datapath: Provide compatibility for kernels up to 3.17
[cascardo/ovs.git] / acinclude.m4
1 # -*- autoconf -*-
2
3 # Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 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$enable_Werror" = Xyes; then
25         OVS_CFLAGS="$OVS_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 17; then
138           : # Linux 3.x
139        else
140          AC_ERROR([Linux kernel in $KBUILD is version $kversion, but version newer than 3.17.x is not supported (please refer to the FAQ for advice)])
141        fi
142     else
143        if test "$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_CHECK_DPDK
161 dnl
162 dnl Configure DPDK source tree
163 AC_DEFUN([OVS_CHECK_DPDK], [
164   AC_ARG_WITH([dpdk],
165               [AC_HELP_STRING([--with-dpdk=/path/to/dpdk],
166                               [Specify the DPDK build directory])])
167
168   if test X"$with_dpdk" != X; then
169     RTE_SDK=$with_dpdk
170
171     DPDK_INCLUDE=$RTE_SDK/include
172     DPDK_LIB_DIR=$RTE_SDK/lib
173     DPDK_LIB=-lintel_dpdk
174
175     ovs_save_CFLAGS="$CFLAGS"
176     ovs_save_LDFLAGS="$LDFLAGS"
177     LDFLAGS="$LDFLAGS -L$DPDK_LIB_DIR"
178     CFLAGS="$CFLAGS -I$DPDK_INCLUDE"
179
180     # On some systems we have to add -ldl to link with dpdk
181     #
182     # This code, at first, tries to link without -ldl (""),
183     # then adds it and tries again.
184     # Before each attempt the search cache must be unset,
185     # otherwise autoconf will stick with the old result
186
187     found=false
188     save_LIBS=$LIBS
189     for extras in "" "-ldl"; do
190         LIBS="$DPDK_LIB $extras $save_LIBS"
191         AC_LINK_IFELSE(
192            [AC_LANG_PROGRAM([#include <rte_config.h>
193                              #include <rte_eal.h>],
194                             [int rte_argc; char ** rte_argv;
195                              rte_eal_init(rte_argc, rte_argv);])],
196            [found=true])
197         if $found; then
198             break
199         fi
200     done
201     if $found; then :; else
202         AC_MSG_ERROR([cannot link with dpdk])
203     fi
204     CFLAGS="$ovs_save_CFLAGS"
205     LDFLAGS="$ovs_save_LDFLAGS"
206     OVS_LDFLAGS="$OVS_LDFLAGS -L$DPDK_LIB_DIR"
207     OVS_CFLAGS="$OVS_CFLAGS -I$DPDK_INCLUDE"
208
209     # DPDK 1.7.0 pmd drivers are not linked unless --whole-archive is used.
210     #
211     # This happens because the rest of the DPDK code doesn't use any symbol in
212     # the pmd driver objects, and the drivers register themselves using an
213     # __attribute__((constructor)) function.
214     #
215     # These options are specified inside a single -Wl directive to prevent
216     # autotools from reordering them.
217     DPDK_vswitchd_LDFLAGS=-Wl,--whole-archive,$DPDK_LIB,--no-whole-archive
218     AC_SUBST([DPDK_vswitchd_LDFLAGS])
219     AC_DEFINE([DPDK_NETDEV], [1], [System uses the DPDK module.])
220   else
221     RTE_SDK=
222   fi
223
224   AM_CONDITIONAL([DPDK_NETDEV], test -n "$RTE_SDK")
225 ])
226
227 dnl OVS_GREP_IFELSE(FILE, REGEX, [IF-MATCH], [IF-NO-MATCH])
228 dnl
229 dnl Greps FILE for REGEX.  If it matches, runs IF-MATCH, otherwise IF-NO-MATCH.
230 dnl If IF-MATCH is empty then it defines to OVS_DEFINE(HAVE_<REGEX>), with
231 dnl <REGEX> translated to uppercase.
232 AC_DEFUN([OVS_GREP_IFELSE], [
233   AC_MSG_CHECKING([whether $2 matches in $1])
234   if test -f $1; then
235     grep '$2' $1 >/dev/null 2>&1
236     status=$?
237     case $status in
238       0) 
239         AC_MSG_RESULT([yes])
240         m4_if([$3], [], [OVS_DEFINE([HAVE_]m4_toupper([$2]))], [$3])
241         ;;
242       1) 
243         AC_MSG_RESULT([no])
244         $4
245         ;;
246       *) 
247         AC_MSG_ERROR([grep exited with status $status])
248         ;;
249     esac
250   else
251     AC_MSG_RESULT([file not found])
252     $4
253   fi
254 ])
255
256 dnl OVS_DEFINE(NAME)
257 dnl
258 dnl Defines NAME to 1 in kcompat.h.
