1# errno_h.m4 serial 6
2dnl Copyright (C) 2004, 2006, 2008, 2009 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7AC_DEFUN_ONCE([gl_HEADER_ERRNO_H],
8[
9  AC_REQUIRE([AC_PROG_CC])
10  AC_CACHE_CHECK([for complete errno.h], [gl_cv_header_errno_h_complete], [
11    AC_EGREP_CPP([booboo],[
12#include <errno.h>
13#if !defined ENOMSG
14booboo
15#endif
16#if !defined EIDRM
17booboo
18#endif
19#if !defined ENOLINK
20booboo
21#endif
22#if !defined EPROTO
23booboo
24#endif
25#if !defined EMULTIHOP
26booboo
27#endif
28#if !defined EBADMSG
29booboo
30#endif
31#if !defined EOVERFLOW
32booboo
33#endif
34#if !defined ENOTSUP
35booboo
36#endif
37#if !defined ESTALE
38booboo
39#endif
40#if !defined ECANCELED
41booboo
42#endif
43      ],
44      [gl_cv_header_errno_h_complete=no],
45      [gl_cv_header_errno_h_complete=yes])
46  ])
47  if test $gl_cv_header_errno_h_complete = yes; then
48    ERRNO_H=''
49  else
50    gl_CHECK_NEXT_HEADERS([errno.h])
51    ERRNO_H='errno.h'
52  fi
53  AC_SUBST([ERRNO_H])
54  gl_REPLACE_ERRNO_VALUE([EMULTIHOP])
55  gl_REPLACE_ERRNO_VALUE([ENOLINK])
56  gl_REPLACE_ERRNO_VALUE([EOVERFLOW])
57])
58
59# Assuming $1 = EOVERFLOW.
60# The EOVERFLOW errno value ought to be defined in <errno.h>, according to
61# POSIX.  But some systems (like OpenBSD 4.0 or AIX 3) don't define it, and
62# some systems (like OSF/1) define it when _XOPEN_SOURCE_EXTENDED is defined.
63# Check for the value of EOVERFLOW.
64# Set the variables EOVERFLOW_HIDDEN and EOVERFLOW_VALUE.
65AC_DEFUN([gl_REPLACE_ERRNO_VALUE],
66[
67  if test -n "$ERRNO_H"; then
68    AC_CACHE_CHECK([for ]$1[ value], [gl_cv_header_errno_h_]$1, [
69      AC_EGREP_CPP([yes],[
70#include <errno.h>
71#ifdef ]$1[
72yes
73#endif
74      ],
75      [gl_cv_header_errno_h_]$1[=yes],
76      [gl_cv_header_errno_h_]$1[=no])
77      if test $gl_cv_header_errno_h_]$1[ = no; then
78        AC_EGREP_CPP([yes],[
79#define _XOPEN_SOURCE_EXTENDED 1
80#include <errno.h>
81#ifdef ]$1[
82yes
83#endif
84          ], [gl_cv_header_errno_h_]$1[=hidden])
85        if test $gl_cv_header_errno_h_]$1[ = hidden; then
86          dnl The macro exists but is hidden.
87          dnl Define it to the same value.
88          AC_COMPUTE_INT([gl_cv_header_errno_h_]$1, $1, [
89#define _XOPEN_SOURCE_EXTENDED 1
90#include <errno.h>
91/* The following two lines are a workaround against an autoconf-2.52 bug.  */
92#include <stdio.h>
93#include <stdlib.h>
94])
95        fi
96      fi
97    ])
98    case $gl_cv_header_errno_h_]$1[ in
99      yes | no)
100        ]$1[_HIDDEN=0; ]$1[_VALUE=
101        ;;
102      *)
103        ]$1[_HIDDEN=1; ]$1[_VALUE="$gl_cv_header_errno_h_]$1["
104        ;;
105    esac
106    AC_SUBST($1[_HIDDEN])
107    AC_SUBST($1[_VALUE])
108  fi
109])
110
111dnl Autoconf >= 2.61 has AC_COMPUTE_INT built-in.
112dnl Remove this when we can assume autoconf >= 2.61.
113m4_ifdef([AC_COMPUTE_INT], [], [
114  AC_DEFUN([AC_COMPUTE_INT], [_AC_COMPUTE_INT([$2],[$1],[$3],[$4])])
115])
116