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openvswitch.m4
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# -*- autoconf -*-
# Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
dnl Checks for --enable-coverage and updates CFLAGS and LDFLAGS appropriately.
AC_DEFUN([OVS_CHECK_COVERAGE],
[AC_REQUIRE([AC_PROG_CC])
AC_ARG_ENABLE(
[coverage],
[AC_HELP_STRING([--enable-coverage],
[Enable gcov coverage tool.])],
[case "${enableval}" in
(yes) coverage=true ;;
(no) coverage=false ;;
(*) AC_MSG_ERROR([bad value ${enableval} for --enable-coverage]) ;;
esac],
[coverage=false])
if $coverage; then
CFLAGS="$CFLAGS -O0 --coverage"
LDFLAGS="$LDFLAGS --coverage"
fi])
dnl Checks for --enable-ndebug and defines NDEBUG if it is specified.
AC_DEFUN([OVS_CHECK_NDEBUG],
[AC_ARG_ENABLE(
[ndebug],
[AC_HELP_STRING([--enable-ndebug],
[Disable debugging features for max performance])],
[case "${enableval}" in
(yes) ndebug=true ;;
(no) ndebug=false ;;
(*) AC_MSG_ERROR([bad value ${enableval} for --enable-ndebug]) ;;
esac],
[ndebug=false])
AM_CONDITIONAL([NDEBUG], [test x$ndebug = xtrue])])
dnl Checks for ESX.
AC_DEFUN([OVS_CHECK_ESX],
[AC_CHECK_HEADER([vmware.h],
[ESX=yes],
[ESX=no])
AM_CONDITIONAL([ESX], [test "$ESX" = yes])
if test "$ESX" = yes; then
AC_DEFINE([ESX], [1], [Define to 1 if building on ESX.])
fi])
dnl Checks for WINDOWS.
AC_DEFUN([OVS_CHECK_WIN32],
[AC_CHECK_HEADER([windows.h],
[WIN32=yes],
[WIN32=no])
AM_CONDITIONAL([WIN32], [test "$WIN32" = yes])
if test "$WIN32" = yes; then
AC_DEFINE([WIN32], [1], [Define to 1 if building on WIN32.])
fi])
dnl Checks for Netlink support.
AC_DEFUN([OVS_CHECK_NETLINK],
[AC_CHECK_HEADER([linux/netlink.h],
[HAVE_NETLINK=yes],
[HAVE_NETLINK=no],
[#include <sys/socket.h>
#include <linux/types.h>
])
AM_CONDITIONAL([HAVE_NETLINK], [test "$HAVE_NETLINK" = yes])
if test "$HAVE_NETLINK" = yes; then
AC_DEFINE([HAVE_NETLINK], [1],
[Define to 1 if Netlink protocol is available.])
fi])
dnl Checks for OpenSSL.
AC_DEFUN([OVS_CHECK_OPENSSL],
[AC_ARG_ENABLE(
[ssl],
[AC_HELP_STRING([--disable-ssl], [Disable OpenSSL support])],
[case "${enableval}" in
(yes) ssl=true ;;
(no) ssl=false ;;
(*) AC_MSG_ERROR([bad value ${enableval} for --enable-ssl]) ;;
esac],
[ssl=check])
if test "$ssl" != false; then
AX_CHECK_OPENSSL(
[HAVE_OPENSSL=yes],
[HAVE_OPENSSL=no
if test "$ssl" = check; then
AC_MSG_WARN([Cannot find openssl:
$SSL_PKG_ERRORS
OpenFlow connections over SSL will not be supported.
(You may use --disable-ssl to suppress this warning.)])
else
AC_MSG_ERROR([Cannot find openssl (use --disable-ssl to configure without SSL support)])
fi])
else
HAVE_OPENSSL=no
fi
AC_SUBST([HAVE_OPENSSL])
AM_CONDITIONAL([HAVE_OPENSSL], [test "$HAVE_OPENSSL" = yes])
if test "$HAVE_OPENSSL" = yes; then
AC_DEFINE([HAVE_OPENSSL], [1], [Define to 1 if OpenSSL is installed.])
fi])
dnl Checks for libraries needed by lib/socket-util.c.
AC_DEFUN([OVS_CHECK_SOCKET_LIBS],
[AC_CHECK_LIB([socket], [connect])
AC_SEARCH_LIBS([gethostbyname], [resolv])])
dnl Checks for the directory in which to store the PKI.
