Added NetlinkSocketAddress

Author: colemancda

Sources/Netlink/SocketAddress.swift

@@ -0,0 +1,48 @@
+//
+//  SocketAddress.swift
+//  
+//
+//  Created by Alsey Coleman Miller on 4/22/22.
+//
+
+import Foundation
+import SystemPackage
+
+@frozen
+public struct NetlinkSocketAddress: Equatable, Hashable, SocketAddress {
+        
+    public typealias ProtocolID = NetlinkSocketProtocol
+    
+    public var processID: ProcessID
+    
+    public var group: CInt
+    
+    public init(
+        processID: ProcessID = .current,
+        group: CInt = 0
+    ) {
+        self.processID = processID
+        self.group = group
+    }
+    
+    public func withUnsafePointer<Result>(
+      _ body: (UnsafePointer<CInterop.SocketAddress>, UInt32) throws -> Result
+    ) rethrows -> Result {
+        let address = CInterop.NetlinkSocketAddress(
+            processID: processID,
+            group: group
+        )
+        return try address.withUnsafePointer(body)
+    }
+    
+    public static func withUnsafePointer(
+        _ body: (UnsafeMutablePointer<CInterop.SocketAddress>, UInt32) throws -> ()
+    ) rethrows -> Self {
+        var value = CInterop.NetlinkSocketAddress()
+        try value.withUnsafeMutablePointer(body)
+        return Self.init(
+            processID: .init(rawValue: numericCast(value.nl_pid)),
+            group: .init(bitPattern: value.nl_groups)
+        )
+    }
+}