1 | /* Convert a `struct tm' to a time_t value.
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2 | Copyright (C) 1993-1999, 2002-2005, 2006 Free Software Foundation, Inc.
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3 | This file is part of the GNU C Library.
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4 | Contributed by Paul Eggert <eggert@twinsun.com>.
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5 |
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6 | This program is free software; you can redistribute it and/or modify
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7 | it under the terms of the GNU General Public License as published by
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8 | the Free Software Foundation; either version 2, or (at your option)
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9 | any later version.
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10 |
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11 | This program is distributed in the hope that it will be useful,
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12 | but WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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14 | GNU General Public License for more details.
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15 |
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16 | You should have received a copy of the GNU General Public License along
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17 | with this program; if not, write to the Free Software Foundation,
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18 | Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
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19 |
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20 | /* Define this to have a standalone program to test this implementation of
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21 | mktime. */
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22 | /* #define DEBUG 1 */
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23 |
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24 | #ifdef HAVE_CONFIG_H
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25 | # include <config.h>
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26 | #endif
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27 |
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28 | /* Assume that leap seconds are possible, unless told otherwise.
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29 | If the host has a `zic' command with a `-L leapsecondfilename' option,
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30 | then it supports leap seconds; otherwise it probably doesn't. */
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31 | #ifndef LEAP_SECONDS_POSSIBLE
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32 | # define LEAP_SECONDS_POSSIBLE 1
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33 | #endif
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34 |
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35 | #include <sys/types.h> /* Some systems define `time_t' here. */
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36 | #include <time.h>
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37 |
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38 | #include <limits.h>
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39 |
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40 | #include <string.h> /* For the real memcpy prototype. */
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41 |
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42 | #if DEBUG
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43 | # include <stdio.h>
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44 | # include <stdlib.h>
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45 | /* Make it work even if the system's libc has its own mktime routine. */
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46 | # define mktime my_mktime
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47 | #endif /* DEBUG */
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48 |
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49 | /* Shift A right by B bits portably, by dividing A by 2**B and
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50 | truncating towards minus infinity. A and B should be free of side
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51 | effects, and B should be in the range 0 <= B <= INT_BITS - 2, where
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52 | INT_BITS is the number of useful bits in an int. GNU code can
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53 | assume that INT_BITS is at least 32.
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54 |
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55 | ISO C99 says that A >> B is implementation-defined if A < 0. Some
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56 | implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift
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57 | right in the usual way when A < 0, so SHR falls back on division if
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58 | ordinary A >> B doesn't seem to be the usual signed shift. */
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59 | #define SHR(a, b) \
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60 | (-1 >> 1 == -1 \
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61 | ? (a) >> (b) \
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62 | : (a) / (1 << (b)) - ((a) % (1 << (b)) < 0))
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63 |
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64 | /* The extra casts in the following macros work around compiler bugs,
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65 | e.g., in Cray C 5.0.3.0. */
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66 |
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67 | /* True if the arithmetic type T is an integer type. bool counts as
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68 | an integer. */
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69 | #define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
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70 |
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71 | /* True if negative values of the signed integer type T use two's
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72 | complement, ones' complement, or signed magnitude representation,
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73 | respectively. Much GNU code assumes two's complement, but some
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74 | people like to be portable to all possible C hosts. */
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75 | #define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
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76 | #define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
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77 | #define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
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78 |
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79 | /* True if the arithmetic type T is signed. */
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80 | #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
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81 |
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82 | /* The maximum and minimum values for the integer type T. These
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83 | macros have undefined behavior if T is signed and has padding bits.