AC_DEFUN([OVS_CHECK_PKIDIR],
[AC_ARG_WITH(
[pkidir],
AC_HELP_STRING([--with-pkidir=DIR],
[PKI hierarchy directory [[LOCALSTATEDIR/lib/openvswitch/pki]]]),
[PKIDIR=$withval],
[PKIDIR='${localstatedir}/lib/openvswitch/pki'])
AC_SUBST([PKIDIR])])
dnl Checks for the directory in which to store pidfiles.
AC_DEFUN([OVS_CHECK_RUNDIR],
[AC_ARG_WITH(
[rundir],
AC_HELP_STRING([--with-rundir=DIR],
[directory used for pidfiles
[[LOCALSTATEDIR/run/openvswitch]]]),
[RUNDIR=$withval],
[RUNDIR='${localstatedir}/run/openvswitch'])
AC_SUBST([RUNDIR])])
dnl Checks for the directory in which to store logs.
AC_DEFUN([OVS_CHECK_LOGDIR],
[AC_ARG_WITH(
[logdir],
AC_HELP_STRING([--with-logdir=DIR],
[directory used for logs [[LOCALSTATEDIR/log/PACKAGE]]]),
[LOGDIR=$withval],
[LOGDIR='${localstatedir}/log/${PACKAGE}'])
AC_SUBST([LOGDIR])])
dnl Checks for the directory in which to store the Open vSwitch database.
AC_DEFUN([OVS_CHECK_DBDIR],
[AC_ARG_WITH(
[dbdir],
AC_HELP_STRING([--with-dbdir=DIR],
[directory used for conf.db [[SYSCONFDIR/PACKAGE]]]),
[DBDIR=$withval],
[DBDIR='${sysconfdir}/${PACKAGE}'])
AC_SUBST([DBDIR])])
dnl Defines HAVE_BACKTRACE if backtrace() is found.
AC_DEFUN([OVS_CHECK_BACKTRACE],
[AC_SEARCH_LIBS([backtrace], [execinfo ubacktrace],
[AC_DEFINE([HAVE_BACKTRACE], [1],
[Define to 1 if you have backtrace(3).])])])
dnl Checks for __malloc_hook, etc., supported by glibc.
AC_DEFUN([OVS_CHECK_MALLOC_HOOKS],
[AC_CACHE_CHECK(
[whether libc supports hooks for malloc and related functions],
[ovs_cv_malloc_hooks],
[AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM(
[#include <malloc.h>
],
[(void) __malloc_hook;
(void) __realloc_hook;
(void) __free_hook;])],
[ovs_cv_malloc_hooks=yes],
[ovs_cv_malloc_hooks=no])])
if test $ovs_cv_malloc_hooks = yes; then
AC_DEFINE([HAVE_MALLOC_HOOKS], [1],
[Define to 1 if you have __malloc_hook, __realloc_hook, and
__free_hook in <malloc.h>.])
fi])
dnl Checks for valgrind/valgrind.h.
AC_DEFUN([OVS_CHECK_VALGRIND],
[AC_CHECK_HEADERS([valgrind/valgrind.h])])
dnl Checks for Python 2.x, x >= 4.
AC_DEFUN([OVS_CHECK_PYTHON],
[AC_CACHE_CHECK(
[for Python 2.x for x >= 4],
[ovs_cv_python],
[if test -n "$PYTHON"; then
ovs_cv_python=$PYTHON
else
ovs_cv_python=no
for binary in python python2.4 python2.5; do
ovs_save_IFS=$IFS; IFS=$PATH_SEPARATOR
for dir in $PATH; do
IFS=$ovs_save_IFS
test -z "$dir" && dir=.
if test -x "$dir"/"$binary" && "$dir"/"$binary" -c 'import sys
if sys.hexversion >= 0x02040000 and sys.hexversion < 0x03000000:
sys.exit(0)
else:
sys.exit(1)'; then
ovs_cv_python=$dir/$binary
break 2
fi
done
done
fi])
AC_SUBST([HAVE_PYTHON])
AM_MISSING_PROG([PYTHON], [python])
if test $ovs_cv_python != no; then
PYTHON=$ovs_cv_python
HAVE_PYTHON=yes
else
HAVE_PYTHON=no
fi
AM_CONDITIONAL([HAVE_PYTHON], [test "$HAVE_PYTHON" = yes])])
dnl Checks for dot.
AC_DEFUN([OVS_CHECK_DOT],
[AC_CACHE_CHECK(
[for dot],
[ovs_cv_dot],
[dnl "dot" writes -V output to stderr:
if (dot -V) 2>&1 | grep '^dot - [[gG]]raphviz version' >/dev/null 2>&1; then
ovs_cv_dot=yes
else
ovs_cv_dot=no
fi])
AM_CONDITIONAL([HAVE_DOT], [test "$ovs_cv_dot" = yes])])
dnl Checks for pyuic4.
