-# gethostname.m4 serial 6
-dnl Copyright (C) 2002, 2008, 2009 Free Software Foundation, Inc.
+# gethostname.m4 serial 9
+dnl Copyright (C) 2002, 2008, 2009, 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.
+# Ensure
+# - the gethostname() function,
+# - the HOST_NAME_MAX macro in <limits.h>.
AC_DEFUN([gl_FUNC_GETHOSTNAME],
[
AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
[gl_cv_w32_gethostname=no
gl_save_LIBS="$LIBS"
LIBS="$LIBS -lws2_32"
- AC_TRY_LINK([
+ AC_LINK_IFELSE([AC_LANG_PROGRAM([[
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#endif
#include <stddef.h>
-], [gethostname(NULL, 0);], [gl_cv_w32_gethostname=yes])
+]], [[gethostname(NULL, 0);]])], [gl_cv_w32_gethostname=yes])
LIBS="$gl_save_LIBS"
])
if test "$gl_cv_w32_gethostname" = "yes"; then
HAVE_GETHOSTNAME=0
gl_PREREQ_GETHOSTNAME
fi
+
+ dnl Also provide HOST_NAME_MAX when <limits.h> lacks it.
+ dnl - On most Unix systems, use MAXHOSTNAMELEN from <sys/param.h> instead.
+ dnl - On Solaris, Cygwin, BeOS, use MAXHOSTNAMELEN from <netdb.h> instead.
+ dnl - On mingw, use 256, because
+ dnl <http://msdn.microsoft.com/en-us/library/ms738527.aspx> says:
+ dnl "if a buffer of 256 bytes is passed in the name parameter and
+ dnl the namelen parameter is set to 256, the buffer size will always
+ dnl be adequate."
+ dnl With this, there is no need to use sysconf (_SC_HOST_NAME_MAX), which
+ dnl is not a compile-time constant.
+ dnl We cannot override <limits.h> using the usual technique, because
+ dnl gl_CHECK_NEXT_HEADERS does not work for <limits.h>. Therefore retrieve
+ dnl the value of HOST_NAME_MAX at configure time.
+ AC_CHECK_HEADERS_ONCE([sys/param.h])
+ AC_CHECK_HEADERS_ONCE([sys/socket.h])
+ AC_CHECK_HEADERS_ONCE([netdb.h])
+ AC_CACHE_CHECK([for HOST_NAME_MAX], [gl_cv_decl_HOST_NAME_MAX], [
+ gl_cv_decl_HOST_NAME_MAX=
+ AC_EGREP_CPP([lucky], [
+#include <limits.h>
+#ifdef HOST_NAME_MAX
+lucky
+#endif
+ ], [gl_cv_decl_HOST_NAME_MAX=yes])
+ if test -z "$gl_cv_decl_HOST_NAME_MAX"; then
+ dnl It's not defined in <limits.h>. Substitute it.
+ if test "$gl_cv_w32_gethostname" = yes; then
+ dnl mingw.
+ gl_cv_decl_HOST_NAME_MAX=256
+ else
+ _AC_COMPUTE_INT([MAXHOSTNAMELEN], [gl_cv_decl_HOST_NAME_MAX], [
+#include <sys/types.h>
+#if HAVE_SYS_PARAM_H
+# include <sys/param.h>
+#endif
+#if HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif
+#if HAVE_NETDB_H
+# include <netdb.h>
+#endif
+])
+ fi
+ fi
+ ])
+ if test "$gl_cv_decl_HOST_NAME_MAX" != yes; then
+ AC_DEFINE_UNQUOTED([HOST_NAME_MAX], [$gl_cv_decl_HOST_NAME_MAX],
+ [Define HOST_NAME_MAX when <limits.h> does not define it.])
+ fi
])
# Prerequisites of lib/gethostname.c.