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84 | If this is a problem for you, please let us know how to fix it for
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85 | your host. */
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86 | #define TYPE_MINIMUM(t) \
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87 | ((t) (! TYPE_SIGNED (t) \
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88 | ? (t) 0 \
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89 | : TYPE_SIGNED_MAGNITUDE (t) \
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90 | ? ~ (t) 0 \
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91 | : ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
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92 | #define TYPE_MAXIMUM(t) \
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93 | ((t) (! TYPE_SIGNED (t) \
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94 | ? (t) -1 \
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95 | : ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))
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96 |
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97 | #ifndef TIME_T_MIN
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98 | # define TIME_T_MIN TYPE_MINIMUM (time_t)
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99 | #endif
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100 | #ifndef TIME_T_MAX
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101 | # define TIME_T_MAX TYPE_MAXIMUM (time_t)
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102 | #endif
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103 | #define TIME_T_MIDPOINT (SHR (TIME_T_MIN + TIME_T_MAX, 1) + 1)
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104 |
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105 | /* Verify a requirement at compile-time (unlike assert, which is runtime). */
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106 | #define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
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107 |
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108 | verify (time_t_is_integer, TYPE_IS_INTEGER (time_t));
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109 | verify (twos_complement_arithmetic, TYPE_TWOS_COMPLEMENT (int));
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110 | /* The code also assumes that signed integer overflow silently wraps
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111 | around, but this assumption can't be stated without causing a
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112 | diagnostic on some hosts. */
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113 |
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114 | #define EPOCH_YEAR 1970
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115 | #define TM_YEAR_BASE 1900
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116 | verify (base_year_is_a_multiple_of_100, TM_YEAR_BASE % 100 == 0);
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117 |
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118 | /* Return 1 if YEAR + TM_YEAR_BASE is a leap year. */
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119 | static inline int
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120 | leapyear (long int year)
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121 | {
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122 | /* Don't add YEAR to TM_YEAR_BASE, as that might overflow.
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123 | Also, work even if YEAR is negative. */
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124 | return
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125 | ((year & 3) == 0
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126 | && (year % 100 != 0
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127 | || ((year / 100) & 3) == (- (TM_YEAR_BASE / 100) & 3)));
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128 | }
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129 |
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130 | /* How many days come before each month (0-12). */
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131 | #ifndef _LIBC
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132 | static
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133 | #endif
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134 | const unsigned short int __mon_yday[2][13] =
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135 | {
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136 | /* Normal years. */
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137 | { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
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138 | /* Leap years. */
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139 | { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
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140 | };
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141 |
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142 |
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143 | #ifndef _LIBC
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144 | /* Portable standalone applications should supply a "time_r.h" that
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145 | declares a POSIX-compliant localtime_r, for the benefit of older
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146 | implementations that lack localtime_r or have a nonstandard one.
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147 | See the gnulib time_r module for one way to implement this. */
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148 | # include "time_r.h"
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149 | # undef __localtime_r
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150 | # define __localtime_r localtime_r
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151 | # define __mktime_internal mktime_internal
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152 | #endif
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153 |
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154 | /* Return an integer value measuring (YEAR1-YDAY1 HOUR1:MIN1:SEC1) -
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155 | (YEAR0-YDAY0 HOUR0:MIN0:SEC0) in seconds, assuming that the clocks
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156 | were not adjusted between the time stamps.
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157 |
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158 | The YEAR values uses the same numbering as TP->tm_year. Values
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159 | need not be in the usual range. However, YEAR1 must not be less
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160 | than 2 * INT_MIN or greater than 2 * INT_MAX.
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161 |
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162 | The result may overflow. It is the caller's responsibility to
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163 | detect overflow. */
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164 |
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165 | static inline time_t
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166 | ydhms_diff (long int year1, long int yday1, int hour1, int min1, int sec1,
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167 | int year0, int yday0, int hour0, int min0, int sec0)
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168 | {
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169 | verify (C99_integer_division, -1 / 2 == 0);
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170 | verify (long_int_year_and_yday_are_wide_enough,
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171 | INT_MAX <= LONG_MAX / 2 || TIME_T_MAX <= UINT_MAX);
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172 |
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173 | /* Compute intervening leap days correctly even if year is negative.