259 AC_DEFUN([OVS_DEFINE], [
260   echo '#define $1 1' >> datapath/linux/kcompat.h.new
261 ])
262
263 AC_DEFUN([OVS_CHECK_LOG2_H], [
264   AC_MSG_CHECKING([for $KSRC/include/linux/log2.h])
265   if test -e $KSRC/include/linux/log2.h; then
266     AC_MSG_RESULT([yes])
267     OVS_DEFINE([HAVE_LOG2_H])
268   else
269     AC_MSG_RESULT([no])
270   fi
271 ])
272
273 dnl OVS_CHECK_LINUX_COMPAT
274 dnl
275 dnl Runs various Autoconf checks on the Linux 2.6 kernel source in
276 dnl the directory in $KBUILD.
277 AC_DEFUN([OVS_CHECK_LINUX_COMPAT], [
278   rm -f datapath/linux/kcompat.h.new
279   mkdir -p datapath/linux
280   : > datapath/linux/kcompat.h.new
281
282   OVS_GREP_IFELSE([$KSRC/arch/x86/include/asm/checksum_32.h], [src_err,],
283                   [OVS_DEFINE([HAVE_CSUM_COPY_DBG])])
284
285   OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [ERR_CAST])
286   OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [IS_ERR_OR_NULL])
287
288   OVS_GREP_IFELSE([$KSRC/include/linux/etherdevice.h], [eth_hw_addr_random])
289   OVS_GREP_IFELSE([$KSRC/include/linux/etherdevice.h], [ether_addr_copy])
290
291   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_set_encap_proto])
292
293   OVS_GREP_IFELSE([$KSRC/include/linux/in.h], [ipv4_is_multicast])
294   OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [__ip_select_ident.*dst_entry],
295                   [OVS_DEFINE([HAVE_IP_SELECT_IDENT_USING_DST_ENTRY])])
296
297   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_disable_lro])
298   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_stats])
299   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_by_index_rcu])
300   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [__skb_gso_segment])
301   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [can_checksum_protocol])
302   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [netdev_features_t])
303   OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [pcpu_sw_netstats])
304
305   OVS_GREP_IFELSE([$KSRC/include/linux/random.h], [prandom_u32])
306
307   OVS_GREP_IFELSE([$KSRC/include/linux/rcupdate.h], [rcu_read_lock_held], [],
308                   [OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h],
309                                    [rcu_read_lock_held])])
310   OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h], [lockdep_rtnl_is_held])
311   
312   # Check for the proto_data_valid member in struct sk_buff.  The [^@]
313   # is necessary because some versions of this header remove the
314   # member but retain the kerneldoc comment that describes it (which
315   # starts with @).  The brackets must be doubled because of m4
316   # quoting rules.
317   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [[[^@]]proto_data_valid],
318                   [OVS_DEFINE([HAVE_PROTO_DATA_VALID])])
319   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [rxhash])
320   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [u16.*rxhash],
321                   [OVS_DEFINE([HAVE_U16_RXHASH])])
322   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_dst(],
323                   [OVS_DEFINE([HAVE_SKB_DST_ACCESSOR_FUNCS])])
324   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], 
325                   [skb_copy_from_linear_data_offset])
326   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
327                   [skb_reset_tail_pointer])
328   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_cow_head])
329   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_transport_header],
330                   [OVS_DEFINE([HAVE_SKBUFF_HEADER_HELPERS])])
331   OVS_GREP_IFELSE([$KSRC/include/linux/icmpv6.h], [icmp6_hdr],
332                   [OVS_DEFINE([HAVE_ICMP6_HDR])])
333   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_warn_if_lro],
334                   [OVS_DEFINE([HAVE_SKB_WARN_LRO])])
335   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [consume_skb])
336   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_frag_page])
