From: Michał Kępień <michal@isc.org>
Date: Thu, 10 May 2018 07:43:38 +0000 (+0200)
Subject: Extract the do-while loop in dns__zone_updatesigs() into a separate function
X-Git-Tag: v9.13.0~26^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=31cdf770a491e94bd2a124b798eaa7117dfe2208;p=thirdparty%2Fbind9.git

Extract the do-while loop in dns__zone_updatesigs() into a separate function

The do-while loop in dns__zone_updatesigs() is hard to follow due to
heavy nesting and the 'tuple' variable also being used in the outer for
loop.  Add a comment to explain the purpose of the do-while loop.
Extract it into a separate function to decrease indentation and prevent
using 'tuple' in two different loops.
---

diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index 568e4727f7d..29537d04077 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -7288,6 +7288,25 @@ need_nsec_chain(dns_db_t *db, dns_dbversion_t *ver,
 	return (result);
 }
 
+/*%
+ * Remove all tuples with the same name and type as 'cur' from 'src' and append
+ * them to 'dst'.
+ */
+static void
+move_matching_tuples(dns_difftuple_t *cur, dns_diff_t *src, dns_diff_t *dst) {
+	do {
+		dns_difftuple_t *next = ISC_LIST_NEXT(cur, link);
+		while (next != NULL &&
+		       (cur->rdata.type != next->rdata.type ||
+			!dns_name_equal(&cur->name, &next->name)))
+			next = ISC_LIST_NEXT(next, link);
+		ISC_LIST_UNLINK(src->tuples, cur, link);
+		dns_diff_appendminimal(dst, &cur);
+		INSIST(cur == NULL);
+		cur = next;
+	} while (cur != NULL);
+}
+
 /*%
  * Add/remove DNSSEC signatures for the list of "raw" zone changes supplied in
  * 'diff'.  Gradually remove tuples from 'diff' and append them to 'zonediff'
@@ -7337,17 +7356,14 @@ dns__zone_updatesigs(dns_diff_t *diff, dns_db_t *db, dns_dbversion_t *version,
 			return (result);
 		}
 
-		do {
-			dns_difftuple_t *next = ISC_LIST_NEXT(tuple, link);
-			while (next != NULL &&
-			       (tuple->rdata.type != next->rdata.type ||
-				!dns_name_equal(&tuple->name, &next->name)))
-				next = ISC_LIST_NEXT(next, link);
-			ISC_LIST_UNLINK(diff->tuples, tuple, link);
-			dns_diff_appendminimal(zonediff->diff, &tuple);
-			INSIST(tuple == NULL);
-			tuple = next;
-		} while (tuple != NULL);
+		/*
+		 * Signature changes for all RRs with name tuple->name and type
+		 * tuple->rdata.type were appended to zonediff->diff.  Now we
+		 * remove all the "raw" changes with the same name and type
+		 * from diff (so that they are not processed by this loop
+		 * again) and append them to zonediff so that they get applied.
+		 */
+		move_matching_tuples(tuple, diff, zonediff->diff);
 	}
 	return (ISC_R_SUCCESS);
 }