io vnc sockets: Clean up SocketAddressKind switches

We have quite a few switches over SocketAddressKind.  Some have case
labels for all enumeration values, others rely on a default label.
Some abort when the value isn't a valid SocketAddressKind, others
report an error then.

Unify as follows.  Always provide case labels for all enumeration
values, to clarify intent.  Abort when the value isn't a valid
SocketAddressKind, because the program state is messed up then.

Improve a few error messages while there.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1490895797-29094-4-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/io/dns-resolver.c b/io/dns-resolver.c
index 0ac6b23c02..a407075934 100644
--- a/io/dns-resolver.c
+++ b/io/dns-resolver.c
@@ -164,9 +164,12 @@ int qio_dns_resolver_lookup_sync(QIODNSResolver *resolver,
                                                 addrs,
                                                 errp);
 
-    default:
-        error_setg(errp, "Unknown socket address kind");
+    case SOCKET_ADDRESS_KIND_FD:
+        error_setg(errp, "Unsupported socket address type 'fd'");
         return -1;
+
+    default:
+        abort();
     }
 }