glibc/time/difftime.c
Ulrich Drepper 6bc31da01b update from main archive 970101
Wed Jan  1 15:15:00 1997  Ulrich Drepper  <drepper@cygnus.com>

	* libio/Makefile (routines): Add fcloseall.
	* libio/fcloseall.c: New file.
	* libio/stdio.h [__USE_GNU]: Add prototype for fcloseall.
	* libio/iofclose.c: Don't close all streams when argument is NULL.

	* stdio/Makefile (routines): Add fcloseall.
	* stdio/fcloseall.c: New file.
	* stdio/stdio.h [__USE_GNU]: Add prototype for fcloseall.
	* stdio/fclose.c: Don't close all streams when argument is NULL.

	* manual/stdio.texi: Document fcloseall.

	* sysdeps/generic/abort.c: Call __fcloseall instead of fclose with
	NULL argument.

	* socket/sys/un.h (SUN_LEN): Add cast.

	* sunrpc/auth_unix.c (authunix_create): Change parameter types
	of uid, gid, and aup_gids to uid_t and gid_t respectively.
	(authunix_create_default): Likewise.
	(authunix_refresh): Correct cast for aup_gids assignment.
	* sunrpc/rpc/auth.h (authunix_create): Correct types in declaration.
	* sunrpc/rpc/auth_unix.h (struct authunix_parms): Correct field
	types to uid_t and gid_t respectively.
	(struct short_hand_verf): Likewise.
	Reported by Andreas Schwab.

	* sysdeps/ieee754/Makefile: New file.  Make sure ieee754.h gets
	installed.
	* sysdeps/ieee754/ieee754.h: Protect against multiple inclusion and
	use in C++ programs.

	* sysdeps/libm-i387/e_pow.S: New file.  Optimized ix87 assembler
	version of pow() function.
	* sysdeps/libm-i387/e_powf.S: New file.  Float version.
	* sysdeps/libm-i387/e_powl.S: New file.  Long double version.

	* sysdeps/libm-i387/s_expm1.S: New file.  Optimized ix87 assembler
	version of expm1() function.
	* sysdeps/libm-i387/s_expm1f.S: New file.  Float version.
	* sysdeps/libm-i387/s_expm1l.S: New file.  Long double version.

	* sysdeps/libm-i387/e_exp.S: Optimize handling of +-Inf.
	Better handling of computation stack from current NetBSD sources.
	* sysdeps/libm-i387/e_expf.S: Likewise.
	* sysdeps/libm-i387/e_expl.S: Likewise.

	* sysdeps/libm-i387/e_log.S: Use fstp instead of fincstp.
	* sysdeps/libm-i387/e_logf.S: Likewise.
	* sysdeps/libm-i387/e_logl.S: Likewise.
	* sysdeps/libm-i387/e_log10.S: Likewise.
	* sysdeps/libm-i387/e_log10f.S: Likewise.
	* sysdeps/libm-i387/e_log10l.S: Likewise.
	* sysdeps/libm-i387/s_asinh.S: Likewise.
	* sysdeps/libm-i387/s_asinhf.S: Likewise.
	* sysdeps/libm-i387/s_asinhl.S: Likewise.
	* sysdeps/libm-i387/s_significandl.S: Likewise.

	* sysdeps/libm-i387/s_ceil.S: Don't create stack frame.  Modify
	stack pointer directly.  Use 32 bit instead of 16 bit operations.
	* sysdeps/libm-i387/s_ceilf.S: Likewise.
	* sysdeps/libm-i387/s_ceill.S: Likewise.
	* sysdeps/libm-i387/s_floor.S: Likewise.
	* sysdeps/libm-i387/s_floorf.S: Likewise.
	* sysdeps/libm-i387/s_floorl.S: Likewise.

	* sysdeps/libm-ieee754/e_coshf.c (huge): Don't declare volatile.
	* sysdeps/libm-ieee754/e_expf.c: Likewise.
	* sysdeps/libm-ieee754/e_powf.c: Likewise.
	From current NetBSD sources.

	* sysdeps/libm-ieee754/e_hypot.c (__ieee754_hypot): Don't initialize
	`a' and `b' in definition.
	* sysdeps/libm-ieee754/e_hypotf.c: Likewise.

