find a match, as we are oscillating
|
|
411 |
between two values. The requested time probably falls
|
|
412 |
within a spring-forward gap of size GT - T. Follow the common
|
|
413 |
practice in this case, which is to return a time that is GT - T
|
|
414 |
away from the requested time, preferring a time whose
|
|
415 |
tm_isdst differs from the requested value. (If no tm_isdst
|
|
416 |
was requested and only one of the two values has a nonzero
|
|
417 |
tm_isdst, prefer that value.) In practice, this is more
|
|
418 |
useful than returning -1. */
|
|
419 |
goto offset_found; |
|
420 |
else if (--remaining_probes == 0) |
|
421 |
return -1; |
|
422 |
||
423 |
/* We have a match. Check whether tm.tm_isdst has the requested
|
|
424 |
value, if any. */
|
|
425 |
if (isdst != tm.tm_isdst && 0 <= isdst && 0 <= tm.tm_isdst) |
|
426 |
{
|
|
427 |
/* tm.tm_isdst has the wrong value. Look for a neighboring
|
|
428 |
time with the right value, and use its UTC offset.
|
|
429 |
||
430 |
Heuristic: probe the adjacent timestamps in both directions,
|
|
431 |
looking for the desired isdst. This should work for all real
|
|
432 |
time zone histories in the tz database. */
|
|
433 |
||
434 |
/* Distance between probes when looking for a DST boundary. In
|
|
435 |
tzdata2003a, the shortest period of DST is 601200 seconds
|
|
436 |
(e.g., America/Recife starting 2000-10-08 01:00), and the
|
|
437 |
shortest period of non-DST surrounded by DST is 694800
|
|
438 |
seconds (Africa/Tunis starting 1943-04-17 01:00). Use the
|
|
439 |
minimum of these two values, so we don't miss these short
|
|
440 |
periods when probing. */
|
|
441 |
int stride = 601200; |
|
442 |
||
443 |
/* The longest period of DST in tzdata2003a is 536454000 seconds
|
|
444 |
(e.g., America/Jujuy starting 1946-10-01 01:00). The longest
|
|
445 |
period of non-DST is much longer, but it makes no real sense
|
|
446 |
to search for more than a year of non-DST, so use the DST
|
|
447 |
max. */
|
|
448 |
int duration_max = 536454000; |
|
449 |
||
450 |
/* Search in both directions, so the maximum distance is half
|
|
451 |
the duration; add the stride to avoid off-by-1 problems. */
|
|
452 |
int delta_bound = duration_max / 2 + stride; |
|
453 |
||
454 |
int delta, direction; |
|
455 |
||
456 |
for (delta = stride; delta < delta_bound; delta += stride) |
|
457 |
for (direction = -1; direction <= 1; direction += 2) |
|
458 |
{
|
|
459 |
time_t ot = t + delta * direction; |
|
460 |
if ((ot < t) == (direction < 0)) |
|
461 |
{
|
|
462 |
struct tm otm; |
|
463 |
ranged_convert (convert, &ot, &otm); |
|
464 |
if (otm.tm_isdst == isdst) |
|
465 |
{
|
|
466 |
/* We found the desired tm_isdst.
|
|
467 |
Extrapolate back to the desired time. */
|
|
468 |
t = guess_time_tm (year, yday, hour, min, sec, &ot, &otm); |
|
469 |
ranged_convert (convert, &t, &tm); |
|
470 |
goto offset_found; |
|
471 |
}
|
|
472 |
}
|
|
473 |
}
|
|
474 |
}
|
|
475 |
||
476 |
offset_found: |
|
477 |
*offset = guessed_offset + t - t0; |
|
478 |
||
479 |
if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec) |
|
480 |
{
|
|
481 |
/* Adjust time to reflect the tm_sec requested, not the normalized value.
