acinclude.m4

   1 # -*- autoconf -*-
   2
   3 # Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at:
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 dnl OVS_ENABLE_WERROR
  18 AC_DEFUN([OVS_ENABLE_WERROR],
  19   [AC_ARG_ENABLE(
  20      [Werror],
  21      [AC_HELP_STRING([--enable-Werror], [Add -Werror to CFLAGS])],
  22      [], [enable_Werror=no])
  23    AC_CONFIG_COMMANDS_PRE(
  24      [if test "X$enable_Werror" = Xyes; then
  25         CFLAGS="$CFLAGS -Werror"
  26       fi])])
  27
  28 dnl OVS_CHECK_LINUX
  29 dnl
  30 dnl Configure linux kernel source tree
  31 AC_DEFUN([OVS_CHECK_LINUX], [
  32   AC_ARG_WITH([linux],
  33               [AC_HELP_STRING([--with-linux=/path/to/linux],
  34                               [Specify the Linux kernel build directory])])
  35   AC_ARG_WITH([linux-source],
  36               [AC_HELP_STRING([--with-linux-source=/path/to/linux-source],
  37                               [Specify the Linux kernel source directory
  38                                (usually figured out automatically from build
  39                                directory)])])
  40
  41   # Deprecated equivalents to --with-linux, --with-linux-source.
  42   AC_ARG_WITH([l26])
  43   AC_ARG_WITH([l26-source])
  44
  45   if test X"$with_linux" != X; then
  46     KBUILD=$with_linux
  47   elif test X"$with_l26" != X; then
  48     KBUILD=$with_l26
  49     AC_MSG_WARN([--with-l26 is deprecated, please use --with-linux instead])
  50   else
  51     KBUILD=
  52   fi
  53
  54   if test X"$KBUILD" != X; then
  55     if test X"$with_linux_source" != X; then
  56       KSRC=$with_linux_source
  57     elif test X"$with_l26_source" != X; then
  58       KSRC=$with_l26_source
  59       AC_MSG_WARN([--with-l26-source is deprecated, please use --with-linux-source instead])
  60     else
  61       KSRC=
  62     fi
  63   elif test X"$with_linux_source" != X || test X"$with_l26_source" != X; then
  64     AC_MSG_ERROR([Linux source directory may not be specified without Linux build directory])
  65   fi
  66
  67   if test -n "$KBUILD"; then
  68     KBUILD=`eval echo "$KBUILD"`
  69     case $KBUILD in
  70         /*) ;;
  71         *) KBUILD=`pwd`/$KBUILD ;;
  72     esac
  73
  74     # The build directory is what the user provided.
  75     # Make sure that it exists.
  76     AC_MSG_CHECKING([for Linux build directory])
  77     if test -d "$KBUILD"; then
  78         AC_MSG_RESULT([$KBUILD])
  79         AC_SUBST(KBUILD)
  80     else
  81         AC_MSG_RESULT([no])
  82         AC_ERROR([source dir $KBUILD doesn't exist])
  83     fi
  84
  85     # Debian breaks kernel headers into "source" header and "build" headers.
  86     # We want the source headers, but $KBUILD gives us the "build" headers.
  87     # Use heuristics to find the source headers.
  88     AC_MSG_CHECKING([for Linux source directory])
  89     if test -n "$KSRC"; then
  90       KSRC=`eval echo "$KSRC"`
  91       case $KSRC in
  92           /*) ;;
  93           *) KSRC=`pwd`/$KSRC ;;
  94       esac
  95       if test ! -e $KSRC/include/linux/kernel.h; then
  96         AC_MSG_ERROR([$KSRC is not a kernel source directory])
  97       fi
  98     else
  99       KSRC=$KBUILD
 100       if test ! -e $KSRC/include/linux/kernel.h; then
 101         # Debian kernel build Makefiles tend to include a line of the form:
 102         # MAKEARGS := -C /usr/src/linux-headers-3.2.0-1-common O=/usr/src/linux-headers-3.2.0-1-486
 103         # First try to extract the source directory from this line.
 104         KSRC=`sed -n 's/.*-C \([[^ ]]*\).*/\1/p' "$KBUILD"/Makefile`
 105         if test ! -e "$KSRC"/include/linux/kernel.h; then
 106           # Didn't work.  Fall back to name-based heuristics that used to work.
