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 "$version" -ge 3; then
 137        if test "$version" = 3 && test "$patchlevel" -le 11; then
 138           : # Linux 3.x
 139        else
 140          AC_ERROR([Linux kernel in $KBUILD is version $kversion, but version newer than 3.11.x is not supported])
 141        fi
 142     else
 143        if test "$version" -le 1 || test "$patchlevel" -le 5 || test "$sublevel" -le 31; then
 144          AC_ERROR([Linux kernel in $KBUILD is version $kversion, but version 2.6.32 or later is required])
 145        else
 146          : # Linux 2.6.x
 147        fi
 148     fi
 149     if (test ! -e "$KBUILD"/include/linux/version.h && \
 150         test ! -e "$KBUILD"/include/generated/uapi/linux/version.h)|| \
 151        (test ! -e "$KBUILD"/include/linux/autoconf.h && \
 152         test ! -e "$KBUILD"/include/generated/autoconf.h); then
 153         AC_MSG_ERROR([Linux kernel source in $KBUILD is not configured])
 154     fi
 155     OVS_CHECK_LINUX_COMPAT
 156   fi
 157   AM_CONDITIONAL(LINUX_ENABLED, test -n "$KBUILD")
 158 ])
 159
 160 dnl OVS_GREP_IFELSE(FILE, REGEX, [IF-MATCH], [IF-NO-MATCH])
 161 dnl
 162 dnl Greps FILE for REGEX.  If it matches, runs IF-MATCH, otherwise IF-NO-MATCH.
 163 dnl If IF-MATCH is empty then it defines to OVS_DEFINE(HAVE_<REGEX>), with
 164 dnl <REGEX> translated to uppercase.
 165 AC_DEFUN([OVS_GREP_IFELSE], [
 166   AC_MSG_CHECKING([whether $2 matches in $1])
 167   if test -f $1; then
 168     grep '$2' $1 >/dev/null 2>&1
 169     status=$?
 170     case $status in
 171       0)
 172         AC_MSG_RESULT([yes])
 173         m4_if([$3], [], [OVS_DEFINE([HAVE_]m4_toupper([$2]))], [$3])
 174         ;;
 175       1)
 176         AC_MSG_RESULT([no])
 177         $4
 178         ;;
 179       *)
 180         AC_MSG_ERROR([grep exited with status $status])
 181         ;;
 182     esac
 183   else
 184     AC_MSG_RESULT([file not found])
 185     $4
 186   fi
 187 ])
 188
 189 dnl OVS_DEFINE(NAME)
 190 dnl
 191 dnl Defines NAME to 1 in kcompat.h.
 192 AC_DEFUN([OVS_DEFINE], [
 193   echo '#define $1 1' >> datapath/linux/kcompat.h.new
 194 ])
 195
 196 AC_DEFUN([OVS_CHECK_LOG2_H], [
 197   AC_MSG_CHECKING([for $KSRC/include/linux/log2.h])
 198   if test -e $KSRC/include/linux/log2.h; then
 199     AC_MSG_RESULT([yes])
 200     OVS_DEFINE([HAVE_LOG2_H])
 201   else
 202     AC_MSG_RESULT([no])
 203   fi
 204 ])
 205
 206 dnl OVS_CHECK_LINUX_COMPAT
 207 dnl
 208 dnl Runs various Autoconf checks on the Linux 2.6 kernel source in
 209 dnl the directory in $KBUILD.
 210 AC_DEFUN([OVS_CHECK_LINUX_COMPAT], [
 211   rm -f datapath/linux/kcompat.h.new
 212   mkdir -p datapath/linux
 213   : > datapath/linux/kcompat.h.new
 214
 215   OVS_GREP_IFELSE([$KSRC/arch/x86/include/asm/checksum_32.h], [src_err,],
 216                   [OVS_DEFINE([HAVE_CSUM_COPY_DBG])])
 217
 218   OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [ERR_CAST])
 219
 220   OVS_GREP_IFELSE([$KSRC/include/linux/etherdevice.h], [eth_hw_addr_random])
 221
 222   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_set_encap_proto])
 223
 224   OVS_GREP_IFELSE([$KSRC/include/linux/in.h], [ipv4_is_multicast])
 225
 226   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_disable_lro])
 227   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_stats])
 228   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_by_index_rcu])
 229   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [__skb_gso_segment])
 230   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [can_checksum_protocol])
 231
 232   OVS_GREP_IFELSE([$KSRC/include/linux/rcupdate.h], [rcu_read_lock_held], [],
 233                   [OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h],
 234                                    [rcu_read_lock_held])])
 235
 236   # Check for the proto_data_valid member in struct sk_buff.  The [^@]
 237   # is necessary because some versions of this header remove the
 238   # member but retain the kerneldoc comment that describes it (which
 239   # starts with @).  The brackets must be doubled because of m4
 240   # quoting rules.
