build: support libnl-3

configure.ac: check for libnl-3 in addition to libnl-1

src/Makefile.am: link against libnl when needed

src/util/virnetlink.c:
support libnl3 api.  To minimize impact on code flow, wrap the
differences under the virNetlink* namespace.

Unfortunately libnl3 moves netlink/msg.h to
/usr/include/libnl3/netlink/msg.h, so the LIBNL_CFLAGS need to be added
to a bunch of places where they weren't needed with libnl1.

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric Blake <eblake@redhat.com>

configure.ac

@@ -2626,18 +2626,31 @@ AM_CONDITIONAL([WITH_VIRTUALPORT], [test "$with_virtualport" = "yes"])
 
 dnl netlink library
 
+LIBNL_ROUTE3_CFLAGS=""
+LIBNL_ROUTE3_LIBS=""
 LIBNL_CFLAGS=""
 LIBNL_LIBS=""
 have_libnl=no
 
 if test "$with_linux" = "yes"; then
-    PKG_CHECK_MODULES([LIBNL], [libnl-1 >= $LIBNL_REQUIRED], [
+    PKG_CHECK_MODULES([LIBNL], [libnl-3.0], [
         have_libnl=yes
-        AC_DEFINE_UNQUOTED([HAVE_LIBNL], 1, [whether the netlink library is available])
+        AC_DEFINE([HAVE_LIBNL3], [1], [Use libnl-3.0])
-    ], [
+        AC_DEFINE([HAVE_LIBNL], [1], [whether the netlink library is available])
-        if test "$with_macvtap" = "yes"; then
+        PKG_CHECK_MODULES([LIBNL_ROUTE3], [libnl-route-3.0])
-            AC_MSG_ERROR([libnl-devel >= $LIBNL_REQUIRED is required for macvtap support])
+        LIBNL_CFLAGS="$LIBNL_CFLAGS $LIBNL_ROUTE3_CFLAGS"
-        fi
+        LIBNL_LIBS="$LIBNL_LIBS $LIBNL_ROUTE3_LIBS"
+    ], [PKG_CHECK_MODULES([LIBNL], [libnl-1 >= $LIBNL_REQUIRED], [
+            have_libnl=yes
+            AC_DEFINE_UNQUOTED([HAVE_LIBNL], [1],
+             [whether the netlink library is available])
+            AC_DEFINE_UNQUOTED([HAVE_LIBNL1], [1],
+             [whether the netlink v1 library is available])
+        ], [
+            if test "$with_macvtap" = "yes"; then
+                AC_MSG_ERROR([libnl-devel >= $LIBNL_REQUIRED is required for macvtap support])
+            fi
+        ])
     ])
 fi
 AM_CONDITIONAL([HAVE_LIBNL], [test "$have_libnl" = "yes"])

src/Makefile.am

@@ -809,12 +809,14 @@ endif
 libvirt_driver_qemu_la_CFLAGS = $(NUMACTL_CFLAGS) \
                                 $(GNUTLS_CFLAGS) \
                                 $(LIBXML_CFLAGS) \
+                                $(LIBNL_CFLAGS) \
 		-I$(top_srcdir)/src/conf $(AM_CFLAGS)
 libvirt_driver_qemu_la_LDFLAGS = $(AM_LDFLAGS)
 libvirt_driver_qemu_la_LIBADD = $(NUMACTL_LIBS) \
 				$(CAPNG_LIBS) \
                                 $(GNUTLS_LIBS) \
-                                $(LIBXML_LIBS)
+                                $(LIBXML_LIBS) \
+				$(LIBNL_LIBS)
 if WITH_DRIVER_MODULES
 libvirt_driver_qemu_la_LIBADD += ../gnulib/lib/libgnu.la
 libvirt_driver_qemu_la_LDFLAGS += -module -avoid-version
@@ -840,8 +842,9 @@ noinst_LTLIBRARIES += libvirt_driver_lxc.la
 #libvirt_la_BUILT_LIBADD += libvirt_driver_lxc.la
 endif
 libvirt_driver_lxc_la_CFLAGS = \
+		$(LIBNL_CFLAGS) \
 		-I$(top_srcdir)/src/conf $(AM_CFLAGS)
-libvirt_driver_lxc_la_LIBADD = $(CAPNG_LIBS)
+libvirt_driver_lxc_la_LIBADD = $(CAPNG_LIBS) $(LIBNL_LIBS)
 if WITH_SECDRIVER_SELINUX
 libvirt_driver_lxc_la_LIBADD += $(SELINUX_LIBS)
 endif
@@ -941,9 +944,10 @@ noinst_LTLIBRARIES += libvirt_driver_network.la
 #libvirt_la_BUILT_LIBADD += libvirt_driver_network.la
 endif
 libvirt_driver_network_la_CFLAGS = \
+		$(LIBNL_CFLAGS) \
 		-I$(top_srcdir)/src/conf $(AM_CFLAGS)
 if WITH_DRIVER_MODULES
-libvirt_driver_network_la_LIBADD = ../gnulib/lib/libgnu.la
+libvirt_driver_network_la_LIBADD = ../gnulib/lib/libgnu.la $(LIBNL_LIBS)
 libvirt_driver_network_la_LDFLAGS = -module -avoid-version $(AM_LDFLAGS)
 endif
 libvirt_driver_network_la_SOURCES = $(NETWORK_DRIVER_SOURCES)
@@ -1086,9 +1090,9 @@ libvirt_la_BUILT_LIBADD += libvirt_driver_nwfilter.la
 noinst_LTLIBRARIES += libvirt_driver_nwfilter.la
 endif
 libvirt_driver_nwfilter_la_CFLAGS = $(LIBPCAP_CFLAGS) \
-		-I$(top_srcdir)/src/conf $(AM_CFLAGS)
+		-I$(top_srcdir)/src/conf $(LIBNL_CFLAGS) $(AM_CFLAGS)
 libvirt_driver_nwfilter_la_LDFLAGS = $(LD_AMFLAGS)
-libvirt_driver_nwfilter_la_LIBADD = $(LIBPCAP_LIBS)
+libvirt_driver_nwfilter_la_LIBADD = $(LIBPCAP_LIBS) $(LIBNL_LIBS)
 if WITH_DRIVER_MODULES
 libvirt_driver_nwfilter_la_LIBADD += ../gnulib/lib/libgnu.la
 libvirt_driver_nwfilter_la_LDFLAGS += -module -avoid-version
@@ -1540,6 +1544,7 @@ libvirt_lxc_CFLAGS =				\
 		$(YAJL_CFLAGS)			\
 		$(AUDIT_CFLAGS)			\
 		$(DBUS_CFLAGS)			\
+		$(LIBNL_CFLAGS)			\
 		-I$(top_srcdir)/src/conf	\
 		$(AM_CFLAGS)
 if HAVE_LIBBLKID