 107           case `echo "$KBUILD" | sed 's,/*$,,'` in # (
 108             */build)
 109               KSRC=`echo "$KBUILD" | sed 's,/build/*$,/source,'`
 110               ;; # (
 111             *)
 112               KSRC=`(cd $KBUILD && pwd -P) | sed 's,-[[^-]]*$,-common,'`
 113               ;;
 114           esac
 115         fi
 116       fi
 117       if test ! -e "$KSRC"/include/linux/kernel.h; then
 118         AC_MSG_ERROR([cannot find source directory (please use --with-linux-source)])
 119       fi
 120     fi
 121     AC_MSG_RESULT([$KSRC])
 122
 123     AC_MSG_CHECKING([for kernel version])
 124     version=`sed -n 's/^VERSION = //p' "$KSRC/Makefile"`
 125     patchlevel=`sed -n 's/^PATCHLEVEL = //p' "$KSRC/Makefile"`
 126     sublevel=`sed -n 's/^SUBLEVEL = //p' "$KSRC/Makefile"`
 127     if test X"$version" = X || test X"$patchlevel" = X; then
 128        AC_ERROR([cannot determine kernel version])
 129     elif test X"$sublevel" = X; then
 130        kversion=$version.$patchlevel
 131     else
 132        kversion=$version.$patchlevel.$sublevel
 133     fi
 134     AC_MSG_RESULT([$kversion])
 135
 136     if test "$version" -ge 3; then
 137        : # Linux 3.x
 138     elif test "$version" = 2 && test "$patchlevel" -ge 6; then
 139        : # Linux 2.6.x
 140     else
 141        if test "$KBUILD" = "$KSRC"; then
 142          AC_ERROR([Linux kernel in $KBUILD is version $kversion, but version 2.6 or later is required])
 143        else
 144          AC_ERROR([Linux kernel in build tree $KBUILD (source tree $KSRC) is version $kversion, but version 2.6 or later is required])
 145        fi
 146     fi
 147     if (test ! -e "$KBUILD"/include/linux/version.h && \
 148         test ! -e "$KBUILD"/include/generated/uapi/linux/version.h)|| \
 149        (test ! -e "$KBUILD"/include/linux/autoconf.h && \
 150         test ! -e "$KBUILD"/include/generated/autoconf.h); then
 151         AC_MSG_ERROR([Linux kernel source in $KBUILD is not configured])
 152     fi
 153     OVS_CHECK_LINUX_COMPAT
 154   fi
 155   AM_CONDITIONAL(LINUX_ENABLED, test -n "$KBUILD")
 156 ])
 157
 158 dnl OVS_GREP_IFELSE(FILE, REGEX, [IF-MATCH], [IF-NO-MATCH])
 159 dnl
 160 dnl Greps FILE for REGEX.  If it matches, runs IF-MATCH, otherwise IF-NO-MATCH.
 161 dnl If IF-MATCH is empty then it defines to OVS_DEFINE(HAVE_<REGEX>), with
 162 dnl <REGEX> translated to uppercase.
 163 AC_DEFUN([OVS_GREP_IFELSE], [
 164   AC_MSG_CHECKING([whether $2 matches in $1])
 165   if test -f $1; then
 166     grep '$2' $1 >/dev/null 2>&1
 167     status=$?
 168     case $status in
 169       0)
 170         AC_MSG_RESULT([yes])
 171         m4_if([$3], [], [OVS_DEFINE([HAVE_]m4_toupper([$2]))], [$3])
 172         ;;
 173       1)
 174         AC_MSG_RESULT([no])
 175         $4
 176         ;;
 177       *)
 178         AC_MSG_ERROR([grep exited with status $status])
 179         ;;
 180     esac
 181   else
 182     AC_MSG_RESULT([file not found])
 183     $4
 184   fi
 185 ])
 186
 187 dnl OVS_DEFINE(NAME)
 188 dnl
 189 dnl Defines NAME to 1 in kcompat.h.
 190 AC_DEFUN([OVS_DEFINE], [
 191   echo '#define $1 1' >> datapath/linux/kcompat.h.new
 192 ])
 193
 194 AC_DEFUN([OVS_CHECK_LOG2_H], [
 195   AC_MSG_CHECKING([for $KSRC/include/linux/log2.h])
 196   if test -e $KSRC/include/linux/log2.h; then
 197     AC_MSG_RESULT([yes])
 198     OVS_DEFINE([HAVE_LOG2_H])
 199   else
 200     AC_MSG_RESULT([no])
 201   fi
 202 ])
 203
 204 dnl OVS_CHECK_LINUX_COMPAT
 205 dnl
 206 dnl Runs various Autoconf checks on the Linux 2.6 kernel source in
 207 dnl the directory in $KBUILD.
