view lib/intprops.h @ 5691:ec62790f0938

Factor int-properties macros into a single file, except for glibc-related files. * lib/intprops.h: New file. * lib/getloadavg.c: Include it instead of limits.h. (INT_STRLEN_BOUND): Remove. * lib/human.c: Include intprops.h. (group_number): Use INT_STRLEN_BOUND instead of rolling it ourself. * lib/human.h (LONGEST_HUMAN_READABLE): Use 146/485 rather than 302/1000. * lib/inttostr.h: Include intprops.h instead of limits.h. (INT_STRLEN_BOUND, INT_BUFSIZE_BOUND): Remove. * lib/mktime.c (TYPE_IS_INTEGER, TYPE_TWOS_COMPLEMENT): New macros, for consistency with intprops.h. (time_t_is_integer, twos_complement_arithmetic): Use them. * lib/sig2str.h: Include <signal.h>, intprops.h. (INT_STRLEN_BOUND): Remove. * lib/strftime.c (TYPE_SIGNED): Remove. (INT_STRLEN_BOUND): Switch to same implementation as intprops.h. * lib/strtol.c: Adjust comments to match intprops.h. * lib/userspec.c: Include intprops.h. (TYPE_SIGNED, TYPE_MINIMUM, TYPE_MAXIMUM): Remove. * lib/utimecmp.c, lib/xnanosleep.c, lib/xstrtol.c: Likewise. * lib/utimecmp.c (utimecmp): Use TYPE_IS_INTEGER, TYPE_TWOS_COMPLEMENT instead of rolling our own expressions. * lib/xstrtol.c: Include xstrtol.h first, to test interface. * modules/getloadavg (Files): Add lib/intprops.h. * modules/human (Files): Likewise. * modules/inttostr (Files): Likewise. * modules/sig2str (Files): Likewise. * modules/userspec (Files): Likewise. * modules/utimecmp (Files): Likewise. * modules/xnanosleep (Files): Likewise. * modules/xstrtol (Files): Likewise.
author Paul Eggert <eggert@cs.ucla.edu>
date Wed, 09 Mar 2005 19:11:23 +0000
parents
children 11672ccd9cf8
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/* intprops.h -- properties of integer types

   Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* Written by Paul Eggert.  */

#include <limits.h>

/* 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 integer type T use twos complement
   representation.  */
#define TYPE_TWOS_COMPLEMENT(t) ((t) - (t) 1 == (t) ((t) ~ (t) 1 + (t) 1))

/* True if the arithmetic type T is signed.  */
#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))

/* The maximum and minimum values for the integer type T.  These
   macros have undefined behavior if T is signed and has padding bits
   (i.e., bits that do not contribute to the value), or if T uses
   signed-magnitude representation.  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 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))

/* Bound on length of the string representing an integer value or type T.
   Subtract 1 for the sign bit if t is signed; log10 (2.0) < 146/485;
   add 1 for integer division truncation; add 1 more for a minus sign
   if needed.  */
#define INT_STRLEN_BOUND(t) \
  ((sizeof (t) * CHAR_BIT - 1) * 146 / 485 + 2)

/* Bound on buffer size needed to represent an integer value or type T,
   including the terminating null.  */
#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)