acinclude.m4

   1 # -*- autoconf -*-
   2
   3 # Copyright (c) 2008, 2009, 2010 Nicira Networks.
   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_CHECK_LINUX26
  18 dnl
  19 dnl Configure linux kernel source tree
  20 AC_DEFUN([OVS_CHECK_LINUX26], [
  21   AC_ARG_WITH([l26],
  22               [AC_HELP_STRING([--with-l26=/path/to/linux-2.6],
  23                               [Specify the linux 2.6 kernel sources])],
  24               [KBUILD26="$withval"], [KBUILD26=])dnl
  25   if test -n "$KBUILD26"; then
  26     KBUILD26=`eval echo "$KBUILD26"`
  27     case $KBUILD26 in
  28         /*) ;;
  29         *) KBUILD26=`pwd`/$KBUILD26 ;;
  30     esac
  31
  32     # The build directory is what the user provided.
  33     # Make sure that it exists.
  34     AC_MSG_CHECKING([for Linux 2.6 build directory])
  35     if test -d "$KBUILD26"; then
  36         AC_MSG_RESULT([$KBUILD26])
  37         AC_SUBST(KBUILD26)
  38     else
  39         AC_MSG_RESULT([no])
  40         AC_ERROR([source dir $KBUILD26 doesn't exist])
  41     fi
  42
  43     # Debian breaks kernel headers into "source" header and "build" headers.
  44     # We want the source headers, but $KBUILD26 gives us the "build" headers.
  45     # Use heuristics to find the source headers.
  46     AC_MSG_CHECKING([for Linux 2.6 source directory])
  47     KSRC26=$KBUILD26
  48     if test ! -e $KSRC26/include/linux/kernel.h; then
  49       case `echo "$KBUILD26" | sed 's,/*$,,'` in # (
  50         */build)
  51           KSRC26=`echo "$KBUILD26" | sed 's,/build/*$,/source,'`
  52           ;; # (
  53         *)
  54           KSRC26=`(cd $KBUILD26 && pwd -P) | sed 's,-[[^-]]*$,-common,'`
  55           ;;
  56       esac
  57       if test ! -e $KSRC26/include/linux/kernel.h; then
  58         AC_MSG_ERROR([cannot find source directory])
  59       fi
  60     fi
  61     AC_MSG_RESULT([$KSRC26])
  62
  63     AC_MSG_CHECKING([for kernel version])
  64     patchlevel=`sed -n 's/^PATCHLEVEL = //p' "$KSRC26/Makefile"`
  65     sublevel=`sed -n 's/^SUBLEVEL = //p' "$KSRC26/Makefile"`
  66     if test -z "$patchlevel" || test -z "$sublevel"; then
  67        AC_ERROR([cannot determine kernel version])
  68     fi
  69     AC_MSG_RESULT([2.$patchlevel.$sublevel])
  70     if test "2.$patchlevel" != '2.6'; then
  71        if test "$BUILD26" = "$KSRC26"; then
  72          AC_ERROR([Linux kernel in $KBUILD26 is not version 2.6])
  73        else
  74          AC_ERROR([Linux kernel in build tree $KBUILD26 (source tree $KSRC26) is not version 2.6])
  75        fi
  76     fi
  77     if test ! -e "$KBUILD26"/include/linux/version.h || \
  78        (test ! -e "$KBUILD26"/include/linux/autoconf.h && \
  79         test ! -e "$KBUILD26"/include/generated/autoconf.h); then
  80         AC_MSG_ERROR([Linux kernel source in $KBUILD26 is not configured])
  81     fi
  82     OVS_CHECK_LINUX26_COMPAT
  83   fi
  84   AM_CONDITIONAL(L26_ENABLED, test -n "$KBUILD26")
  85 ])
  86
  87 dnl OVS_GREP_IFELSE(FILE, REGEX, IF-MATCH, IF-NO-MATCH)
  88 dnl
  89 dnl Greps FILE for REGEX.  If it matches, runs IF-MATCH, otherwise IF-NO-MATCH.
  90 AC_DEFUN([OVS_GREP_IFELSE], [
  91   AC_MSG_CHECKING([whether $2 matches in $1])
  92   grep '$2' $1 >/dev/null 2>&1
  93   status=$?
  94   case $status in
  95     0)
  96       AC_MSG_RESULT([yes])
  97       $3
  98       ;;
  99     1)
 100       AC_MSG_RESULT([no])
 101       $4
 102       ;;
 103     *)
 104       AC_MSG_ERROR([grep exited with status $status])
 105       ;;
 106   esac
 107 ])
 108
 109 dnl OVS_DEFINE(NAME)
 110 dnl
 111 dnl Defines NAME to 1 in kcompat.h.