 208 AC_DEFUN([OVS_CHECK_LINUX_COMPAT], [
 209   rm -f datapath/linux/kcompat.h.new
 210   mkdir -p datapath/linux
 211   : > datapath/linux/kcompat.h.new
 212
 213   OVS_GREP_IFELSE([$KSRC/arch/x86/include/asm/checksum_32.h], [src_err,],
 214                   [OVS_DEFINE([HAVE_CSUM_COPY_DBG])])
 215
 216   OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [ERR_CAST])
 217
 218   OVS_GREP_IFELSE([$KSRC/include/linux/etherdevice.h], [eth_hw_addr_random])
 219
 220   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_set_encap_proto])
 221
 222   OVS_GREP_IFELSE([$KSRC/include/linux/in.h], [ipv4_is_multicast])
 223
 224   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_disable_lro])
 225   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_stats])
 226   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_by_index_rcu])
 227   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [__skb_gso_segment])
 228   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [can_checksum_protocol])
 229
 230   OVS_GREP_IFELSE([$KSRC/include/linux/rcupdate.h], [rcu_read_lock_held], [],
 231                   [OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h],
 232                                    [rcu_read_lock_held])])
 233
 234   # Check for the proto_data_valid member in struct sk_buff.  The [^@]
 235   # is necessary because some versions of this header remove the
 236   # member but retain the kerneldoc comment that describes it (which
 237   # starts with @).  The brackets must be doubled because of m4
 238   # quoting rules.
 239   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [[[^@]]proto_data_valid],
 240                   [OVS_DEFINE([HAVE_PROTO_DATA_VALID])])
 241   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [raw],
 242                   [OVS_DEFINE([HAVE_MAC_RAW])])
 243   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_dst(],
 244                   [OVS_DEFINE([HAVE_SKB_DST_ACCESSOR_FUNCS])])
 245   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
 246                   [skb_copy_from_linear_data_offset])
 247   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
 248                   [skb_reset_tail_pointer])
 249   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_cow_head])
 250   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_transport_header],
 251                   [OVS_DEFINE([HAVE_SKBUFF_HEADER_HELPERS])])
 252   OVS_GREP_IFELSE([$KSRC/include/linux/icmpv6.h], [icmp6_hdr],
 253                   [OVS_DEFINE([HAVE_ICMP6_HDR])])
 254   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_warn_if_lro],
 255                   [OVS_DEFINE([HAVE_SKB_WARN_LRO])])
 256   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [consume_skb])
 257   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_frag_page])
 258   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_reset_mac_len])
 259   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_unclone])
 260
 261   OVS_GREP_IFELSE([$KSRC/include/linux/string.h], [kmemdup], [],
 262                   [OVS_GREP_IFELSE([$KSRC/include/linux/slab.h], [kmemdup])])
 263
 264   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [bool],
 265                   [OVS_DEFINE([HAVE_BOOL_TYPE])])
 266   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [__wsum],
 267                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
 268   OVS_GREP_IFELSE([$KSRC/include/uapi/linux/types.h], [__wsum],
 269                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
 270
 271   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_replace4])
 272   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_unfold])
 273
 274   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [NLA_NUL_STRING])
 275   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_get_be16])
 276   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be16])
 277   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be32])
 278   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be64])
 279   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_find_nested])
 280
 281   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [ADD_ALL_VLANS_CMD],
 282                   [OVS_DEFINE([HAVE_VLAN_BUG_WORKAROUND])])
 283
 284   OVS_GREP_IFELSE([$KSRC/include/linux/percpu.h], [this_cpu_ptr])
 285
 286   OVS_GREP_IFELSE([$KSRC/include/linux/openvswitch.h], [openvswitch_handle_frame_hook],
 287                   [OVS_DEFINE([HAVE_RHEL_OVS_HOOK])])
 288
 289   OVS_CHECK_LOG2_H
 290
 291   if cmp -s datapath/linux/kcompat.h.new \
 292             datapath/linux/kcompat.h >/dev/null 2>&1; then
 293     rm datapath/linux/kcompat.h.new
 294   else
 295     mv datapath/linux/kcompat.h.new datapath/linux/kcompat.h
 296   fi
 297 ])
 298
 299 dnl Checks for net/if_packet.h.
