[Tarantool-patches] [PATCH v2 7/7] replication: do not ignore replica vclock on register

[Serge Petrenko via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

There was a bug in box_process_register. It decoded replica's vclock but
never used it when sending the registration stream. So the replica might
lose the data in range (replica_vclock, start_vclock).

Follow-up #5566
---
 src/box/box.cc | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/src/box/box.cc b/src/box/box.cc
index 292a54213..0bcb505a8 100644
--- a/src/box/box.cc
+++ b/src/box/box.cc
@@ -2127,8 +2127,8 @@ box_process_register(struct ev_io *io, struct xrow_header *header)
 	assert(header->type == IPROTO_REGISTER);
 
 	struct tt_uuid instance_uuid = uuid_nil;
-	struct vclock vclock;
-	xrow_decode_register_xc(header, &instance_uuid, &vclock);
+	struct vclock replica_vclock;
+	xrow_decode_register_xc(header, &instance_uuid, &replica_vclock);
 
 	if (!is_box_configured)
 		tnt_raise(ClientError, ER_LOADING);
@@ -2154,7 +2154,8 @@ box_process_register(struct ev_io *io, struct xrow_header *header)
 			  "wal_mode = 'none'");
 	}
 
-	struct gc_consumer *gc = gc_consumer_register(&replicaset.vclock,
+	vclock_reset(&replica_vclock, 0, vclock_get(&replicaset.vclock, 0));
+	struct gc_consumer *gc = gc_consumer_register(&replica_vclock,
 				"replica %s", tt_uuid_str(&instance_uuid));
 	if (gc == NULL)
 		diag_raise();
@@ -2163,9 +2164,6 @@ box_process_register(struct ev_io *io, struct xrow_header *header)
 	say_info("registering replica %s at %s",
 		 tt_uuid_str(&instance_uuid), sio_socketname(io->fd));
 
-	struct vclock start_vclock;
-	vclock_copy(&start_vclock, &replicaset.vclock);
-
 	/**
 	 * Call the server-side hook which stores the replica uuid
 	 * in _cluster space.
@@ -2180,10 +2178,10 @@ box_process_register(struct ev_io *io, struct xrow_header *header)
 
 	/*
 	 * Feed replica with WALs in range
-	 * (start_vclock, stop_vclock) so that it gets its
+	 * (replica_vclock, stop_vclock) so that it gets its
 	 * registration.
 	 */
-	relay_final_join(io->fd, header->sync, &start_vclock, &stop_vclock);
+	relay_final_join(io->fd, header->sync, &replica_vclock, &stop_vclock);
 	say_info("final data sent.");
 
 	struct xrow_header row;
-- 
2.24.3 (Apple Git-128)