Keep these functions compatible with Gnulib while adding
__time64_t support. The basic idea is to move private API
declarations from include/time.h to time/mktime-internal.h, since
the former file cannot easily be shared with Gnulib whereas the
latter can.
Also, do some other minor cleanup while in the neighborhood.
* include/time.h: Include stdbool.h, time/mktime-internal.h.
(__mktime_internal): Move this prototype to time/mktime-internal.h,
since Gnulib needs it.
(__localtime64_r, __gmtime64_r) [__TIMESIZE == 64]:
Move these macros to time/mktime-internal.h, since Gnulib needs them.
(__mktime64, __timegm64) [__TIMESIZE != 64]: New prototypes.
(in_time_t_range): New static function.
* posix/bits/types.h (__time64_t) [__TIMESIZE == 64 && !defined __LIBC]:
Do not define as a macro in this case, so that portable code is
less tempted to use __time64_t.
* time/mktime-internal.h: Rewrite so that it does both glibc
and Gnulib work. Include time.h if not _LIBC.
(mktime_offset_t) [!_LIBC]: Define for gnulib.
(__time64_t, __gmtime64_r, __localtime64_r, __mktime64, __timegm64)
[!_LIBC || __TIMESIZE == 64]: New macros, mostly moved here
from include/time.h.
(__gmtime_r, __localtime_r, __mktime_internal) [!_LIBC]:
New macros, taken from GNulib.
(__mktime_internal): New prototype, moved here from include/time.h.
* time/mktime.c (mktime_min, mktime_max, convert_time)
(ranged_convert, __mktime_internal, __mktime64):
* time/timegm.c (__timegm64):
Use __time64_t, not time_t.
* time/mktime.c: Stop worrying about whether time_t is floating-point.
(__mktime64) [! (_LIBC && __TIMESIZE != 64)]:
Rename from mktime.
(mktime) [_LIBC && __TIMESIZE != 64]: New function.
* time/timegm.c [!_LIBC]: Include libc-config.h, not config.h,
for libc_hidden_def.
Include errno.h.
(__timegm64) [! (_LIBC && __TIMESIZE != 64)]:
Rename from timegm.
(timegm) [_LIBC && __TIMESIZE != 64]: New function.
First cut at publicizing __time64_t
The DEBUG_MKTIME code no longer works in glibc or in Gnulib.
And it’s no longer needed now that glibc and Gnulib both have
their own testing mechanisms for mktime.
* time/mktime.c (DEBUG_MKTIME): Remove. All uses removed.
[BZ#23789]
mktime was not properly reporting failures when the underlying
localtime_r fails with errno != EOVERFLOW; it incorrectly treated
them like EOVERFLOW failures, and set errno to EOVERFLOW.
The problem could happen on non-glibc platforms, with Gnulib.
* time/mktime.c (guess_time_tm): Remove, replacing with ...
(tm_diff): ... this simpler function, which does not change errno.
All callers changed to deal with errno themselves.
(ranged_convert, __mktime_internal): Return failure immediately if
the underlying function reports any failure other than EOVERFLOW.
(__mktime_internal): Set errno to EOVERFLOW if the spring-forward
gap code fails.
[BZ#23789]
* time/mktime.c (ranged_convert): On 32-bit platforms, don’t
mishandle a DST transition that jumps over the Y2038 boundary.
No such DST transitions are known so this is only a theoretical
bug, but we might as well do things right.
[BZ#23789]
* time/mktime.c (long_int): Now 4⨯ int, not just 3⨯.
This is so that we can add tm_diff results to a previous guess,
which will be useful in a later patch.
[BZ#23789]
* time/mktime.c [!_LIBC && !DEBUG_MKTIME]:
Include libc-config.h, not config.h, for __set_errno.
(guess_time_tm, __mktime_internal): Set errno to EOVERFLOW on overflow.
[BZ#23745]
This fix affects only Gnulib. Problem discovered when
mktime.c was used as part of Gnulib in bleeding-edge Coreutils.
* time/mktime.c:
(my_tzset) [!_LIBC && !NEED_MKTIME_WORKING && !NEED_MKTIME_WINDOWS]:
Do not define since it is not used. Defining an unused static
function prompts a warning from GCC when Coreutils is configured
with --enable-gcc-warnings.
[BZ #23603][BZ #16346]
This fixes some obscure problems with integer overflow.
