Prevent rare rbt_insert_and_remove unit test failures

When two or more absolute, two-label names are added to a completely
empty RBT, an extra, empty node for the root name will be created due to
node splitting.  check_tree() expects that, but the extra node will not
be created when just one name is added to a completely empty RBT.  This
problem could be handled inside check_tree(), but that would introduce
unnecessary complexity into it since adding a single name will result in
a different node count for a completely empty RBT (node count will be 1)
and an RBT containing only an empty node for the root name, created due
to prior node splitting (node count will be 2).  Thus, first explicitly
create a node for the root name to prevent rare check_tree() failures
caused by a single name being added in the first iteration of the
insert/remove loop.

diff --git a/lib/dns/tests/rbt_test.c b/lib/dns/tests/rbt_test.c
index 542f877c1f6a952d81ecbf1020979bf93551d320..319354edd5ec179a2368655dbb38d191527cd53b 100644 (file)
--- a/lib/dns/tests/rbt_test.c
+++ b/lib/dns/tests/rbt_test.c
@@ -910,6 +910,7 @@ insert_nodes(dns_rbt_t *mytree, char **names,
                                node->data = n;
                                names[*names_count] = isc_mem_strdup(mctx,
                                                                     namebuf);
+                               ATF_REQUIRE(names[*names_count] != NULL);
                                *names_count += 1;
                                break;
                        }
@@ -995,6 +996,7 @@ ATF_TC_BODY(rbt_insert_and_remove, tc) {
         */
        isc_result_t result;
        dns_rbt_t *mytree = NULL;
+       size_t *n;
        /*
         * We use an array for storing names instead of a set
         * structure. It's slow, but works and is good enough for tests.
@@ -1013,6 +1015,11 @@ ATF_TC_BODY(rbt_insert_and_remove, tc) {
        result = dns_rbt_create(mctx, delete_data, NULL, &mytree);
        ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);
 
+       n = isc_mem_get(mctx, sizeof(size_t));
+       ATF_REQUIRE(n != NULL);
+       result = dns_rbt_addname(mytree, dns_rootname, n);
+       ATF_REQUIRE_EQ(result, ISC_R_SUCCESS);
+
        memset(names, 0, sizeof(names));
        names_count = 0;
 
@@ -1051,6 +1058,12 @@ ATF_TC_BODY(rbt_insert_and_remove, tc) {
                }
        }
 
+       result = dns_rbt_deletename(mytree, dns_rootname, false);
+       ATF_CHECK_EQ_MSG(result, ISC_R_SUCCESS,
+                        "result: %s", isc_result_totext(result));
+       ATF_CHECK_EQ_MSG(dns_rbt_nodecount(mytree), 0,
+                        "%u != 0", dns_rbt_nodecount(mytree));
+
        dns_rbt_destroy(&mytree);
 
        dns_test_end();