Add some missing documentation

Sources/TunnelKitCore/CoreConfiguration.swift

@@ -36,9 +36,13 @@
 
 import Foundation
 
+/// Global library settings.
 public class CoreConfiguration {
+
+    /// Unique identifier of the library.
     public static let identifier = "com.algoritmico.TunnelKit"
     
+    /// Library version as seen in `Info.plist`.
     public static let version: String = {
         let bundle = Bundle(for: CoreConfiguration.self)
         guard let info = bundle.infoDictionary else {
@@ -54,15 +58,19 @@ public class CoreConfiguration {
         return info["CFBundleShortVersionString"] as? String ?? ""
     }()
 
-    // configurable
+    /// Masks private data in logs.
     public static var masksPrivateData = true
 
+    /// String representing library version.
     public static var versionIdentifier: String?
     
+    /// Enables logging of sensitive data (hardcoded to false).
     public static let logsSensitiveData = false
 }
 
 extension CustomStringConvertible {
+
+    /// Returns a masked version of `description` in case `CoreConfiguration.masksPrivateData` is `true`.
     public var maskedDescription: String {
         guard CoreConfiguration.masksPrivateData else {
             return description

Sources/TunnelKitCore/DataCount.swift

@@ -25,10 +25,13 @@
 
 import Foundation
 
-/// :nodoc:
+/// A pair of received/sent bytes count.
 public struct DataCount: Equatable {
+
+    /// Received bytes count.
     public let received: UInt
     
+    /// Sent bytes count.
     public let sent: UInt
     
     public init(_ received: UInt, _ sent: UInt) {

Sources/TunnelKitCore/DataUnit.swift

@@ -25,7 +25,7 @@
 
 import Foundation
 
-/// :nodoc:
+/// Helps expressing integers in bytes, kB, MB, GB.
 public enum DataUnit: UInt, CustomStringConvertible {
     case byte = 1
     
@@ -68,8 +68,14 @@ public enum DataUnit: UInt, CustomStringConvertible {
     }
 }
 
-/// :nodoc:
+/// Supports being represented in data unit.
-extension UInt {
+public protocol DataUnitRepresentable {
+
+    /// Returns self expressed in bytes, kB, MB, GB.
+    var descriptionAsDataUnit: String { get }
+}
+
+extension UInt: DataUnitRepresentable {
     private static let allUnits: [DataUnit] = [
         .gigabyte,
         .megabyte,
@@ -94,8 +100,7 @@ extension UInt {
     }
 }
 
-/// :nodoc:
+extension Int: DataUnitRepresentable {
-extension Int {
     public var descriptionAsDataUnit: String {
         return UInt(self).descriptionAsDataUnit
     }

Sources/TunnelKitCore/Endpoint.swift

@@ -31,7 +31,6 @@ public struct Endpoint: RawRepresentable, Codable, Equatable, CustomStringConver
     
     public let proto: EndpointProtocol
 
-    /// :nodoc:
         public init(_ address: String, _ proto: EndpointProtocol) {
         self.address = address
         self.proto = proto
@@ -74,7 +73,6 @@ public struct EndpointProtocol: RawRepresentable, Equatable, CustomStringConvert
     /// The remote port.
     public let port: UInt16
 
-    /// :nodoc:
         public init(_ socketType: SocketType, _ port: UInt16) {
         self.socketType = socketType
         self.port = port

Sources/TunnelKitCore/SecureRandom.swift

@@ -39,11 +39,16 @@ import Security.SecRandom
 import CTunnelKitCore
 import __TunnelKitUtils
 
+/// Errors returned by `SecureRandom`.
 public enum SecureRandomError: Error {
+
+    /// RNG could not be initialized.
     case randomGenerator
 }
 
+/// Generates random data in a secure fashion.
 public class SecureRandom {
+
     @available(*, deprecated)
     static func uint32FromBuffer() throws -> UInt32 {
         var randomBuffer = [UInt8](repeating: 0, count: 4)

Sources/TunnelKitManager/Keychain.swift

@@ -328,7 +328,6 @@ public class Keychain {
     
     // MARK: Helpers
     
-    /// :nodoc:
         public func setScope(query: inout [String: Any], context: String, userDefined: String?) {
         if let accessGroup = accessGroup {
             query[kSecAttrAccessGroup as String] = accessGroup

Sources/TunnelKitManager/NetworkExtensionConfiguration.swift

@@ -26,12 +26,16 @@
 import Foundation
 import NetworkExtension
 
-/// :nodoc:
+/// Extra configuration parameters to attach optionally to a `NetworkExtensionConfiguration`.
 public struct NetworkExtensionExtra {
+
+    /// A password reference to the keychain.
     public var passwordReference: Data?
 