 112 AC_DEFUN([OVS_DEFINE], [
 113   echo '#define $1 1' >> datapath/linux-2.6/kcompat.h.new
 114 ])
 115
 116 AC_DEFUN([OVS_CHECK_VETH], [
 117   AC_MSG_CHECKING([whether to build veth module])
 118   if test "$sublevel" = 18; then
 119     AC_MSG_RESULT([yes])
 120     AC_SUBST([BUILD_VETH], 1)
 121   else
 122     AC_MSG_RESULT([no])
 123   fi
 124 ])
 125
 126 AC_DEFUN([OVS_CHECK_LOG2_H], [
 127   AC_MSG_CHECKING([for $KSRC26/include/linux/log2.h])
 128   if test -e $KSRC26/include/linux/log2.h; then
 129     AC_MSG_RESULT([yes])
 130     OVS_DEFINE([HAVE_LOG2_H])
 131   else
 132     AC_MSG_RESULT([no])
 133   fi
 134 ])
 135
 136 dnl OVS_CHECK_LINUX26_COMPAT
 137 dnl
 138 dnl Runs various Autoconf checks on the Linux 2.6 kernel source in
 139 dnl the directory in $KBUILD26.
 140 AC_DEFUN([OVS_CHECK_LINUX26_COMPAT], [
 141   rm -f datapath/linux-2.6/kcompat.h.new
 142   mkdir -p datapath/linux-2.6
 143   : > datapath/linux-2.6/kcompat.h.new
 144
 145   OVS_GREP_IFELSE([$KSRC26/include/linux/err.h], [ERR_CAST],
 146                   [OVS_DEFINE([HAVE_ERR_CAST])])
 147
 148   OVS_GREP_IFELSE([$KSRC26/include/linux/in.h], [ipv4_is_multicast],
 149                   [OVS_DEFINE([HAVE_IPV4_IS_MULTICAST])])
 150
 151   OVS_GREP_IFELSE([$KSRC26/include/linux/netdevice.h], [dev_disable_lro],
 152                   [OVS_DEFINE([HAVE_DEV_DISABLE_LRO])])
 153
 154   # Check for the proto_data_valid member in struct sk_buff.  The [^@]
 155   # is necessary because some versions of this header remove the
 156   # member but retain the kerneldoc comment that describes it (which
 157   # starts with @).  The brackets must be doubled because of m4
 158   # quoting rules.
 159   OVS_GREP_IFELSE([$KSRC26/include/linux/skbuff.h], [[[^@]]proto_data_valid],
 160                   [OVS_DEFINE([HAVE_PROTO_DATA_VALID])])
 161   OVS_GREP_IFELSE([$KSRC26/include/linux/skbuff.h], [raw],
 162                   [OVS_DEFINE([HAVE_MAC_RAW])])
 163   OVS_GREP_IFELSE([$KSRC26/include/linux/skbuff.h],
 164                   [skb_copy_from_linear_data_offset],
 165                   [OVS_DEFINE([HAVE_SKB_COPY_FROM_LINEAR_DATA_OFFSET])])
 166   OVS_GREP_IFELSE([$KSRC26/include/linux/skbuff.h], [skb_cow],
 167                   [OVS_DEFINE([HAVE_SKB_COW])])
 168   OVS_GREP_IFELSE([$KSRC26/include/linux/skbuff.h], [skb_transport_header],
 169                   [OVS_DEFINE([HAVE_SKBUFF_HEADER_HELPERS])])
 170   OVS_GREP_IFELSE([$KSRC26/include/linux/skbuff.h], [skb_warn_if_lro],
 171                   [OVS_DEFINE([HAVE_SKB_WARN_LRO])])
 172
 173   OVS_GREP_IFELSE([$KSRC26/include/linux/string.h $KSRC26/include/linux/slab.h],
 174                   [kmemdup], [OVS_DEFINE([HAVE_KMEMDUP])])
 175
 176   OVS_GREP_IFELSE([$KSRC26/include/linux/types.h], [bool],
 177                   [OVS_DEFINE([HAVE_BOOL_TYPE])])
 178
 179   OVS_GREP_IFELSE([$KSRC26/include/net/checksum.h], [csum_unfold],
 180                   [OVS_DEFINE([HAVE_CSUM_UNFOLD])])
 181
 182   OVS_GREP_IFELSE([$KSRC26/include/net/netlink.h], [NLA_NUL_STRING],
 183                   [OVS_DEFINE([HAVE_NLA_NUL_STRING])])
 184   OVS_GREP_IFELSE([$KSRC26/include/net/netlink.h], [nla_get_be16],
 185                   [OVS_DEFINE([HAVE_NLA_GET_BE16])])
 186
 187   OVS_CHECK_LOG2_H
 188   OVS_CHECK_VETH
 189
 190   if cmp -s datapath/linux-2.6/kcompat.h.new \
 191             datapath/linux-2.6/kcompat.h >/dev/null 2>&1; then
 192     rm datapath/linux-2.6/kcompat.h.new
 193   else
 194     mv datapath/linux-2.6/kcompat.h.new datapath/linux-2.6/kcompat.h
 195   fi
 196 ])
 197
 198 dnl Checks for net/if_packet.h.
