Add iBeacon example for Pico W

README.md

@@ -39,6 +39,7 @@ Each example in this repository contains build and deployment instructions, howe
 | [pico-blink](./pico-blink) | Raspberry Pi Pico | None  | Blink an LED repeatedly. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/f2c45c18-f9a4-48b4-a941-1298ecc942cb"> |
 | [pico-blink-sdk](./pico-blink-sdk) | Raspberry Pi Pico, Pico 2 | Pico SDK | Blink an LED repeatedly with Swift & the Pico SDK. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/f2c45c18-f9a4-48b4-a941-1298ecc942cb"> |
 | [pico-w-blink-sdk](./pico-w-blink-sdk) | Raspberry Pi Pico W | Pico SDK | Blink an LED to signal 'SOS' in Morse code repeatedly with Swift & the Pico SDK. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/26223064/a4949a2e-1887-4325-8f5f-a681963c93d7"> |
+| [pico-w-ibeacon-sdk](./pico-w-ibeacon-sdk) | Raspberry Pi Pico W | Pico SDK | Advertise as an iBeacon via Bluetooth LE with Swift & the Pico SDK. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/26223064/a4949a2e-1887-4325-8f5f-a681963c93d7"> |
 | [pico2-neopixel](./pico2-neopixel) | Raspberry Pi Pico 2 | None | Control Neopixel LEDs using the RP2350 PIO. | <img width="300" src="pico2-neopixel/assets/images/example.jpg"> |
 | [nrfx-blink-sdk](./nrfx-blink-sdk) | nRF52840-DK | Zephyr SDK | Blink an LED repeatedly with Swift & Zephyr. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/ae3ff153-dd33-4460-8a08-4eac442bf7b0"> |
 | [esp32-led-strip-sdk](./esp32-led-strip-sdk) | ESP32-C6-DevKitC-1 | ESP-IDF SDK | Control NeoPixel LEDs with Swift & the ESP-IDF. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/15f8a3e0-953e-426d-ad2d-3902baf859be"> |

pico-w-ibeacon-sdk/Bluetooth.swift

@@ -0,0 +1,125 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+extension CYW43 {
+
+    final class Bluetooth {
+
+        static let shared = Bluetooth()
+
+        private var callbackRegistration = btstack_packet_callback_registration_t()
+
+        fileprivate(set) var state: State = .off
+
+        private(set) var address: BluetoothAddress = .zero
+
+        var advertisement = LowEnergyAdvertisingData() {
+            didSet {
+                let length = advertisement.length
+                advertisementBuffer = [UInt8](advertisement)
+                // data is not copied, pointer has to stay valid
+                gap_advertisements_set_data(length, &advertisementBuffer)
+            }
+        }
+
+        private var advertisementBuffer = [UInt8]()
+
+        var scanResponse = LowEnergyAdvertisingData() {
+            didSet {
+                let length = scanResponse.length
+                scanResponseBuffer = [UInt8](scanResponse)
+                // data is not copied, pointer has to stay valid
+                gap_scan_response_set_data(length, &scanResponseBuffer)
+            }
+        }
+
+        private var scanResponseBuffer = [UInt8]()
+
+        var isAdvertising = false {
+            didSet {
+                gap_advertisements_enable(isAdvertising ? 1 : 0)
+            }
+        }
+
+        private init() {
+            // register for callbacks
+            callbackRegistration.callback = _bluetooth_packet_handler
+            hci_add_event_handler(&callbackRegistration)
+        }
+
+        deinit {
+            hci_remove_event_handler(&callbackRegistration)
+        }
+    }
+}
+
+extension CYW43.Bluetooth {
+
+    func setPower(_ state: PowerState) {
+        hci_power_control(.init(rawValue: state.rawValue))
+    }
+
+    func setAdvertisementParameters(
+        advIntMin: UInt16 = 0x0030,
+        advIntMax: UInt16 = 0x0030,
+        advType: UInt8 = 0,
+        directAddressType: UInt8 = 0,
+        directAddress: inout BluetoothAddress,
+        channelMap: UInt8 = 0x07,
+        filterPolicy: UInt8 = 0x00
+    ) {
+        withUnsafeMutablePointer(to: &directAddress.bytes) {
+            gap_advertisements_set_params(advIntMin, advIntMax, advType, directAddressType, $0, channelMap, filterPolicy)
+        }
+    }
+}
+
+extension CYW43.Bluetooth {
+
+    enum PowerState: UInt8, Sendable {
+
+        case off    = 0
+        case on     = 1
+        case sleep  = 2
+    }
+
+    enum State: UInt8 {
+
+        case off            = 0
+        case initializing   = 1
+        case on             = 2
+        case halting        = 3
+        case sleeping       = 4
+        case fallingAsleep  = 5
+    }
+}
+
+// packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)
+@_documentation(visibility: internal)
+@_cdecl("bluetooth_packet_handler") 
+internal func _bluetooth_packet_handler(packetType: UInt8, channel: UInt16, packetPointer: UnsafeMutablePointer<UInt8>?, packetSize: UInt16) {
+
+    switch packetType {
+        case UInt8(HCI_EVENT_PACKET):
+            switch hci_event_packet_get_type(packetPointer) {
+                case UInt8(BTSTACK_EVENT_STATE):
+                    let rawState = btstack_event_state_get_state(packetPointer)
+                    let newValue = CYW43.Bluetooth.State(rawValue: rawState) ?? .off
+                    CYW43.Bluetooth.shared.state = newValue
+                case UInt8(HCI_EVENT_VENDOR_SPECIFIC):
+                    break
+                default:
+                    break
+            }
+        default:
+            break
+    }
+}

