add the NFS3 protocol

Package.swift

@@ -109,7 +109,20 @@ var targets: [PackageDescription.Target] = [
             "NIOSOCKS",
             .product(name: "NIOCore", package: "swift-nio"),
             .product(name: "NIOEmbedded", package: "swift-nio"),
-        ])
+        ]),
+    .target(
+        name: "NIONFS3",
+        dependencies: [
+            .product(name: "NIOCore", package: "swift-nio"),
+        ]),
+    .testTarget(
+        name: "NIONFS3Tests",
+        dependencies: [
+            "NIONFS3",
+            .product(name: "NIOCore", package: "swift-nio"),
+            .product(name: "NIOEmbedded", package: "swift-nio"),
+            .product(name: "NIOTestUtils", package: "swift-nio"),
+        ]),
 ]
 
 let package = Package(

Package@swift-5.5.swift

@@ -109,7 +109,19 @@ var targets: [PackageDescription.Target] = [
             "NIOSOCKS",
             .product(name: "NIOCore", package: "swift-nio"),
             .product(name: "NIOEmbedded", package: "swift-nio"),
-        ])
+        ]),
+    .target(
+        name: "NIONFS3",
+        dependencies: [
+            .product(name: "NIOCore", package: "swift-nio"),
+        ]),
+    .testTarget(
+        name: "NIONFS3Tests",
+        dependencies: [
+            "NIONFS3",
+            .product(name: "NIOCore", package: "swift-nio"),
+            .product(name: "NIOTestUtils", package: "swift-nio"),
+        ]),
 ]
 
 let package = Package(

Sources/NIONFS3/MountTypes+Mount.swift

@@ -0,0 +1,85 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2021-2023 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import NIOCore
+
+// MARK: - Mount
+public struct MountCallMount: Hashable & Sendable {
+    public init(dirPath: String) {
+        self.dirPath = dirPath
+    }
+
+    public var dirPath: String
+}
+
+public struct MountReplyMount: Hashable & Sendable {
+    public init(result: NFS3Result<MountReplyMount.Okay, NFS3Nothing>) {
+        self.result = result
+    }
+
+    public struct Okay: Hashable & Sendable {
+        public init(fileHandle: NFS3FileHandle, authFlavors: [RPCAuthFlavor] = [.unix]) {
+            self.fileHandle = fileHandle
+            self.authFlavors = authFlavors
+        }
+
+        public var fileHandle: NFS3FileHandle
+        public var authFlavors: [RPCAuthFlavor] = [.unix]
+    }
+
+    public var result: NFS3Result<Okay, NFS3Nothing>
+}
+
+extension ByteBuffer {
+    public mutating func readNFS3CallMount() throws -> MountCallMount {
+        let dirPath = try self.readNFS3String()
+        return MountCallMount(dirPath: dirPath)
+    }
+
+    @discardableResult public mutating func writeNFS3CallMount(_ call: MountCallMount) -> Int {
+        self.writeNFS3String(call.dirPath)
+    }
+
+    @discardableResult public mutating func writeNFS3ReplyMount(_ reply: MountReplyMount) -> Int {
+        var bytesWritten = self.writeNFS3ResultStatus(reply.result)
+
+        switch reply.result {
+        case .okay(let reply):
+            bytesWritten += self.writeNFS3FileHandle(reply.fileHandle)
+            precondition(reply.authFlavors == [.unix] || reply.authFlavors == [.noAuth],
+                         "Sorry, anything but [.unix] / [.system] / [.noAuth] unimplemented.")
+            bytesWritten += self.writeInteger(UInt32(reply.authFlavors.count), as: UInt32.self)
+            for flavor in reply.authFlavors {
+                bytesWritten += self.writeInteger(flavor.rawValue, as: UInt32.self)
+            }
+        case .fail(_, _):
+            ()
+        }
+
+        return bytesWritten
+    }
+
+    public mutating func readNFS3ReplyMount() throws -> MountReplyMount {
+        let result = try self.readNFS3Result(readOkay: { buffer -> MountReplyMount.Okay in
+            let fileHandle = try buffer.readNFS3FileHandle()
+            let authFlavors = try buffer.readNFS3List(readEntry: { buffer in
+                try buffer.readRPCAuthFlavor()
+            })
+            return MountReplyMount.Okay(fileHandle: fileHandle, authFlavors: authFlavors)
+
+        },
+                                            readFail: { _ in NFS3Nothing() })
+        return MountReplyMount(result: result)
+    }
+}

Sources/NIONFS3/MountTypes+Null.swift

@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2021-2023 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import NIOCore
+
+// MARK: - Null
+public struct MountCallNull: Hashable & Sendable {
+    public init() {}
+}
+
+extension ByteBuffer {
+    public mutating func readMountCallNull() throws -> MountCallNull {
+        return MountCallNull()
+    }
+
+    @discardableResult public mutating func writeMountCallNull(_ call: MountCallNull) -> Int {
+        return 0
+    }
+}

Sources/NIONFS3/MountTypes+Unmount.swift

@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2021-2023 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import NIOCore
+
+// MARK: - Unmount
+public struct MountCallUnmount: Hashable & Sendable {
+    public init(dirPath: String) {
+        self.dirPath = dirPath
+    }
+
+    public var dirPath: String
+}
+
+public struct MountReplyUnmount: Hashable & Sendable {
+    public init() {}
+}
+
+extension ByteBuffer {
+    public mutating func readNFS3CallUnmount() throws -> MountCallUnmount {
+        let dirPath = try self.readNFS3String()
+        return MountCallUnmount(dirPath: dirPath)
+    }
+
+    @discardableResult public mutating func writeNFS3CallUnmount(_ call: MountCallUnmount) -> Int {
+        self.writeNFS3String(call.dirPath)
+    }
+
+    @discardableResult public mutating func writeNFS3ReplyUnmount(_ reply: MountReplyUnmount) -> Int {
+        return 0
+    }
+
+    public mutating func readNFS3ReplyUnmount() throws -> MountReplyUnmount {
+        return MountReplyUnmount()
+    }
+}

Sources/NIONFS3/NFSCallDecoder.swift

@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2021-2023 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import NIOCore
+
+public struct NFS3CallDecoder: NIOSingleStepByteToMessageDecoder {
+    public typealias InboundOut = RPCNFS3Call
+
+    public init() {}
+
+    public mutating func decode(buffer: inout ByteBuffer) throws -> RPCNFS3Call? {
+        guard let message = try buffer.readRPCMessage() else {
+            return nil
+        }
+
+        guard case (.call(let call), var body) = message else {
+            throw NFS3Error.wrongMessageType(message.0)
+        }
+
+        return try body.readNFS3Call(rpc: call)
+    }
+
+    public mutating func decodeLast(buffer: inout ByteBuffer, seenEOF: Bool) throws -> RPCNFS3Call? {
+        return try self.decode(buffer: &buffer)
+    }
+}

Sources/NIONFS3/NFSCallEncoder.swift

@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2021-2023 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import NIOCore
+
+public struct NFS3CallEncoder: MessageToByteEncoder {
+    public typealias OutboundIn = RPCNFS3Call
+
+    public init() {}
+
+    public func encode(data: RPCNFS3Call, out: inout ByteBuffer) throws {
+        out.writeRPCNFS3Call(data)
+    }
+}