Remove the dependency on libreadline

Package.swift

@@ -22,7 +22,6 @@ let appleOS = false
 
 let useLocalDependencies = Context.environment["SWIFTCI_USE_LOCAL_DEPS"] != nil
 let useLLBuildFramework = Context.environment["SWIFTBUILD_LLBUILD_FWK"] != nil
-let readlinePackage = !appleOS ? "readline" : nil
 
 let swiftSettings: [SwiftSetting] = [
     // Upcoming Swift 6.0 features
@@ -162,7 +161,6 @@ let package = Package(
             dependencies: [
                 "SWBCSupport",
                 "SWBLibc",
-                .target(name: "readline", condition: .when(platforms: [.linux])),
                 .product(name: "ArgumentParser", package: "swift-argument-parser"),
                 .product(name: "Crypto", package: "swift-crypto", condition: .when(platforms: [.linux, .android])),
                 .product(name: "SystemPackage", package: "swift-system", condition: .when(platforms: [.linux, .android, .windows])),
@@ -343,17 +341,6 @@ let package = Package(
             dependencies: ["SwiftBuild", "SWBTestSupport", "SwiftBuildTestSupport"],
             swiftSettings: swiftSettings),
 
-        // System libraries
-        .systemLibrary(
-            name: "readline",
-            path: "Packages/Sources/readline",
-            pkgConfig: readlinePackage,
-            providers: [
-                .apt(["libreadline-dev"]),
-                .yum(["readline-devel"]),
-            ]
-        ),
-
         // Commands
         .plugin(
             name: "launch-xcode",

Sources/SWBCSupport/SWBCSupport.h

@@ -19,15 +19,6 @@
 #include <TargetConditionals.h>
 #endif
 
-#ifndef __APPLE__
-// Re-exported from readline
-char *readline(const char *);
-int add_history(const char *);
-int read_history(const char *);
-int write_history(const char *);
-int history_truncate_file(const char *, int);
-#endif
-
 #include "CLibclang.h"
 #include "CLibRemarksHelper.h"
 #include "PluginAPI.h"

Sources/SwiftBuild/SWBTerminal.swift

@@ -15,27 +15,19 @@ import SWBUtil
 
 import Foundation
 
-let kHistoryFilePath = "~/.swbuild_history"
-let kMaxHistoryLines = 100
-
 func swbuild_handle_command_result(result: SWBServiceConsoleResult)  {
     print(result.output, terminator: "")
 }
 
 /// Process a command line.
 ///
 /// - returns: True if the console should continue handling commands, otherwise the console should quit.
-func swbuild_process_command(console: SWBBuildServiceConsole, command: String, historyPath: String) async -> (shouldContinue: Bool, success: Bool) {
+func swbuild_process_command(console: SWBBuildServiceConsole, command: String) async -> (shouldContinue: Bool, success: Bool) {
     // Ignore empty commands.
     if command.isEmpty {
         return (true, true)
     }
 
-    // Add the line to the history.
-    swb_add_history(command)
-    swb_write_history(historyPath)
-    swb_history_truncate_file(historyPath, kMaxHistoryLines)
-
     // Process the line.
     let (result, success) = await console.sendCommandString(command)
     swbuild_handle_command_result(result: result)
@@ -71,24 +63,20 @@ func swbuild_repl() async throws -> Bool {
     // Save the terminal attributes (and restore them and exit).
     return try await withTerminalAttributes { terminalAttributes in
         return try await withServiceConsole { console in
-            let historyPath = (kHistoryFilePath as NSString).expandingTildeInPath
-
-            // Read in the command history.
-            swb_read_history(historyPath)
-
             // Disable echo, after all readline initialization is done.
             terminalAttributes.disableEcho()
 
             var ok = true
             var shouldContinue = true
             while shouldContinue {
-                guard let line = swb_readline("swbuild> ") else {
+                print("swbuild> ", terminator: "")
+                guard let line = readLine() else {
                     // If we received the EOF then exit.
                     print()
                     break
                 }
 
-                (shouldContinue, ok) = await swbuild_process_command(console: console, command: line, historyPath: historyPath)
+                (shouldContinue, ok) = await swbuild_process_command(console: console, command: line)
             }
 
             return ok