2N/A/* intprops.h -- properties of integer types
2N/A
2N/A Copyright (C) 2001, 2002, 2003, 2004, 2005, 2009, 2010 Free Software
2N/A Foundation, Inc.
2N/A
2N/A This program is free software: you can redistribute it and/or modify
2N/A it under the terms of the GNU General Public License as published by
2N/A the Free Software Foundation; either version 3 of the License, or
2N/A (at your option) any later version.
2N/A
2N/A This program is distributed in the hope that it will be useful,
2N/A but WITHOUT ANY WARRANTY; without even the implied warranty of
2N/A MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2N/A GNU General Public License for more details.
2N/A
2N/A You should have received a copy of the GNU General Public License
2N/A along with this program. If not, see <http://www.gnu.org/licenses/>. */
2N/A
2N/A/* Written by Paul Eggert. */
2N/A
2N/A#ifndef GL_INTPROPS_H
2N/A# define GL_INTPROPS_H
2N/A
2N/A# include <limits.h>
2N/A
2N/A/* The extra casts in the following macros work around compiler bugs,
2N/A e.g., in Cray C 5.0.3.0. */
2N/A
2N/A/* True if the arithmetic type T is an integer type. bool counts as
2N/A an integer. */
2N/A# define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
2N/A
2N/A/* True if negative values of the signed integer type T use two's
2N/A complement, ones' complement, or signed magnitude representation,
2N/A respectively. Much GNU code assumes two's complement, but some
2N/A people like to be portable to all possible C hosts. */
2N/A# define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
2N/A# define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
2N/A# define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
2N/A
2N/A/* True if the arithmetic type T is signed. */
2N/A# define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
2N/A
2N/A/* The maximum and minimum values for the integer type T. These
2N/A macros have undefined behavior if T is signed and has padding bits.
2N/A If this is a problem for you, please let us know how to fix it for
2N/A your host. */
2N/A# define TYPE_MINIMUM(t) \
2N/A ((t) (! TYPE_SIGNED (t) \
2N/A ? (t) 0 \
2N/A : TYPE_SIGNED_MAGNITUDE (t) \
2N/A ? ~ (t) 0 \
2N/A : ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
2N/A# define TYPE_MAXIMUM(t) \
2N/A ((t) (! TYPE_SIGNED (t) \
2N/A ? (t) -1 \
2N/A : ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))
2N/A
2N/A/* Return zero if T can be determined to be an unsigned type.
2N/A Otherwise, return 1.
2N/A When compiling with GCC, INT_STRLEN_BOUND uses this macro to obtain a
2N/A tighter bound. Otherwise, it overestimates the true bound by one byte
2N/A when applied to unsigned types of size 2, 4, 16, ... bytes.
2N/A The symbol signed_type_or_expr__ is private to this header file. */
2N/A# if __GNUC__ >= 2
2N/A# define signed_type_or_expr__(t) TYPE_SIGNED (__typeof__ (t))
2N/A# else
2N/A# define signed_type_or_expr__(t) 1
2N/A# endif
2N/A
2N/A/* Bound on length of the string representing an integer type or expression T.
2N/A Subtract 1 for the sign bit if T is signed; log10 (2.0) < 146/485;
2N/A add 1 for integer division truncation; add 1 more for a minus sign
2N/A if needed. */
2N/A# define INT_STRLEN_BOUND(t) \
2N/A ((sizeof (t) * CHAR_BIT - signed_type_or_expr__ (t)) * 146 / 485 \
2N/A + signed_type_or_expr__ (t) + 1)
2N/A
2N/A/* Bound on buffer size needed to represent an integer type or expression T,
2N/A including the terminating null. */
2N/A# define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
2N/A
2N/A#endif /* GL_INTPROPS_H */