iOS: show local IP in settings

apps/ios/Sources/Settings/SettingsTab.swift

@@ -20,6 +20,7 @@ struct SettingsTab: View {
     @StateObject private var connectStatus = ConnectStatusStore()
     @State private var connectingBridgeID: String?
     @State private var didAutoConnect = false
+    @State private var localIPAddress: String?
 
     var body: some View {
         NavigationStack {
@@ -29,6 +30,16 @@ struct SettingsTab: View {
                     Text(self.instanceId)
                         .font(.footnote)
                         .foregroundStyle(.secondary)
+                    LabeledContent("IP", value: self.localIPAddress ?? "—")
+                        .contextMenu {
+                            if let ip = self.localIPAddress {
+                                Button {
+                                    UIPasteboard.general.string = ip
+                                } label: {
+                                    Label("Copy", systemImage: "doc.on.doc")
+                                }
+                            }
+                        }
                 }
 
                 Section("Voice") {
@@ -83,7 +94,10 @@ struct SettingsTab: View {
                     .accessibilityLabel("Close")
                 }
             }
-            .onAppear { self.discovery.start() }
+            .onAppear {
+                self.discovery.start()
+                self.localIPAddress = Self.primaryIPv4Address()
+            }
             .onDisappear { self.discovery.stop() }
             .onChange(of: self.discovery.bridges) { _, newValue in
                 if self.didAutoConnect { return }
@@ -235,4 +249,42 @@ struct SettingsTab: View {
         }
         return bridges.first
     }
+
+    private static func primaryIPv4Address() -> String? {
+        var addrList: UnsafeMutablePointer<ifaddrs>?
+        guard getifaddrs(&addrList) == 0, let first = addrList else { return nil }
+        defer { freeifaddrs(addrList) }
+
+        var fallback: String?
+        var en0: String?
+
+        for ptr in sequence(first: first, next: { $0.pointee.ifa_next }) {
+            let flags = Int32(ptr.pointee.ifa_flags)
+            let isUp = (flags & IFF_UP) != 0
+            let isLoopback = (flags & IFF_LOOPBACK) != 0
+            let name = String(cString: ptr.pointee.ifa_name)
+            let family = ptr.pointee.ifa_addr.pointee.sa_family
+            if !isUp || isLoopback || family != UInt8(AF_INET) { continue }
+
+            var addr = ptr.pointee.ifa_addr.pointee
+            var buffer = [CChar](repeating: 0, count: Int(NI_MAXHOST))
+            let result = getnameinfo(
+                &addr,
+                socklen_t(ptr.pointee.ifa_addr.pointee.sa_len),
+                &buffer,
+                socklen_t(buffer.count),
+                nil,
+                0,
+                NI_NUMERICHOST)
+            guard result == 0 else { continue }
+            let len = buffer.prefix { $0 != 0 }
+            let bytes = len.map { UInt8(bitPattern: $0) }
+            guard let ip = String(bytes: bytes, encoding: .utf8) else { continue }
+
+            if name == "en0" { en0 = ip; break }
+            if fallback == nil { fallback = ip }
+        }
+
+        return en0 ?? fallback
+    }
 }