337   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_has_frag_list])
338   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [__skb_fill_page_desc])
339   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_reset_mac_len])
340   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_unclone])
341   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_orphan_frags])
342   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_get_hash])
343   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_clear_hash])
344   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [l4_rxhash])
345
346   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [bool],
347                   [OVS_DEFINE([HAVE_BOOL_TYPE])])
348   OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [__wsum],
349                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
350   OVS_GREP_IFELSE([$KSRC/include/uapi/linux/types.h], [__wsum],
351                   [OVS_DEFINE([HAVE_CSUM_TYPES])])
352
353   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_replace4])
354   OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_unfold])
355
356   OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [parallel_ops])
357   OVS_GREP_IFELSE([$KSRC/include/net/gre.h], [gre_cisco_register])
358   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_get_be16])
359   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be16])
360   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be32])
361   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be64])
362   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_find_nested])
363
364   OVS_GREP_IFELSE([$KSRC/include/net/sctp/checksum.h], [sctp_compute_cksum])
365
366   OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [ADD_ALL_VLANS_CMD],
367                   [OVS_DEFINE([HAVE_VLAN_BUG_WORKAROUND])])
368
369   OVS_GREP_IFELSE([$KSRC/include/linux/u64_stats_sync.h], [u64_stats_fetch_begin_irq])
370
371   OVS_GREP_IFELSE([$KSRC/include/linux/openvswitch.h], [openvswitch_handle_frame_hook],
372                   [OVS_DEFINE([HAVE_RHEL_OVS_HOOK])])
373   OVS_GREP_IFELSE([$KSRC/include/net/vxlan.h], [bool xnet],
374                   [OVS_DEFINE([HAVE_VXLAN_XMIT_SKB_XNET_ARG])])
375   OVS_GREP_IFELSE([$KSRC/include/net/udp.h], [udp_flow_src_port],
376                   [OVS_DEFINE([HAVE_UDP_FLOW_SRC_PORT])])
377   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [ignore_df:1],
378                   [OVS_DEFINE([HAVE_IGNORE_DF_RENAME])])
379   OVS_GREP_IFELSE([$KSRC/include/uapi/linux/netdevice.h], [NET_NAME_UNKNOWN],
380                   [OVS_DEFINE([HAVE_NET_NAME_UNKNOWN])])
381
382   OVS_CHECK_LOG2_H
383
384   if cmp -s datapath/linux/kcompat.h.new \
385             datapath/linux/kcompat.h >/dev/null 2>&1; then
386     rm datapath/linux/kcompat.h.new
387   else
388     mv datapath/linux/kcompat.h.new datapath/linux/kcompat.h
389   fi
390 ])
391
392 dnl Checks for net/if_packet.h.
393 AC_DEFUN([OVS_CHECK_IF_PACKET],
394   [AC_CHECK_HEADER([net/if_packet.h],
395                    [HAVE_IF_PACKET=yes],
396                    [HAVE_IF_PACKET=no])
397    AM_CONDITIONAL([HAVE_IF_PACKET], [test "$HAVE_IF_PACKET" = yes])
398    if test "$HAVE_IF_PACKET" = yes; then
399       AC_DEFINE([HAVE_IF_PACKET], [1],
400                 [Define to 1 if net/if_packet.h is available.])
401    fi])
402
403 dnl Checks for net/if_dl.h.
404 dnl
405 dnl (We use this as a proxy for checking whether we're building on FreeBSD
406 dnl or NetBSD.)
407 AC_DEFUN([OVS_CHECK_IF_DL],
408   [AC_CHECK_HEADER([net/if_dl.h],
409                    [HAVE_IF_DL=yes],
410                    [HAVE_IF_DL=no])
411    AM_CONDITIONAL([HAVE_IF_DL], [test "$HAVE_IF_DL" = yes])
412    if test "$HAVE_IF_DL" = yes; then
413       AC_DEFINE([HAVE_IF_DL], [1],
414                 [Define to 1 if net/if_dl.h is available.])
415
416       # On these platforms we use libpcap to access network devices.
417       AC_SEARCH_LIBS([pcap_open_live], [pcap])
418    fi])
419
420 dnl Checks for buggy strtok_r.