pico-w-ibeacon-sdk/BluetoothAddress.swift

@@ -0,0 +1,160 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+/// Bluetooth address.
+public struct BluetoothAddress: Sendable {
+
+    // MARK: - Properties
+
+    /// Underlying address bytes (host endianess).
+    public var bytes: ByteValue
+
+    // MARK: - Initialization
+
+    /// Initialize with the specifed bytes (in host endianess).
+    public init(bytes: ByteValue = (0, 0, 0, 0, 0, 0)) {
+        self.bytes = bytes
+    }
+}
+
+public extension BluetoothAddress {
+
+    /// The minimum representable value in this type.
+    static var min: BluetoothAddress { return BluetoothAddress(bytes: (.min, .min, .min, .min, .min, .min)) }
+
+    /// The maximum representable value in this type.
+    static var max: BluetoothAddress { return BluetoothAddress(bytes: (.max, .max, .max, .max, .max, .max)) }
+
+    /// A zero address.
+    static var zero: BluetoothAddress { return .min }
+}
+
+// MARK: - ByteValue
+
+extension BluetoothAddress {
+
+    /// Raw Bluetooth Address 6 byte (48 bit) value.
+    public typealias ByteValue = (UInt8, UInt8, UInt8, UInt8, UInt8, UInt8)
+
+    public static var bitWidth: Int { return 48 }
+
+    public static var length: Int { return 6 }
+}
+
+// MARK: - Equatable
+
+extension BluetoothAddress: Equatable {
+
+    public static func == (lhs: BluetoothAddress, rhs: BluetoothAddress) -> Bool {
+        return lhs.bytes.0 == rhs.bytes.0
+            && lhs.bytes.1 == rhs.bytes.1
+            && lhs.bytes.2 == rhs.bytes.2
+            && lhs.bytes.3 == rhs.bytes.3
+            && lhs.bytes.4 == rhs.bytes.4
+            && lhs.bytes.5 == rhs.bytes.5
+    }
+}
+
+// MARK: - Hashable
+
+extension BluetoothAddress: Hashable {
+
+    public func hash(into hasher: inout Hasher) {
+        withUnsafeBytes(of: bytes) { hasher.combine(bytes: $0) }
+    }
+}
+
+// MARK: - Byte Swap
+
+extension BluetoothAddress: ByteSwap {
+
+    /// A representation of this address with the byte order swapped.
+    public var byteSwapped: BluetoothAddress {
+        return BluetoothAddress(bytes: (bytes.5, bytes.4, bytes.3, bytes.2, bytes.1, bytes.0))
+    }
+}
+
+// MARK: - RawRepresentable
+
+extension BluetoothAddress: RawRepresentable {
+
+    /// Initialize a Bluetooth Address from its big endian string representation (e.g. `00:1A:7D:DA:71:13`).
+    public init?(rawValue: String) {
+        self.init(rawValue)
+    }
+
+    /// Initialize a Bluetooth Address from its big endian string representation (e.g. `00:1A:7D:DA:71:13`).
+    internal init?<S: StringProtocol>(_ rawValue: S) {
+
+        // verify string length
+        let characters = rawValue.utf8
+        guard characters.count == 17,
+            let separator = ":".utf8.first
+            else { return nil }
+
+        var bytes: ByteValue = (0, 0, 0, 0, 0, 0)
+
+        let components = characters.split(whereSeparator: { $0 == separator })
+
+        guard components.count == 6
+            else { return nil }
+
+        for (index, subsequence) in components.enumerated() {
+
+            guard subsequence.count == 2,
+                  let byte = UInt8(hexadecimal: subsequence)
+                else { return nil }
+
+            withUnsafeMutablePointer(to: &bytes) {
+                $0.withMemoryRebound(to: UInt8.self, capacity: 6) {
+                    $0.advanced(by: index).pointee = byte
+                }
+            }
+        }
+
+        self.init(bigEndian: BluetoothAddress(bytes: bytes))
+    }
+
+    /// Convert a Bluetooth Address to its big endian string representation (e.g. `00:1A:7D:DA:71:13`).
+    public var rawValue: String {
+        let bytes = self.bigEndian.bytes
+        return bytes.0.toHexadecimal()
+            + ":" + bytes.1.toHexadecimal()
+            + ":" + bytes.2.toHexadecimal()
+            + ":" + bytes.3.toHexadecimal()
+            + ":" + bytes.4.toHexadecimal()
+            + ":" + bytes.5.toHexadecimal()
+    }
+}
+
+// MARK: - CustomStringConvertible
+
+extension BluetoothAddress: CustomStringConvertible {
+
+    public var description: String { rawValue }
+}
+
+// MARK: - Data
+
+public extension BluetoothAddress {
+
+    init?<Data: DataContainer>(data: Data) {
+        guard data.count == type(of: self).length
+            else { return nil }
+        self.bytes = (data[0], data[1], data[2], data[3], data[4], data[5])
+    }
+}
+
+// MARK: - Codable
+
+#if !hasFeature(Embedded)
+extension BluetoothAddress: Codable { }
+#endif

