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/device.c b/src/core/device.c
index 0f28a16874..11c4261081 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -304,7 +304,7 @@ static int device_update_unit(Manager *m, struct udev_device *dev, const char *p
                         goto fail;
                 }
 
-                r = hashmap_ensure_allocated(&m->devices_by_sysfs, string_hash_func, string_compare_func);
+                r = hashmap_ensure_allocated(&m->devices_by_sysfs, &string_hash_ops);
                 if (r < 0)
                         goto fail;
 
@@ -517,7 +517,7 @@ static int device_following_set(Unit *u, Set **_set) {
                 return 0;
         }
 
-        set = set_new(NULL, NULL);
+        set = set_new(NULL);
         if (!set)
                 return -ENOMEM;