+    /// A set of on-demand rules.
     public var onDemandRules: [NEOnDemandRule] = []
 
+    /// Disconnects on sleep if `true`.
     public var disconnectsOnSleep = false
     
     public init() {

Sources/TunnelKitManager/VPN.swift

@@ -85,6 +85,8 @@ public protocol VPN {
 }
 
 extension DispatchTimeInterval {
+
+    /// Returns self in nanoseconds.
     public var nanoseconds: UInt64 {
         switch self {
         case .seconds(let sec):

Sources/TunnelKitOpenVPNCore/Configuration.swift

@@ -51,7 +51,6 @@ extension OpenVPN {
         /// The password.
         public let password: String
         
-        /// :nodoc
         public init(_ username: String, _ password: String) {
             self.username = username
             self.password = password
@@ -355,16 +354,14 @@ extension OpenVPN {
     
     /// The immutable configuration for `OpenVPNSession`.
     public struct Configuration: Codable, Equatable {
+        struct Fallback {
+            static let cipher: Cipher = .aes128cbc
             
-        /// :nodoc:
+            static let digest: Digest = .sha1
-        public struct Fallback {
-            public static let cipher: Cipher = .aes128cbc
             
-            public static let digest: Digest = .sha1
+            static let compressionFraming: CompressionFraming = .disabled
             
-            public static let compressionFraming: CompressionFraming = .disabled
+            static let compressionAlgorithm: CompressionAlgorithm = .disabled
-            
-            public static let compressionAlgorithm: CompressionAlgorithm = .disabled
         }
         
         /// - Seealso: `ConfigurationBuilder.cipher`

Sources/TunnelKitOpenVPNCore/ConfigurationParser.swift

@@ -38,6 +38,7 @@ extension OpenVPN {
 
         // XXX: parsing is very optimistic
         
+        /// Regexes used to parse OpenVPN options.
         public struct Regex {
             
             // MARK: General

Sources/TunnelKitOpenVPNManager/OpenVPN+ProviderConfiguration.swift

@@ -74,14 +74,12 @@ extension OpenVPN {
         /// Mask private data in debug log (default is `true`).
         public var masksPrivateData = true
         
-        /// :nodoc:
                 public init(_ title: String, appGroup: String, configuration: OpenVPN.Configuration) {
             self.title = title
             self.appGroup = appGroup
             self.configuration = configuration
         }
 
-        /// :nodoc:
                 public func print() {
             if let versionIdentifier = versionIdentifier {
                 log.info("Tunnel version: \(versionIdentifier)")
@@ -97,7 +95,6 @@ extension OpenVPN {
 
 extension OpenVPN.ProviderConfiguration: NetworkExtensionConfiguration {
 
-    /// :nodoc:
         public func asTunnelProtocol(
         withBundleIdentifier tunnelBundleIdentifier: String,
         extra: NetworkExtensionExtra?
@@ -156,7 +153,6 @@ extension OpenVPN.ProviderConfiguration {
     }
 }
 
-/// :nodoc:
 extension OpenVPN.ProviderConfiguration {
     public func _appexSetDataCount(_ newValue: DataCount?) {
         defaults?.openVPNDataCount = newValue
@@ -183,7 +179,6 @@ extension OpenVPN.ProviderConfiguration {
     }
 }
 
-/// :nodoc:
 extension UserDefaults {
     public func openVPNURLForDebugLog(appGroup: String) -> URL? {
         guard let path = string(forKey: OpenVPN.ProviderConfiguration.Keys.logPath.rawValue) else {

Sources/TunnelKitWireGuardManager/WireGuard+ProviderConfiguration.swift

@@ -73,7 +73,6 @@ extension WireGuard {
 
 extension WireGuard.ProviderConfiguration: NetworkExtensionConfiguration {
 
-    /// :nodoc:
         public func asTunnelProtocol(
         withBundleIdentifier tunnelBundleIdentifier: String,
         extra: NetworkExtensionExtra?
@@ -105,7 +104,6 @@ extension WireGuard.ProviderConfiguration {
     }
 }
 
-/// :nodoc:
 extension WireGuard.ProviderConfiguration {
     public func _appexSetLastError(_ newValue: WireGuardProviderError?) {
         defaults?.wireGuardLastError = newValue
@@ -124,7 +122,6 @@ extension WireGuard.ProviderConfiguration {
     }
 }
 
-/// :nodoc:
 extension UserDefaults {
     public func wireGuardURLForDebugLog(appGroup: String) -> URL? {
         guard let path = string(forKey: WireGuard.ProviderConfiguration.Keys.logPath.rawValue) else {