Factor the header/RRSIG extraction out of the find paths

qpcache_find, qpcache_findrdataset, and find_headers each repeated the
same logic to pick a header and its RRSIG out of a slabheader and its
'related' link.  Pull it into store_headers(), and rename check_header()
to invalid_header() since it returns true when the header should be
skipped.

diff --git a/lib/dns/qpcache.c b/lib/dns/qpcache.c
index fd5a5eddbea0f965afe2bf5fcd82ac664b4d2a15..7e423a93d5dd2eecb47362db47c4575cd10c1bf1 100644 (file)
--- a/lib/dns/qpcache.c
+++ b/lib/dns/qpcache.c
@@ -1084,7 +1084,7 @@ check_stale_header(dns_slabheader_t *header, qpc_search_t *search) {
 }
 
 static bool
-check_header(dns_slabheader_t *header, qpc_search_t *search) {
+invalid_header(dns_slabheader_t *header, qpc_search_t *search) {
        return header == NULL || check_stale_header(header, search) ||
               !EXISTS(header) || ANCIENT(header);
 }
@@ -1156,21 +1156,43 @@ related_headers(dns_slabheader_t *header, dns_slabheader_t *sigheader,
        return false;
 }
 
+static void
+store_headers(dns_slabheader_t *tmp, dns_slabheader_t **headerp,
+             dns_slabheader_t **sigheaderp, qpc_search_t *search) {
+       dns_slabheader_t *header = NULL, *sigheader = NULL;
+       if (DNS_TYPEPAIR_TYPE(tmp->typepair) == dns_rdatatype_rrsig) {
+               header = tmp->related;
+               sigheader = tmp;
+       } else {
+               header = tmp;
+               sigheader = tmp->related;
+       }
+
+       if (invalid_header(header, search)) {
+               return;
+       }
+
+       *headerp = header;
+
+       if (invalid_header(sigheader, search)) {
+               return;
+       }
+       *sigheaderp = sigheader;
+}
+
 static void
 find_headers(qpcnode_t *node, qpc_search_t *search, dns_rdatatype_t type,
             dns_slabheader_t **foundp, dns_slabheader_t **foundsigp) {
        DNS_SLABHEADER_FOREACH(tmp, &node->headers) {
                dns_slabheader_t *header = NULL, *sigheader = NULL;
-               dns_slabheader_t *related = tmp->related;
 
                if (tmp->typepair == dns_typepair_any) {
                        INSIST(tmp->related == NULL);
                        INSIST(NEGATIVE(tmp));
-                       if (check_header(tmp, search)) {
+                       if (invalid_header(tmp, search)) {
                                /*
                                 * NEGATIVE(ANY), but it is no longer valid.
                                 */
-                               tmp = NULL;
                                continue;
                        }
                        *foundp = NULL;
@@ -1178,27 +1200,14 @@ find_headers(qpcnode_t *node, qpc_search_t *search, dns_rdatatype_t type,
                        return;
                }
 
-               if (tmp->typepair == DNS_TYPEPAIR(type)) {
-                       header = tmp;
-                       if (related != NULL) {
-                               sigheader = related;
-                       }
-               } else if (tmp->typepair == DNS_SIGTYPEPAIR(type)) {
-                       sigheader = tmp;
-                       if (related != NULL) {
-                               header = related;
-                       }
-               } else {
+               if (tmp->typepair != DNS_TYPEPAIR(type) &&
+                   tmp->typepair != DNS_SIGTYPEPAIR(type))
+               {
                        /* Not our type; continue with next slabtop */
                        continue;
                }
 
-               if (check_header(header, search)) {
-                       header = NULL;
-               }
-               if (check_header(sigheader, search)) {
-                       sigheader = NULL;
-               }
+               store_headers(tmp, &header, &sigheader, search);
 
                /*
                 * This function only sets positive headers.
@@ -1490,25 +1499,8 @@ qpcache_find(dns_db_t *db, const dns_name_t *name, dns_dbversion_t *version,
 
        DNS_SLABHEADER_FOREACH(tmp, &node->headers) {
                dns_slabheader_t *header = NULL, *sigheader = NULL;
-               if (DNS_TYPEPAIR_TYPE(tmp->typepair) == dns_rdatatype_rrsig) {
-                       sigheader = tmp;
-                       if (tmp->related != NULL) {
-                               header = tmp->related;
-                       }
-               } else {
-                       header = tmp;
-                       if (tmp->related != NULL) {
-                               sigheader = tmp->related;
-                       }
-               }
-
-               if (check_header(header, &search)) {
-                       header = NULL;
-               }
 
-               if (check_header(sigheader, &search)) {
-                       sigheader = NULL;
-               }
+               store_headers(tmp, &header, &sigheader, &search);
 
                if (header == NULL && sigheader == NULL) {
                        continue;
@@ -1762,25 +1754,7 @@ qpcache_findrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
                        continue;
                }
 
-               if (DNS_TYPEPAIR_TYPE(tmp->typepair) == dns_rdatatype_rrsig) {
-                       sigheader = tmp;
-                       if (tmp->related != NULL) {
-                               header = tmp->related;
-                       }
-               } else {
-                       header = tmp;
-                       if (tmp->related != NULL) {
-                               sigheader = tmp->related;
-                       }
-               }
-
-               if (check_header(header, &search)) {
-                       header = NULL;
-               }
-
-               if (check_header(sigheader, &search)) {
-                       sigheader = NULL;
-               }
+               store_headers(tmp, &header, &sigheader, &search);
 
                (void)related_headers(header, sigheader, typepair, &found,
                                      &foundsig);