Selectively uncompress kernel binary from archive (#7)

Sources/APIServer/Kernel/KernelService.swift

@@ -77,9 +77,8 @@ actor KernelService {
             .setDescription("Unpacking kernel")
         ])
         let archiveReader = try ArchiveReader(file: tarFile)
-        try archiveReader.extractContents(to: tempDir)
-        let kernelPath = tempDir.appendingPathComponent(kernelFilePath).resolvingSymlinksInPath()
-        try self.installKernel(kernelFile: kernelPath, platform: platform)
+        let kernelFile = try archiveReader.extractFile(from: kernelFilePath, to: tempDir)
+        try self.installKernel(kernelFile: kernelFile, platform: platform)
 
         if !FileManager.default.fileExists(atPath: tar.absoluteString) {
             try FileManager.default.removeItem(at: tarFile)
@@ -108,3 +107,14 @@ actor KernelService {
         return Kernel(path: defaultKernelPath, platform: platform)
     }
 }
+
+extension ArchiveReader {
+    fileprivate func extractFile(from: String, to directory: URL) throws -> URL {
+        let (_, data) = try self.extractFile(path: from)
+        try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true, attributes: nil)
+        let fileName = URL(filePath: from).lastPathComponent
+        let fileURL = directory.appendingPathComponent(fileName)
+        try data.write(to: fileURL, options: .atomic)
+        return fileURL
+    }
+}

Sources/CLI/System/SystemStart.swift

@@ -85,13 +85,13 @@ extension Application {
                 )
             }
 
-            var kernelConfigured: Bool = false
+            var kernelConfigured: Bool = true
             var missingDependencies: [Dependencies] = []
             if await !initImageExists() {
                 missingDependencies.append(.initFs)
             }
             if await !kernelExists() {
-                kernelConfigured = true
+                kernelConfigured = false
                 missingDependencies.append(.kernel)
             }
             guard missingDependencies.count > 0 else {

Sources/ContainerClient/XPC+.swift

@@ -94,7 +94,6 @@ public enum XPCKeys: String {
     case kernelTarURL
     case kernelFilePath
     case setDefault
-    case installedKernels
     case systemPlatform
     case kernelName
 }