--- a/tests/test_util_jid.lua	Thu Jul 15 21:14:07 2010 +0200
+++ b/tests/test_util_jid.lua	Fri Jul 16 15:10:45 2010 +0100
@@ -54,3 +54,14 @@
 	assert_equal(bare("user@host/"), nil, "invalid JID is nil");
 end
 
+function compare(compare)
+	assert_equal(compare("host", "host"), true, "host should match");
+	assert_equal(compare("host", "other-host"), false, "host should not match");
+	assert_equal(compare("other-user@host/resource", "host"), true, "host should match");
+	assert_equal(compare("other-user@host", "user@host"), false, "user should not match");
+	assert_equal(compare("user@host", "host"), true, "host should match");
+	assert_equal(compare("user@host/resource", "host"), true, "host should match");
+	assert_equal(compare("user@host/resource", "user@host"), true, "user and host should match");
+	assert_equal(compare("user@other-host", "host"), false, "host should not match");
+	assert_equal(compare("user@other-host", "user@host"), false, "host should not match");
+end

--- a/util/jid.lua	Thu Jul 15 21:14:07 2010 +0200
+++ b/util/jid.lua	Fri Jul 16 15:10:45 2010 +0100
@@ -78,4 +78,17 @@
 	return nil; -- Invalid JID
 end
 
+function compare(jid, acl)
+	-- compare jid to single acl rule
+	-- TODO compare to table of rules?
+	local jid_node, jid_host, jid_resource = _split(jid);
+	local acl_node, acl_host, acl_resource = _split(acl);
+	if ((acl_node ~= nil and acl_node == jid_node) or acl_node == nil) and
+		((acl_host ~= nil and acl_host == jid_host) or acl_host == nil) and
+		((acl_resource ~= nil and acl_resource == jid_resource) or acl_resource == nil) then
+		return true
+	end
+	return false
+end
+
 return _M;