2150. [bug] 'rrset-order cyclic' uniformly distribute the

                        starting point for the first response for a given
                        RRset. [RT #16655]

diff --git a/CHANGES b/CHANGES
index dfbda09e567967c2416c5384e358728a4b9f97f1..5de071a6af51d76bcf73755213f8afdca1743d61 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,7 @@
+2150.  [bug]           'rrset-order cyclic' uniformly distribute the
+                       starting point for the first response for a given
+                       RRset. [RT #16655]
+
 2147.  [bug]           libbind: remove potential buffer overflow from
                        hmac_link.c. [RT #16437]
 
@@ -1355,7 +1359,7 @@
                        [RT #6427]
 
 1555.  [func]          'rrset-order cyclic' no longer has a random starting
-                       point. [RT #7572]
+                       point per query. [RT #7572]
 
 1554.  [bug]           dig, host, nslookup failed when no nameservers
                        were specified in /etc/resolv.conf. [RT #8232]

diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index 8930d355fd0abc453c02f2efdba680e24076d3da..9d51bbaa3fb8dcd7d5819a5771646b7f7a3ecd9d 100644 (file)
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: rbtdb.c,v 1.168.2.11.2.26 2006/03/02 23:18:20 marka Exp $ */
+/* $Id: rbtdb.c,v 1.168.2.11.2.27 2007/02/26 23:20:52 marka Exp $ */
 
 /*
  * Principal Author: Bob Halley
@@ -352,6 +352,19 @@ typedef struct rbtdb_dbiterator {
 static void free_rbtdb(dns_rbtdb_t *rbtdb, isc_boolean_t log,
                       isc_event_t *event);
 
+/*%
+ * 'init_count' is used to initialize 'newheader->count' which inturn
+ * is used to determine where in the cycle rrset-order cyclic starts.
+ * We don't lock this as we don't care about simultanious updates.
+ *
+ * Note:
+ *     Both init_count and header->count can be ISC_UINT32_MAX.
+ *      The count on the returned rdataset however can't be as
+ *     that indicates that the database does not implement cyclic
+ *     processing.
+ */
+static unsigned int init_count;
+
 /*
  * Locking
  *
@@ -1513,8 +1526,8 @@ bind_rdataset(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node,
        raw = (unsigned char *)header + sizeof(*header);
        rdataset->private3 = raw;
        rdataset->count = header->count++;
-       if (header->count == ISC_UINT32_MAX)
-               header->count = 0;
+       if (rdataset->count == ISC_UINT32_MAX)
+               rdataset->count = 0;
 
        /*
         * Reset iterator state.
@@ -4341,7 +4354,7 @@ addrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
                                                rdataset->covers);
        newheader->attributes = 0;
        newheader->noqname = NULL;
-       newheader->count = 0;
+       newheader->count = init_count++;
        newheader->trust = rdataset->trust;
        if (rbtversion != NULL) {
                newheader->serial = rbtversion->serial;
@@ -4422,7 +4435,7 @@ subtractrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
        newheader->serial = rbtversion->serial;
        newheader->trust = 0;
        newheader->noqname = NULL;
-       newheader->count = 0;
+       newheader->count = init_count++;
 
        LOCK(&rbtdb->node_locks[rbtnode->locknum].lock);
 
@@ -4655,7 +4668,7 @@ loading_addrdataset(void *arg, dns_name_t *name, dns_rdataset_t *rdataset) {
        newheader->trust = rdataset->trust;
        newheader->serial = 1;
        newheader->noqname = NULL;
-       newheader->count = 0;
+       newheader->count = init_count++;
 
        result = add(rbtdb, node, rbtdb->current_version, newheader,
                     DNS_DBADD_MERGE, ISC_TRUE, NULL, 0);