# Allow the builder to specify an external ZLIB rather than the version
# distributed with CVS.
# Copyright (c) 2003
# Anthon Pang <apang@telux.net>,
# Derek R. Price, Ximbiot <http://ximbiot.com>,
# and the Free Software Foundation, Inc.
# 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, 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.
# ACX_WITH_EXTERNAL_ZLIB
# -------------------
# Determine which ZLIB to use.
AC_DEFUN([ACX_WITH_EXTERNAL_ZLIB],[
#
# Use --with-zlib to build with a zlib other than the version distributed
# with CVS.
#
# defaults to the included snapshot of zlib
#
AC_ARG_WITH([external-zlib],
AC_HELP_STRING([--with-external-zlib],
[Use the specified ZLIB library (defaults to
the version distributed with the CVS source)]),
[with_external_zlib=$withval],
[with_external_zlib=no])
#
# Try to locate a ZLIB installation if no location was specified, assuming
# external ZLIB was enabled.
#
if test -n "$acx_zlib_cv_external_zlib"; then
# Granted, this is a slightly ugly way to print this info, but the
# AC_CHECK_HEADER used in the search for a ZLIB installation makes using
# AC_CACHE_CHECK worse
AC_MSG_CHECKING([for external ZLIB])
else :; fi
AC_CACHE_VAL([acx_zlib_cv_external_zlib], [
#
# --with but no location specified
# assume zlib.h locates our install.
#
acx_zlib_save_CPPFLAGS=$CPPFLAGS
for acx_zlib_cv_external_zlib in yes /usr/local no; do
if test x$acx_zlib_cv_external_zlib = xno; then
break
fi
if test x$acx_zlib_cv_external_zlib = xyes; then
AC_MSG_CHECKING([for external ZLIB])
AC_MSG_RESULT([])
else
CPPFLAGS="$acx_zlib_save_CPPFLAGS -I$acx_zlib_cv_external_zlib/include"
AC_MSG_CHECKING([for external ZLIB in $acx_zlib_cv_external_zlib])
AC_MSG_RESULT([])
fi
unset ac_cv_header_zlib_h
AC_CHECK_HEADERS([zlib.h])
if test "$ac_cv_header_zlib_h" = yes; then
break
fi
done
CPPFLAGS=$acx_zlib_save_CPPFLAGS
AC_MSG_CHECKING([for external ZLIB])
])dnl
AC_MSG_RESULT([$acx_zlib_cv_external_zlib])
#
# Output a pretty message naming our selected ZLIB "external" or "package"
# so that any warnings printed by the version check make more sense.
#
AC_MSG_CHECKING([selected ZLIB])
if test "x$with_external_zlib" = xno; then
AC_MSG_RESULT([package])
else
AC_MSG_RESULT([external])
fi
#
# Verify that the ZLIB we aren't using isn't newer than the one we are.
#
if test "x$acx_zlib_cv_external_zlib" != xno; then
LOCAL_ZLIB_VERSION=`sed -n '/^#define ZLIB_VERSION ".*"$/{
s/^#define ZLIB_VERSION "\(.*\)"$/\1/;
p;}' <$srcdir/zlib/zlib.h 2>&AS_MESSAGE_LOG_FD`
ACX_EXTRACT_HEADER_DEFN([ZLIB_VERSION], [zlib.h])
ZLIB_VERSION=`echo "$ZLIB_VERSION" |sed 's/"//g'`
ASX_VERSION_COMPARE([$LOCAL_ZLIB_VERSION], [$ZLIB_VERSION],
[if test "x$with_external_zlib" = xno; then
AC_MSG_WARN(
[Found external ZLIB with a more recent version than the
package version ($ZLIB_VERSION > $LOCAL_ZLIB_VERSION). configure with the
--with-external-zlib option to select the more recent version.])
fi],
[],
[if test "x$with_external_zlib" != xno; then
AC_MSG_WARN(
[Package ZLIB is more recent than requested external version
($LOCAL_ZLIB_VERSION > $ZLIB_VERSION). configure with the --without-external-zlib
option to select the more recent version.])
fi])
fi
# Now set with_external_zlib to our discovered value or the user specified
# value, as appropriate.
if test x$with_external_zlib = xyes; then
with_external_zlib=$acx_zlib_cv_external_zlib
fi
# $with_external_zlib could still be "no"
#
# Set up ZLIB includes for later use.
#
if test x$with_external_zlib != xyes \
&& test x$with_external_zlib != no; then
if test -z "$CPPFLAGS"; then
CPPFLAGS="-I$with_external_zlib/include"
else
CPPFLAGS="$CPPFLAGS -I$with_external_zlib/include"
fi
if test -z "$LDFLAGS"; then
LDFLAGS="-L$with_external_zlib/lib"
else
LDFLAGS="$LDFLAGS -L$with_external_zlib/lib"
fi
fi
ZLIB_CPPFLAGS=
ZLIB_LIBS=
ZLIB_SUBDIRS=
if test x$with_external_zlib = xno; then
# We need ZLIB_CPPFLAGS so that later executions of cpp from configure
# don't try to interpret $(top_srcdir)
ZLIB_CPPFLAGS='-I$(top_srcdir)/zlib'
ZLIB_LIBS='$(top_builddir)/zlib/libz.a'
# ZLIB_SUBDIRS is only used in the top level Makefiles.
ZLIB_SUBDIRS=zlib
else
# We know what to do now, so set up the CPPFLAGS, LDFLAGS, and LIBS for later
# use.
if test -z "$LIBS"; then
LIBS=-lz
else
LIBS="$LIBS -lz"
fi
#
# Verify external installed zlib works
#
# Ideally, we would also check that the version is newer
#
AC_MSG_CHECKING([that ZLIB library works])
AC_TRY_LINK([#include <zlib.h>],
[int i = Z_OK; const char *version = zlibVersion();],
[AC_MSG_RESULT([yes])],
[AC_MSG_RESULT([no])
AC_MSG_ERROR([ZLIB failed to link])])
fi
dnl Subst for the local case
AC_SUBST(ZLIB_SUBDIRS)dnl
AC_SUBST(ZLIB_CPPFLAGS)dnl
AC_SUBST(ZLIB_LIBS)dnl
])