navigation.go RawHistoryFolder

1package protocol
2
3// NavigationCapabilities advertises optional client-driven navigation
4// features. Presenting a picker is not one of them: every attached client
5// renders the picker itself, so the serving daemon only negotiates the
6// features it must act on.
7type NavigationCapabilities uint8
8
9const (
10	NavigationCapabilityInventory NavigationCapabilities = 1 << iota
11)
12
13func validNavigationCapabilities(capabilities NavigationCapabilities) bool {
14	return capabilities&^NavigationCapabilityInventory == 0
15}
16
17// ValidateNavigation rejects capabilities this protocol does not define and
18// accepts the inventory capability only on the intents whose attachment can
19// serve it. Both the client before dialing and the serving daemon on Hello use
20// this rule, so a request the client admits is one the daemon accepts.
21func ValidateNavigation(intent uint8, capabilities NavigationCapabilities) error {
22	if !validNavigationCapabilities(capabilities) {
23		return ErrInvalidNavigation
24	}
25	switch intent {
26	case IntentNew, IntentAttach, IntentResume:
27		return nil
28	default:
29		if capabilities != 0 {
30			return ErrInvalidNavigation
31		}
32		return nil
33	}
34}