 300 AC_DEFUN([OVS_CHECK_IF_PACKET],
 301   [AC_CHECK_HEADER([net/if_packet.h],
 302                    [HAVE_IF_PACKET=yes],
 303                    [HAVE_IF_PACKET=no])
 304    AM_CONDITIONAL([HAVE_IF_PACKET], [test "$HAVE_IF_PACKET" = yes])
 305    if test "$HAVE_IF_PACKET" = yes; then
 306       AC_DEFINE([HAVE_IF_PACKET], [1],
 307                 [Define to 1 if net/if_packet.h is available.])
 308    fi])
 309
 310 dnl Checks for net/if_dl.h.
 311 dnl
 312 dnl (We use this as a proxy for checking whether we're building on FreeBSD
 313 dnl or NetBSD.)
 314 AC_DEFUN([OVS_CHECK_IF_DL],
 315   [AC_CHECK_HEADER([net/if_dl.h],
 316                    [HAVE_IF_DL=yes],
 317                    [HAVE_IF_DL=no])
 318    AM_CONDITIONAL([HAVE_IF_DL], [test "$HAVE_IF_DL" = yes])
 319    if test "$HAVE_IF_DL" = yes; then
 320       AC_DEFINE([HAVE_IF_DL], [1],
 321                 [Define to 1 if net/if_dl.h is available.])
 322
 323       # On these platforms we use libpcap to access network devices.
 324       AC_SEARCH_LIBS([pcap_open_live], [pcap])
 325    fi])
 326
 327 dnl Checks for buggy strtok_r.
 328 dnl
 329 dnl Some versions of glibc 2.7 has a bug in strtok_r when compiling
 330 dnl with optimization that can cause segfaults:
 331 dnl
 332 dnl http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
 333 AC_DEFUN([OVS_CHECK_STRTOK_R],
 334   [AC_CACHE_CHECK(
 335      [whether strtok_r macro segfaults on some inputs],
 336      [ovs_cv_strtok_r_bug],
 337      [AC_RUN_IFELSE(
 338         [AC_LANG_PROGRAM([#include <stdio.h>
 339                           #include <string.h>
 340                          ],
 341                          [[char string[] = ":::";
 342                            char *save_ptr = (char *) 0xc0ffee;
 343                            char *token1, *token2;
 344                            token1 = strtok_r(string, ":", &save_ptr);
 345                            token2 = strtok_r(NULL, ":", &save_ptr);
 346                            freopen ("/dev/null", "w", stdout);
 347                            printf ("%s %s\n", token1, token2);
 348                            return 0;
 349                           ]])],
 350         [ovs_cv_strtok_r_bug=no],
 351         [ovs_cv_strtok_r_bug=yes],
 352         [ovs_cv_strtok_r_bug=yes])])
 353    if test $ovs_cv_strtok_r_bug = yes; then
 354      AC_DEFINE([HAVE_STRTOK_R_BUG], [1],
 355                [Define if strtok_r macro segfaults on some inputs])
 356    fi
 357 ])
 358
 359 dnl ----------------------------------------------------------------------
 360 dnl These macros are from GNU PSPP, with the following original license:
 361 dnl Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
 362 dnl This file is free software; the Free Software Foundation
 363 dnl gives unlimited permission to copy and/or distribute it,
 364 dnl with or without modifications, as long as this notice is preserved.
 365
 366 AC_DEFUN([_OVS_CHECK_CC_OPTION], [dnl
 367   m4_define([ovs_cv_name], [ovs_cv_[]m4_translit([$1], [-], [_])])dnl
 368   AC_CACHE_CHECK([whether $CC accepts $1], [ovs_cv_name],
 369     [ovs_save_CFLAGS="$CFLAGS"
 370      dnl Include -Werror in the compiler options, because without -Werror
 371      dnl clang's GCC-compatible compiler driver does not return a failure
 372      dnl exit status even though it complains about options it does not
 373      dnl understand.
 374      CFLAGS="$CFLAGS $WERROR $1"
 375      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [ovs_cv_name[]=yes], [ovs_cv_name[]=no])
 376      CFLAGS="$ovs_save_CFLAGS"])
 377   if test $ovs_cv_name = yes; then
 378     m4_if([$2], [], [:], [$2])
 379   else
 380     m4_if([$3], [], [:], [$3])
 381   fi
 382 ])
 383
 384 dnl OVS_CHECK_WERROR
 385 dnl
 386 dnl Check whether the C compiler accepts -Werror.