Although it looks scary, it is almost all a byte-for-byte copy
from Gnulib, and the Gnulib code has been tested reasonably well.
* include/intprops.h: New file, copied from Gnulib.
* include/verify.h, time/mktime-internal.h:
New tiny files, simplified from Gnulib.
* time/mktime.c: Copy from Gnulib. This has the following changes:
Do not include config.h if DEBUG_MKTIME is nonzero.
Include stdbool.h, intprops.h, verify.h.
Include string.h only if needed.
Include stdlib.h on MS-Windows.
Include mktime-internal.h.
(DEBUG_MKTIME): Default to 0, and simplify later uses.
(NEED_MKTIME_INTERNAL, NEED_MKTIME_WINDOWS)
(NEED_MKTIME_WORKING): Give default values to pacify -Wundef,
which glibc uses. Default NEED_MKTIME_WORKING to DEBUG_MKTIME, to
simplify later conditionals; default the others to zero. Use
these conditionals to express only the code needed on the current
platform. In uses of these conditionals, explicitly spell out how
_LIBC affects things, so it’s easier to review from a glibc
viewpoint.
(WRAPV): Remove; no longer needed now that we have
systematic overflow checking.
(my_tzset, __tzset) [!_LIBC]: New function and macro, to better
compartmentalize tzset issues. Move system-dependent tzsettish
code here from mktime.
(verify): Remove; now done by verify.h. All uses changed.
(long_int): Use a more-conservative definition, to avoid
integer overflow.
(SHR): Remove, replacing with ...
(shr): New function, which means we needn’t worry about side
effects in args, and conversion analysis is simpler.
(TYPE_IS_INTEGER, TYPE_TWOS_COMPLEMENT, TYPE_SIGNED, TYPE_MINIMUM)
(TYPE_MAXIMUM, TIME_T_MIN, TIME_T_MAX, TIME_T_MIDPOINT)
(time_t_avg, time_t_add_ok): Remove.
(mktime_min, mktime_max): New constants.
(leapyear, isdst_differ): Use bool for booleans.
(ydhms_diff, guess_time_tm, ranged_convert, __mktime_internal):
Use long_int, not time_t, for mktime differences.
(long_int_avg): New function, replacing time_t_avg.
INT_ADD_WRAPV replaces time_t_add_ok.
(guess_time_tm): 6th arg is now long_int, not time_t const *.
All uses changed.
(convert_time): New function.
(ranged_convert): Use it.
(__mktime_internal): Last arg now points to mktime_offset_t, not
time_t. All uses changed. This is a no-op on glibc, where
mktime_offset_t is always time_t. Use int, not time_t, for UTC
offset guess. Directly check for integer overflow instead of
using a heuristic that works only 99.9...% of the time.
Access *OFFSET only once, to avoid an unlikely race if the
compiler delays a load and if this cascades into a signed integer
overflow.
(mktime): Move tzsettish code to my_tzset, and move
localtime_offset to within mktime so that it doesn’t
need a separate ifdef.
(main) [DEBUG_MKTIME]: Speed up by using localtime_r
instead of localtime.
* time/timegm.c: Copy from Gnulib. This has the following changes:
Include mktime-internal.h.
[!_LIBC]: Include config.h and time.h. Do not include
timegm.h or time_r.h. Make __mktime_internal a macro,
and include mktime-internal.h to get its declaration.
(timegm): Temporary is now mktime_offset_t, not time_t.
This affects only Gnulib.
From the gnulib commit log:
commit e2646b0c6b5acda25e9ffeb4c12a5513a1e3b5ac
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Fri Jun 27 11:35:44 2014 -0700
mktime: merge #if/#ifdef usage from glibc
* lib/mktime.c: Use "#if defined DEBUG && DEBUG", not "#if DEBUG",
as that works with both Glibc's and Gnulib's style.
See thread starting at Siddhesh Poyarekar's bug report at:
http://lists.gnu.org/archive/html/bug-gnulib/2014-06/msg00102.html
* time/mktime.c (isdst_differ): New static function.
(__mktime_internal): No need to normalize tm_isdst now.
(__mktime_internal, not_equal_tm): Use isdst_differ to compare
tm_isdst values.
* time/mktime.c (TYPE_ONES_COMPLEMENT, TYPE_SIGNED_MAGNITUDE): Remove.
The code didn't really work on such machines anyway.
