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([$KSRC/include/linux/netdevice.h], [skb_gso_segment])
 229   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [can_checksum_protocol])
 230   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [netif_skb_features])
 231   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [netif_needs_gso])
 232
 233   OVS_GREP_IFELSE([$KSRC/include/linux/rcupdate.h], [rcu_read_lock_held], [],
 234                   [OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h],
 235                                    [rcu_read_lock_held])])
 236
 237   # Check for the proto_data_valid member in struct sk_buff.  The [^@]
 238   # is necessary because some versions of this header remove the
 239   # member but retain the kerneldoc comment that describes it (which
 240   # starts with @).  The brackets must be doubled because of m4
 241   # quoting rules.
 242   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [[[^@]]proto_data_valid],
 243                   [OVS_DEFINE([HAVE_PROTO_DATA_VALID])])
 244   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [raw],
 245                   [OVS_DEFINE([HAVE_MAC_RAW])])
 246   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_dst(],
 247                   [OVS_DEFINE([HAVE_SKB_DST_ACCESSOR_FUNCS])])
 248   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
 249                   [skb_copy_from_linear_data_offset])
 250   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
 251                   [skb_reset_tail_pointer])
 252   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_cow_head])
 253   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_transport_header],
 254                   [OVS_DEFINE([HAVE_SKBUFF_HEADER_HELPERS])])
 255   OVS_GREP_IFELSE([$KSRC/include/linux/icmpv6.h], [icmp6_hdr],
 256                   [OVS_DEFINE([HAVE_ICMP6_HDR])])
 257   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_warn_if_lro],
 258                   [OVS_DEFINE([HAVE_SKB_WARN_LRO])])
 259   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [consume_skb])
 260   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_frag_page])
 261   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_reset_mac_len])
 262
 263   OVS_GREP_IFELSE([$KSRC/include/linux/string.h], [kmemdup], [],
 264                   [OVS_GREP_IFELSE([$KSRC/include/linux/slab.h], [kmemdup])])
 265
 266   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [bool],
 267                   [OVS_DEFINE([HAVE_BOOL_TYPE])])
 268   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [__wsum],
 269                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
 270   OVS_GREP_IFELSE([$KSRC/include/uapi/linux/types.h], [__wsum],
 271                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
 272
 273   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_replace4])
 274   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_unfold])
 275
 276   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [NLA_NUL_STRING])
 277   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_get_be16])
 278   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be16])
 279   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be32])
 280   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be64])
 281   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_find_nested])
 282
 283   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [ADD_ALL_VLANS_CMD],
 284                   [OVS_DEFINE([HAVE_VLAN_BUG_WORKAROUND])])
 285
 286   OVS_GREP_IFELSE([$KSRC/include/linux/percpu.h], [this_cpu_ptr])
 287
 288   OVS_GREP_IFELSE([$KSRC/include/linux/openvswitch.h], [openvswitch_handle_frame_hook],
 289                   [OVS_DEFINE([HAVE_RHEL_OVS_HOOK])])
 290
 291   OVS_CHECK_LOG2_H
 292
 293   if cmp -s datapath/linux/kcompat.h.new \
 294             datapath/linux/kcompat.h >/dev/null 2>&1; then
 295     rm datapath/linux/kcompat.h.new
 296   else
 297     mv datapath/linux/kcompat.h.new datapath/linux/kcompat.h
 298   fi
 299 ])
 300
 301 dnl Checks for net/if_packet.h.
 302 AC_DEFUN([OVS_CHECK_IF_PACKET],
 303   [AC_CHECK_HEADER([net/if_packet.h],
 304                    [HAVE_IF_PACKET=yes],
 305                    [HAVE_IF_PACKET=no])
 306    AM_CONDITIONAL([HAVE_IF_PACKET], [test "$HAVE_IF_PACKET" = yes])
 307    if test "$HAVE_IF_PACKET" = yes; then
 308       AC_DEFINE([HAVE_IF_PACKET], [1],
 309                 [Define to 1 if net/if_packet.h is available.])
 310    fi])
 311
 312 dnl Checks for net/if_dl.h.
 313 dnl
 314 dnl (We use this as a proxy for checking whether we're building on FreeBSD.)
 315 AC_DEFUN([OVS_CHECK_IF_DL],
 316   [AC_CHECK_HEADER([net/if_dl.h],
 317                    [HAVE_IF_DL=yes],
 318                    [HAVE_IF_DL=no])
 319    AM_CONDITIONAL([HAVE_IF_DL], [test "$HAVE_IF_DL" = yes])
 320    if test "$HAVE_IF_DL" = yes; then
 321       AC_DEFINE([HAVE_IF_DL], [1],
 322                 [Define to 1 if net/if_dl.h is available.])
 323
 324       # On FreeBSD we use libpcap to access network devices.
 325       AC_SEARCH_LIBS([pcap_open_live], [pcap])
 326    fi])
 327
 328 dnl Checks for buggy strtok_r.
