1 # Allow the builder to specify an external ZLIB rather than the version 2 # distributed with CVS. 3 4 # Copyright (c) 2003 5 # Anthon Pang <apang (a] telux.net>, 6 # Derek R. Price, Ximbiot <http://ximbiot.com>, 7 # and the Free Software Foundation, Inc. 8 9 # This program is free software; you can redistribute it and/or modify 10 # it under the terms of the GNU General Public License as published by 11 # the Free Software Foundation; either version 2, or (at your option) 12 # any later version. 13 14 # This program is distributed in the hope that it will be useful, 15 # but WITHOUT ANY WARRANTY; without even the implied warranty of 16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 # GNU General Public License for more details. 18 19 # You should have received a copy of the GNU General Public License 20 # along with this program; if not, write to the Free Software 21 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 22 # 02111-1307, USA. 23 24 # ACX_WITH_EXTERNAL_ZLIB 25 # ------------------- 26 # Determine which ZLIB to use. 27 AC_DEFUN([ACX_WITH_EXTERNAL_ZLIB],[ 28 # 29 # Use --with-zlib to build with a zlib other than the version distributed 30 # with CVS. 31 # 32 # defaults to the included snapshot of zlib 33 # 34 AC_ARG_WITH([external-zlib], 35 AC_HELP_STRING([--with-external-zlib], 36 [Use the specified ZLIB library (defaults to 37 the version distributed with the CVS source)]), 38 [with_external_zlib=$withval], 39 [with_external_zlib=no]) 40 41 # 42 # Try to locate a ZLIB installation if no location was specified, assuming 43 # external ZLIB was enabled. 44 # 45 if test -n "$acx_zlib_cv_external_zlib"; then 46 # Granted, this is a slightly ugly way to print this info, but the 47 # AC_CHECK_HEADER used in the search for a ZLIB installation makes using 48 # AC_CACHE_CHECK worse 49 AC_MSG_CHECKING([for external ZLIB]) 50 else :; fi 51 AC_CACHE_VAL([acx_zlib_cv_external_zlib], [ 52 # 53 # --with but no location specified 54 # assume zlib.h locates our install. 55 # 56 acx_zlib_save_CPPFLAGS=$CPPFLAGS 57 for acx_zlib_cv_external_zlib in yes /usr/local no; do 58 if test x$acx_zlib_cv_external_zlib = xno; then 59 break 60 fi 61 if test x$acx_zlib_cv_external_zlib = xyes; then 62 AC_MSG_CHECKING([for external ZLIB]) 63 AC_MSG_RESULT([]) 64 else 65 CPPFLAGS="$acx_zlib_save_CPPFLAGS -I$acx_zlib_cv_external_zlib/include" 66 AC_MSG_CHECKING([for external ZLIB in $acx_zlib_cv_external_zlib]) 67 AC_MSG_RESULT([]) 68 fi 69 unset ac_cv_header_zlib_h 70 AC_CHECK_HEADERS([zlib.h]) 71 if test "$ac_cv_header_zlib_h" = yes; then 72 break 73 fi 74 done 75 CPPFLAGS=$acx_zlib_save_CPPFLAGS 76 AC_MSG_CHECKING([for external ZLIB]) 77 ])dnl 78 AC_MSG_RESULT([$acx_zlib_cv_external_zlib]) 79 80 81 # 82 # Output a pretty message naming our selected ZLIB "external" or "package" 83 # so that any warnings printed by the version check make more sense. 