Add a condition to prevend freeing NULL msg when dropping a client that hasn't sent anything yet.

Author: kvap

contrib/raftable/t/000_basic.pl

@@ -71,10 +71,11 @@ sub start_nodes
 $able->psql('postgres', "select raftable('hello', '$tests{hello}');");
 $baker->psql('postgres', "select raftable('and', '$tests{and}');");
 $charlie->psql('postgres', "select raftable('goodbye', '$tests{goodbye}');");
-#$baker->stop;
+$baker->stop;
 $able->psql('postgres', "select raftable('world', '$tests{world}');");
 
-#$baker->start;
+$baker->start;
+sleep(5);
 while (my ($key, $value) = each(%tests))
 {
 	my $o = $baker->psql('postgres', "select raftable('$key');");

contrib/raftable/worker.c

@@ -169,7 +169,7 @@ static bool remove_client(Client *c)
 	int sock = c->sock;
 	Assert(sock >= 0);
 	c->sock = -1;
-	pfree(c->msg);
+	if (c->msg) pfree(c->msg);
 
 	server.clientnum--;
 	close(sock);