[iptables PATCH v4 1/5] nft: Simplify nft_is_chain_compatible()

[Phil Sutter]

Make use of nft_{table,chain}_builtin_find() instead of open-coding the
list traversal. Since code is pretty obvious now, drop the comments
added earlier.

Fixes: e774b15299c27 ("nft: Review is_*_compatible() routines")
Signed-off-by: Phil Sutter <p...@nwl.cc>
---
 iptables/nft.c | 34 +++++++++-------------------------
 1 file changed, 9 insertions(+), 25 deletions(-)

diff --git a/iptables/nft.c b/iptables/nft.c
index 1fd3837f2d334..25e538b7e35d7 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -3077,11 +3077,12 @@ static int nft_is_rule_compatible(struct nftnl_rule 
*rule, void *data)
 
 static int nft_is_chain_compatible(struct nftnl_chain *c, void *data)
 {
-       const struct builtin_chain *chains = NULL, *chain = NULL;
-       const char *table, *name, *type;
+       const struct builtin_table *table;
+       const struct builtin_chain *chain;
+       const char *tname, *cname, *type;
        struct nft_handle *h = data;
        enum nf_inet_hooks hook;
-       int i, prio;
+       int prio;
 
        if (nftnl_rule_foreach(c, nft_is_rule_compatible, NULL))
                return -1;
@@ -3089,33 +3090,16 @@ static int nft_is_chain_compatible(struct nftnl_chain 
*c, void *data)
        if (!nft_chain_builtin(c))
                return 0;
 
-       /* find chain's table in builtin tables */
-       table = nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
-       for (i = 0; i < NFT_TABLE_MAX; i++) {
-               const char *cur_table = h->tables[i].name;
-
-               if (!cur_table || strcmp(cur_table, table))
-                       continue;
-
-               chains = h->tables[i].chains;
-               break;
-       }
-       if (!chains)
+       tname = nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
+       table = nft_table_builtin_find(h, tname);
+       if (!table)
                return -1;
 
-       /* find chain in builtin chain list */
-       name = nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
-       for (i = 0; i < NF_INET_NUMHOOKS && chains[i].name; i++) {
-               if (strcmp(name, chains[i].name))
-                       continue;
-
-               chain = &chains[i];
-               break;
-       }
+       cname = nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
+       chain = nft_chain_builtin_find(table, cname);
        if (!chain)
                return -1;
 
-       /* compare properties */
        type = nftnl_chain_get_str(c, NFTNL_CHAIN_TYPE);
        prio = nftnl_chain_get_u32(c, NFTNL_CHAIN_PRIO);
        hook = nftnl_chain_get_u32(c, NFTNL_CHAIN_HOOKNUM);
-- 
2.19.0