 241   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [[[^@]]proto_data_valid],
 242                   [OVS_DEFINE([HAVE_PROTO_DATA_VALID])])
 243   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [rxhash])
 244   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_dst(],
 245                   [OVS_DEFINE([HAVE_SKB_DST_ACCESSOR_FUNCS])])
 246   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
 247                   [skb_copy_from_linear_data_offset])
 248   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
 249                   [skb_reset_tail_pointer])
 250   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_cow_head])
 251   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_transport_header],
 252                   [OVS_DEFINE([HAVE_SKBUFF_HEADER_HELPERS])])
 253   OVS_GREP_IFELSE([$KSRC/include/linux/icmpv6.h], [icmp6_hdr],
 254                   [OVS_DEFINE([HAVE_ICMP6_HDR])])
 255   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_warn_if_lro],
 256                   [OVS_DEFINE([HAVE_SKB_WARN_LRO])])
 257   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [consume_skb])
 258   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_frag_page])
 259   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_reset_mac_len])
 260   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_unclone])
 261
 262   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [bool],
 263                   [OVS_DEFINE([HAVE_BOOL_TYPE])])
 264   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [__wsum],
 265                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
 266   OVS_GREP_IFELSE([$KSRC/include/uapi/linux/types.h], [__wsum],
 267                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
 268
 269   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_replace4])
 270   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_unfold])
 271
 272   OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [parallel_ops])
 273   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_get_be16])
 274   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be16])
 275   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be32])
 276   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be64])
 277   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_find_nested])
 278
 279   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [ADD_ALL_VLANS_CMD],
 280                   [OVS_DEFINE([HAVE_VLAN_BUG_WORKAROUND])])
 281
 282   OVS_GREP_IFELSE([$KSRC/include/linux/percpu.h], [this_cpu_ptr])
 283
 284   OVS_GREP_IFELSE([$KSRC/include/linux/openvswitch.h], [openvswitch_handle_frame_hook],
 285                   [OVS_DEFINE([HAVE_RHEL_OVS_HOOK])])
 286
 287   OVS_CHECK_LOG2_H
 288
 289   if cmp -s datapath/linux/kcompat.h.new \
 290             datapath/linux/kcompat.h >/dev/null 2>&1; then
 291     rm datapath/linux/kcompat.h.new
 292   else
 293     mv datapath/linux/kcompat.h.new datapath/linux/kcompat.h
 294   fi
 295 ])
 296
 297 dnl Checks for net/if_packet.h.
 298 AC_DEFUN([OVS_CHECK_IF_PACKET],
 299   [AC_CHECK_HEADER([net/if_packet.h],
 300                    [HAVE_IF_PACKET=yes],
 301                    [HAVE_IF_PACKET=no])
 302    AM_CONDITIONAL([HAVE_IF_PACKET], [test "$HAVE_IF_PACKET" = yes])
 303    if test "$HAVE_IF_PACKET" = yes; then
 304       AC_DEFINE([HAVE_IF_PACKET], [1],
 305                 [Define to 1 if net/if_packet.h is available.])
 306    fi])
 307
 308 dnl Checks for net/if_dl.h.
 309 dnl
 310 dnl (We use this as a proxy for checking whether we're building on FreeBSD
 311 dnl or NetBSD.)
 312 AC_DEFUN([OVS_CHECK_IF_DL],
 313   [AC_CHECK_HEADER([net/if_dl.h],
 314                    [HAVE_IF_DL=yes],
 315                    [HAVE_IF_DL=no])
 316    AM_CONDITIONAL([HAVE_IF_DL], [test "$HAVE_IF_DL" = yes])
 317    if test "$HAVE_IF_DL" = yes; then
 318       AC_DEFINE([HAVE_IF_DL], [1],
 319                 [Define to 1 if net/if_dl.h is available.])
 320
 321       # On these platforms we use libpcap to access network devices.
 322       AC_SEARCH_LIBS([pcap_open_live], [pcap])
 323    fi])
 324
 325 dnl Checks for buggy strtok_r.