 199 AC_DEFUN([OVS_CHECK_IF_PACKET],
 200   [AC_CHECK_HEADER([net/if_packet.h],
 201                    [HAVE_IF_PACKET=yes],
 202                    [HAVE_IF_PACKET=no])
 203    AM_CONDITIONAL([HAVE_IF_PACKET], [test "$HAVE_IF_PACKET" = yes])
 204    if test "$HAVE_IF_PACKET" = yes; then
 205       AC_DEFINE([HAVE_IF_PACKET], [1],
 206                 [Define to 1 if net/if_packet.h is available.])
 207    fi])
 208
 209 dnl Checks for buggy strtok_r.
 210 dnl
 211 dnl Some versions of glibc 2.7 has a bug in strtok_r when compiling
 212 dnl with optimization that can cause segfaults:
 213 dnl
 214 dnl http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
 215 AC_DEFUN([OVS_CHECK_STRTOK_R],
 216   [AC_CACHE_CHECK(
 217      [whether strtok_r macro segfaults on some inputs],
 218      [ovs_cv_strtok_r_bug],
 219      [AC_RUN_IFELSE(
 220         [AC_LANG_PROGRAM([#include <stdio.h>
 221                           #include <string.h>
 222                          ],
 223                          [[char string[] = ":::";
 224                            char *save_ptr = (char *) 0xc0ffee;
 225                            char *token1, *token2;
 226                            token1 = strtok_r(string, ":", &save_ptr);
 227                            token2 = strtok_r(NULL, ":", &save_ptr);
 228                            freopen ("/dev/null", "w", stdout);
 229                            printf ("%s %s\n", token1, token2);
 230                            return 0;
 231                           ]])],
 232         [ovs_cv_strtok_r_bug=no],
 233         [ovs_cv_strtok_r_bug=yes],
 234         [ovs_cv_strtok_r_bug=yes])])
 235    if test $ovs_cv_strtok_r_bug = yes; then
 236      AC_DEFINE([HAVE_STRTOK_R_BUG], [1],
 237                [Define if strtok_r macro segfaults on some inputs])
 238    fi
 239 ])
 240
 241 dnl ----------------------------------------------------------------------
 242 dnl These macros are from GNU PSPP, with the following original license:
 243 dnl Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
 244 dnl This file is free software; the Free Software Foundation
 245 dnl gives unlimited permission to copy and/or distribute it,
 246 dnl with or without modifications, as long as this notice is preserved.
 247
 248 dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
 249 dnl Check whether the given C compiler OPTION is accepted.
 250 dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
 251 AC_DEFUN([OVS_CHECK_CC_OPTION],
 252 [
 253   m4_define([ovs_cv_name], [ovs_cv_[]m4_translit([$1], [-], [_])])dnl
 254   AC_CACHE_CHECK([whether $CC accepts $1], [ovs_cv_name],
 255     [ovs_save_CFLAGS="$CFLAGS"
 256      CFLAGS="$CFLAGS $1"
 257      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [ovs_cv_name[]=yes], [ovs_cv_name[]=no])
 258      CFLAGS="$ovs_save_CFLAGS"])
 259   if test $ovs_cv_name = yes; then
 260     m4_if([$2], [], [:], [$2])
 261   else
 262     m4_if([$3], [], [:], [$3])
 263   fi
 264 ])
 265
 266 dnl OVS_ENABLE_OPTION([OPTION])
 267 dnl Check whether the given C compiler OPTION is accepted.
 268 dnl If so, add it to WARNING_FLAGS.
 269 dnl Example: OVS_ENABLE_OPTION([-Wdeclaration-after-statement])
 270 AC_DEFUN([OVS_ENABLE_OPTION],
 271   [OVS_CHECK_CC_OPTION([$1], [WARNING_FLAGS="$WARNING_FLAGS $1"])
 272    AC_SUBST([WARNING_FLAGS])])
 273
 274 dnl OVS_CONDITIONAL_CC_OPTION([OPTION], [CONDITIONAL])
 275 dnl Check whether the given C compiler OPTION is accepted.
 276 dnl If so, enable the given Automake CONDITIONAL.
 277
 278 dnl Example: OVS_CONDITIONAL_CC_OPTION([-Wno-unused], [HAVE_WNO_UNUSED])
 279 AC_DEFUN([OVS_CONDITIONAL_CC_OPTION],
 280   [OVS_CHECK_CC_OPTION(
 281     [$1], [ovs_have_cc_option=yes], [ovs_have_cc_option=no])
 282    AM_CONDITIONAL([$2], [test $ovs_have_cc_option = yes])])
 283 dnl ----------------------------------------------------------------------