(TYPE_MINIMUM): Assume two's complement.
(twos_complement_arithmetic): Verify that long_int and time_t
are two's complement (or unsigned, in the latter case).
* time/mktime.c (verify): Move decl up.
(long_int): New type.
(leapyear, ydhms_diff, guess_time_tm, __mktime_internal): Use it,
to remove assumption in the code that 'long' is wide enough to
store year values. This assumption is not true on x32 and on
some non-glibc platforms.
* time/mktime.c (WRAPV): New macro.
(time_t_avg, time_t_add_ok, time_t_int_add_ok): New static functions.
(guess_time_tm, __mktime_internal): Do not assume that signed
integer overflow wraps around; modern compilers generate code
where this assumption is no longer valid.
2005-07-11 Derek R. Price <derek@ximbiot.com>
[BZ #1061]
* sysdeps/generic/glob.c (glob): Only a 0 return from
getlogin_r means success, according to POSIX 1003.2.
2005-06-23 Paul Eggert <eggert@cs.ucla.edu>
[BZ #1033]
* time/mktime.c: Import from gnulib.
The following macros are now consistent with other gnulib code.
This does not change mktime's behavior.
(TYPE_IS_INTEGER): New macro.
(time_t_is_integer): Use it.
(TYPE_TWOS_COMPLEMENT): New macro.
(twos_complement_arithmetic): Use it.
(TYPE_ONES_COMPLEMENT): New macro.
(TYPE_MINIMUM, TYPE_MAXIMUM): Now supports signed-magnitude.
mktime doesn't use this, but the code now matches other gnulib code.
(ranged_convert): Pacify GCC 4.0 in a different way, which
generates a few bytes less code.
(ranged_convert, __mktime_internal): When calling a function via a
pointer P, use P () rather than (*P) (), as we now assume C89 or
better.
implicitly used memcpy.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/truncate64.c
(truncate64): Use __truncate, not truncate.
(__have_no_truncate64): Renamed from have_no_truncate64.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/ftruncate64.c
(__have_no_truncate64): Renamed from have_no_truncate64.
2004-11-10 Paul Eggert <eggert@cs.ucla.edu>
[BZ #541]
* time/mktime.c (SHR): New macro, which is a portable
substitute for >> that should work even on Crays.
(TIME_T_MIDPOINT, ydhms_diff, __mktime_internal): Use it.
Problem reported by Mark D. Baushke in
<http://lists.gnu.org/archive/html/bug-gnulib/2004-11/msg00071.html>.
2004-10-27 Derek R. Price <derek@ximbiot.com>
[BZ #487] This change is imported from gnulib.
* time/mktime.c (not_equal_tm) [DEBUG]: Remove redundant check.
2004-10-24 Paul Eggert <eggert@cs.ucla.edu>
[BZ #473]
* time/tst-mktime.c (main): Don't assume that mktime fails
when given time stamps before 1970. It returns negative
time_t values instead, for compatibility with BSD.
* time/tst-mktime2.c: New file.
* time/Makefile (tests): Add it.
[BZ #473] Import from gnulib. Revamp to avoid several problems near
time_t extrema, and on hosts with 64-bit time_t and 32-bit int.
This fixes Debian bug 177940.
* time/mktime.c (TIME_T_MIDPOINT): New macro.
(ydhms_diff): Renamed from ydhms_tm_diff, with a new signature,
which avoids overflow problems on hosts with 64-bit time_t and
32-bit int. All callers changed. Now an inline function.
Verify at compile-time that long int is wide enough to avoid
these overflow problems.
(guess_time_tm): New function.
(__mktime_internal): Use it. Avoid overflow when computing yday on
hosts with 64-bit long and 32-bit int. Remove tests for 69;
no longer needed. Use if rather than #ifdef for LEAP_SECONDS_POSSIBLE
so that the code is checked by more compilers.
Do not rely on floating point to probe: stick to integer arithmetic,
to avoid potential porting problems.
Repair potential overflow correctly in the Southern Hemisphere.
(localtime_offset): Add a FIXME for the case where time_t is unsigned.
* time/mktime.c (leapyear, ydms_tm_diff): Year is of type
long int, not int, to avoid problems when tm_year == INT_MAX
and tm_mon > 12.
(__mktime_intenral): Compute year using long int arithmetic,
not int arithmetic, to avoid problems on hosts where time_t
and long are 64 bits but int is 32.