|
|
482 |
Also, repair any damage from a false match due to a leap second. */
|
|
483 |
int sec_adjustment = (sec == 0 && tm.tm_sec == 60) - sec; |
|
484 |
t1 = t + sec_requested; |
|
485 |
t2 = t1 + sec_adjustment; |
|
486 |
if (((t1 < t) != (sec_requested < 0)) |
|
487 |
| ((t2 < t1) != (sec_adjustment < 0)) |
|
488 |
| ! convert (&t2, &tm)) |
|
489 |
return -1; |
|
490 |
t = t2; |
|
491 |
}
|
|
492 |
||
493 |
*tp = tm; |
|
494 |
return t; |
|
495 |
}
|
|
496 |
||
497 |
||
498 |
/* FIXME: This should use a signed type wide enough to hold any UTC
|
|
499 |
offset in seconds. 'int' should be good enough for GNU code. We
|
|
500 |
can't fix this unilaterally though, as other modules invoke
|
|
501 |
__mktime_internal. */
|
|
502 |
static time_t localtime_offset; |
|
503 |
||
504 |
/* Convert *TP to a time_t value. */
|
|
505 |
time_t
|
|
506 |
mktime (struct tm *tp) |
|
507 |
{
|
|
508 |
#ifdef _LIBC
|
|
509 |
/* POSIX.1 8.1.1 requires that whenever mktime() is called, the
|
|
510 |
time zone names contained in the external variable `tzname' shall
|
|
511 |
be set as if the tzset() function had been called. */
|
|
512 |
__tzset (); |
|
513 |
#endif
|
|
514 |
||
515 |
return __mktime_internal (tp, __localtime_r, &localtime_offset); |
|
516 |
}
|
|
517 |
||
518 |
#ifdef weak_alias
|
|
519 |
weak_alias (mktime, timelocal) |
|
520 |
#endif
|
|
521 |
||
522 |
#ifdef _LIBC
|
|
523 |
libc_hidden_def (mktime) |
|
524 |
libc_hidden_weak (timelocal) |
|
525 |
#endif
|
|
526 |
||
994.2.8
by Monty Taylor
Updated gnulib files. |
527 |
#if DEBUG
|
815.1.1
by Monty Taylor
Add timegm which is missing on Solaris. |
528 |
|
529 |
static int |
|
530 |
not_equal_tm (const struct tm *a, const struct tm *b) |
|
531 |
{
|
|
532 |
return ((a->tm_sec ^ b->tm_sec) |
|
533 |
| (a->tm_min ^ b->tm_min) |
|
534 |
| (a->tm_hour ^ b->tm_hour) |
|
535 |
| (a->tm_mday ^ b->tm_mday) |
|
536 |
| (a->tm_mon ^ b->tm_mon) |
|
537 |
| (a->tm_year ^ b->tm_year) |
|
538 |
| (a->tm_yday ^ b->tm_yday) |
|
539 |
| (a->tm_isdst ^ b->tm_isdst)); |
|
540 |
}
|
|
541 |
||
542 |
static void |
|
543 |
print_tm (const struct tm *tp) |
|
544 |
{
|
|
545 |
if (tp) |
|
546 |
printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d", |
|
547 |
tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday, |
|
548 |
tp->tm_hour, tp->tm_min, tp->tm_sec, |
|
549 |
tp->tm_yday, tp->tm_wday, tp->tm_isdst); |
|
550 |
else
|
|
551 |
printf ("0"); |
|
552 |
}
|
|
553 |
||
554 |
static int |
|
555 |
check_result (time_t tk, struct tm tmk, time_t tl, const struct tm *lt) |
|
556 |
{
|
|
557 |
if (tk != tl || !lt || not_equal_tm (&tmk, lt)) |
|
558 |
{
|
|
559 |
printf ("mktime ("); |
|
560 |
print_tm (lt); |
|
561 |
printf (")\nyields ("); |
|
562 |
print_tm (&tmk); |
|
563 |
printf (") == %ld, should be %ld\n", (long int) tk, (long int) tl); |
|