 387 dnl Sets $WERROR to "-Werror", if so, and otherwise to the empty string.
 388 AC_DEFUN([OVS_CHECK_WERROR],
 389   [WERROR=
 390    _OVS_CHECK_CC_OPTION([-Werror], [WERROR=-Werror])])
 391
 392 dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
 393 dnl Check whether the given C compiler OPTION is accepted.
 394 dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
 395 AC_DEFUN([OVS_CHECK_CC_OPTION],
 396   [AC_REQUIRE([OVS_CHECK_WERROR])
 397    _OVS_CHECK_CC_OPTION([$1], [$2], [$3])])
 398
 399 dnl OVS_ENABLE_OPTION([OPTION])
 400 dnl Check whether the given C compiler OPTION is accepted.
 401 dnl If so, add it to WARNING_FLAGS.
 402 dnl Example: OVS_ENABLE_OPTION([-Wdeclaration-after-statement])
 403 AC_DEFUN([OVS_ENABLE_OPTION],
 404   [OVS_CHECK_CC_OPTION([$1], [WARNING_FLAGS="$WARNING_FLAGS $1"])
 405    AC_SUBST([WARNING_FLAGS])])
 406
 407 dnl OVS_CONDITIONAL_CC_OPTION([OPTION], [CONDITIONAL])
 408 dnl Check whether the given C compiler OPTION is accepted.
 409 dnl If so, enable the given Automake CONDITIONAL.
 410
 411 dnl Example: OVS_CONDITIONAL_CC_OPTION([-Wno-unused], [HAVE_WNO_UNUSED])
 412 AC_DEFUN([OVS_CONDITIONAL_CC_OPTION],
 413   [OVS_CHECK_CC_OPTION(
 414     [$1], [ovs_have_cc_option=yes], [ovs_have_cc_option=no])
 415    AM_CONDITIONAL([$2], [test $ovs_have_cc_option = yes])])
 416 dnl ----------------------------------------------------------------------
 417
 418 dnl Check for too-old XenServer.
 419 AC_DEFUN([OVS_CHECK_XENSERVER_VERSION],
 420   [AC_CACHE_CHECK([XenServer release], [ovs_cv_xsversion],
 421     [if test -e /etc/redhat-release; then
 422        ovs_cv_xsversion=`sed -n 's/^XenServer DDK release \([[^-]]*\)-.*/\1/p' /etc/redhat-release`
 423      fi
 424      if test -z "$ovs_cv_xsversion"; then
 425        ovs_cv_xsversion=none
 426      fi])
 427   case $ovs_cv_xsversion in
 428     none)
 429       ;;
 430
 431     [[1-9]][[0-9]]* |                    dnl XenServer 10 or later
 432     [[6-9]]* |                           dnl XenServer 6 or later
 433     5.[[7-9]]* |                         dnl XenServer 5.7 or later
 434     5.6.[[1-9]][[0-9]][[0-9]][[0-9]]* |  dnl XenServer 5.6.1000 or later
 435     5.6.[[2-9]][[0-9]][[0-9]]* |         dnl XenServer 5.6.200 or later
 436     5.6.1[[0-9]][[0-9]])                 dnl Xenserver 5.6.100 or later
 437       ;;
 438
 439     *)
 440       AC_MSG_ERROR([This appears to be XenServer $ovs_cv_xsversion, but only XenServer 5.6.100 or later is supported.  (If you are really using a supported version of XenServer, you may override this error message by specifying 'ovs_cv_xsversion=5.6.100' on the "configure" command line.)])
 441       ;;
 442   esac])
 443
 444 dnl OVS_MAKE_HAS_IF([if-true], [if-false])
 445 dnl
 446 dnl Checks whether make has the GNU make $(if condition,then,else) extension.
 447 dnl Runs 'if-true' if so, 'if-false' otherwise.