	* sysdeps/libm-ieee754/e_hypotl.c: New file.  Long double
	implementation.
	* sysdeps/libm-ieee754/e_sinhl.c: New file.  Long double
	implementation.
	* sysdeps/stub/e_hypotl.c: Removed.  We have a real version now.
	* sysdeps/stub/e_sinhl.c: Removed.

	* sysdeps/posix/sigpause.c (__sigpause): Use sigdelset instead of
	sigaddset.  Reported by Andreas Schwab.
	(__default_sigpause): New function.  Call __sigpause as BSD version.
	Make this the default function by providing alias sigpause.
	* sysdeps/stub/sigpause.c (__default_sigpause): New funciton.
	Simply fail.  Provide alias sigpause.

Wed Jan  1 12:34:54 1997  Ulrich Drepper  <drepper@cygnus.com>

	* po/es.po: Update for glibc-1.98.
	* po/fr.po: Likewise.
	* po/sv.po: New file.  Swedish translation.

Wed Jan  1 12:18:07 1997   MacGyver  <macgyver@tos.net>

	* values.h: Fix typos: use SHRT_MAX but SHORT_MAX and SHRT_MIN but
	SHORT_MIN.

Tue Dec 24 23:10:21 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* Makefile: Replace `stubs.h' by `gnu/stubs.h'.
	* features.h: Include <gnu/stubs.h> instead of <stubs.h>.

Tue Dec 24 22:16:55 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* Makefile (subdirs): Move `elf' last so that librtld.so isn't
	relinked in the `make others' pass if an add-on adds something to
	libc.

Mon Dec 23 21:23:16 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/abort-instr.h: New File.

Mon Dec 23 21:16:38 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/Makefile ($(subdir)=elf): Define CFLAGS-rtld.c
	to prevent warning.

Mon Dec 23 21:14:22 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* resolv/Makefile (subdirs-dirs): Define.

Mon Dec 23 20:56:49 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/gnu/utmpbits.h (struct utmp): Fix padding.

Mon Dec 30 11:05:11 1996  Ulrich Drepper  <drepper@cygnus.com>

	Update from ADO tzcode1996o.
	* time/difftime.c: De-ANSI-declfy.  Simplify computation of hibit
	according to ADO version.
	* time/zic.c: Correct typo is message.

	Update from ADO tzdata1996n.
	* time/asia: Updated.
	* time/australasia: Likewise.
	* time/europe: Likewise.
	* time/northamerica: Likewise.
	* time/southamerica: Likewise.
1997-01-01 15:28:18 +00:00

67 lines
2.7 KiB
C

/* Copyright (C) 1991, 1994, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <time.h>
#include <values.h>
/* Return the difference between TIME1 and TIME0. */
double
difftime (time1, time0)
time_t time1;
time_t time0;
{
/* Algorithm courtesy Paul Eggert (eggert@twinsun.com). */
time_t delta, hibit;
if (sizeof (time_t) < sizeof (double))
return (double) time1 - (double) time0;
if (sizeof (time_t) < sizeof (long double))
return (long double) time1 - (long double) time0;
if (time1 < time0)
return - difftime (time0, time1);
/* As much as possible, avoid loss of precision by computing the
difference before converting to double. */
delta = time1 - time0;
if (delta >= 0)
return delta;
/* Repair delta overflow. */
hibit = (~ (time_t) 0) << (_TYPEBITS (time_t) - 1);
/* The following expression rounds twice, which means the result may not
be the closest to the true answer. For example, suppose time_t is
64-bit signed int, long_double is IEEE 754 double with default
rounding, time1 = 9223372036854775807 and time0 = -1536. Then the
true difference is 9223372036854777343, which rounds to
9223372036854777856 with a total error of 513. But delta overflows to
-9223372036854774273, which rounds to -9223372036854774784, and
correcting this by subtracting 2 * (long_double) hibit (i.e. by adding
2**64 = 18446744073709551616) yields 9223372036854776832, which rounds
to 9223372036854775808 with a total error of 1535 instead. This
problem occurs only with very large differences. It's too painful to
fix this portably. We are not alone in this problem; many C compilers
round twice when converting large unsigned types to small floating
types, so if time_t is unsigned the "return delta" above has the same
double-rounding problem. */
return delta - 2 * (long double) hibit;
}