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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 05:31:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 05:31:45 +0000 |
commit | 74aa0bc6779af38018a03fd2cf4419fe85917904 (patch) | |
tree | 9cb0681aac9a94a49c153d5823e7a55d1513d91f /m4/size_max.m4 | |
parent | Initial commit. (diff) | |
download | sssd-74aa0bc6779af38018a03fd2cf4419fe85917904.tar.xz sssd-74aa0bc6779af38018a03fd2cf4419fe85917904.zip |
Adding upstream version 2.9.4.upstream/2.9.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'm4/size_max.m4')
-rw-r--r-- | m4/size_max.m4 | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/m4/size_max.m4 b/m4/size_max.m4 new file mode 100644 index 0000000..4fe81c7 --- /dev/null +++ b/m4/size_max.m4 @@ -0,0 +1,59 @@ +# size_max.m4 serial 2 +dnl Copyright (C) 2003 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +dnl From Bruno Haible. + +AC_DEFUN([gl_SIZE_MAX], +[ + AC_CHECK_HEADERS(stdint.h) + dnl First test whether the system already has SIZE_MAX. + AC_MSG_CHECKING([for SIZE_MAX]) + result= + AC_EGREP_CPP([Found it], [ +#include <limits.h> +#if HAVE_STDINT_H +#include <stdint.h> +#endif +#ifdef SIZE_MAX +Found it +#endif +], result=yes) + if test -z "$result"; then + dnl Define it ourselves. Here we assume that the type 'size_t' is not wider + dnl than the type 'unsigned long'. + dnl The _AC_COMPUTE_INT macro works up to LONG_MAX, since it uses 'expr', + dnl which is guaranteed to work from LONG_MIN to LONG_MAX. + _AC_COMPUTE_INT([~(size_t)0 / 10], res_hi, + [#include <stddef.h>], result=?) + _AC_COMPUTE_INT([~(size_t)0 % 10], res_lo, + [#include <stddef.h>], result=?) + _AC_COMPUTE_INT([sizeof (size_t) <= sizeof (unsigned int)], fits_in_uint, + [#include <stddef.h>], result=?) + if test "$fits_in_uint" = 1; then + dnl Even though SIZE_MAX fits in an unsigned int, it must be of type + dnl 'unsigned long' if the type 'size_t' is the same as 'unsigned long'. + AC_TRY_COMPILE([#include <stddef.h> + extern size_t foo; + extern unsigned long foo; + ], [], fits_in_uint=0) + fi + if test -z "$result"; then + if test "$fits_in_uint" = 1; then + result="$res_hi$res_lo"U + else + result="$res_hi$res_lo"UL + fi + else + dnl Shouldn't happen, but who knows... + result='~(size_t)0' + fi + fi + AC_MSG_RESULT([$result]) + if test "$result" != yes; then + AC_DEFINE_UNQUOTED([SIZE_MAX], [$result], + [Define as the maximum value of type 'size_t', if the system doesn't define it.]) + fi +]) |