Add Linux support

packages/moxdns_linux/lib/moxdns_linux.dart

@@ -0,0 +1,41 @@
+import "package:moxdns/moxdns.dart";
+import "package:moxdns_platform_interface/moxdns_platform_interface.dart";
+import "package:flutter/services.dart";
+
+class MoxdnsLinuxPlugin extends MoxdnsPlatform {
+  final MethodChannel _channel;
+
+  MoxdnsLinuxPlugin() : _channel = MethodChannel("me.polynom.moxdns_linux"), super();
+
+  static void registerWith() {
+    print("MoxdnsLinuxPlugin: Registering implementation");
+    MoxdnsPlugin.platform = MoxdnsLinuxPlugin();
+  }
+  
+  @override
+  Future<List<SrvRecord>> srvQuery(String domain, bool dnssec) async {
+    try {
+      final List<dynamic> results = await _channel.invokeMethod("srvQuery", {
+          "domain": domain,
+          "dnssec": dnssec
+      });
+      final records = List<SrvRecord>.empty(growable: true);
+      for (var record in results) {
+        if (record == null) {
+          continue;
+        }
+        final rr = Map<String, dynamic>.from(record);
+        records.add(SrvRecord(
+            rr["target"]!,
+            rr["port"]! as int,
+            rr["priority"]! as int,
+            rr["weight"]! as int
+        ));
+      }
+      return records;
+    } on PlatformException catch(e) {
+      print("moxdns_linux: $e");
+      return const [];
+    }
+  }
+}

packages/moxdns_linux/lib/moxdns_linux_method_channel.dart

@@ -0,0 +1,17 @@
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart';
+
+import 'moxdns_linux_platform_interface.dart';
+
+/// An implementation of [MoxdnsLinuxPlatform] that uses method channels.
+class MethodChannelMoxdnsLinux extends MoxdnsLinuxPlatform {
+  /// The method channel used to interact with the native platform.
+  @visibleForTesting
+  final methodChannel = const MethodChannel('moxdns_linux');
+
+  @override
+  Future<String?> getPlatformVersion() async {
+    final version = await methodChannel.invokeMethod<String>('getPlatformVersion');
+    return version;
+  }
+}

packages/moxdns_linux/lib/moxdns_linux_platform_interface.dart

@@ -0,0 +1,29 @@
+import 'package:plugin_platform_interface/plugin_platform_interface.dart';
+
+import 'moxdns_linux_method_channel.dart';
+
+abstract class MoxdnsLinuxPlatform extends PlatformInterface {
+  /// Constructs a MoxdnsLinuxPlatform.
+  MoxdnsLinuxPlatform() : super(token: _token);
+
+  static final Object _token = Object();
+
+  static MoxdnsLinuxPlatform _instance = MethodChannelMoxdnsLinux();
+
+  /// The default instance of [MoxdnsLinuxPlatform] to use.
+  ///
+  /// Defaults to [MethodChannelMoxdnsLinux].
+  static MoxdnsLinuxPlatform get instance => _instance;
+  
+  /// Platform-specific implementations should set this with their own
+  /// platform-specific class that extends [MoxdnsLinuxPlatform] when
+  /// they register themselves.
+  static set instance(MoxdnsLinuxPlatform instance) {
+    PlatformInterface.verifyToken(instance, _token);
+    _instance = instance;
+  }
+
+  Future<String?> getPlatformVersion() {
+    throw UnimplementedError('platformVersion() has not been implemented.');
+  }
+}