hashmap: introduce hash_ops to make struct Hashmap smaller

It is redundant to store 'hash' and 'compare' function pointers in
struct Hashmap separately. The functions always comprise a pair.
Store a single pointer to struct hash_ops instead.

systemd keeps hundreds of hashmaps, so this saves a little bit of
memory.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/resolve/resolved-dns-query.c b/src/resolve/resolved-dns-query.c
index 669595d7f9..f0483c9806 100644
--- a/src/resolve/resolved-dns-query.c
+++ b/src/resolve/resolved-dns-query.c
@@ -144,7 +144,7 @@ static int dns_query_add_transaction(DnsQuery *q, DnsScope *s, DnsResourceKey *k
         assert(q);
         assert(s);
 
-        r = set_ensure_allocated(&q->transactions, NULL, NULL);
+        r = set_ensure_allocated(&q->transactions, NULL);
         if (r < 0)
                 return r;
 
@@ -166,7 +166,7 @@ static int dns_query_add_transaction(DnsQuery *q, DnsScope *s, DnsResourceKey *k
                         return r;
         }
 
-        r = set_ensure_allocated(&t->queries, NULL, NULL);
+        r = set_ensure_allocated(&t->queries, NULL);
         if (r < 0)
                 goto gc;