src: rework of the hash-cache infrastructure

Currently, the caching system is implemented in a two layer
architecture: hashtable (inner layer) and cache (upper layer).
This patch reworks the hash-cache infrastructure to solve some
initial design problems to make it more flexible, the main strong
points of this patch are:

* Memory handling is done in the cache layer, not in the inner
hashtable layer. This removes one of the main dependencies between
the hashtable and the cache classes.
* Remove excessive encapsulation: the former cache used to hide a
lot of details of the inner hashtable implementation.
* Fix over-hashing of some operations: lookup-delete-add required
three hash calculations. Similarly, the update-or-add operation
required two hash calculations. Now, we calculate the hash once
and re-use the value how many times as we need.

This patch simplifies the caching system. As a result, we save ~130
lines of code. Small code means and less complexity means less
chance to have bugs.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 0 insertions, 1 deletions

diff --git a/include/network.h b/include/network.h
index 40bb2b2..619ce3e 100644
--- a/include/network.h
+++ b/include/network.h
@@ -75,7 +75,6 @@ enum {
 	__hdr;							\
 })
 
-struct us_conntrack;
 struct mcast_sock;
 
 enum {