[iptables PATCH v4 2/5] nft: Simplify flush_chain_cache()

[Phil Sutter]

With all the checks for 'tablename' being non-NULL, this code was rather
stupid and really hard to read. And the fix is indeed quite simple: If a
table name was given, use nft_table_builtin_find() and just flush its
chain cache. Otherwise iterate over all builtin tables without any
conditionals for 'tablename'.

Fixes: d4b0d248cc057 ("nft: Reduce indenting level in flush_chain_cache()")
Signed-off-by: Phil Sutter <p...@nwl.cc>
---
 iptables/nft.c | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/iptables/nft.c b/iptables/nft.c
index 25e538b7e35d7..dafb879ebd6f0 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -793,27 +793,25 @@ static int __flush_chain_cache(struct nftnl_chain *c, 
void *data)
 
 static void flush_chain_cache(struct nft_handle *h, const char *tablename)
 {
+       const struct builtin_table *table;
        int i;
 
+       if (tablename) {
+               table = nft_table_builtin_find(h, tablename);
+               if (!table || !h->table[table->type].chain_cache)
+                       return;
+               nftnl_chain_list_foreach(h->table[table->type].chain_cache,
+                                        __flush_chain_cache, NULL);
+               return;
+       }
+
        for (i = 0; i < NFT_TABLE_MAX; i++) {
                if (h->tables[i].name == NULL)
                        continue;
 
-               if (tablename && strcmp(h->tables[i].name, tablename))
+               if (!h->table[i].chain_cache)
                        continue;
 
-               if (!h->table[i].chain_cache) {
-                       if (tablename)
-                               return;
-                       continue;
-               }
-
-               if (tablename) {
-                       nftnl_chain_list_foreach(h->table[i].chain_cache,
-                                                __flush_chain_cache, NULL);
-                       return;
-               }
-
                nftnl_chain_list_free(h->table[i].chain_cache);
                h->table[i].chain_cache = NULL;
        }
-- 
2.19.0