| 1 | //go:build !windows && !darwin && cgo |
| 2 | |
| 3 | package main |
| 4 | |
| 5 | import ( |
| 6 | "context" |
| 7 | "fmt" |
| 8 | "os" |
| 9 | "time" |
| 10 | |
| 11 | "github.com/godbus/dbus/v5" |
| 12 | ) |
| 13 | |
| 14 | const ( |
| 15 | statusNotifierWatcherName = "org.kde.StatusNotifierWatcher" |
| 16 | statusNotifierWatcherPath = dbus.ObjectPath("/StatusNotifierWatcher") |
| 17 | statusNotifierWatcherIFace = "org.kde.StatusNotifierWatcher" |
| 18 | statusNotifierPollInterval = time.Second |
| 19 | statusNotifierProbeTimeout = 750 * time.Millisecond |
| 20 | ) |
| 21 | |
| 22 | type statusNotifierBusConnection struct { |
| 23 | conn *dbus.Conn |
| 24 | cancel context.CancelFunc |
| 25 | } |
| 26 | |
| 27 | func (c *statusNotifierBusConnection) close() { |
| 28 | if c == nil { |
| 29 | return |
| 30 | } |
| 31 | if c.cancel != nil { |
| 32 | c.cancel() |
| 33 | } |
| 34 | if c.conn != nil { |
| 35 | _ = c.conn.Close() |
| 36 | } |
| 37 | } |
| 38 | |
| 39 | type statusNotifierProbe struct { |
| 40 | connection *statusNotifierBusConnection |
| 41 | connect func(context.Context) (*statusNotifierBusConnection, error) |
| 42 | } |
| 43 | |
| 44 | func newStatusNotifierProbe() *statusNotifierProbe { |
| 45 | return &statusNotifierProbe{connect: connectStatusNotifierSessionBus} |
| 46 | } |
| 47 | |
| 48 | func connectStatusNotifierSessionBus(ctx context.Context) (*statusNotifierBusConnection, error) { |
| 49 | type connectionResult struct { |
| 50 | conn *dbus.Conn |
| 51 | err error |
| 52 | } |
| 53 | |
| 54 | connCtx, cancelConn := context.WithCancel(context.Background()) |
| 55 | resultCh := make(chan connectionResult, 1) |
| 56 | go func() { |
| 57 | conn, err := dbus.SessionBusPrivateNoAutoStartup(dbus.WithContext(connCtx)) |
| 58 | if err == nil { |
| 59 | err = conn.Auth(nil) |
| 60 | } |
| 61 | if err == nil { |
| 62 | err = conn.Hello() |
| 63 | } |
| 64 | resultCh <- connectionResult{conn: conn, err: err} |
| 65 | }() |
| 66 | |
| 67 | select { |
| 68 | case result := <-resultCh: |
| 69 | if err := ctx.Err(); err != nil { |
| 70 | cancelConn() |
| 71 | if result.conn != nil { |
| 72 | _ = result.conn.Close() |
| 73 | } |
| 74 | return nil, err |
| 75 | } |
| 76 | if result.err != nil { |
| 77 | cancelConn() |
| 78 | if result.conn != nil { |
| 79 | _ = result.conn.Close() |
| 80 | } |
| 81 | return nil, result.err |
| 82 | } |
| 83 | return &statusNotifierBusConnection{conn: result.conn, cancel: cancelConn}, nil |
| 84 | case <-ctx.Done(): |
| 85 | // Canceling the connection context closes the private transport. That |
| 86 | // interrupts Auth and Hello even though godbus does not expose |
| 87 | // context-aware variants for those operations. |
| 88 | cancelConn() |
| 89 | return nil, ctx.Err() |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | func (p *statusNotifierProbe) close() { |
| 94 | if p == nil { |
| 95 | return |
| 96 | } |
| 97 | p.connection.close() |
| 98 | p.connection = nil |
| 99 | } |
| 100 | |
| 101 | func (p *statusNotifierProbe) reset() { |
| 102 | p.close() |
| 103 | } |
| 104 | |
| 105 | func (p *statusNotifierProbe) probe(ctx context.Context, itemName string) (bool, string) { |
| 106 | if p == nil { |
| 107 | return false, "no_session_bus" |
| 108 | } |
| 109 | probeCtx, cancel := context.WithTimeout(ctx, statusNotifierProbeTimeout) |
| 110 | defer cancel() |
| 111 | if p.connection == nil { |