 326 dnl
 327 dnl Some versions of glibc 2.7 has a bug in strtok_r when compiling
 328 dnl with optimization that can cause segfaults:
 329 dnl
 330 dnl http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
 331 AC_DEFUN([OVS_CHECK_STRTOK_R],
 332   [AC_CACHE_CHECK(
 333      [whether strtok_r macro segfaults on some inputs],
 334      [ovs_cv_strtok_r_bug],
 335      [AC_RUN_IFELSE(
 336         [AC_LANG_PROGRAM([#include <stdio.h>
 337                           #include <string.h>
 338                          ],
 339                          [[char string[] = ":::";
 340                            char *save_ptr = (char *) 0xc0ffee;
 341                            char *token1, *token2;
 342                            token1 = strtok_r(string, ":", &save_ptr);
 343                            token2 = strtok_r(NULL, ":", &save_ptr);
 344                            freopen ("/dev/null", "w", stdout);
 345                            printf ("%s %s\n", token1, token2);
 346                            return 0;
 347                           ]])],
 348         [ovs_cv_strtok_r_bug=no],
 349         [ovs_cv_strtok_r_bug=yes],
 350         [ovs_cv_strtok_r_bug=yes])])
 351    if test $ovs_cv_strtok_r_bug = yes; then
 352      AC_DEFINE([HAVE_STRTOK_R_BUG], [1],
 353                [Define if strtok_r macro segfaults on some inputs])
 354    fi
 355 ])
 356
 357 dnl ----------------------------------------------------------------------
 358 dnl These macros are from GNU PSPP, with the following original license:
 359 dnl Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
 360 dnl This file is free software; the Free Software Foundation
 361 dnl gives unlimited permission to copy and/or distribute it,
 362 dnl with or without modifications, as long as this notice is preserved.
 363
 364 AC_DEFUN([_OVS_CHECK_CC_OPTION], [dnl
 365   m4_define([ovs_cv_name], [ovs_cv_[]m4_translit([$1], [-], [_])])dnl
 366   AC_CACHE_CHECK([whether $CC accepts $1], [ovs_cv_name],
 367     [ovs_save_CFLAGS="$CFLAGS"
 368      dnl Include -Werror in the compiler options, because without -Werror
 369      dnl clang's GCC-compatible compiler driver does not return a failure
 370      dnl exit status even though it complains about options it does not
 371      dnl understand.
 372      CFLAGS="$CFLAGS $WERROR $1"
 373      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [ovs_cv_name[]=yes], [ovs_cv_name[]=no])
 374      CFLAGS="$ovs_save_CFLAGS"])
 375   if test $ovs_cv_name = yes; then
 376     m4_if([$2], [], [:], [$2])
 377   else
 378     m4_if([$3], [], [:], [$3])
 379   fi
 380 ])
 381
 382 dnl OVS_CHECK_WERROR
 383 dnl
 384 dnl Check whether the C compiler accepts -Werror.
 385 dnl Sets $WERROR to "-Werror", if so, and otherwise to the empty string.
 386 AC_DEFUN([OVS_CHECK_WERROR],
 387   [WERROR=
 388    _OVS_CHECK_CC_OPTION([-Werror], [WERROR=-Werror])])
 389
 390 dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
 391 dnl Check whether the given C compiler OPTION is accepted.
 392 dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
 393 AC_DEFUN([OVS_CHECK_CC_OPTION],
 394   [AC_REQUIRE([OVS_CHECK_WERROR])
 395    _OVS_CHECK_CC_OPTION([$1], [$2], [$3])])
 396
 397 dnl OVS_ENABLE_OPTION([OPTION])
 398 dnl Check whether the given C compiler OPTION is accepted.
 399 dnl If so, add it to WARNING_FLAGS.
 400 dnl Example: OVS_ENABLE_OPTION([-Wdeclaration-after-statement])
 401 AC_DEFUN([OVS_ENABLE_OPTION],
 402   [OVS_CHECK_CC_OPTION([$1], [WARNING_FLAGS="$WARNING_FLAGS $1"])
 403    AC_SUBST([WARNING_FLAGS])])
 404
 405 dnl OVS_CONDITIONAL_CC_OPTION([OPTION], [CONDITIONAL])
 406 dnl Check whether the given C compiler OPTION is accepted.
 407 dnl If so, enable the given Automake CONDITIONAL.
 408
 409 dnl Example: OVS_CONDITIONAL_CC_OPTION([-Wno-unused], [HAVE_WNO_UNUSED])
 410 AC_DEFUN([OVS_CONDITIONAL_CC_OPTION],
 411   [OVS_CHECK_CC_OPTION(
 412     [$1], [ovs_have_cc_option=yes], [ovs_have_cc_option=no])
 413    AM_CONDITIONAL([$2], [test $ovs_have_cc_option = yes])])
 414 dnl ----------------------------------------------------------------------
 415
 416 dnl Check for too-old XenServer.
