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, 5 insertions, 5 deletions

diff --git a/src/cache_lifetime.c b/src/cache_lifetime.c
index ad3416a..639d8c1 100644
--- a/src/cache_lifetime.c
+++ b/src/cache_lifetime.c
@@ -17,12 +17,12 @@
  */
 
 #include <stdio.h>
-#include "us-conntrack.h"
 #include "cache.h"
 #include <sys/time.h>
 #include <time.h>
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
 
-static void lifetime_add(struct us_conntrack *u, void *data)
+static void lifetime_add(struct cache_object *obj, void *data)
 {
 	long *lifetime = data;
 	struct timeval tv;
@@ -32,15 +32,15 @@ static void lifetime_add(struct us_conntrack *u, void *data)
 	*lifetime = tv.tv_sec;
 }
 
-static void lifetime_update(struct us_conntrack *u, void *data)
+static void lifetime_update(struct cache_object *obj, void *data)
 {
 }
 
-static void lifetime_destroy(struct us_conntrack *u, void *data)
+static void lifetime_destroy(struct cache_object *obj, void *data)
 {
 }
 
-static int lifetime_dump(struct us_conntrack *u, 
+static int lifetime_dump(struct cache_object *obj, 
 			 void *data, 
 			 char *buf, 
 			 int type)