##### http://autoconf-archive.cryp.to/ac_check_docbook_xslt.html
#
# SYNOPSIS
#
#   AC_CHECK_DOCBOOK_XSLT([xslt-version])
#
# DESCRIPTION
#
#   Check for access to docbook stylesheets of a particular revision.
#   This macro can be used for multiple versions within the same
#   script.
#
#   Input:
#
#   $1 is the version of docbook to search for; default 'current'.
#
#   Output:
#
#   $HAVE_DOCBOOK_XSLT_VERS will be set to 'yes' or 'no' depending on
#   the results of the test, where VERS is $1, with '_' substituted for
#   '.' $HAVE_DOCBOOK_XSLT will also be set to the same value.
#
#   Example:
#
#    AC_CHECK_DOCBOOK_XSLT(1.72.0)
#    if test "x$HAVE_DOCBOOK_XSLT_1_72_0" = "xyes"; then
#    ...
#
# LAST MODIFICATION
#
#   2007-05-15
#
# COPYLEFT
#
#   Copyright (c) 2007 Zmanda Inc. <http://www.zmanda.com/>
#   Copyright (c) 2007 Dustin J. Mitchell <dustin@zmanda.com>
#
#   This program is free software; you can redistribute it and/or
#   modify it under the terms of the GNU General Public License as
#   published by the Free Software Foundation; either version 2 of the
#   License, or (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful, but
#   WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
#   General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
#   02111-1307, USA.
#
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#   owner gives unlimited permission to copy, distribute and modify the
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#   modified version as well.

AC_DEFUN([AC_CHECK_DOCBOOK_XSLT],
[
    AC_REQUIRE([AC_PROG_XSLTPROC])

    dnl define a temporary variable for the version, so this macro can be
    dnl used with multiple versions
    define([_VERS], $1)
    ifelse(_VERS, [], [define([_VERS], [current])])
    define([ac_cv_docbook_xslt_VERS], patsubst([ac_cv_docbook_xslt_]_VERS, [\.], [_]))
    define([HAVE_DOCBOOK_XSLT_VERS], patsubst([HAVE_DOCBOOK_XSLT_]_VERS, [\.], [_]))

    AC_CACHE_CHECK([for Docbook XSLT version ]_VERS, [ac_cv_docbook_xslt_VERS],
    [
	ac_cv_docbook_xslt_VERS=no
	if test -n "$XSLTPROC"; then
	    echo "Trying '$XSLTPROC $XSLTPROC_FLAGS http://docbook.sourceforge.net/release/xsl/_VERS/xhtml/docbook.xsl'" >&AS_MESSAGE_LOG_FD
	    $XSLTPROC $XSLTPROC_FLAGS http://docbook.sourceforge.net/release/xsl/_VERS/xhtml/docbook.xsl >&AS_MESSAGE_LOG_FD 2>&1

	    if test "$?" = 0; then
		ac_cv_docbook_xslt_VERS=yes
	    fi
	fi
    ])

    HAVE_DOCBOOK_XSLT_VERS="$ac_cv_docbook_xslt_VERS"
    HAVE_DOCBOOK_XSLT=HAVE_DOCBOOK_XSLT_VERS
    undefine([_VERS])
])