 417 AC_DEFUN([OVS_CHECK_XENSERVER_VERSION],
 418   [AC_CACHE_CHECK([XenServer release], [ovs_cv_xsversion],
 419     [if test -e /etc/redhat-release; then
 420        ovs_cv_xsversion=`sed -n 's/^XenServer DDK release \([[^-]]*\)-.*/\1/p' /etc/redhat-release`
 421      fi
 422      if test -z "$ovs_cv_xsversion"; then
 423        ovs_cv_xsversion=none
 424      fi])
 425   case $ovs_cv_xsversion in
 426     none)
 427       ;;
 428
 429     [[1-9]][[0-9]]* |                    dnl XenServer 10 or later
 430     [[6-9]]* |                           dnl XenServer 6 or later
 431     5.[[7-9]]* |                         dnl XenServer 5.7 or later
 432     5.6.[[1-9]][[0-9]][[0-9]][[0-9]]* |  dnl XenServer 5.6.1000 or later
 433     5.6.[[2-9]][[0-9]][[0-9]]* |         dnl XenServer 5.6.200 or later
 434     5.6.1[[0-9]][[0-9]])                 dnl Xenserver 5.6.100 or later
 435       ;;
 436
 437     *)
 438       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.)])
 439       ;;
 440   esac])
 441
 442 dnl OVS_MAKE_HAS_IF([if-true], [if-false])
 443 dnl
 444 dnl Checks whether make has the GNU make $(if condition,then,else) extension.
 445 dnl Runs 'if-true' if so, 'if-false' otherwise.
 446 AC_DEFUN([OVS_CHECK_MAKE_IF],
 447   [AC_CACHE_CHECK(
 448      [whether ${MAKE-make} has GNU make \$(if) extension],
 449      [ovs_cv_gnu_make_if],
 450      [cat <<'EOF' > conftest.mk
 451 conftest.out:
 452         echo $(if x,y,z) > conftest.out
 453 .PHONY: all
 454 EOF
 455       rm -f conftest.out
 456       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} -f conftest.mk all:"]) >&AS_MESSAGE_LOG_FD 2>&1
 457       ${MAKE-make} -f conftest.mk conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 458       AS_ECHO(["$as_me:$LINENO: conftest.out contains:"]) >&AS_MESSAGE_LOG_FD 2>&1
 459       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 460       result=`cat conftest.out`
 461       rm -f conftest.mk conftest.out
 462       if test "X$result" = "Xy"; then
 463         ovs_cv_gnu_make_if=yes
 464       else
 465         ovs_cv_gnu_make_if=no
 466       fi])])
 467
 468 dnl OVS_CHECK_GNU_MAKE
 469 dnl
 470 dnl Checks whether make is GNU make (because Linux kernel Makefiles
 471 dnl only work with GNU make).
 472 AC_DEFUN([OVS_CHECK_GNU_MAKE],
 473   [AC_CACHE_CHECK(
 474      [whether ${MAKE-make} is GNU make],
 475      [ovs_cv_gnu_make],
 476      [rm -f conftest.out
 477       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} --version:"]) >&AS_MESSAGE_LOG_FD 2>&1
 478       ${MAKE-make} --version >conftest.out 2>&1
 479       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
 480       result=`cat conftest.out`
 481       rm -f conftest.mk conftest.out
 482
 483       case $result in # (
 484         GNU*) ovs_cv_gnu_make=yes ;; # (
 485         *) ovs_cv_gnu_make=no ;;
 486       esac])
 487    AM_CONDITIONAL([GNU_MAKE], [test $ovs_cv_gnu_make = yes])])
 488
 489 dnl OVS_CHECK_SPARSE_TARGET
 490 dnl
 491 dnl The "cgcc" script from "sparse" isn't very good at detecting the
 492 dnl target for which the code is being built.  This helps it out.