AC_DEFUN([OVS_CHECK_PYUIC4],
[AC_CACHE_CHECK(
[for pyuic4],
[ovs_cv_pyuic4],
[if (pyuic4 --version) >/dev/null 2>&1; then
ovs_cv_pyuic4=pyuic4
else
ovs_cv_pyuic4=no
fi])
AM_MISSING_PROG([PYUIC4], [pyuic4])
if test $ovs_cv_pyuic4 != no; then
PYUIC4=$ovs_cv_pyuic4
fi])
dnl Checks whether $PYTHON supports the module given as $1
AC_DEFUN([OVS_CHECK_PYTHON_MODULE],
[AC_REQUIRE([OVS_CHECK_PYTHON])
AC_CACHE_CHECK(
[for $1 Python module],
[ovs_cv_py_[]AS_TR_SH([$1])],
[ovs_cv_py_[]AS_TR_SH([$1])=no
if test $HAVE_PYTHON = yes; then
AS_ECHO(["running $PYTHON -c 'import $1
import sys
sys.exit(0)'..."]) >&AS_MESSAGE_LOG_FD 2>&1
if $PYTHON -c 'import $1
import sys
sys.exit(0)' >&AS_MESSAGE_LOG_FD 2>&1; then
ovs_cv_py_[]AS_TR_SH([$1])=yes
fi
fi])])
dnl Checks for Python modules needed by ovsdbmonitor.
AC_DEFUN([OVS_CHECK_OVSDBMONITOR],
[OVS_CHECK_PYTHON_MODULE([PySide.QtCore])
OVS_CHECK_PYTHON_MODULE([PyQt4.QtCore])
OVS_CHECK_PYTHON_MODULE([twisted.conch.ssh])
OVS_CHECK_PYTHON_MODULE([twisted.internet])
OVS_CHECK_PYTHON_MODULE([twisted.application])
OVS_CHECK_PYTHON_MODULE([json])
OVS_CHECK_PYTHON_MODULE([zope.interface])
if (test $ovs_cv_py_PySide_QtCore = yes \
|| test $ovs_cv_py_PyQt4_QtCore = yes) \
&& test $ovs_cv_py_twisted_conch_ssh = yes \
&& test $ovs_cv_py_twisted_internet = yes \
&& test $ovs_cv_py_twisted_application = yes \
&& test $ovs_cv_py_json = yes \
&& test $ovs_cv_py_zope_interface = yes; then
BUILD_OVSDBMONITOR=yes
else
BUILD_OVSDBMONITOR=no
fi
AC_MSG_CHECKING([whether to build ovsdbmonitor])
AC_MSG_RESULT([$BUILD_OVSDBMONITOR])
AM_CONDITIONAL([BUILD_OVSDBMONITOR], [test $BUILD_OVSDBMONITOR = yes])])
dnl Checks for missing python modules at build time
AC_DEFUN([OVS_CHECK_PYTHON_COMPAT],
[OVS_CHECK_PYTHON_MODULE([uuid])
if test $ovs_cv_py_uuid = yes; then
INCLUDE_PYTHON_COMPAT=no
else
INCLUDE_PYTHON_COMPAT=yes
fi
AC_MSG_CHECKING([whether to add python/compat to PYTHONPATH])
AC_MSG_RESULT([$INCLUDE_PYTHON_COMPAT])
AM_CONDITIONAL([INCLUDE_PYTHON_COMPAT], [test $INCLUDE_PYTHON_COMPAT = yes])])