| 112 | connect := p.connect |
| 113 | if connect == nil { |
| 114 | connect = connectStatusNotifierSessionBus |
| 115 | } |
| 116 | connection, err := connect(probeCtx) |
| 117 | if err != nil { |
| 118 | return false, "no_session_bus" |
| 119 | } |
| 120 | p.connection = connection |
| 121 | } |
| 122 | conn := p.connection.conn |
| 123 | if err := conn.BusObject().CallWithContext(probeCtx, "org.freedesktop.DBus.Peer.Ping", 0).Err; err != nil { |
| 124 | p.reset() |
| 125 | return false, "no_session_bus" |
| 126 | } |
| 127 | snapshot, err := readStatusNotifierSnapshot(probeCtx, conn, itemName) |
| 128 | if err != nil { |
| 129 | return false, "watcher_unresponsive" |
| 130 | } |
| 131 | return evaluateStatusNotifierSnapshot(snapshot, itemName) |
| 132 | } |
| 133 | |
| 134 | func readStatusNotifierSnapshot(ctx context.Context, conn *dbus.Conn, itemName string) (statusNotifierSnapshot, error) { |
| 135 | snapshot := statusNotifierSnapshot{} |
| 136 | bus := conn.Object("org.freedesktop.DBus", dbus.ObjectPath("/org/freedesktop/DBus")) |
| 137 | if err := bus.CallWithContext(ctx, "org.freedesktop.DBus.GetNameOwner", 0, statusNotifierWatcherName).Store(&snapshot.WatcherOwner); err != nil { |
| 138 | return snapshot, nil |
| 139 | } |
| 140 | if snapshot.WatcherOwner == "" { |
| 141 | return snapshot, nil |
| 142 | } |
| 143 | watcher := conn.Object(statusNotifierWatcherName, statusNotifierWatcherPath) |
| 144 | var value dbus.Variant |
| 145 | if err := watcher.CallWithContext(ctx, "org.freedesktop.DBus.Properties.Get", 0, statusNotifierWatcherIFace, "IsStatusNotifierHostRegistered").Store(&value); err != nil { |
| 146 | return snapshot, err |
| 147 | } |
| 148 | snapshot.Host, _ = value.Value().(bool) |
| 149 | if err := watcher.CallWithContext(ctx, "org.freedesktop.DBus.Properties.Get", 0, statusNotifierWatcherIFace, "RegisteredStatusNotifierItems").Store(&value); err != nil { |
| 150 | return snapshot, err |
| 151 | } |
| 152 | snapshot.Items, _ = value.Value().([]string) |
| 153 | _ = bus.CallWithContext(ctx, "org.freedesktop.DBus.GetNameOwner", 0, itemName).Store(&snapshot.ItemOwner) |
| 154 | return snapshot, nil |
| 155 | } |
| 156 | |
| 157 | func (a *App) startTrayHealthMonitor(t *desktopTray) { |
| 158 | if a == nil || t == nil { |
| 159 | return |
| 160 | } |
| 161 | ctx, cancel := context.WithCancel(a.bootContext()) |
| 162 | t.healthMu.Lock() |
| 163 | if t.healthStopped { |
| 164 | t.healthMu.Unlock() |
| 165 | cancel() |
| 166 | return |
| 167 | } |
| 168 | t.cancel = cancel |
| 169 | t.healthMu.Unlock() |
| 170 | a.goSafe("trayStatusNotifierMonitor", func() { |
| 171 | itemName := fmt.Sprintf("org.kde.StatusNotifierItem-%d-1", os.Getpid()) |
| 172 | probe := newStatusNotifierProbe() |
| 173 | defer probe.close() |
| 174 | |
| 175 | for { |
| 176 | ready, reason := probe.probe(ctx, itemName) |
| 177 | if ready { |
| 178 | a.setTrayHealth(t, "ready", "") |
| 179 | } else { |
| 180 | a.setTrayHealth(t, "unavailable", reason) |
| 181 | } |
| 182 | timer := time.NewTimer(statusNotifierPollInterval) |
| 183 | select { |
| 184 | case <-ctx.Done(): |
| 185 | timer.Stop() |
| 186 | return |
| 187 | case <-timer.C: |
| 188 | } |
| 189 | } |
| 190 | }) |
| 191 | } |
| 192 | |
| 193 | // Linux readiness is established by the DBus monitor, not systray.onReady. |
| 194 | func (a *App) trayConfigured(*desktopTray) {} |
| 195 |