Multi-platform tweaks similar to the Crypto library

Package.swift

@@ -3,6 +3,7 @@
 
 import PackageDescription
 
+#if (os(macOS) || os(iOS) || os(watchOS) || os(tvOS))
 let package = Package(
     name: "Transmission",
     platforms: [.macOS(.v10_15), .iOS(.v14)],
@@ -33,3 +34,36 @@ let package = Package(
     ],
     swiftLanguageVersions: [.v5]
 )
+#else
+let package = Package(
+    name: "Transmission",
+    platforms: [.macOS(.v10_15), .iOS(.v14)],
+    products: [
+        // Products define the executables and libraries produced by a package, and make them visible to other packages.
+        .library(
+            name: "Transmission",
+            targets: ["Transmission"]),
+    ],
+    dependencies: [
+        // Dependencies declare other packages that this package depends on.
+        // .package(url: /* package url */, from: "1.0.0"),
+        .package(url: "https://github.com/apple/swift-log.git", from: "1.0.0"),
+        .package(url: "https://github.com/OperatorFoundation/Chord", from: "0.0.13"),
+        .package(url: "https://github.com/OperatorFoundation/Datable", from: "3.1.1"),
+        .package(url: "https://github.com/OperatorFoundation/Transport", from: "2.3.8"),
+        .package(url: "https://github.com/OperatorFoundation/TransmissionLinux", from: "0.4.0"),
+    ],
+    targets: [
+        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
+        // Targets can depend on other targets in this package, and on products in packages which this package depends on.
+        .target(
+            name: "Transmission",
+            dependencies: ["Chord", "Datable", "Transport", "TransmissionLinux", .product(name: "Logging", package: "swift-log")]
+        ),
+        .testTarget(
+            name: "TransmissionTests",
+            dependencies: ["Transmission", "Datable"]),
+    ],
+    swiftLanguageVersions: [.v5]
+)
+#endif

Sources/Transmission/Connection.swift

@@ -4,6 +4,8 @@ import Datable
 import Transport
 import Logging
 
+#if (os(macOS) || os(iOS) || os(watchOS) || os(tvOS))
+
 public class Connection
 {
     var connection: Transport.Connection
@@ -401,3 +403,9 @@ public func maybeLog(message: String, logger: Logger? = nil) {
         print(message)
     }
 }
+
+#else
+
+@_exported import TransmissionLinux
+
+#endif

Sources/Transmission/Listener.swift

@@ -9,6 +9,8 @@ import Foundation
 import Network
 import Chord
 
+#if (os(macOS) || os(iOS) || os(watchOS) || os(tvOS))
+
 public class Listener
 {
     let listener: NWListener
@@ -49,3 +51,9 @@ public class Listener
         return self.queue.dequeue()
     }
 }
+
+#else
+
+@_exported import TransmissionLinux
+
+#endif