network: allow empty assignment to PreferredLifetime=

Users might want to use that to unset a previous setting. The docs seem OK as
they are: we don't need to explictly mention the empty value, since it is
almost always allowed.

diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index f9bbd05dd8ba81e7f622fb4d42ac851e7e8f7bc7..9b78530334a08f0cb2adececb5d98f962badd5fe 100644 (file)
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -967,8 +967,8 @@ int config_parse_lifetime(const char *unit,
         if (r < 0)
                 return r;
 
-        /* We accept only "forever", "infinity", or "0". */
-        if (STR_IN_SET(rvalue, "forever", "infinity"))
+        /* We accept only "forever", "infinity", empty, or "0". */
+        if (STR_IN_SET(rvalue, "forever", "infinity", ""))
                 k = CACHE_INFO_INFINITY_LIFE_TIME;
         else if (streq(rvalue, "0"))
                 k = 0;