# strerror.m4 serial 9

dnl Copyright (C) 2002, 2007-2010 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.

AC_DEFUN([gl_FUNC_STRERROR],

[

AC_REQUIRE([gl_FUNC_STRERROR_SEPARATE])

if test $REPLACE_STRERROR = 1; then

AC_LIBOBJ([strerror])

AC_DEFINE_UNQUOTED([REPLACE_STRERROR], [$REPLACE_STRERROR],

[Define this to 1 if strerror is broken.])

fi

])

# Like gl_FUNC_STRERROR, except prepare for separate compilation (no AC_LIBOBJ).

AC_DEFUN([gl_FUNC_STRERROR_SEPARATE],

[

AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])

AC_REQUIRE([gl_HEADER_ERRNO_H])

if test -z "$ERRNO_H"; then

AC_CACHE_CHECK([for working strerror function],

[gl_cv_func_working_strerror],

[AC_RUN_IFELSE(

[AC_LANG_PROGRAM(

[[#include <string.h>

]],

[[return !*strerror (-2);]])],

[gl_cv_func_working_strerror=yes],

[gl_cv_func_working_strerror=no],

[dnl Assume crossbuild works if it compiles.

AC_COMPILE_IFELSE(

[AC_LANG_PROGRAM(

[[#include <string.h>

]],

[[return !*strerror (-2);]])],

[gl_cv_func_working_strerror=yes],

[gl_cv_func_working_strerror=no])

])

])

if test $gl_cv_func_working_strerror = no; then

dnl The system's strerror() fails to return a string for out-of-range

dnl integers. Replace it.

REPLACE_STRERROR=1

fi

else

dnl The system's strerror() cannot know about the new errno values we add

dnl to <errno.h>. Replace it.

REPLACE_STRERROR=1

fi

if test $REPLACE_STRERROR = 1; then

gl_PREREQ_STRERROR

fi

])

# Prerequisites of lib/strerror.c.

AC_DEFUN([gl_PREREQ_STRERROR], [

AC_CHECK_DECLS([strerror])

AC_CHECK_HEADERS_ONCE([sys/socket.h])

if test $ac_cv_header_sys_socket_h != yes; then

dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make

dnl the check for those headers unconditional; yet cygwin reports

dnl that the headers are present but cannot be compiled (since on

dnl cygwin, all socket information should come from sys/socket.h).

AC_CHECK_HEADERS([winsock2.h])

fi

])