421 dnl
422 dnl Some versions of glibc 2.7 has a bug in strtok_r when compiling
423 dnl with optimization that can cause segfaults:
424 dnl
425 dnl http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
426 AC_DEFUN([OVS_CHECK_STRTOK_R],
427   [AC_CACHE_CHECK(
428      [whether strtok_r macro segfaults on some inputs],
429      [ovs_cv_strtok_r_bug],
430      [AC_RUN_IFELSE(
431         [AC_LANG_PROGRAM([#include <stdio.h>
432                           #include <string.h>
433                          ],
434                          [[char string[] = ":::";
435                            char *save_ptr = (char *) 0xc0ffee;
436                            char *token1, *token2;
437                            token1 = strtok_r(string, ":", &save_ptr);
438                            token2 = strtok_r(NULL, ":", &save_ptr);
439                            freopen ("/dev/null", "w", stdout);
440                            printf ("%s %s\n", token1, token2);
441                            return 0;
442                           ]])],
443         [ovs_cv_strtok_r_bug=no],
444         [ovs_cv_strtok_r_bug=yes],
445         [ovs_cv_strtok_r_bug=yes])])
446    if test $ovs_cv_strtok_r_bug = yes; then
447      AC_DEFINE([HAVE_STRTOK_R_BUG], [1],
448                [Define if strtok_r macro segfaults on some inputs])
449    fi
450 ])
451
452 dnl ----------------------------------------------------------------------
453 dnl These macros are from GNU PSPP, with the following original license:
454 dnl Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
455 dnl This file is free software; the Free Software Foundation
456 dnl gives unlimited permission to copy and/or distribute it,
457 dnl with or without modifications, as long as this notice is preserved.
458
459 AC_DEFUN([_OVS_CHECK_CC_OPTION], [dnl
460   m4_define([ovs_cv_name], [ovs_cv_[]m4_translit([$1], [-=], [__])])dnl
461   AC_CACHE_CHECK([whether $CC accepts $1], [ovs_cv_name], 
462     [ovs_save_CFLAGS="$CFLAGS"
463      dnl Include -Werror in the compiler options, because without -Werror
464      dnl clang's GCC-compatible compiler driver does not return a failure
465      dnl exit status even though it complains about options it does not
466      dnl understand.
467      CFLAGS="$CFLAGS $WERROR $1"
468      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [ovs_cv_name[]=yes], [ovs_cv_name[]=no])
469      CFLAGS="$ovs_save_CFLAGS"])
470   if test $ovs_cv_name = yes; then
471     m4_if([$2], [], [:], [$2])
472   else
473     m4_if([$3], [], [:], [$3])
474   fi
475 ])
476
477 dnl OVS_CHECK_WERROR
478 dnl
479 dnl Check whether the C compiler accepts -Werror.
480 dnl Sets $WERROR to "-Werror", if so, and otherwise to the empty string.
481 AC_DEFUN([OVS_CHECK_WERROR],
482   [WERROR=
483    _OVS_CHECK_CC_OPTION([-Werror], [WERROR=-Werror])])
484
485 dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
486 dnl Check whether the given C compiler OPTION is accepted.
487 dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
488 AC_DEFUN([OVS_CHECK_CC_OPTION],
489   [AC_REQUIRE([OVS_CHECK_WERROR])
490    _OVS_CHECK_CC_OPTION([$1], [$2], [$3])])
491
492 dnl OVS_ENABLE_OPTION([OPTION])
493 dnl Check whether the given C compiler OPTION is accepted.
494 dnl If so, add it to WARNING_FLAGS.
495 dnl Example: OVS_ENABLE_OPTION([-Wdeclaration-after-statement])
496 AC_DEFUN([OVS_ENABLE_OPTION], 
497   [OVS_CHECK_CC_OPTION([$1], [WARNING_FLAGS="$WARNING_FLAGS $1"])
498    AC_SUBST([WARNING_FLAGS])])
499
500 dnl OVS_CONDITIONAL_CC_OPTION([OPTION], [CONDITIONAL])
501 dnl Check whether the given C compiler OPTION is accepted.
502 dnl If so, enable the given Automake CONDITIONAL.
503
504 dnl Example: OVS_CONDITIONAL_CC_OPTION([-Wno-unused], [HAVE_WNO_UNUSED])
505 AC_DEFUN([OVS_CONDITIONAL_CC_OPTION],
506   [OVS_CHECK_CC_OPTION(
507     [$1], [ovs_have_cc_option=yes], [ovs_have_cc_option=no])
508    AM_CONDITIONAL([$2], [test $ovs_have_cc_option = yes])])
509 dnl ----------------------------------------------------------------------
510
511 dnl Check for too-old XenServer.