 329 dnl
 330 dnl Some versions of glibc 2.7 has a bug in strtok_r when compiling
 331 dnl with optimization that can cause segfaults:
 332 dnl
 333 dnl http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
 334 AC_DEFUN([OVS_CHECK_STRTOK_R],
 335   [AC_CACHE_CHECK(
 336      [whether strtok_r macro segfaults on some inputs],
 337      [ovs_cv_strtok_r_bug],
 338      [AC_RUN_IFELSE(
 339         [AC_LANG_PROGRAM([#include <stdio.h>
 340                           #include <string.h>
 341                          ],
 342                          [[char string[] = ":::";
 343                            char *save_ptr = (char *) 0xc0ffee;
 344                            char *token1, *token2;
 345                            token1 = strtok_r(string, ":", &save_ptr);
 346                            token2 = strtok_r(NULL, ":", &save_ptr);
 347                            freopen ("/dev/null", "w", stdout);
 348                            printf ("%s %s\n", token1, token2);
 349                            return 0;
 350                           ]])],
 351         [ovs_cv_strtok_r_bug=no],
 352         [ovs_cv_strtok_r_bug=yes],
 353         [ovs_cv_strtok_r_bug=yes])])
 354    if test $ovs_cv_strtok_r_bug = yes; then
 355      AC_DEFINE([HAVE_STRTOK_R_BUG], [1],
 356                [Define if strtok_r macro segfaults on some inputs])
 357    fi
 358 ])
 359
 360 dnl ----------------------------------------------------------------------
 361 dnl These macros are from GNU PSPP, with the following original license:
 362 dnl Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
 363 dnl This file is free software; the Free Software Foundation
 364 dnl gives unlimited permission to copy and/or distribute it,
 365 dnl with or without modifications, as long as this notice is preserved.
 366
 367 dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
 368 dnl Check whether the given C compiler OPTION is accepted.
 369 dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
 370 AC_DEFUN([OVS_CHECK_CC_OPTION],
 371 [
 372   m4_define([ovs_cv_name], [ovs_cv_[]m4_translit([$1], [-], [_])])dnl
 373   AC_CACHE_CHECK([whether $CC accepts $1], [ovs_cv_name],
 374     [ovs_save_CFLAGS="$CFLAGS"
 375      CFLAGS="$CFLAGS $1"
 376      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [ovs_cv_name[]=yes], [ovs_cv_name[]=no])
 377      CFLAGS="$ovs_save_CFLAGS"])
 378   if test $ovs_cv_name = yes; then
 379     m4_if([$2], [], [:], [$2])
 380   else
 381     m4_if([$3], [], [:], [$3])
 382   fi
 383 ])
 384
 385 dnl OVS_ENABLE_OPTION([OPTION])
 386 dnl Check whether the given C compiler OPTION is accepted.
 387 dnl If so, add it to WARNING_FLAGS.
 388 dnl Example: OVS_ENABLE_OPTION([-Wdeclaration-after-statement])
 389 AC_DEFUN([OVS_ENABLE_OPTION],
 390   [OVS_CHECK_CC_OPTION([$1], [WARNING_FLAGS="$WARNING_FLAGS $1"])
 391    AC_SUBST([WARNING_FLAGS])])
 392
 393 dnl OVS_CONDITIONAL_CC_OPTION([OPTION], [CONDITIONAL])
 394 dnl Check whether the given C compiler OPTION is accepted.
 395 dnl If so, enable the given Automake CONDITIONAL.
 396
 397 dnl Example: OVS_CONDITIONAL_CC_OPTION([-Wno-unused], [HAVE_WNO_UNUSED])
 398 AC_DEFUN([OVS_CONDITIONAL_CC_OPTION],
 399   [OVS_CHECK_CC_OPTION(
 400     [$1], [ovs_have_cc_option=yes], [ovs_have_cc_option=no])
 401    AM_CONDITIONAL([$2], [test $ovs_have_cc_option = yes])])
 402 dnl ----------------------------------------------------------------------
 403
 404 dnl Check for too-old XenServer.
 405 AC_DEFUN([OVS_CHECK_XENSERVER_VERSION],
 406   [AC_CACHE_CHECK([XenServer release], [ovs_cv_xsversion],
 407     [if test -e /etc/redhat-release; then
 408        ovs_cv_xsversion=`sed -n 's/^XenServer DDK release \([[^-]]*\)-.*/\1/p' /etc/redhat-release`
 409      fi
 410      if test -z "$ovs_cv_xsversion"; then
 411        ovs_cv_xsversion=none
 412      fi])
 413   case $ovs_cv_xsversion in
 414     none)
 415       ;;
 416
 417     [[1-9]][[0-9]]* |                    dnl XenServer 10 or later
 418     [[6-9]]* |                           dnl XenServer 6 or later
 419     5.[[7-9]]* |                         dnl XenServer 5.7 or later
 420     5.6.[[1-9]][[0-9]][[0-9]][[0-9]]* |  dnl XenServer 5.6.1000 or later
 421     5.6.[[2-9]][[0-9]][[0-9]]* |         dnl XenServer 5.6.200 or later
 422     5.6.1[[0-9]][[0-9]])                 dnl Xenserver 5.6.100 or later
 423       ;;
 424
 425     *)
 426       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.)])