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174 | Take care to avoid integer overflow here. */
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175 | int a4 = SHR (year1, 2) + SHR (TM_YEAR_BASE, 2) - ! (year1 & 3);
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176 | int b4 = SHR (year0, 2) + SHR (TM_YEAR_BASE, 2) - ! (year0 & 3);
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177 | int a100 = a4 / 25 - (a4 % 25 < 0);
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178 | int b100 = b4 / 25 - (b4 % 25 < 0);
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179 | int a400 = SHR (a100, 2);
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180 | int b400 = SHR (b100, 2);
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181 | int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);
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182 |
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183 | /* Compute the desired time in time_t precision. Overflow might
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184 | occur here. */
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185 | time_t tyear1 = year1;
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186 | time_t years = tyear1 - year0;
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187 | time_t days = 365 * years + yday1 - yday0 + intervening_leap_days;
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188 | time_t hours = 24 * days + hour1 - hour0;
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189 | time_t minutes = 60 * hours + min1 - min0;
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190 | time_t seconds = 60 * minutes + sec1 - sec0;
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191 | return seconds;
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192 | }
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193 |
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194 |
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195 | /* Return a time_t value corresponding to (YEAR-YDAY HOUR:MIN:SEC),
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196 | assuming that *T corresponds to *TP and that no clock adjustments
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197 | occurred between *TP and the desired time.
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198 | If TP is null, return a value not equal to *T; this avoids false matches.
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199 | If overflow occurs, yield the minimal or maximal value, except do not
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200 | yield a value equal to *T. */
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201 | static time_t
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202 | guess_time_tm (long int year, long int yday, int hour, int min, int sec,
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203 | const time_t *t, const struct tm *tp)
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204 | {
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205 | if (tp)
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206 | {
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207 | time_t d = ydhms_diff (year, yday, hour, min, sec,
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208 | tp->tm_year, tp->tm_yday,
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209 | tp->tm_hour, tp->tm_min, tp->tm_sec);
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210 | time_t t1 = *t + d;
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211 | if ((t1 < *t) == (TYPE_SIGNED (time_t) ? d < 0 : TIME_T_MAX / 2 < d))
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212 | return t1;
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213 | }
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214 |
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215 | /* Overflow occurred one way or another. Return the nearest result
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216 | that is actually in range, except don't report a zero difference
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217 | if the actual difference is nonzero, as that would cause a false
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218 | match; and don't oscillate between two values, as that would
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219 | confuse the spring-forward gap detector. */
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220 | return (*t < TIME_T_MIDPOINT
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221 | ? (*t <= TIME_T_MIN + 1 ? *t + 1 : TIME_T_MIN)
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222 | : (TIME_T_MAX - 1 <= *t ? *t - 1 : TIME_T_MAX));
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223 | }
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224 |
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225 | /* Use CONVERT to convert *T to a broken down time in *TP.
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226 | If *T is out of range for conversion, adjust it so that
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227 | it is the nearest in-range value and then convert that. */
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228 | static struct tm *
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229 | ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
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230 | time_t *t, struct tm *tp)
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231 | {
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232 | struct tm *r = convert (t, tp);
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233 |
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234 | if (!r && *t)
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235 | {
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236 | time_t bad = *t;
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237 | time_t ok = 0;
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238 |
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239 | /* BAD is a known unconvertible time_t, and OK is a known good one.
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240 | Use binary search to narrow the range between BAD and OK until
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241 | they differ by 1. */
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242 | while (bad != ok + (bad < 0 ? -1 : 1))
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243 | {
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244 | time_t mid = *t = (bad < 0
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245 | ? bad + ((ok - bad) >> 1)
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246 | : ok + ((bad - ok) >> 1));
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247 | r = convert (t, tp);
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248 | if (r)
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249 | ok = mid;
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250 | else
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251 | bad = mid;
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252 | }
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253 |
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254 | if (!r && ok)
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255 | {
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256 | /* The last conversion attempt failed;
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257 | revert to the most recent successful attempt. */
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258 | *t = ok;
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259 | r = convert (t, tp);
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260 | }
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261 | }
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262 |
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263 | return r;
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264 | }
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265 |
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266 |
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267 | /* Convert *TP to a time_t value, inverting
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268 | the monotonic and mostly-unit-linear conversion function CONVERT.