564 |
return 1; |
|
565 |
}
|
|
566 |
||
567 |
return 0; |
|
568 |
}
|
|
569 |
||
570 |
int
|
|
571 |
main (int argc, char **argv) |
|
572 |
{
|
|
573 |
int status = 0; |
|
574 |
struct tm tm, tmk, tml; |
|
575 |
struct tm *lt; |
|
576 |
time_t tk, tl, tl1; |
|
577 |
char trailer; |
|
578 |
||
579 |
if ((argc == 3 || argc == 4) |
|
580 |
&& (sscanf (argv[1], "%d-%d-%d%c", |
|
581 |
&tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer) |
|
582 |
== 3) |
|
583 |
&& (sscanf (argv[2], "%d:%d:%d%c", |
|
584 |
&tm.tm_hour, &tm.tm_min, &tm.tm_sec, &trailer) |
|
585 |
== 3)) |
|
586 |
{
|
|
587 |
tm.tm_year -= TM_YEAR_BASE; |
|
588 |
tm.tm_mon--; |
|
589 |
tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]); |
|
590 |
tmk = tm; |
|
591 |
tl = mktime (&tmk); |
|
592 |
lt = localtime (&tl); |
|
593 |
if (lt) |
|
594 |
{
|
|
595 |
tml = *lt; |
|
596 |
lt = &tml; |
|
597 |
}
|
|
598 |
printf ("mktime returns %ld == ", (long int) tl); |
|
599 |
print_tm (&tmk); |
|
600 |
printf ("\n"); |
|
601 |
status = check_result (tl, tmk, tl, lt); |
|
602 |
}
|
|
603 |
else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0)) |
|
604 |
{
|
|
605 |
time_t from = atol (argv[1]); |
|
606 |
time_t by = atol (argv[2]); |
|
607 |
time_t to = atol (argv[3]); |
|
608 |
||
609 |
if (argc == 4) |
|
610 |
for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1) |
|
611 |
{
|
|
612 |
lt = localtime (&tl); |
|
613 |
if (lt) |
|
614 |
{
|
|
615 |
tmk = tml = *lt; |
|
616 |
tk = mktime (&tmk); |
|
617 |
status |= check_result (tk, tmk, tl, &tml); |
|
618 |
}
|
|
619 |
else
|
|
620 |
{
|
|
621 |
printf ("localtime (%ld) yields 0\n", (long int) tl); |
|
622 |
status = 1; |
|
623 |
}
|
|
624 |
tl1 = tl + by; |
|
625 |
if ((tl1 < tl) != (by < 0)) |
|
626 |
break; |
|
627 |
}
|
|
628 |
else
|
|
629 |
for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1) |
|
630 |
{
|
|
631 |
/* Null benchmark. */
|
|
632 |
lt = localtime (&tl); |
|
633 |
if (lt) |
|
634 |
{
|
|
635 |
tmk = tml = *lt; |
|
636 |
tk = tl; |
|
637 |
status |= check_result (tk, tmk, tl, &tml); |
|
638 |
}
|
|
639 |
else
|
|
640 |
{
|
|
641 |
printf ("localtime (%ld) yields 0\n", (long int) tl); |
|
642 |
status = 1; |
|
643 |
}
|
|
644 |
tl1 = tl + by; |
|
645 |
if ((tl1 < tl) != (by < 0)) |
|
646 |
break; |
|
647 |
}
|
|
648 |
}
|
|
649 |
else
|
|
650 |
printf ("Usage:\ |
|
651 |
\t%s YYYY-MM-DD HH:MM:SS [ISDST] # Test given time.\n\ |
|
652 |
\t%s FROM BY TO # Test values FROM, FROM+BY, ..., TO.\n\ |
|
653 |
\t%s FROM BY TO - # Do not test those values (for benchmark).\n", |
|
654 |
argv[0], argv[0], argv[0]); |
|
655 |
||
656 |
return status; |
|
657 |
}
|
|
658 |
||
659 |
#endif /* DEBUG */ |
|
660 |
||
661 |
/*
|
|
662 |
Local Variables:
|
|
663 |
compile-command: "gcc -DDEBUG -Wall -W -O -g mktime.c -o mktime"
|
|
664 |
End:
|
|
665 |
*/
|