[PATCH 1 of 5 V2] remus: add libnl3 dependency to autoconf scripts

[Shriram Rajagopalan <rshriram@cs.ubc.ca>]

# HG changeset patch
# User Shriram Rajagopalan <rshriram@cs.ubc.ca>
# Date 1377641625 25200
# Node ID cc2b88cba1c67cc0e0a00c7e63a3ba97e14609cb
# Parent  40b079bd57dea24c3b000f233ed123763483a4d5
remus: add libnl3 dependency to autoconf scripts

Libnl3 is required for controlling Remus network buffering.
This patch adds dependency on libnl3 (>= 3.2.8) to autoconf scripts.
Also provide ability to configure tools without libnl3 support, that
is without network buffering support.

Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>

diff -r 40b079bd57de -r cc2b88cba1c6 config/Tools.mk.in
--- a/config/Tools.mk.in	Sun Aug 25 14:39:36 2013 -0700
+++ b/config/Tools.mk.in	Tue Aug 27 15:13:45 2013 -0700
@@ -35,6 +35,7 @@ PTHREAD_LDFLAGS     := @PTHREAD_LDFLAGS@
 PTHREAD_LIBS        := @PTHREAD_LIBS@
 
 PTYFUNCS_LIBS       := @PTYFUNCS_LIBS@
+LIBNL3_LIBS         := @LIBNL3_LIBS@
 
 # Download GIT repositories via HTTP or GIT's own protocol?
 # GIT's protocol is faster and more robust, when it works at all (firewalls
@@ -54,6 +55,7 @@ CONFIG_QEMU_TRAD    := @qemu_traditional
 CONFIG_QEMU_XEN     := @qemu_xen@
 CONFIG_XEND         := @xend@
 CONFIG_BLKTAP1      := @blktap1@
+CONFIG_REMUS_NETBUF := @remus_netbuf@
 
 #System options
 ZLIB                := @zlib@
diff -r 40b079bd57de -r cc2b88cba1c6 tools/configure.ac
--- a/tools/configure.ac	Sun Aug 25 14:39:36 2013 -0700
+++ b/tools/configure.ac	Tue Aug 27 15:13:45 2013 -0700
@@ -208,4 +208,19 @@ AC_SUBST(libiconv)
 # Checks for header files.
 AC_CHECK_HEADERS([yajl/yajl_version.h sys/eventfd.h])
 
+# Check for libnl3 >=3.2.8. If present enable remus network buffering.
+PKG_CHECK_EXISTS([libnl-3.0 >= 3.2.8 libnl-route-3.0 >= 3.2.8 libnl-cli-3.0 >= 3.2.8],
+		[libnl3_lib="y"], [libnl3_lib="n"])
+AC_CHECK_HEADER([netlink/route/qdisc/plug.h], [libnl3_dev="y"], [libnl3_dev="n"])
+AS_IF([test "x$libnl3" = "xn" || test "x$libnl3_dev" = "xn"], [
+	    AC_MSG_WARN([Disabling support for Remus network buffering.
+	    Please install libnl3 libraries, command line tools and devel
+	    headers - version 3.2.8 or higher])
+	    AC_SUBST(remus_netbuf, [n])
+	    ],[
+	    LIBNL3_LIBS="-lnl-3 -lnl-route-3"
+	    AC_SUBST(LIBNL3_LIBS)
+	    AC_SUBST(remus_netbuf, [y])
+])
+
 AC_OUTPUT()
diff -r 40b079bd57de -r cc2b88cba1c6 tools/libxl/Makefile
--- a/tools/libxl/Makefile	Sun Aug 25 14:39:36 2013 -0700
+++ b/tools/libxl/Makefile	Tue Aug 27 15:13:45 2013 -0700
@@ -20,7 +20,7 @@ LIBUUID_LIBS += -luuid
 endif
 
 LIBXL_LIBS =
-LIBXL_LIBS = $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenstore) $(LDLIBS_libblktapctl) $(PTYFUNCS_LIBS) $(LIBUUID_LIBS)
+LIBXL_LIBS = $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenstore) $(LDLIBS_libblktapctl) $(PTYFUNCS_LIBS) $(LIBUUID_LIBS) $(LIBNL3_LIBS)
 
 CFLAGS_LIBXL += $(CFLAGS_libxenctrl)
 CFLAGS_LIBXL += $(CFLAGS_libxenguest)