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269 | Use *OFFSET to keep track of a guess at the offset of the result,
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270 | compared to what the result would be for UTC without leap seconds.
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271 | If *OFFSET's guess is correct, only one CONVERT call is needed.
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272 | This function is external because it is used also by timegm.c. */
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273 | time_t
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274 | __mktime_internal (struct tm *tp,
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275 | struct tm *(*convert) (const time_t *, struct tm *),
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276 | time_t *offset)
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277 | {
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278 | time_t t, gt, t0, t1, t2;
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279 | struct tm tm;
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280 |
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281 | /* The maximum number of probes (calls to CONVERT) should be enough
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282 | to handle any combinations of time zone rule changes, solar time,
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283 | leap seconds, and oscillations around a spring-forward gap.
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284 | POSIX.1 prohibits leap seconds, but some hosts have them anyway. */
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285 | int remaining_probes = 6;
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286 |
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287 | /* Time requested. Copy it in case CONVERT modifies *TP; this can
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288 | occur if TP is localtime's returned value and CONVERT is localtime. */
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289 | int sec = tp->tm_sec;
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290 | int min = tp->tm_min;
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291 | int hour = tp->tm_hour;
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292 | int mday = tp->tm_mday;
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293 | int mon = tp->tm_mon;
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294 | int year_requested = tp->tm_year;
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295 | int isdst = tp->tm_isdst;
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296 |
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297 | /* 1 if the previous probe was DST. */
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298 | int dst2;
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299 |
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300 | /* Ensure that mon is in range, and set year accordingly. */
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301 | 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 |
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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 |
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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])
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316 | - 1);
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317 | long int lmday = mday;
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318 | long int yday = mon_yday + lmday;
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319 |
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320 | time_t guessed_offset = *offset;
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321 |
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322 | int sec_requested = sec;
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323 |
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324 | if (LEAP_SECONDS_POSSIBLE)
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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;
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330 | if (59 < sec)
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331 | sec = 59;
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332 | }
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333 |
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334 | /* Invert CONVERT by probing. First assume the same offset as last
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335 | time. */
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336 |
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337 | t0 = ydhms_diff (year, yday, hour, min, sec,
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338 | EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, - guessed_offset);
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339 |
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340 | if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3)
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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 |
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348 | /* Approximate log base 2 of the number of time units per
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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;
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355 | int ALOG2_MINUTES_PER_BIENNIUM = 20;
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356 | int ALOG2_HOURS_PER_BIENNIUM = 14;
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357 | int ALOG2_DAYS_PER_BIENNIUM = 10;
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358 | int LOG2_YEARS_PER_BIENNIUM = 1;
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359 |
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360 | int approx_requested_biennia =
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361 | (SHR (year_requested, LOG2_YEARS_PER_BIENNIUM)
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362 | - SHR (EPOCH_YEAR - TM_YEAR_BASE, LOG2_YEARS_PER_BIENNIUM)
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363 | + SHR (mday, ALOG2_DAYS_PER_BIENNIUM)
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364 | + SHR (hour, ALOG2_HOURS_PER_BIENNIUM)
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365 | + SHR (min, ALOG2_MINUTES_PER_BIENNIUM)
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366 | + (LEAP_SECONDS_POSSIBLE
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367 | ? 0
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368 | : SHR (sec, ALOG2_SECONDS_PER_BIENNIUM)));
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369 |
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370 | int approx_biennia = SHR (t0, ALOG2_SECONDS_PER_BIENNIUM);
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371 | int diff = approx_biennia - approx_requested_biennia;
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372 | int abs_diff = diff < 0 ? - diff : diff;
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373 |
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374 | /* IRIX 4.0.5 cc miscaculates TIME_T_MIN / 3: it erroneously
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375 | gives a positive value of 715827882. Setting a variable
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376 | first then doing math on it seems to work.
