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2.5-18.1

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This commit is contained in:
Jakub Jelinek
2007-07-12 18:26:36 +00:00
parent 7d58530341
commit 0ecb606cb6
6215 changed files with 494638 additions and 305010 deletions
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73
time/mktime.c
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@ -1,7 +1,7 @@
/* Convert a `struct tm' to a time_t value.
Copyright (C) 1993-1999, 2002, 2003, 2004 Free Software Foundation, Inc.
Copyright (C) 1993-1999, 2002-2005, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Paul Eggert (eggert@twinsun.com).
Contributed by Paul Eggert <eggert@twinsun.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@ -38,10 +38,11 @@
#include <limits.h>
#include <string.h> /* For the real memcpy prototype. */
#if DEBUG
# include <stdio.h>
# include <stdlib.h>
# include <string.h>
/* Make it work even if the system's libc has its own mktime routine. */
# define mktime my_mktime
#endif /* DEBUG */
@ -61,13 +62,38 @@
? (a) >> (b) \
: (a) / (1 << (b)) - ((a) % (1 << (b)) < 0))
/* The extra casts work around common compiler bugs. */
/* The extra casts in the following macros work around compiler bugs,
e.g., in Cray C 5.0.3.0. */
/* True if the arithmetic type T is an integer type. bool counts as
an integer. */
#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
/* True if negative values of the signed integer type T use two's
complement, ones' complement, or signed magnitude representation,
respectively. Much GNU code assumes two's complement, but some
people like to be portable to all possible C hosts. */
#define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
#define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
#define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
/* True if the arithmetic type T is signed. */
#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
/* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
It is necessary at least when t == time_t. */
#define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
/* The maximum and minimum values for the integer type T. These
macros have undefined behavior if T is signed and has padding bits.
If this is a problem for you, please let us know how to fix it for
your host. */
#define TYPE_MINIMUM(t) \
((t) (! TYPE_SIGNED (t) \
? (t) 0 \
: TYPE_SIGNED_MAGNITUDE (t) \
? ~ (t) 0 \
: ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
#define TYPE_MAXIMUM(t) \
((t) (! TYPE_SIGNED (t) \
? (t) -1 \
: ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))
#ifndef TIME_T_MIN
# define TIME_T_MIN TYPE_MINIMUM (time_t)
@ -80,8 +106,8 @@
/* Verify a requirement at compile-time (unlike assert, which is runtime). */
#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
verify (time_t_is_integer, (time_t) 0.5 == 0);
verify (twos_complement_arithmetic, -1 == ~1 + 1);
verify (time_t_is_integer, TYPE_IS_INTEGER (time_t));
verify (twos_complement_arithmetic, TYPE_TWOS_COMPLEMENT (int));
/* The code also assumes that signed integer overflow silently wraps
around, but this assumption can't be stated without causing a
diagnostic on some hosts. */
@ -190,10 +216,11 @@ guess_time_tm (long int year, long int yday, int hour, int min, int sec,
/* Overflow occurred one way or another. Return the nearest result
that is actually in range, except don't report a zero difference
if the actual difference is nonzero, as that would cause a false
match. */
match; and don't oscillate between two values, as that would
confuse the spring-forward gap detector. */
return (*t < TIME_T_MIDPOINT
? TIME_T_MIN + (*t == TIME_T_MIN)
: TIME_T_MAX - (*t == TIME_T_MAX));
? (*t <= TIME_T_MIN + 1 ? *t + 1 : TIME_T_MIN)
: (TIME_T_MAX - 1 <= *t ? *t - 1 : TIME_T_MAX));
}
/* Use CONVERT to convert *T to a broken down time in *TP.
@ -203,13 +230,12 @@ static struct tm *
ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
time_t *t, struct tm *tp)
{
struct tm *r;
struct tm *r = convert (t, tp);
if (! (r = (*convert) (t, tp)) && *t)
if (!r && *t)
{
time_t bad = *t;
time_t ok = 0;
struct tm tm;
/* BAD is a known unconvertible time_t, and OK is a known good one.
Use binary search to narrow the range between BAD and OK until
@ -219,11 +245,9 @@ ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
time_t mid = *t = (bad < 0
? bad + ((ok - bad) >> 1)
: ok + ((bad - ok) >> 1));
if ((r = (*convert) (t, tp)))
{
tm = *r;
ok = mid;
}
r = convert (t, tp);
if (r)
ok = mid;
else
bad = mid;
}
@ -233,8 +257,7 @@ ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
/* The last conversion attempt failed;
revert to the most recent successful attempt. */
*t = ok;
*tp = tm;
r = tp;
r = convert (t, tp);
}
}
@ -463,7 +486,7 @@ __mktime_internal (struct tm *tp,
t2 = t1 + sec_adjustment;
if (((t1 < t) != (sec_requested < 0))
| ((t2 < t1) != (sec_adjustment < 0))
| ! (*convert) (&t2, &tm))
| ! convert (&t2, &tm))
return -1;
t = t2;
}