 448 AC_DEFUN([OVS_CHECK_MAKE_IF],
 449   [AC_CACHE_CHECK(
 450      [whether ${MAKE-make} has GNU make \$(if) extension],
 451      [ovs_cv_gnu_make_if],
 452      [cat <<'EOF' > conftest.mk
 453 conftest.out:
 454         echo $(if x,y,z) > conftest.out
 455 .PHONY: all
 456 EOF
 457       rm -f conftest.out
 458       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} -f conftest.mk all:"]) >&AS_MESSAGE_LOG_FD 2>&1
 459       ${MAKE-make} -f conftest.mk conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 460       AS_ECHO(["$as_me:$LINENO: conftest.out contains:"]) >&AS_MESSAGE_LOG_FD 2>&1
 461       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 462       result=`cat conftest.out`
 463       rm -f conftest.mk conftest.out
 464       if test "X$result" = "Xy"; then
 465         ovs_cv_gnu_make_if=yes
 466       else
 467         ovs_cv_gnu_make_if=no
 468       fi])])
 469
 470 dnl OVS_CHECK_GNU_MAKE
 471 dnl
 472 dnl Checks whether make is GNU make (because Linux kernel Makefiles
 473 dnl only work with GNU make).
 474 AC_DEFUN([OVS_CHECK_GNU_MAKE],
 475   [AC_CACHE_CHECK(
 476      [whether ${MAKE-make} is GNU make],
 477      [ovs_cv_gnu_make],
 478      [rm -f conftest.out
 479       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} --version:"]) >&AS_MESSAGE_LOG_FD 2>&1
 480       ${MAKE-make} --version >conftest.out 2>&1
 481       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 482       result=`cat conftest.out`
 483       rm -f conftest.mk conftest.out
 484
 485       case $result in # (
 486         GNU*) ovs_cv_gnu_make=yes ;; # (
 487         *) ovs_cv_gnu_make=no ;;
 488       esac])
 489    AM_CONDITIONAL([GNU_MAKE], [test $ovs_cv_gnu_make = yes])])
 490
 491 dnl OVS_CHECK_SPARSE_TARGET
 492 dnl
 493 dnl The "cgcc" script from "sparse" isn't very good at detecting the
 494 dnl target for which the code is being built.  This helps it out.
 495 AC_DEFUN([OVS_CHECK_SPARSE_TARGET],
 496   [AC_CACHE_CHECK(
 497     [target hint for cgcc],
 498     [ac_cv_sparse_target],
 499     [AS_CASE([`$CC -dumpmachine 2>/dev/null`],
 500        [i?86-* | athlon-*], [ac_cv_sparse_target=x86],
 501        [x86_64-*], [ac_cv_sparse_target=x86_64],
 502        [ac_cv_sparse_target=other])])
 503    AS_CASE([$ac_cv_sparse_target],
 504      [x86], [SPARSEFLAGS= CGCCFLAGS=-target=i86],
 505      [x86_64], [SPARSEFLAGS=-m64 CGCCFLAGS=-target=x86_64],
 506      [SPARSEFLAGS= CGCCFLAGS=])
 507    AC_SUBST([SPARSEFLAGS])
 508    AC_SUBST([CGCCFLAGS])])
 509
 510 dnl OVS_SPARSE_EXTRA_INCLUDES
 511 dnl
 512 dnl The cgcc script from "sparse" does not search gcc's default
 513 dnl search path. Get the default search path from GCC and pass
 514 dnl them to sparse.
 515 AC_DEFUN([OVS_SPARSE_EXTRA_INCLUDES],
 516     AC_SUBST([SPARSE_EXTRA_INCLUDES],
 517            [`$CC -v -E - </dev/null 2>&1 >/dev/null | sed -n -e '/^#include.*search.*starts.*here:/,/^End.*of.*search.*list\./s/^ \(.*\)/-I \1/p' |grep -v /usr/lib | grep -x -v '\-I /usr/include' | tr \\\n ' ' `] ))
 518
 519 dnl OVS_ENABLE_SPARSE
 520 AC_DEFUN([OVS_ENABLE_SPARSE],
 521   [AC_REQUIRE([OVS_CHECK_SPARSE_TARGET])
 522    AC_REQUIRE([OVS_CHECK_MAKE_IF])
 523    AC_REQUIRE([OVS_SPARSE_EXTRA_INCLUDES])
 524    : ${SPARSE=sparse}
 525    AC_SUBST([SPARSE])
 526    AC_CONFIG_COMMANDS_PRE(
 527      [if test $ovs_cv_gnu_make_if = yes; then
 528         CC='$(if $(C),REAL_CC="'"$CC"'" CHECK="$(SPARSE) -I $(top_srcdir)/include/sparse $(SPARSEFLAGS) $(SPARSE_EXTRA_INCLUDES) " cgcc $(CGCCFLAGS),'"$CC"')'
 529       fi])])