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377 | (ghazi@caip.rutgers.edu) */
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378 | time_t time_t_max = TIME_T_MAX;
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379 | time_t time_t_min = TIME_T_MIN;
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380 | time_t overflow_threshold =
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381 | (time_t_max / 3 - time_t_min / 3) >> ALOG2_SECONDS_PER_BIENNIUM;
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382 |
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383 | if (overflow_threshold < abs_diff)
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384 | {
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385 | /* Overflow occurred. Try repairing it; this might work if
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386 | the time zone offset is enough to undo the overflow. */
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387 | time_t repaired_t0 = -1 - t0;
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388 | approx_biennia = SHR (repaired_t0, ALOG2_SECONDS_PER_BIENNIUM);
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389 | diff = approx_biennia - approx_requested_biennia;
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390 | abs_diff = diff < 0 ? - diff : diff;
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391 | if (overflow_threshold < abs_diff)
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392 | return -1;
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393 | guessed_offset += repaired_t0 - t0;
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394 | t0 = repaired_t0;
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395 | }
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396 | }
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397 |
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398 | /* Repeatedly use the error to improve the guess. */
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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 | |
---|
527 |
|
---|
528 | #if DEBUG
|
---|
529 |
|
---|
530 | static int
|
---|
531 | not_equal_tm (const struct tm *a, const struct tm *b)
|
---|
532 | {
|
---|
533 | return ((a->tm_sec ^ b->tm_sec)
|
---|
534 | | (a->tm_min ^ b->tm_min)
|
---|
535 | | (a->tm_hour ^ b->tm_hour)
|
---|
536 | | (a->tm_mday ^ b->tm_mday)
|
---|
537 | | (a->tm_mon ^ b->tm_mon)
|
---|
538 | | (a->tm_year ^ b->tm_year)
|
---|
539 | | (a->tm_yday ^ b->tm_yday)
|
---|
540 | | (a->tm_isdst ^ b->tm_isdst));
|
---|
541 | }
|
---|
542 |
|
---|
543 | static void
|
---|
544 | print_tm (const struct tm *tp)
|
---|
545 | {
|
---|
546 | if (tp)
|
---|
547 | printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
|
---|
548 | tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
|
---|
549 | tp->tm_hour, tp->tm_min, tp->tm_sec,
|
---|
550 | tp->tm_yday, tp->tm_wday, tp->tm_isdst);
|
---|
551 | else
|
---|
552 | printf ("0");
|
---|
553 | }
|
---|
554 |
|
---|
555 | static int
|
---|
556 | check_result (time_t tk, struct tm tmk, time_t tl, const struct tm *lt)
|
---|
557 | {
|
---|
558 | if (tk != tl || !lt || not_equal_tm (&tmk, lt))
|
---|
559 | {
|
---|
560 | printf ("mktime (");
|
---|
561 | print_tm (lt);
|
---|