512 AC_DEFUN([OVS_CHECK_XENSERVER_VERSION],
513   [AC_CACHE_CHECK([XenServer release], [ovs_cv_xsversion],
514     [if test -e /etc/redhat-release; then
515        ovs_cv_xsversion=`sed -n 's/^XenServer DDK release \([[^-]]*\)-.*/\1/p' /etc/redhat-release`
516      fi
517      if test -z "$ovs_cv_xsversion"; then
518        ovs_cv_xsversion=none
519      fi])
520   case $ovs_cv_xsversion in
521     none)
522       ;;
523
524     [[1-9]][[0-9]]* |                    dnl XenServer 10 or later
525     [[6-9]]* |                           dnl XenServer 6 or later
526     5.[[7-9]]* |                         dnl XenServer 5.7 or later
527     5.6.[[1-9]][[0-9]][[0-9]][[0-9]]* |  dnl XenServer 5.6.1000 or later
528     5.6.[[2-9]][[0-9]][[0-9]]* |         dnl XenServer 5.6.200 or later
529     5.6.1[[0-9]][[0-9]])                 dnl Xenserver 5.6.100 or later
530       ;;
531
532     *)
533       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.)])
534       ;;
535   esac])
536
537 dnl OVS_MAKE_HAS_IF([if-true], [if-false])
538 dnl
539 dnl Checks whether make has the GNU make $(if condition,then,else) extension.
540 dnl Runs 'if-true' if so, 'if-false' otherwise.
541 AC_DEFUN([OVS_CHECK_MAKE_IF],
542   [AC_CACHE_CHECK(
543      [whether ${MAKE-make} has GNU make \$(if) extension],
544      [ovs_cv_gnu_make_if],
545      [cat <<'EOF' > conftest.mk
546 conftest.out:
547         echo $(if x,y,z) > conftest.out
548 .PHONY: all
549 EOF
550       rm -f conftest.out
551       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} -f conftest.mk all:"]) >&AS_MESSAGE_LOG_FD 2>&1
552       ${MAKE-make} -f conftest.mk conftest.out >&AS_MESSAGE_LOG_FD 2>&1
553       AS_ECHO(["$as_me:$LINENO: conftest.out contains:"]) >&AS_MESSAGE_LOG_FD 2>&1
554       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
555       result=`cat conftest.out`
556       rm -f conftest.mk conftest.out
557       if test "X$result" = "Xy"; then
558         ovs_cv_gnu_make_if=yes
559       else
560         ovs_cv_gnu_make_if=no
561       fi])])
562
563 dnl OVS_CHECK_GNU_MAKE
564 dnl
565 dnl Checks whether make is GNU make (because Linux kernel Makefiles
566 dnl only work with GNU make).
567 AC_DEFUN([OVS_CHECK_GNU_MAKE],
568   [AC_CACHE_CHECK(
569      [whether ${MAKE-make} is GNU make],
570      [ovs_cv_gnu_make],
571      [rm -f conftest.out
572       AS_ECHO(["$as_me:$LINENO: invoking ${MAKE-make} --version:"]) >&AS_MESSAGE_LOG_FD 2>&1
573       ${MAKE-make} --version >conftest.out 2>&1
574       cat conftest.out >&AS_MESSAGE_LOG_FD 2>&1
575       result=`cat conftest.out`
576       rm -f conftest.mk conftest.out
577
578       case $result in # (
579         GNU*) ovs_cv_gnu_make=yes ;; # (
580         *) ovs_cv_gnu_make=no ;;
581       esac])
582    AM_CONDITIONAL([GNU_MAKE], [test $ovs_cv_gnu_make = yes])])
583
584 dnl OVS_CHECK_SPARSE_TARGET
585 dnl
586 dnl The "cgcc" script from "sparse" isn't very good at detecting the
587 dnl target for which the code is being built.  This helps it out.
588 AC_DEFUN([OVS_CHECK_SPARSE_TARGET],
589   [AC_CACHE_CHECK(
590     [target hint for cgcc],
591     [ac_cv_sparse_target],
592     [AS_CASE([`$CC -dumpmachine 2>/dev/null`],
593        [i?86-* | athlon-*], [ac_cv_sparse_target=x86],
594        [x86_64-*], [ac_cv_sparse_target=x86_64],
595        [ac_cv_sparse_target=other])])
596    AS_CASE([$ac_cv_sparse_target],
597      [x86], [SPARSEFLAGS= CGCCFLAGS=-target=i86],
598      [x86_64], [SPARSEFLAGS=-m64 CGCCFLAGS=-target=x86_64],
599      [SPARSEFLAGS= CGCCFLAGS=])
600    AC_SUBST([SPARSEFLAGS])
601    AC_SUBST([CGCCFLAGS])])
602
603 dnl OVS_SPARSE_EXTRA_INCLUDES
604 dnl
605 dnl The cgcc script from "sparse" does not search gcc's default
606 dnl search path. Get the default search path from GCC and pass
607 dnl them to sparse.
