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>

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();
     }
 }
 

ui/vnc.c

@@ -129,10 +129,13 @@ static void vnc_init_basic_info(SocketAddress *addr,
         info->family = NETWORK_ADDRESS_FAMILY_UNIX;
         break;
 
-    default:
-        error_setg(errp, "Unsupported socket kind %d",
-                   addr->type);
+    case SOCKET_ADDRESS_KIND_VSOCK:
+    case SOCKET_ADDRESS_KIND_FD:
+        error_setg(errp, "Unsupported socket address type %s",
+                   SocketAddressKind_lookup[addr->type]);
         break;
+    default:
+        abort();
     }
 
     return;
@@ -411,10 +414,13 @@ VncInfo *qmp_query_vnc(Error **errp)
             info->family = NETWORK_ADDRESS_FAMILY_UNIX;
             break;
 
-        default:
-            error_setg(errp, "Unsupported socket kind %d",
-                       addr->type);
+        case SOCKET_ADDRESS_KIND_VSOCK:
+        case SOCKET_ADDRESS_KIND_FD:
+            error_setg(errp, "Unsupported socket address type %s",
+                       SocketAddressKind_lookup[addr->type]);
             goto out_error;
+        default:
+            abort();
         }
 
         info->has_host = true;

util/qemu-sockets.c

@@ -1337,9 +1337,7 @@ char *socket_address_to_string(struct SocketAddress *addr, Error **errp)
         break;
 
     default:
-        error_setg(errp, "socket family %d unsupported",
-                   addr->type);
-        return NULL;
+        abort();
     }
     return buf;
 }