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- # ===========================================================================
- # https://www.gnu.org/software/autoconf-archive/ax_define_integer_bits.html
- # ===========================================================================
- #
- # SYNOPSIS
- #
- # AX_DEFINE_INTEGER_BITS (TYPE [, CANDIDATE-TYPE]...)
- #
- # DESCRIPTION
- #
- # Given a TYPE of the form "int##_t" or "uint##_t", see if the datatype
- # TYPE is predefined. If not, then define TYPE -- both with AC_DEFINE and
- # as a shell variable -- to the first datatype of exactly ## bits in a
- # list of CANDIDATE-TYPEs. If none of the CANDIDATE-TYPEs contains exactly
- # ## bits, then set the TYPE shell variable to "no".
- #
- # For example, the following ensures that uint64_t is defined as a 64-bit
- # datatype:
- #
- # AX_DEFINE_INTEGER_BITS(uint64_t, unsigned long long, unsigned __int64, long)
- # if test "$uint64_t" = no; then
- # AC_MSG_ERROR([unable to continue without a 64-bit datatype])
- # fi
- #
- # You should then put the following in your C code to ensure that all
- # datatypes defined by AX_DEFINE_INTEGER_BITS are visible to your program:
- #
- # #include "config.h"
- #
- # #if HAVE_INTTYPES_H
- # # include <inttypes.h>
- # #else
- # # if HAVE_STDINT_H
- # # include <stdint.h>
- # # endif
- # #endif
- #
- # LICENSE
- #
- # Copyright (c) 2008 Scott Pakin <pakin@uiuc.edu>
- #
- # Copying and distribution of this file, with or without modification, are
- # permitted in any medium without royalty provided the copyright notice
- # and this notice are preserved. This file is offered as-is, without any
- # warranty.
-
- #serial 7
-
- AU_ALIAS([AC_DEFINE_INTEGER_BITS], [AX_DEFINE_INTEGER_BITS])
- AC_DEFUN([AX_DEFINE_INTEGER_BITS],
- [m4_define([ac_datatype_bits], [m4_translit($1, [a-zA-Z_])])
- m4_define([ac_datatype_bytes], [m4_eval(ac_datatype_bits/8)])
- AC_CHECK_TYPE($1, ,
- [
- AC_MSG_NOTICE([trying to find a suitable ]ac_datatype_bytes[-byte replacement for $1])
- $1=no
- find_$1 ()
- {
- _AX_DEFINE_INTEGER_BITS_HELPER($@)
- :
- }
- find_$1
- AC_DEFINE_UNQUOTED($1, $$1,
- [If not already defined, then define as a datatype of *exactly* ]ac_datatype_bits[ bits.])
- ])
- ])
-
- dnl Iterate over arguments $2..$N, trying to find a good match for $1.
- m4_define([_AX_DEFINE_INTEGER_BITS_HELPER],
- [ifelse($2, , ,
- [m4_define([ac_datatype_bits], [m4_translit($1, [a-zA-Z_])])
- m4_define([ac_datatype_bytes], [m4_eval(ac_datatype_bits/8)])
- AC_CHECK_SIZEOF($2)
- if test "$AS_TR_SH(ac_cv_sizeof_$2)" -eq ac_datatype_bytes; then
- $1="$2"
- return
- fi
- _AX_DEFINE_INTEGER_BITS_HELPER($1, m4_shift(m4_shift($@)))
- ])
- ])
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