# ===========================================================================

#       http://www.gnu.org/software/autoconf-archive/ax_check_zlib.html

# ===========================================================================

#

# SYNOPSIS

#

#   AX_CHECK_ZLIB([action-if-found], [action-if-not-found])

#

# DESCRIPTION

#

#   This macro searches for an installed zlib library. If nothing was

#   specified when calling configure, it searches first in /usr/local and

#   then in /usr, /opt/local and /sw. If the --with-zlib=DIR is specified,

#   it will try to find it in DIR/include/zlib.h and DIR/lib/libz.a. If

#   --without-zlib is specified, the library is not searched at all.

#

#   If either the header file (zlib.h) or the library (libz) is not found,

#   shell commands 'action-if-not-found' is run. If 'action-if-not-found' is

#   not specified, the configuration exits on error, asking for a valid zlib

#   installation directory or --without-zlib.

#

#   If both header file and library are found, shell commands

#   'action-if-found' is run. If 'action-if-found' is not specified, the

#   default action appends '-I${ZLIB_HOME}/include' to CPFLAGS, appends

#   '-L$ZLIB_HOME}/lib' to LDFLAGS, prepends '-lz' to LIBS, and calls

#   AC_DEFINE(HAVE_LIBZ). You should use autoheader to include a definition

#   for this symbol in a config.h file. Sample usage in a C/C++ source is as

#   follows:

#

#     #ifdef HAVE_LIBZ

#     #include <zlib.h>

#     #endif /* HAVE_LIBZ */

#

# LICENSE

#

#   Copyright (c) 2008 Loic Dachary <loic@senga.org>

#   Copyright (c) 2010 Bastien Chevreux <bach@chevreux.org>

#

#   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, see <http://www.gnu.org/licenses/>.

#

#   As a special exception, the respective Autoconf Macro's copyright owner

#   gives unlimited permission to copy, distribute and modify the configure

#   scripts that are the output of Autoconf when processing the Macro. You

#   need not follow the terms of the GNU General Public License when using

#   or distributing such scripts, even though portions of the text of the

#   Macro appear in them. The GNU General Public License (GPL) does govern

#   all other use of the material that constitutes the Autoconf Macro.

#

#   This special exception to the GPL applies to versions of the Autoconf

#   Macro released by the Autoconf Archive. When you make and distribute a

#   modified version of the Autoconf Macro, you may extend this special

#   exception to the GPL to apply to your modified version as well.

#serial 14

AU_ALIAS([CHECK_ZLIB], [AX_CHECK_ZLIB])

AC_DEFUN([AX_CHECK_ZLIB],

#

# Handle user hints

#

[AC_MSG_CHECKING(if zlib is wanted)

zlib_places="/usr/local /usr /opt/local /sw"

AC_ARG_WITH([zlib],

[  --with-zlib=DIR         root directory path of zlib installation @<:@defaults to

                          /usr/local or /usr if not found in /usr/local@:>@

  --without-zlib          to disable zlib usage completely],

[if test "$withval" != no ; then

  AC_MSG_RESULT(yes)

  if test -d "$withval"

  then

    zlib_places="$withval $zlib_places"

  else

    AC_MSG_WARN([Sorry, $withval does not exist, checking usual places])

  fi

else

  zlib_places=

  AC_MSG_RESULT(no)

fi],

[AC_MSG_RESULT(yes)])

#

# Locate zlib, if wanted

#

if test -n "${zlib_places}"

then

	# check the user supplied or any other more or less 'standard' place:

	#   Most UNIX systems      : /usr/local and /usr

	#   MacPorts / Fink on OSX : /opt/local respectively /sw

	for ZLIB_HOME in ${zlib_places} ; do

	  if test -f "${ZLIB_HOME}/include/zlib.h"; then break; fi

	  ZLIB_HOME=""

	done

  ZLIB_OLD_LDFLAGS="$LDFLAGS"

  ZLIB_OLD_CPPFLAGS="$CPPFLAGS"

  if test -n "${ZLIB_HOME}"; then

        LDFLAGS="$LDFLAGS -L${ZLIB_HOME}/lib"

        CPPFLAGS="$CPPFLAGS -I${ZLIB_HOME}/include"

  fi

  AC_LANG_SAVE

  AC_LANG_C

  AC_CHECK_LIB([z], [inflateEnd], [zlib_cv_libz=yes], [zlib_cv_libz=no])

  AC_CHECK_HEADER([zlib.h], [zlib_cv_zlib_h=yes], [zlib_cv_zlib_h=no])

  AC_LANG_RESTORE

  if test "$zlib_cv_libz" = "yes" && test "$zlib_cv_zlib_h" = "yes"

  then

    #

    # If both library and header were found, action-if-found

    #

    m4_ifblank([$1],[

		test "$enable_rpath" = yes -a "$ZLIB_HOME" != /usr && \

		    LDFLAGS="$LDFLAGS -R${ZLIB_HOME}/lib"

                LIBS="-lz $LIBS"

                AC_DEFINE([HAVE_LIBZ], [1],

                          [Define to 1 if you have `z' library (-lz)])

               ],[

                # Restore variables

                LDFLAGS="$ZLIB_OLD_LDFLAGS"

                CPPFLAGS="$ZLIB_OLD_CPPFLAGS"

                $1

               ])

  else

    #

    # If either header or library was not found, action-if-not-found

    #

    m4_default([$2],[

                AC_MSG_ERROR([either specify a valid zlib installation with --with-zlib=DIR or disable zlib usage with --without-zlib])

                ])

  fi

fi

])