 427       ;;
 428   esac])
 429
 430 dnl OVS_MAKE_HAS_IF([if-true], [if-false])
 431 dnl
 432 dnl Checks whether make has the GNU make $(if condition,then,else) extension.
 433 dnl Runs 'if-true' if so, 'if-false' otherwise.
 434 AC_DEFUN([OVS_CHECK_MAKE_IF],
 435   [AC_CACHE_CHECK(
 436      [whether ${MAKE-make} has GNU make \$(if) extension],
 437      [ovs_cv_gnu_make_if],
 438      [cat <<'EOF' > conftest.mk
 439 conftest.out:
 440         echo $(if x,y,z) > conftest.out
 441 .PHONY: all
 442 EOF
 443       rm -f conftest.out
 444       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} -f conftest.mk all:"]) >&AS_MESSAGE_LOG_FD 2>&1
 445       ${MAKE-make} -f conftest.mk conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 446       AS_ECHO(["$as_me:$LINENO: conftest.out contains:"]) >&AS_MESSAGE_LOG_FD 2>&1
 447       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 448       result=`cat conftest.out`
 449       rm -f conftest.mk conftest.out
 450       if test "X$result" = "Xy"; then
 451         ovs_cv_gnu_make_if=yes
 452       else
 453         ovs_cv_gnu_make_if=no
 454       fi])])
 455
 456 dnl OVS_CHECK_GNU_MAKE
 457 dnl
 458 dnl Checks whether make is GNU make (because Linux kernel Makefiles
 459 dnl only work with GNU make).
 460 AC_DEFUN([OVS_CHECK_GNU_MAKE],
 461   [AC_CACHE_CHECK(
 462      [whether ${MAKE-make} is GNU make],
 463      [ovs_cv_gnu_make],
 464      [rm -f conftest.out
 465       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} --version:"]) >&AS_MESSAGE_LOG_FD 2>&1
 466       ${MAKE-make} --version >conftest.out 2>&1
 467       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 468       result=`cat conftest.out`
 469       rm -f conftest.mk conftest.out
 470
 471       case $result in # (
 472         GNU*) ovs_cv_gnu_make=yes ;; # (
 473         *) ovs_cv_gnu_make=no ;;
 474       esac])
 475    AM_CONDITIONAL([GNU_MAKE], [test $ovs_cv_gnu_make = yes])])
 476
 477 dnl OVS_CHECK_SPARSE_TARGET
 478 dnl
 479 dnl The "cgcc" script from "sparse" isn't very good at detecting the
 480 dnl target for which the code is being built.  This helps it out.
 481 AC_DEFUN([OVS_CHECK_SPARSE_TARGET],
 482   [AC_CACHE_CHECK(
 483     [target hint for cgcc],
 484     [ac_cv_sparse_target],
 485     [AS_CASE([`$CC -dumpmachine 2>/dev/null`],
 486        [i?86-* | athlon-*], [ac_cv_sparse_target=x86],
 487        [x86_64-*], [ac_cv_sparse_target=x86_64],
 488        [ac_cv_sparse_target=other])])
 489    AS_CASE([$ac_cv_sparse_target],
 490      [x86], [SPARSEFLAGS= CGCCFLAGS=-target=i86],
 491      [x86_64], [SPARSEFLAGS=-m64 CGCCFLAGS=-target=x86_64],
 492      [SPARSEFLAGS= CGCCFLAGS=])
 493    AC_SUBST([SPARSEFLAGS])
 494    AC_SUBST([CGCCFLAGS])])
 495
 496 dnl OVS_SPARSE_EXTRA_INCLUDES
 497 dnl
 498 dnl The cgcc script from "sparse" does not search gcc's default
 499 dnl search path. Get the default search path from GCC and pass
 500 dnl them to sparse.
 501 AC_DEFUN([OVS_SPARSE_EXTRA_INCLUDES],
 502     AC_SUBST([SPARSE_EXTRA_INCLUDES],
 503            [`$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 ' ' `] ))
 504
 505 dnl OVS_ENABLE_SPARSE
 506 AC_DEFUN([OVS_ENABLE_SPARSE],
 507   [AC_REQUIRE([OVS_CHECK_SPARSE_TARGET])
 508    AC_REQUIRE([OVS_CHECK_MAKE_IF])
 509    AC_REQUIRE([OVS_SPARSE_EXTRA_INCLUDES])
 510    : ${SPARSE=sparse}
 511    AC_SUBST([SPARSE])
 512    AC_CONFIG_COMMANDS_PRE(
 513      [if test $ovs_cv_gnu_make_if = yes; then
 514         CC='$(if $(C),REAL_CC="'"$CC"'" CHECK="$(SPARSE) -I $(top_srcdir)/include/sparse $(SPARSEFLAGS) $(SPARSE_EXTRA_INCLUDES) " cgcc $(CGCCFLAGS),'"$CC"')'
 515       fi])])