# OVS_LINK2_IFELSE(SOURCE1, SOURCE2, [ACTION-IF-TRUE], [ACTION-IF-FALSE])
# -------------------------------------------------------------
# Based on AC_LINK_IFELSE, but tries to link both SOURCE1 and SOURCE2
# into a program.
#
# This macro is borrowed from acinclude.m4 in GNU PSPP, which has the
# following license:
#
# Copyright (C) 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
#
m4_define([OVS_LINK2_IFELSE],
[m4_ifvaln([$1], [AC_LANG_CONFTEST([$1])])dnl
mv conftest.$ac_ext conftest1.$ac_ext
m4_ifvaln([$2], [AC_LANG_CONFTEST([$2])])dnl
mv conftest.$ac_ext conftest2.$ac_ext
rm -f conftest1.$ac_objext conftest2.$ac_objext conftest$ac_exeext
ovs_link2='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest1.$ac_ext conftest2.$ac_ext $LIBS >&5'
AS_IF([_AC_DO_STDERR($ovs_link2) && {
test -z "$ac_[]_AC_LANG_ABBREV[]_werror_flag" ||
test ! -s conftest.err
} && test -s conftest$ac_exeext && {
test "$cross_compiling" = yes ||
AS_TEST_X([conftest$ac_exeext])
}],
[$3],
[echo "$as_me: failed source file 1 of 2 was:" >&5
sed 's/^/| /' conftest1.$ac_ext >&5
echo "$as_me: failed source file 2 of 2 was:" >&5
sed 's/^/| /' conftest2.$ac_ext >&5
$4])
dnl Delete also the IPA/IPO (Inter Procedural Analysis/Optimization)
dnl information created by the PGI compiler (conftest_ipa8_conftest.oo),
dnl as it would interfere with the next link command.
rm -rf conftest.dSYM conftest1.dSYM conftest2.dSYM
rm -f core conftest.err conftest1.err conftest2.err
rm -f conftest1.$ac_objext conftest2.$ac_objext conftest*_ipa8_conftest*.oo
rm -f conftest$ac_exeext
rm -f m4_ifval([$1], [conftest1.$ac_ext]) m4_ifval([$2], [conftest1.$ac_ext])[]dnl
])# OVS_LINK2_IFELSE
dnl Defines USE_LINKER_SECTIONS to 1 if the compiler supports putting
dnl variables in sections with user-defined names and the linker
dnl automatically defines __start_SECNAME and __stop_SECNAME symbols
dnl that designate the start and end of the sections.
AC_DEFUN([OVS_CHECK_LINKER_SECTIONS],
[AC_CACHE_CHECK(
[for user-defined linker section support],
[ovs_cv_use_linker_sections],
[OVS_LINK2_IFELSE(
[AC_LANG_SOURCE(
[int a __attribute__((__section__("mysection"))) = 1;
int b __attribute__((__section__("mysection"))) = 2;
int c __attribute__((__section__("mysection"))) = 3;])],
[AC_LANG_PROGRAM(
[#include <stdio.h>
extern int __start_mysection;
extern int __stop_mysection;],
[int n_ints = &__stop_mysection - &__start_mysection;
int *i;
for (i = &__start_mysection; i < &__start_mysection + n_ints; i++) {
printf("%d\n", *i);
}])],
[ovs_cv_use_linker_sections=yes],
[ovs_cv_use_linker_sections=no])])
if test $ovs_cv_use_linker_sections = yes; then
AC_DEFINE([USE_LINKER_SECTIONS], [1],
[Define to 1 if the compiler support putting variables
into sections with user-defined names and the linker
automatically defines __start_SECNAME and __stop_SECNAME
symbols that designate the start and end of the section.])
fi
AM_CONDITIONAL(
[USE_LINKER_SECTIONS], [test $ovs_cv_use_linker_sections = yes])])
dnl Checks for groff.
AC_DEFUN([OVS_CHECK_GROFF],
[AC_CACHE_CHECK(
[for groff],
[ovs_cv_groff],
[if (groff -v) >/dev/null 2>&1; then
ovs_cv_groff=yes
else
ovs_cv_groff=no
fi])
AM_CONDITIONAL([HAVE_GROFF], [test "$ovs_cv_groff" = yes])])
dnl Checks for thread-local storage support.
dnl
dnl Checks whether the compiler and linker support the C11
dnl thread_local macro from <threads.h>, and if so defines
dnl HAVE_THREAD_LOCAL. If not, checks whether the compiler and linker
dnl support the GCC __thread extension, and if so defines
dnl HAVE___THREAD.
AC_DEFUN([OVS_CHECK_TLS],
[AC_CACHE_CHECK(
[whether $CC has <threads.h> that supports thread_local],
[ovs_cv_thread_local],
[AC_LINK_IFELSE(
[AC_LANG_PROGRAM([#include <threads.h>
static thread_local int var;], [return var;])],
[ovs_cv_thread_local=yes],
[ovs_cv_thread_local=no])])
if test $ovs_cv_thread_local = yes; then
AC_DEFINE([HAVE_THREAD_LOCAL], [1],
[Define to 1 if the C compiler and linker supports the C11
thread_local matcro defined in <threads.h>.])
else
AC_CACHE_CHECK(
[whether $CC supports __thread],
[ovs_cv___thread],
[AC_LINK_IFELSE(
[AC_LANG_PROGRAM([static __thread int var;], [return var;])],
[ovs_cv___thread=yes],
[ovs_cv___thread=no])])
if test $ovs_cv___thread = yes; then
AC_DEFINE([HAVE___THREAD], [1],
[Define to 1 if the C compiler and linker supports the
GCC __thread extenions.])
fi
fi])
dnl OVS_CHECK_ATOMIC_LIBS
dnl
dnl Check to see if -latomic is need for GCC atomic built-ins.