608 AC_DEFUN([OVS_SPARSE_EXTRA_INCLUDES],
609     AC_SUBST([SPARSE_EXTRA_INCLUDES],
610            [`$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 ' ' `] ))
611
612 dnl OVS_ENABLE_SPARSE
613 AC_DEFUN([OVS_ENABLE_SPARSE],
614   [AC_REQUIRE([OVS_CHECK_SPARSE_TARGET])
615    AC_REQUIRE([OVS_CHECK_MAKE_IF])
616    AC_REQUIRE([OVS_SPARSE_EXTRA_INCLUDES])
617    : ${SPARSE=sparse}
618    AC_SUBST([SPARSE])
619    AC_CONFIG_COMMANDS_PRE(
620      [if test $ovs_cv_gnu_make_if = yes; then
621         CC='$(if $(C),env REAL_CC="'"$CC"'" CHECK="$(SPARSE) -I $(top_srcdir)/include/sparse $(SPARSEFLAGS) $(SPARSE_EXTRA_INCLUDES) " cgcc $(CGCCFLAGS),'"$CC"')'
622       fi])])
623
624 dnl OVS_PTHREAD_SET_NAME
625 dnl
626 dnl This checks for three known variants of pthreads functions for setting
627 dnl the name of the current thread:
628 dnl
629 dnl   glibc: int pthread_setname_np(pthread_t, const char *name);
630 dnl   NetBSD: int pthread_setname_np(pthread_t, const char *format, void *arg);
631 dnl   FreeBSD: int pthread_set_name_np(pthread_t, const char *name);
632 dnl
633 dnl For glibc and FreeBSD, the arguments are just a thread and its name.  For
634 dnl NetBSD, 'format' is a printf() format string and 'arg' is an argument to
635 dnl provide to it.
636 dnl
637 dnl This macro defines:
638 dnl
639 dnl    glibc: HAVE_GLIBC_PTHREAD_SETNAME_NP
640 dnl    NetBSD: HAVE_NETBSD_PTHREAD_SETNAME_NP
641 dnl    FreeBSD: HAVE_PTHREAD_SET_NAME_NP
642 AC_DEFUN([OVS_CHECK_PTHREAD_SET_NAME],
643   [AC_CHECK_FUNCS([pthread_set_name_np])
644    if test $ac_cv_func_pthread_set_name_np != yes; then
645      AC_CACHE_CHECK(
646        [for pthread_setname_np() variant],
647        [ovs_cv_pthread_setname_np],
648        [AC_LINK_IFELSE(
649          [AC_LANG_PROGRAM([#include <pthread.h>
650   ], [pthread_setname_np(pthread_self(), "name");])],
651          [ovs_cv_pthread_setname_np=glibc],
652          [AC_LINK_IFELSE(
653            [AC_LANG_PROGRAM([#include <pthread.h>
654 ], [pthread_setname_np(pthread_self(), "%s", "name");])],
655            [ovs_cv_pthread_setname_np=netbsd],
656            [ovs_cv_pthread_setname_np=none])])])
657      case $ovs_cv_pthread_setname_np in # (
658        glibc)
659           AC_DEFINE(
660             [HAVE_GLIBC_PTHREAD_SETNAME_NP], [1],
661             [Define to 1 if pthread_setname_np() is available and takes 2 parameters (like glibc).])
662           ;; # (
663        netbsd)
664           AC_DEFINE(
665             [HAVE_NETBSD_PTHREAD_SETNAME_NP], [1],
666             [Define to 1 if pthread_setname_np() is available and takes 3 parameters (like NetBSD).])
667           ;;
668      esac
669    fi])
670
671 dnl OVS_CHECK_LINUX_HOST.
672 dnl
673 dnl Checks whether we're building for a Linux host, based on the presence of
674 dnl the __linux__ preprocessor symbol, and sets up an Automake conditional
675 dnl LINUX based on the result.
676 AC_DEFUN([OVS_CHECK_LINUX_HOST],
677   [AC_CACHE_CHECK(
678      [whether __linux__ is defined],
679      [ovs_cv_linux],
680      [AC_COMPILE_IFELSE(
681         [AC_LANG_PROGRAM([enum { LINUX = __linux__};], [])],
682         [ovs_cv_linux=true],
683         [ovs_cv_linux=false])])
684    AM_CONDITIONAL([LINUX], [$ovs_cv_linux])])