yep steam classes are faster...

Sources/apk/Utility/FileInputStream.swift

@@ -7,14 +7,14 @@ import Foundation
 import Darwin
 import System
 
-public struct FileInputStream: InputStream {
+public class FileInputStream: InputStream {
   private var _hnd: FileHandle
 
   public init(_ fileURL: URL) throws {
     self._hnd = try FileHandle(forReadingFrom: fileURL)
   }
 
-  public mutating func seek(_ whence: StreamWhence) throws(StreamError) {
+  public override func seek(_ whence: Whence) throws(StreamError) {
     let applyOffset = { (position: UInt64, offset: Int) throws(StreamError) -> UInt64 in
       if offset < 0 {
         let (newPosition, overflow) = position.subtractingReportingOverflow(UInt64(-offset))
@@ -55,7 +55,7 @@ public struct FileInputStream: InputStream {
     }
   }
 
-  public var tell: Int {
+  public override var tell: Int {
     get throws(StreamError) {
       let offset: UInt64
       do { offset = try self._hnd.offset() }
@@ -67,7 +67,7 @@ public struct FileInputStream: InputStream {
     }
   }
 
-  public mutating func read(_ count: Int) throws(StreamError) -> Data {
+  public override func read(_ count: Int) throws(StreamError) -> Data {
     do {
       return try self._hnd.read(upToCount: count) ?? Data()
     } catch {
@@ -75,7 +75,7 @@ public struct FileInputStream: InputStream {
     }
   }
 
-  public mutating func read(_ buffer: UnsafeMutablePointer<UInt8>, maxLength len: Int) throws(StreamError) -> Int {
+  public override func read(_ buffer: UnsafeMutablePointer<UInt8>, maxLength len: Int) throws(StreamError) -> Int {
     let res = unistd.read(self._hnd.fileDescriptor, buffer, len)
     if res < 0 {
       throw .fileHandleError(Errno(rawValue: errno))

Sources/apk/Utility/GZip.swift

@@ -18,7 +18,7 @@ struct GZipReader: ~Copyable {
     inflateEnd(&zstream)
   }
 
-  mutating func read(inStream stream: inout any InputStream) throws(GZipError) -> Data {
+  mutating func read(inStream stream: InputStream) throws(GZipError) -> Data {
     // Initialise zlib if this is the first time we're called
     // otherwise reset the stream in anticipation of reading the next concatenated stream
     var zerr = if self.zstream.state == nil {

Sources/apk/Utility/InputStream.swift

@@ -5,19 +5,24 @@
 
 import Foundation
 
-public protocol InputStream: Stream, IteratorProtocol where Element == UInt8 {
-  mutating func read(_ count: Int) throws(StreamError) -> Data
-  mutating func read(_ buffer: UnsafeMutablePointer<UInt8>, maxLength len: Int) throws(StreamError) -> Int
-}
+public class InputStream: Stream, IteratorProtocol {
+  public typealias Element = UInt8
 
-public extension InputStream {
-  mutating func read(_ size: Int, items: Int) throws(StreamError) -> Data {
-    try self.read(size * items)
+  public func read(_ count: Int) throws(StreamError) -> Data {
+    throw .notImplemented
   }
-}
 
-public extension InputStream {
-  mutating func next() -> UInt8? {
+  public func read(_ buffer: UnsafeMutablePointer<UInt8>, maxLength len: Int) throws(StreamError) -> Int {
+    throw .notImplemented
+  }
+
+  public func next() -> UInt8? {
     try? self.read(1).first
   }
 }
+
+public extension InputStream {
+  func read(_ size: Int, items: Int) throws(StreamError) -> Data {
+    try self.read(size * items)
+  }
+}

Sources/apk/Utility/MemoryInputStream.swift

@@ -6,7 +6,7 @@
 import Foundation
 import System
 
-public struct MemoryInputStream: InputStream {
+public class MemoryInputStream: InputStream {
   private var _buf: ContiguousArray<UInt8>! = nil
   private let _sli: ArraySlice<UInt8>
   private let _ptr: UnsafeBufferPointer<UInt8>
@@ -50,7 +50,7 @@ public struct MemoryInputStream: InputStream {
   }
   */
 
-  public mutating func seek(_ whence: StreamWhence) throws(StreamError) {
+  public override func seek(_ whence: Whence) throws(StreamError) {
     let (position, overflow) = switch whence {
     case .set(let position):   (position, false)
     case .current(let offset): self._idx.addingReportingOverflow(offset)
@@ -65,13 +65,13 @@ public struct MemoryInputStream: InputStream {
     }
   }
 
-  public var tell: Int {
+  public override var tell: Int {
     get throws(StreamError) {
       self._idx
     }
   }
 
-  public mutating func read(_ count: Int) throws(StreamError) -> Data {
+  public override func read(_ count: Int) throws(StreamError) -> Data {
     let beg = min(self._idx, self._len)
     let end = min(self._idx + count, self._len)
     let bytes = Data(self._ptr[beg..<end])
@@ -79,7 +79,7 @@ public struct MemoryInputStream: InputStream {
     return bytes
   }
 
-  public mutating func read(_ buffer: UnsafeMutablePointer<UInt8>, maxLength count: Int) throws(StreamError) -> Int {
+  public override func read(_ buffer: UnsafeMutablePointer<UInt8>, maxLength count: Int) throws(StreamError) -> Int {
     let beg = min(self._idx, self._len)
     let end = min(self._idx + count, self._len)
     let len = beg.distance(to: end)
@@ -88,7 +88,7 @@ public struct MemoryInputStream: InputStream {
     return self._ptr.copyBytes(to: buf, from: beg..<end)
   }
 
-  public mutating func next() -> UInt8? {
+  public override func next() -> UInt8? {
     if _fastPath(self._idx < self._len) {
       defer { self._idx += 1 }
       return self._ptr[self._idx]

Sources/apk/Utility/Stream.swift

@@ -6,19 +6,29 @@
 import Foundation
 import System
 
-public protocol Stream {
-  mutating func seek(_ whence: StreamWhence) throws(StreamError)
-  var tell: Int { get throws(StreamError) }
+public class Stream {
+  func seek(_ whence: Whence) throws(StreamError) {
+    throw .unsupported
+  }
+
+  var tell: Int {
+    get throws(StreamError) {
+      throw .unsupported
+    }
+  }
 }
 
-public enum StreamWhence {
-  case set(_ position: Int)
-  case current(_ offset: Int)
-  case end(_ offset: Int)
+extension Stream {
+  public enum Whence {
+    case set(_ position: Int)
+    case current(_ offset: Int)
+    case end(_ offset: Int)
+  }
 }
 
 public enum StreamError: Error, LocalizedError {
   case unsupported
+  case notImplemented
   case seekRange
   case overflow
   case fileHandleError(_ error: any Error)
@@ -27,6 +37,7 @@ public enum StreamError: Error, LocalizedError {
   public var errorDescription: String? {
     switch self {
     case .unsupported: "Unsupported operation"
+    case .notImplemented: "The stream object doesn't implement this function"
     case .seekRange: "Seek out of range"
     case .overflow: "Stream position overflowed"
     case .fileHandleError(let error): "Error from file handle: \(error.localizedDescription)"

Sources/apk/Utility/TarMemoryReader.swift

@@ -18,7 +18,7 @@ public struct TarReader {
     case directory(name: String)
   }
 
-  public static func read<S: InputStream>(_ stream: inout S) throws -> [Entry] {
+  public static func read(_ stream: InputStream) throws -> [Entry] {
     var entries = [Entry]()
 
     while true {