AC_DEFUN([OVS_CHECK_ATOMIC_LIBS],
[AC_SEARCH_LIBS([__atomic_load_8], [atomic])])
dnl OVS_CHECK_GCC4_ATOMICS
dnl
dnl Checks whether the compiler and linker support GCC 4.0+ atomic built-ins.
dnl A compile-time only check is not enough because the compiler defers
dnl unimplemented built-ins to libgcc, which sometimes also lacks
dnl implementations.
AC_DEFUN([OVS_CHECK_GCC4_ATOMICS],
[AC_CACHE_CHECK(
[whether $CC supports GCC 4.0+ atomic built-ins],
[ovs_cv_gcc4_atomics],
[AC_LINK_IFELSE(
[AC_LANG_PROGRAM([[#include <stdlib.h>
#define ovs_assert(expr) if (!(expr)) abort();
#define TEST_ATOMIC_TYPE(TYPE) \
{ \
TYPE x = 1; \
TYPE orig; \
\
__sync_synchronize(); \
ovs_assert(x == 1); \
\
__sync_synchronize(); \
x = 3; \
__sync_synchronize(); \
ovs_assert(x == 3); \
\
orig = __sync_fetch_and_add(&x, 1); \
ovs_assert(orig == 3); \
__sync_synchronize(); \
ovs_assert(x == 4); \
\
orig = __sync_fetch_and_sub(&x, 2); \
ovs_assert(orig == 4); \
__sync_synchronize(); \
ovs_assert(x == 2); \
\
orig = __sync_fetch_and_or(&x, 6); \
ovs_assert(orig == 2); \
__sync_synchronize(); \
ovs_assert(x == 6); \
\
orig = __sync_fetch_and_and(&x, 10); \
ovs_assert(orig == 6); \
__sync_synchronize(); \
ovs_assert(x == 2); \
\
orig = __sync_fetch_and_xor(&x, 10); \
ovs_assert(orig == 2); \
__sync_synchronize(); \
ovs_assert(x == 8); \
}]], [dnl
TEST_ATOMIC_TYPE(char);
TEST_ATOMIC_TYPE(unsigned char);
TEST_ATOMIC_TYPE(signed char);
TEST_ATOMIC_TYPE(short);
TEST_ATOMIC_TYPE(unsigned short);
TEST_ATOMIC_TYPE(int);
TEST_ATOMIC_TYPE(unsigned int);
TEST_ATOMIC_TYPE(long int);
TEST_ATOMIC_TYPE(unsigned long int);
TEST_ATOMIC_TYPE(long long int);
TEST_ATOMIC_TYPE(unsigned long long int);
])],
[ovs_cv_gcc4_atomics=yes],
[ovs_cv_gcc4_atomics=no])])
if test $ovs_cv_gcc4_atomics = yes; then
AC_DEFINE([HAVE_GCC4_ATOMICS], [1],
[Define to 1 if the C compiler and linker supports the GCC 4.0+
atomic built-ins.])
fi])
dnl OVS_CHECK_ATOMIC_ALWAYS_LOCK_FREE(SIZE)
dnl
dnl Checks __atomic_always_lock_free(SIZE, 0)
AC_DEFUN([OVS_CHECK_ATOMIC_ALWAYS_LOCK_FREE],
[AC_CACHE_CHECK(
[value of __atomic_always_lock_free($1)],
[ovs_cv_atomic_always_lock_free_$1],
[AC_COMPUTE_INT(
[ovs_cv_atomic_always_lock_free_$1],
[__atomic_always_lock_free($1, 0)],
[],
[ovs_cv_atomic_always_lock_free_$1=unsupported])])
if test ovs_cv_atomic_always_lock_free_$1 != unsupported; then
AC_DEFINE_UNQUOTED(
[ATOMIC_ALWAYS_LOCK_FREE_$1B],
[$ovs_cv_atomic_always_lock_free_$1],
[If the C compiler is GCC 4.7 or later, define to the return value of
__atomic_always_lock_free($1, 0). If the C compiler is not GCC or is
an older version of GCC, the value does not matter.])
fi])
dnl OVS_CHECK_POSIX_AIO
AC_DEFUN([OVS_CHECK_POSIX_AIO],
[AC_SEARCH_LIBS([aio_write], [rt])
AM_CONDITIONAL([HAVE_POSIX_AIO], [test "$ac_cv_search_aio_write" != no])])