84 # 85 AC_MSG_CHECKING([selected ZLIB]) 86 if test "x$with_external_zlib" = xno; then 87 AC_MSG_RESULT([package]) 88 else 89 AC_MSG_RESULT([external]) 90 fi 91 92 93 # 94 # Verify that the ZLIB we aren't using isn't newer than the one we are. 95 # 96 if test "x$acx_zlib_cv_external_zlib" != xno; then 97 LOCAL_ZLIB_VERSION=`sed -n '/^#define ZLIB_VERSION ".*"$/{ 98 s/^#define ZLIB_VERSION "\(.*\)"$/\1/; 99 p;}' <$srcdir/zlib/zlib.h 2>&AS_MESSAGE_LOG_FD` 100 ACX_EXTRACT_HEADER_DEFN([ZLIB_VERSION], [zlib.h]) 101 ZLIB_VERSION=`echo "$ZLIB_VERSION" |sed 's/"//g'` 102 ASX_VERSION_COMPARE([$LOCAL_ZLIB_VERSION], [$ZLIB_VERSION], 103 [if test "x$with_external_zlib" = xno; then 104 AC_MSG_WARN( 105 [Found external ZLIB with a more recent version than the 106 package version ($ZLIB_VERSION > $LOCAL_ZLIB_VERSION). configure with the 107 --with-external-zlib option to select the more recent version.]) 108 fi], 109 [], 110 [if test "x$with_external_zlib" != xno; then 111 AC_MSG_WARN( 112 [Package ZLIB is more recent than requested external version 113 ($LOCAL_ZLIB_VERSION > $ZLIB_VERSION). configure with the --without-external-zlib 114 option to select the more recent version.]) 115 fi]) 116 fi 117 118 119 # Now set with_external_zlib to our discovered value or the user specified 120 # value, as appropriate. 121 if test x$with_external_zlib = xyes; then 122 with_external_zlib=$acx_zlib_cv_external_zlib 123 fi 124 # $with_external_zlib could still be "no" 125 126 127 # 128 # Set up ZLIB includes for later use. 129 # 130 if test x$with_external_zlib != xyes \ 131 && test x$with_external_zlib != no; then 132 if test -z "$CPPFLAGS"; then 133 CPPFLAGS="-I$with_external_zlib/include" 134 else 135 CPPFLAGS="$CPPFLAGS -I$with_external_zlib/include" 136 fi 137 if test -z "$LDFLAGS"; then 138 LDFLAGS="-L$with_external_zlib/lib" 139 else 140 LDFLAGS="$LDFLAGS -L$with_external_zlib/lib" 141 fi 142 fi 143 144 ZLIB_CPPFLAGS= 145 ZLIB_LIBS= 146 ZLIB_SUBDIRS= 147 if test x$with_external_zlib = xno; then 148 # We need ZLIB_CPPFLAGS so that later executions of cpp from configure 149 # don't try to interpret $(top_srcdir) 150 ZLIB_CPPFLAGS='-I$(top_srcdir)/zlib' 151 ZLIB_LIBS='$(top_builddir)/zlib/libz.a' 152 # ZLIB_SUBDIRS is only used in the top level Makefiles. 153 ZLIB_SUBDIRS=zlib 154 else 155 # We know what to do now, so set up the CPPFLAGS, LDFLAGS, and LIBS for later 156 # use. 157 if test -z "$LIBS"; then 158 LIBS=-lz 159 else 160 LIBS="$LIBS -lz" 161 fi 162 163 # 164 # Verify external installed zlib works 165 # 166 # Ideally, we would also check that the version is newer 167 # 168 AC_MSG_CHECKING([that ZLIB library works]) 169 AC_TRY_LINK([#include <zlib.h>], 170 [int i = Z_OK; const char *version = zlibVersion();], 171 [AC_MSG_RESULT([yes])], 172 [AC_MSG_RESULT([no]) 173 AC_MSG_ERROR([ZLIB failed to link])]) 174 fi 175 176 dnl Subst for the local case 177 AC_SUBST(ZLIB_SUBDIRS)dnl 178 AC_SUBST(ZLIB_CPPFLAGS)dnl 179 AC_SUBST(ZLIB_LIBS)dnl 180 ]) 181
Indexes created Sun Apr 19 00:22:55 UTC 2026