Fix errors

Author: aryan-25

Package.swift

@@ -2,11 +2,15 @@
 
 import PackageDescription
 
+#if os(macOS)
+let platforms: [PackageDescription.SupportedPlatform]? = [.macOS(.v15)]
+#else
+let platforms: [PackageDescription.SupportedPlatform]? = nil
+#endif
+
 let package = Package(
     name: "swift-aws-lambda-runtime",
-    platforms: [
-        .macOS(.v15)
-    ],
+    platforms: platforms,
     products: [
         // this library exports `AWSLambdaRuntimeCore` and adds Foundation convenience methods
         .library(name: "AWSLambdaRuntime", targets: ["AWSLambdaRuntime"]),
@@ -21,7 +25,7 @@ let package = Package(
     dependencies: [
         .package(url: "https://github.com/apple/swift-nio.git", .upToNextMajor(from: "2.67.0")),
         .package(url: "https://github.com/apple/swift-log.git", .upToNextMajor(from: "1.5.4")),
-        .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0"),
+        .package(url: "https://github.com/apple/swift-docc-plugin.git", from: "1.0.0"),
     ],
     targets: [
         .target(

Plugins/AWSLambdaPackager/Plugin.swift

@@ -17,18 +17,6 @@ import Foundation
 import PackagePlugin
 import Synchronization
 
-#if os(macOS)
-import Darwin
-#elseif canImport(Glibc)
-import Glibc
-#elseif canImport(Musl)
-import Musl
-#elseif os(Windows)
-import ucrt
-#else
-#error("Unsupported platform")
-#endif
-
 @available(macOS 15.0, *)
 @main
 struct AWSLambdaPackager: CommandPlugin {
@@ -284,9 +272,22 @@ struct AWSLambdaPackager: CommandPlugin {
             print("\(executable.string) \(arguments.joined(separator: " "))")
         }
 
+        let fd = dup(1)
+        let stdout = fdopen(fd, "rw")!
+        defer { fclose(stdout) }
+
+        // We need to use an unsafe transfer here to get the fd into our Sendable closure.
+        // This transfer is fine, because we guarantee that the code in the outputHandler
+        // is run before we continue the functions execution, where the fd is used again.
+        // See `process.waitUntilExit()` and the following `outputSync.wait()`
+        struct UnsafeTransfer<Value>: @unchecked Sendable {
+            let value: Value
+        }
+
         let outputMutex = Mutex("")
         let outputSync = DispatchGroup()
         let outputQueue = DispatchQueue(label: "AWSLambdaPackager.output")
+        let unsafeTransfer = UnsafeTransfer(value: stdout)
         let outputHandler = { @Sendable (data: Data?) in
             dispatchPrecondition(condition: .onQueue(outputQueue))
 
@@ -311,7 +312,7 @@ struct AWSLambdaPackager: CommandPlugin {
             case .debug(let outputIndent), .output(let outputIndent):
                 print(String(repeating: " ", count: outputIndent), terminator: "")
                 print(_output)
-                fflush(stdout)
+                fflush(unsafeTransfer.value)
             }
         }