src/util/virnetlink.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2010-2011 Red Hat, Inc.
+ * Copyright (C) 2010-2012 Red Hat, Inc.
  * Copyright (C) 2010-2012 IBM Corporation
  *
  * This library is free software; you can redistribute it and/or
@@ -60,6 +60,16 @@ struct virNetlinkEventHandle {
     int deleted;
 };
 
+# ifdef HAVE_LIBNL1
+#  define virNetlinkAlloc nl_handle_alloc
+#  define virNetlinkFree nl_handle_destroy
+typedef struct nl_handle virNetlinkHandle;
+# else
+#  define virNetlinkAlloc nl_socket_alloc
+#  define virNetlinkFree nl_socket_free
+typedef struct nl_sock virNetlinkHandle;
+# endif
+
 typedef struct _virNetlinkEventSrvPrivate virNetlinkEventSrvPrivate;
 typedef virNetlinkEventSrvPrivate *virNetlinkEventSrvPrivatePtr;
 struct _virNetlinkEventSrvPrivate {
@@ -67,7 +77,7 @@ struct _virNetlinkEventSrvPrivate {
     virMutex lock;
     int eventwatch;
     int netlinkfd;
-    struct nl_handle *netlinknh;
+    virNetlinkHandle *netlinknh;
     /*Events*/
     int handled;
     size_t handlesCount;
@@ -121,7 +131,7 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
     int fd;
     int n;
     struct nlmsghdr *nlmsg = nlmsg_hdr(nl_msg);
-    struct nl_handle *nlhandle = nl_handle_alloc();
+    virNetlinkHandle *nlhandle = virNetlinkAlloc();
 
     if (!nlhandle) {
         virReportSystemError(errno,
@@ -178,7 +188,7 @@ error:
         *respbuflen = 0;
     }
 
-    nl_handle_destroy(nlhandle);
+    virNetlinkFree(nlhandle);
     return rc;
 }
 
@@ -285,7 +295,7 @@ virNetlinkEventServiceStop(void)
 
     virNetlinkEventServerLock(srv);
     nl_close(srv->netlinknh);
-    nl_handle_destroy(srv->netlinknh);
+    virNetlinkFree(srv->netlinknh);
     virEventRemoveHandle(srv->eventwatch);
 
     /* free any remaining clients on the list */
@@ -346,7 +356,7 @@ virNetlinkEventServiceStart(void)
     virNetlinkEventServerLock(srv);
 
     /* Allocate a new socket and get fd */
-    srv->netlinknh = nl_handle_alloc();
+    srv->netlinknh = virNetlinkAlloc();
 
     if (!srv->netlinknh) {
         virReportSystemError(errno,
@@ -392,7 +402,7 @@ virNetlinkEventServiceStart(void)
 error_server:
     if (ret < 0) {
         nl_close(srv->netlinknh);
-        nl_handle_destroy(srv->netlinknh);
+        virNetlinkFree(srv->netlinknh);
     }
 error_locked:
     virNetlinkEventServerUnlock(srv);