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/core/swap.c b/src/core/swap.c
index 019d32ed0d..b88a914f72 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -77,7 +77,7 @@ static int swap_set_devnode(Swap *s, const char *devnode) {
 
         assert(s);
 
-        r = hashmap_ensure_allocated(&UNIT(s)->manager->swaps_by_devnode, string_hash_func, string_compare_func);
+        r = hashmap_ensure_allocated(&UNIT(s)->manager->swaps_by_devnode, &string_hash_ops);
         if (r < 0)
                 return r;
 
@@ -1226,7 +1226,7 @@ static int swap_following_set(Unit *u, Set **_set) {
                 return 0;
         }
 
-        set = set_new(NULL, NULL);
+        set = set_new(NULL);
         if (!set)
                 return -ENOMEM;