pico-w-ibeacon-sdk/BridgingHeader.h

@@ -0,0 +1,17 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+#pragma once
+
+#include "btstack.h"
+#include "pico/stdlib.h"
+#include "pico/cyw43_arch.h"
+#include "pico/btstack_cyw43.h"

pico-w-ibeacon-sdk/ByteSwap.swift

@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+/// A Bluetooth value that is stored in the CPU native endianess format.
+public protocol ByteSwap {
+
+    /// A representation of this integer with the byte order swapped.
+    var byteSwapped: Self { get }
+}
+
+public extension ByteSwap {
+
+    /// Creates an instance from its little-endian representation, changing the
+    /// byte order if necessary.
+    ///
+    /// - Parameter value: A value to use as the little-endian representation of
+    ///   the new instance.
+    init(littleEndian value: Self) {
+        #if _endian(little)
+        self = value
+        #else
+        self = value.byteSwapped
+        #endif
+    }
+
+    /// Creates an instance from its big-endian representation, changing the byte
+    /// order if necessary.
+    ///
+    /// - Parameter value: A value to use as the big-endian representation of the
+    ///   new instance.
+    init(bigEndian value: Self) {
+        #if _endian(big)
+        self = value
+        #else
+        self = value.byteSwapped
+        #endif
+    }
+
+    /// The little-endian representation of this value.
+    ///
+    /// If necessary, the byte order of this value is reversed from the typical
+    /// byte order of this address. On a little-endian platform, for any
+    /// address `x`, `x == x.littleEndian`.
+    var littleEndian: Self {
+        #if _endian(little)
+        return self
+        #else
+        return byteSwapped
+        #endif
+    }
+
+    /// The big-endian representation of this value.
+    ///
+    /// If necessary, the byte order of this value is reversed from the typical
+    /// byte order of this address. On a big-endian platform, for any
+    /// address `x`, `x == x.bigEndian`.
+    var bigEndian: Self {
+        #if _endian(big)
+        return self
+        #else
+        return byteSwapped
+        #endif
+    }
+}