From: Vladimír Čunát <vladimir.cunat@nic.cz>
Date: Wed, 24 Jun 2026 08:10:37 +0000 (+0200)
Subject: lib/cache/cdb: add it_del()
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b601ecbc391880f4f9f9f7f622f75a8dd77baca3;p=thirdparty%2Fknot-resolver.git

lib/cache/cdb: add it_del()
---

diff --git a/lib/cache/cdb_api.h b/lib/cache/cdb_api.h
index 15deb79c9..b589b564a 100644
--- a/lib/cache/cdb_api.h
+++ b/lib/cache/cdb_api.h
@@ -115,13 +115,19 @@ struct kr_cdb_api {
 	int (*check_health)(kr_cdb_pt db, struct kr_cdb_stats *stat);
 
 
-	/** Start iterating; return the first *val with *key.
+	/** Start iterating: get the first *val with *key + return error code.
 	 *
 	 * - in cache: ensures a RO transaction (and commits the RW txn if any)
 	 * - in ruledb: transaction is preserved if exists, otherwise RO txn gets opened
 	 */
 	int (*it_first)(kr_cdb_pt db, struct kr_cdb_stats *stat,
 			const knot_db_val_t *key, knot_db_val_t *val);
-	/** Advance to the next *val with the same key. */
+	/** Advance to the next *val with the same key.  Return error code. */
 	int (*it_next)(kr_cdb_pt db, struct kr_cdb_stats *stat, knot_db_val_t *val);
+	/** Delete the current *val + return error code.
+	 *
+	 * You can it_next() to continue.
+	 * This assumed that you got it_first() in a RW txn.
+	 */
+	int (*it_del)(kr_cdb_pt db, struct kr_cdb_stats *stat);
 };
diff --git a/lib/cache/cdb_lmdb.c b/lib/cache/cdb_lmdb.c
index 1adbf11e0..085a29244 100644
--- a/lib/cache/cdb_lmdb.c
+++ b/lib/cache/cdb_lmdb.c
@@ -973,6 +973,21 @@ static int cdb_it_next(kr_cdb_pt db, struct kr_cdb_stats *stats, knot_db_val_t *
 	*val = val_mdb2knot(val2_m);
 	return kr_ok();
 }
+static int cdb_it_del(kr_cdb_pt db, struct kr_cdb_stats *stats)
+{
+	if (kr_fails_assert(db))
+		return kr_error(EINVAL);
+	struct lmdb_env *env = db2env(db);
+	if (kr_fails_assert(!env->is_cache && env->txn.rw_curs))
+		return kr_error(EINVAL);
+
+	MDB_cursor *curs = NULL;
+	int ret = txn_curs_get(env, &curs, stats);
+	if (ret) return ret;
+	ret = mdb_cursor_del(curs, 0/*no flags*/);
+	if (ret) return lmdb_error(env, ret);
+	return kr_ok();
+}
 
 
 const struct kr_cdb_api *kr_cdb_lmdb(void)
@@ -986,7 +1001,7 @@ const struct kr_cdb_api *kr_cdb_lmdb(void)
 		cdb_read_leq, cdb_read_less,
 		cdb_usage_percent, cdb_get_maxsize,
 		cdb_check_health,
-		cdb_it_first, cdb_it_next,
+		cdb_it_first, cdb_it_next, cdb_it_del,
 	};
 	return &api;
 }