 493 AC_DEFUN([OVS_CHECK_SPARSE_TARGET],
 494   [AC_CACHE_CHECK(
 495     [target hint for cgcc],
 496     [ac_cv_sparse_target],
 497     [AS_CASE([`$CC -dumpmachine 2>/dev/null`],
 498        [i?86-* | athlon-*], [ac_cv_sparse_target=x86],
 499        [x86_64-*], [ac_cv_sparse_target=x86_64],
 500        [ac_cv_sparse_target=other])])
 501    AS_CASE([$ac_cv_sparse_target],
 502      [x86], [SPARSEFLAGS= CGCCFLAGS=-target=i86],
 503      [x86_64], [SPARSEFLAGS=-m64 CGCCFLAGS=-target=x86_64],
 504      [SPARSEFLAGS= CGCCFLAGS=])
 505    AC_SUBST([SPARSEFLAGS])
 506    AC_SUBST([CGCCFLAGS])])
 507
 508 dnl OVS_SPARSE_EXTRA_INCLUDES
 509 dnl
 510 dnl The cgcc script from "sparse" does not search gcc's default
 511 dnl search path. Get the default search path from GCC and pass
 512 dnl them to sparse.
 513 AC_DEFUN([OVS_SPARSE_EXTRA_INCLUDES],
 514     AC_SUBST([SPARSE_EXTRA_INCLUDES],
 515            [`$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 ' ' `] ))
 516
 517 dnl OVS_ENABLE_SPARSE
 518 AC_DEFUN([OVS_ENABLE_SPARSE],
 519   [AC_REQUIRE([OVS_CHECK_SPARSE_TARGET])
 520    AC_REQUIRE([OVS_CHECK_MAKE_IF])
 521    AC_REQUIRE([OVS_SPARSE_EXTRA_INCLUDES])
 522    : ${SPARSE=sparse}
 523    AC_SUBST([SPARSE])
 524    AC_CONFIG_COMMANDS_PRE(
 525      [if test $ovs_cv_gnu_make_if = yes; then
 526         CC='$(if $(C),REAL_CC="'"$CC"'" CHECK="$(SPARSE) -I $(top_srcdir)/include/sparse $(SPARSEFLAGS) $(SPARSE_EXTRA_INCLUDES) " cgcc $(CGCCFLAGS),'"$CC"')'
 527       fi])])
 528
 529 dnl OVS_PTHREAD_SET_NAME
 530 dnl
 531 dnl This checks for three known variants of pthreads functions for setting
 532 dnl the name of the current thread:
 533 dnl
 534 dnl   glibc: int pthread_setname_np(pthread_t, const char *name);
 535 dnl   NetBSD: int pthread_setname_np(pthread_t, const char *format, void *arg);
 536 dnl   FreeBSD: int pthread_set_name_np(pthread_t, const char *name);
 537 dnl
 538 dnl For glibc and FreeBSD, the arguments are just a thread and its name.  For
 539 dnl NetBSD, 'format' is a printf() format string and 'arg' is an argument to
 540 dnl provide to it.
 541 dnl
 542 dnl This macro defines:
 543 dnl
 544 dnl    glibc: HAVE_GLIBC_PTHREAD_SETNAME_NP
 545 dnl    NetBSD: HAVE_NETBSD_PTHREAD_SETNAME_NP
 546 dnl    FreeBSD: HAVE_PTHREAD_SET_NAME_NP
 547 AC_DEFUN([OVS_CHECK_PTHREAD_SET_NAME],
 548   [AC_CHECK_FUNCS([pthread_set_name_np])
 549    if test $ac_cv_func_pthread_set_name_np != yes; then
 550      AC_CACHE_CHECK(
 551        [for pthread_setname_np() variant],
 552        [ovs_cv_pthread_setname_np],
 553        [AC_LINK_IFELSE(
 554          [AC_LANG_PROGRAM([#include <pthread.h>
 555   ], [pthread_setname_np(pthread_self(), "name");])],
 556          [ovs_cv_pthread_setname_np=glibc],
 557          [AC_LINK_IFELSE(
 558            [AC_LANG_PROGRAM([#include <pthread.h>
 559 ], [pthread_setname_np(pthread_self(), "%s", "name");])],
 560            [ovs_cv_pthread_setname_np=netbsd],
 561            [ovs_cv_pthread_setname_np=none])])])
 562      case $ovs_cv_pthread_setname_np in # (
 563        glibc)
 564           AC_DEFINE(
 565             [HAVE_GLIBC_PTHREAD_SETNAME_NP], [1],
 566             [Define to 1 if pthread_setname_np() is available and takes 2 parameters (like glibc).])
 567           ;; # (
 568        netbsd)
 569           AC_DEFINE(
 570             [HAVE_NETBSD_PTHREAD_SETNAME_NP], [1],
 571             [Define to 1 if pthread_setname_np() is available and takes 3 parameters (like NetBSD).])
 572           ;;
 573      esac
 574    fi])