2 dnl Copyright (C) 2004, 2006, 2008, 2009 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 dnl This macro must pass through AC_REQUIRE (never directly invoke it).
8 AC_DEFUN_ONCE([gl_HEADER_ERRNO_H],
10 AC_REQUIRE([AC_PROG_CC])
11 AC_CACHE_CHECK([for complete errno.h], [gl_cv_header_errno_h_complete], [
12 AC_EGREP_CPP([booboo],[
26 #if !defined EMULTIHOP
32 #if !defined EOVERFLOW
38 #if !defined ECANCELED
42 [gl_cv_header_errno_h_complete=no],
43 [gl_cv_header_errno_h_complete=yes])
45 if test $gl_cv_header_errno_h_complete = yes; then
48 gl_CHECK_NEXT_HEADERS([errno.h])
52 gl_REPLACE_ERRNO_VALUE([EMULTIHOP])
53 gl_REPLACE_ERRNO_VALUE([ENOLINK])
54 gl_REPLACE_ERRNO_VALUE([EOVERFLOW])
57 # Assuming $1 = EOVERFLOW.
58 # The EOVERFLOW errno value ought to be defined in <errno.h>, according to
59 # POSIX. But some systems (like OpenBSD 4.0 or AIX 3) don't define it, and
60 # some systems (like OSF/1) define it when _XOPEN_SOURCE_EXTENDED is defined.
61 # Check for the value of EOVERFLOW.
62 # Set the variables EOVERFLOW_HIDDEN and EOVERFLOW_VALUE.
63 AC_DEFUN([gl_REPLACE_ERRNO_VALUE],
65 if test -n "$ERRNO_H"; then
66 AC_CACHE_CHECK([for ]$1[ value], [gl_cv_header_errno_h_]$1, [
73 [gl_cv_header_errno_h_]$1[=yes],
74 [gl_cv_header_errno_h_]$1[=no])
75 if test $gl_cv_header_errno_h_]$1[ = no; then
77 #define _XOPEN_SOURCE_EXTENDED 1
82 ], [gl_cv_header_errno_h_]$1[=hidden])
83 if test $gl_cv_header_errno_h_]$1[ = hidden; then
84 dnl The macro exists but is hidden.
85 dnl Define it to the same value.
86 AC_COMPUTE_INT([gl_cv_header_errno_h_]$1, $1, [
87 #define _XOPEN_SOURCE_EXTENDED 1
89 /* The following two lines are a workaround against an autoconf-2.52 bug. */
96 case $gl_cv_header_errno_h_]$1[ in
98 ]$1[_HIDDEN=0; ]$1[_VALUE=
101 ]$1[_HIDDEN=1; ]$1[_VALUE="$gl_cv_header_errno_h_]$1["
104 AC_SUBST($1[_HIDDEN])
109 dnl Autoconf >= 2.61 has AC_COMPUTE_INT built-in.
110 dnl Remove this when we can assume autoconf >= 2.61.
111 m4_ifdef([AC_COMPUTE_INT], [], [
112 AC_DEFUN([AC_COMPUTE_INT], [_AC_COMPUTE_INT([$2],[$1],[$3],[$4])])