Separate LC3VMCore as a library to share common code.

Package.swift

@@ -4,22 +4,31 @@
 import PackageDescription
 
 let package = Package(
-    name: "lc3vm",
+    name: "LC3VM",
+    products: [
+        // Products define the executables and libraries produced by a package, and make them visible to other packages.
+        .executable(name: "LC3VM", targets: ["LC3VM"]),
+        .library(name: "LC3VMCore", targets: ["LC3VMCore"]),
+    ],
     dependencies: [
         .package(url: "https://github.com/apple/swift-argument-parser", from: "1.0.0"),
     ],
     targets: [
         // Targets are the basic building blocks of a package, defining a module or a test suite.
         // Targets can depend on other targets in this package and products from dependencies.
         .executableTarget(
-            name: "lc3vm",
+            name: "LC3VM",
             dependencies: [
+                .target(name: "LC3VMCore"),
                 .product(name: "ArgumentParser", package: "swift-argument-parser"),
             ]
         ),
+        .target(
+            name: "LC3VMCore"
+        ),
         .testTarget(
             name: "lc3vmTests",
-            dependencies: ["lc3vm"]
+            dependencies: ["LC3VMCore"]
         ),
     ]
 )

Sources/LC3VM.swift → Sources/LC3VM/LC3VM.swift

@@ -1,12 +1,13 @@
 //
-//  lc3vm.swift
+//  LC3VM.swift
 //  lc3vm
 //
 //  Created by İbrahim Çetin on 9.10.2024.
 //
 
 import ArgumentParser
 import Foundation
+import LC3VMCore
 
 /// The LC-3 virtual machine.
 @main
@@ -17,26 +18,24 @@ struct LC3VM: AsyncParsableCommand {
     var binary: URL
 
     func run() async throws {
+        // Create the LC-3 hardware
         let hardware = Hardware()
 
         // Read the binary file and load it into memory
         try hardware.readImage(binary)
 
+        // Set up the signal handler
         signal(SIGINT) { handle_interrupt($0) }
+        // Disable input buffering
         disable_input_buffering()
 
-        // Set condition register to zero which value is 010 (not 000)
-        hardware.updateConditionFlag(to: .zro)
-
-        // Set the program counter to the default starting location
-        hardware.updateRegister(.pc, with: Constant.pcStart)
-
+        // Start the LC-3 machine
         hardware.isRunning = true
 
         while hardware.isRunning {
             let instruction = hardware.readNextInstruction()
 
-            switch instruction.opcode {
+            switch try instruction.opcode {
             case .br:
                 try BR.execute(instruction)
             case .add:
@@ -72,22 +71,7 @@ struct LC3VM: AsyncParsableCommand {
             }
         }
 
+        // Restore input buffering
         restore_input_buffering()
     }
 }
-
-/// The error type for the LC3 virtual machine.
-enum LC3VMError: Error {
-    case badOpcode
-    case invalidInstruction
-    case invalidRegister
-    case invalidOpcode
-    case unableToReadImageFile
-}
-
-/// The LC-3 constant values.
-enum Constant {
-    static let memorySize = 1 << 16
-    static let registerCount = 10
-    static let pcStart: UInt16 = 0x3000 // Default program counter location
-}

Sources/CHelpers.swift → Sources/LC3VMCore/CHelpers.swift

@@ -13,20 +13,20 @@ import Foundation
 var original_tio = termios()
 
 @MainActor
-func disable_input_buffering() {
+public func disable_input_buffering() {
     tcgetattr(STDIN_FILENO, &original_tio)
     var new_tio = original_tio
     new_tio.c_lflag = UInt(Int32(new_tio.c_lflag) & ~ICANON & ~ECHO)
     tcsetattr(STDIN_FILENO, TCSANOW, &new_tio)
 }
 
 @MainActor
-func restore_input_buffering() {
+public func restore_input_buffering() {
     tcsetattr(STDIN_FILENO, TCSANOW, &original_tio)
 }
 
 @MainActor
-func handle_interrupt(_: Int32) {
+public func handle_interrupt(_: Int32) {
     restore_input_buffering()
     print("")
     exit(-2)