improve parallel build support

* autobuild.sh: Append -j$N to MAKEFLAGS, if no -j option is there.
* libvirt.spec.in: Use %{?_smp_mflags} with "make".
Based on a patch from James Morris:
http://thread.gmane.org/gmane.comp.emulators.libvirt/8201

ChangeLog

+Thu Aug 28 11:08:15 CEST 2008 Jim Meyering <meyering@redhat.com>
+
+	improve parallel build support
+	* autobuild.sh: Append -j$N to MAKEFLAGS, if no -j option is there.
+	* libvirt.spec.in: Use %{?_smp_mflags} with "make".
+	Based on a patch from James Morris:
+	http://thread.gmane.org/gmane.comp.emulators.libvirt/8201
+
 Wed Aug 27 20:50:00 EST 2008 Daniel P. Berrange <berrange@redhat.com>
 
 	Storage pool source discovery from David Lively

autobuild.sh

@@ -21,6 +21,18 @@ rm -rf coverage
   --with-lxc \
   --with-xen-proxy
 
+# If the MAKEFLAGS envvar does not yet include a -j option,
+# add -jN where N depends on the number of processors.
+case $MAKEFLAGS in
+  *-j*) ;;
+  *) n=$(getconf _NPROCESSORS_ONLN 2> /dev/null)
+    test "$n" -gt 0 || n=1
+    n=$(expr $n + 1)
+    MAKEFLAGS="$MAKEFLAGS -j$n"
+    export MAKEFLAGS
+    ;;
+esac
+
 make
 make install
 

libvirt.spec.in

@@ -172,7 +172,7 @@ of recent versions of Linux (and other OSes).
            --with-init-script=redhat \
            --with-qemud-pid-file=%{_localstatedir}/run/libvirt_qemud.pid \
            --with-remote-file=%{_localstatedir}/run/libvirtd.pid
-make
+make %{?_smp_mflags}
 
 %install
 rm -fr %{buildroot}