diff options
Diffstat (limited to 'src/replication.c')
| -rw-r--r-- | src/replication.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/replication.c b/src/replication.c index e6e477896..13938a1f3 100644 --- a/src/replication.c +++ b/src/replication.c @@ -1425,12 +1425,38 @@ int cancelReplicationHandshake(void) { return 1; } +/* Mass-unblock clients because something changed in the instance that makes + * blocking no longer safe. For example clients blocked in list operations + * in an instance which turns from master to slave is unsafe, so this function + * is called when a master turns into a slave. + * + * The semantics is to send an -UNBLOCKED error to the client, disconnecting + * it at the same time. */ +void disconnectAllBlockedClients(void) { + listNode *ln; + listIter li; + + listRewind(server.clients,&li); + while((ln = listNext(&li))) { + redisClient *c = listNodeValue(ln); + + if (c->flags & REDIS_BLOCKED) { + addReplySds(c,sdsnew( + "-UNBLOCKED force unblock from blocking operation, " + "instance state changed (master -> slave?)\r\n")); + unblockClientWaitingData(c); + c->flags |= REDIS_CLOSE_AFTER_REPLY; + } + } +} + /* Set replication to the specified master address and port. */ void replicationSetMaster(char *ip, int port) { sdsfree(server.masterhost); server.masterhost = sdsdup(ip); server.masterport = port; if (server.master) freeClient(server.master); + disconnectAllBlockedClients(); /* Clients blocked in master, now slave. */ disconnectSlaves(); /* Force our slaves to resync with us as well. */ replicationDiscardCachedMaster(); /* Don't try a PSYNC. */ freeReplicationBacklog(); /* Don't allow our chained slaves to PSYNC. */ |