562 | printf (")\nyields (");
|
---|
563 | print_tm (&tmk);
|
---|
564 | printf (") == %ld, should be %ld\n", (long int) tk, (long int) tl);
|
---|
565 | return 1;
|
---|
566 | }
|
---|
567 |
|
---|
568 | return 0;
|
---|
569 | }
|
---|
570 |
|
---|
571 | int
|
---|
572 | main (int argc, char **argv)
|
---|
573 | {
|
---|
574 | int status = 0;
|
---|
575 | struct tm tm, tmk, tml;
|
---|
576 | struct tm *lt;
|
---|
577 | time_t tk, tl, tl1;
|
---|
578 | char trailer;
|
---|
579 |
|
---|
580 | if ((argc == 3 || argc == 4)
|
---|
581 | && (sscanf (argv[1], "%d-%d-%d%c",
|
---|
582 | &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer)
|
---|
583 | == 3)
|
---|
584 | && (sscanf (argv[2], "%d:%d:%d%c",
|
---|
585 | &tm.tm_hour, &tm.tm_min, &tm.tm_sec, &trailer)
|
---|
586 | == 3))
|
---|
587 | {
|
---|
588 | tm.tm_year -= TM_YEAR_BASE;
|
---|
589 | tm.tm_mon--;
|
---|
590 | tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]);
|
---|
591 | tmk = tm;
|
---|
592 | tl = mktime (&tmk);
|
---|
593 | lt = localtime (&tl);
|
---|
594 | if (lt)
|
---|
595 | {
|
---|
596 | tml = *lt;
|
---|
597 | lt = &tml;
|
---|
598 | }
|
---|
599 | printf ("mktime returns %ld == ", (long int) tl);
|
---|
600 | print_tm (&tmk);
|
---|
601 | printf ("\n");
|
---|
602 | status = check_result (tl, tmk, tl, lt);
|
---|
603 | }
|
---|
604 | else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0))
|
---|
605 | {
|
---|
606 | time_t from = atol (argv[1]);
|
---|
607 | time_t by = atol (argv[2]);
|
---|
608 | time_t to = atol (argv[3]);
|
---|
609 |
|
---|
610 | if (argc == 4)
|
---|
611 | for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
|
---|
612 | {
|
---|
613 | lt = localtime (&tl);
|
---|
614 | if (lt)
|
---|
615 | {
|
---|
616 | tmk = tml = *lt;
|
---|
617 | tk = mktime (&tmk);
|
---|
618 | status |= check_result (tk, tmk, tl, &tml);
|
---|
619 | }
|
---|
620 | else
|
---|
621 | {
|
---|
622 | printf ("localtime (%ld) yields 0\n", (long int) tl);
|
---|
623 | status = 1;
|
---|
624 | }
|
---|
625 | tl1 = tl + by;
|
---|
626 | if ((tl1 < tl) != (by < 0))
|
---|
627 | break;
|
---|
628 | }
|
---|
629 | else
|
---|
630 | for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
|
---|
631 | {
|
---|
632 | /* Null benchmark. */
|
---|
633 | lt = localtime (&tl);
|
---|
634 | if (lt)
|
---|
635 | {
|
---|
636 | tmk = tml = *lt;
|
---|
637 | tk = tl;
|
---|
638 | status |= check_result (tk, tmk, tl, &tml);
|
---|
639 | }
|
---|
640 | else
|
---|
641 | {
|
---|
642 | printf ("localtime (%ld) yields 0\n", (long int) tl);
|
---|
643 | status = 1;
|
---|
644 | }
|
---|
645 | tl1 = tl + by;
|
---|
646 | if ((tl1 < tl) != (by < 0))
|
---|
647 | break;
|
---|
648 | }
|
---|
649 | }
|
---|
650 | else
|
---|
651 | printf ("Usage:\
|
---|
652 | \t%s YYYY-MM-DD HH:MM:SS [ISDST] # Test given time.\n\
|
---|
653 | \t%s FROM BY TO # Test values FROM, FROM+BY, ..., TO.\n\
|
---|
654 | \t%s FROM BY TO - # Do not test those values (for benchmark).\n",
|
---|
655 | argv[0], argv[0], argv[0]);
|
---|
656 |
|
---|
657 | return status;
|
---|
658 | }
|
---|
659 |
|
---|
660 | #endif /* DEBUG */
|
---|
661 | |
---|
662 |
|
---|
663 | /*
|
---|
664 | Local Variables:
|
---|
665 | compile-command: "gcc -DDEBUG -Wall -W -O -g mktime.c -o mktime"
|
---|
666 | End:
|
---|
667 | */
|
---|