buildifier++

rules.bzl

@@ -61,8 +61,7 @@ def _lxcconfig_impl(ctx):
         runfiles = ctx.runfiles(files = ctx.files.src),
     )
 
-
-def lxcbundle(name, src):
+def lxcbundle(name, src, version = ""):
     rootfsname = name + "/_/rootfs"
     rootfs(name = rootfsname, src = src, out = rootfsname + ".tar")
     lxcconfig(name, src = src, out = name + "/_/meta.tar.xz")
@@ -70,15 +69,20 @@ def lxcbundle(name, src):
         name = name + "-rootfs",
         srcs = [rootfsname],
         outs = [rootfsname + ".tar.xz"],
-        cmd = "xz -f $< > $@",
-        message = "xz",
+        cmd = "xz -T0 -f $< > $@",
+        message = "XZ",
     )
+    if version:
+        outname = "{}_{}.tar".format(name, version)
+    else:
+        outname = "{}.tar".format(name)
     pkg_tar(
         name = name,
         srcs = [
             name + "-rootfs",
             name + "-meta",
         ],
+        out = outname,
     )
 
 _lxcconfig = rule(
@@ -90,7 +94,6 @@ _lxcconfig = rule(
     },
 )
 
-
 def lxcconfig(name, src, out = None):
     _lxcconfig(name = name + "/_/config", src = src)
     pkg_tar(