Add command line tools

Package.swift

@@ -19,6 +19,26 @@ var package = Package(
             name: "BluetoothLinux",
             type: libraryType,
             targets: ["BluetoothLinux"]
+        ),
+        .executable(
+            name: "hcitool",
+            targets: ["hcitool"]
+        ),
+        .executable(
+            name: "hciconfig",
+            targets: ["hciconfig"]
+        ),
+        .executable(
+            name: "gatttool",
+            targets: ["gatttool"]
+        ),
+        .executable(
+            name: "gattserver",
+            targets: ["gattserver"]
+        ),
+        .executable(
+            name: "beacon",
+            targets: ["beacon"]
         )
     ],
     dependencies: [
@@ -29,6 +49,10 @@ var package = Package(
         .package(
             url: "https://github.com/PureSwift/Socket.git",
             branch: "main"
+        ),
+        .package(
+            url: "https://github.com/apple/swift-argument-parser.git",
+            from: "1.5.0"
         )
     ],
     targets: [
@@ -55,6 +79,72 @@ var package = Package(
                 .define("ENABLE_MOCKING", .when(configuration: .debug))
             ]
         ),
+        .executableTarget(
+            name: "hcitool",
+            dependencies: [
+                "BluetoothLinux",
+                .product(
+                    name: "BluetoothGAP",
+                    package: "Bluetooth"
+                ),
+                .product(
+                    name: "ArgumentParser",
+                    package: "swift-argument-parser"
+                )
+            ]
+        ),
+        .executableTarget(
+            name: "hciconfig",
+            dependencies: [
+                "BluetoothLinux",
+                .product(
+                    name: "ArgumentParser",
+                    package: "swift-argument-parser"
+                )
+            ]
+        ),
+        .executableTarget(
+            name: "gatttool",
+            dependencies: [
+                "BluetoothLinux",
+                .product(
+                    name: "BluetoothGATT",
+                    package: "Bluetooth"
+                ),
+                .product(
+                    name: "ArgumentParser",
+                    package: "swift-argument-parser"
+                )
+            ]
+        ),
+        .executableTarget(
+            name: "gattserver",
+            dependencies: [
+                "BluetoothLinux",
+                .product(
+                    name: "BluetoothGATT",
+                    package: "Bluetooth"
+                ),
+                .product(
+                    name: "BluetoothGAP",
+                    package: "Bluetooth"
+                ),
+                .product(
+                    name: "ArgumentParser",
+                    package: "swift-argument-parser"
+                )
+            ]
+        ),
+        .executableTarget(
+            name: "beacon",
+            dependencies: [
+                "BluetoothLinux",
+                .product(
+                    name: "ArgumentParser",
+                    package: "swift-argument-parser"
+                )
+            ]
+        ),
         .target(
             name: "CBluetoothLinux"
         ),

Sources/beacon/Beacon.swift

@@ -0,0 +1,51 @@
+//
+//  Beacon.swift
+//  BluetoothLinux
+//
+//  Broadcast Bluetooth Low Energy beacons.
+//
+
+import Foundation
+import ArgumentParser
+import Bluetooth
+import BluetoothHCI
+import BluetoothLinux
+
+@main
+struct Beacon: AsyncParsableCommand {
+
+    static let configuration = CommandConfiguration(
+        commandName: "beacon",
+        abstract: "Broadcast Bluetooth Low Energy beacons.",
+        subcommands: [
+            IBeacon.self,
+            Stop.self
+        ]
+    )
+}
+
+extension HostController.ID {
+
+    /// Parse a controller identifier from a command line argument (e.g. `hci0` or `0`).
+    static func parse(_ argument: String) throws -> HostController.ID {
+        let string = argument.hasPrefix("hci") ? String(argument.dropFirst(3)) : argument
+        guard let rawValue = UInt16(string) else {
+            throw ValidationError("Invalid device identifier '\(argument)'")
+        }
+        return .init(rawValue: rawValue)
+    }
+}
+
+extension HostController {
+
+    /// Resolve the controller to use for a command.
+    static func command(device id: HostController.ID?) async throws -> HostController {
+        if let id {
+            return try await HostController(id: id)
+        }
+        guard let controller = await HostController.controllers.first else {
+            throw ValidationError("No Bluetooth controllers found.")
+        }
+        return controller
+    }
+}

Sources/beacon/IBeacon.swift

@@ -0,0 +1,50 @@
+//
+//  IBeacon.swift
+//  BluetoothLinux
+//
+
+import Foundation
+import ArgumentParser
+import Bluetooth
+import BluetoothHCI
+import BluetoothLinux
+
+struct IBeacon: AsyncParsableCommand {
+
+    static let configuration = CommandConfiguration(
+        commandName: "ibeacon",
+        abstract: "Advertise as an Apple iBeacon (requires root)."
+    )
+
+    @Option(name: [.customShort("i"), .long], help: "The controller to use (e.g. hci0).", transform: HostController.ID.parse)
+    var device: HostController.ID?
+
+    @Argument(help: "The proximity UUID of the beacon.", transform: { argument in
+        guard let uuid = UUID(uuidString: argument) else {
+            throw ValidationError("Invalid UUID '\(argument)'")
+        }
+        return uuid
+    })
+    var uuid: UUID
+
+    @Option(help: "The value identifying a group of beacons.")
+    var major: UInt16 = 0
+
+    @Option(help: "The value identifying a specific beacon within a group.")
+    var minor: UInt16 = 0
+
+    @Option(help: "The measured signal strength (in dBm) at 1 meter.")
+    var rssi: Int8 = -59
+
+    func run() async throws {
+        let controller = try await HostController.command(device: device)
+        let beacon = AppleBeacon(
+            uuid: uuid,
+            major: major,
+            minor: minor,
+            rssi: rssi
+        )
+        try await controller.iBeacon(beacon)
+        print("Advertising iBeacon \(uuid) (major: \(major), minor: \(minor)) on \(controller.name)")
+    }
+}

Sources/beacon/Stop.swift

@@ -0,0 +1,31 @@
+//
+//  Stop.swift
+//  BluetoothLinux
+//
+
+import Foundation
+import ArgumentParser
+import Bluetooth
+import BluetoothHCI
+import BluetoothLinux
+
+struct Stop: AsyncParsableCommand {
+
+    static let configuration = CommandConfiguration(
+        commandName: "stop",
+        abstract: "Stop advertising (requires root)."
+    )
+
+    @Option(name: [.customShort("i"), .long], help: "The controller to use (e.g. hci0).", transform: HostController.ID.parse)
+    var device: HostController.ID?
+
+    func run() async throws {
+        let controller = try await HostController.command(device: device)
+        do {
+            try await controller.enableLowEnergyAdvertising(false)
+        } catch HCIError.commandDisallowed {
+            // already disabled
+        }
+        print("Stopped advertising on \(controller.name)")
+    }
+}