Optimize startup time using TCP sockets instead of junixsocket and `t…

…put` instead of jline (#4009)

The `AFUNIXServerSocket` library we are using seems to cause an extra
~500ms latency launching the Mill client, and also causes the Graal
native-image to crash during generation.

* Using TCP sockets seems to cut the launch overhead down from ~1000ms
to ~500ms, and opens up the possibility of using native-image to cut it
further.

* Using localhost TCP sockets seems secure as far as I can tell
https://security.stackexchange.com/questions/108544/once-established-are-sockets-on-localhost-secure

* The JVM also ships with `UnixDomainSocketAddress` starting from JDK 17
that we can consider using, either by requiring JDK17 or by
conditionally using it based on JDK version. But for now I want to keep
supporting JDK11 and don't want to split the code paths, so we'll hold
off on this for now

`jline.terminal.Terminal.getSize` also adds a few hundred milliseconds,
so we instead use the same `tput` command that Ammonite uses which takes
<10ms.

* On windows where `tput` isn't support, it falls back to 100 cols,
which I reduced it down from 120 to hopefully avoid line wrapping in
most terminals while still providing a decent experience

Together these two changes cuts down the time taken for a hot `time
./mill version` on the Mill repo from ~1.05s to ~0.24s

integration/feature/full-run-logs/src/FullRunLogsTests.scala

@@ -32,17 +32,17 @@ object FullRunLogsTests extends UtestIntegrationTestSuite {
       assert("\\[\\d+\\] <h1>hello</h1>".r.matches(res.out))
 
       val expectedErrorRegex =
-        s"""==================================================== run --text hello ================================================
-           |======================================================================================================================
+        s"""========================================== run --text hello ======================================
+           |==================================================================================================
            |[build.mill-<digits>/<digits>] compile
            |[build.mill-<digits>] [info] compiling 1 Scala source to ${tester.workspacePath}/out/mill-build/compile.dest/classes ...
            |[build.mill-<digits>] [info] done compiling
            |[<digits>/<digits>] compile
            |[<digits>] [info] compiling 1 Java source to ${tester.workspacePath}/out/compile.dest/classes ...
            |[<digits>] [info] done compiling
            |[<digits>/<digits>] run
-           |[<digits>/<digits>] ============================================ run --text hello ============================================<digits>s
-           |======================================================================================================================"""
+           |[<digits>/<digits>] ================================== run --text hello ==================================<digits>s
+           |=================================================================================================="""
           .stripMargin
           .replaceAll("(\r\n)|\r", "\n")
           .replace('\\', '/')

main/api/src/mill/api/ClassLoader.scala

@@ -5,7 +5,7 @@ import java.net.{URL, URLClassLoader}
 import java.nio.file.{FileAlreadyExistsException, FileSystemException}
 
 import mill.java9rtexport.Export
-import scala.util.{Properties, Try}
+import scala.util.Properties
 
 /**
  * Utilities for creating classloaders for running compiled Java/Scala code in
@@ -90,7 +90,9 @@ object ClassLoader {
         )
         retry {
           try os.copy(os.Path(Export.rt()), java90rtJar, createFolders = true)
-          catch { case e: FileAlreadyExistsException => /* someone else already did this */}
+          catch {
+            case e: FileAlreadyExistsException => /* someone else already did this */
+          }
         }
       }
       urls :+ java90rtJar.toIO.toURI().toURL()

main/client/src/mill/main/client/ProxyStream.java

@@ -164,9 +164,6 @@ public void run() {
               }
             }
           }
-        } catch (org.newsclub.net.unix.ConnectionResetSocketException e) {
-          // This happens when you run mill shutdown and the server exits gracefully
-          break;
         } catch (IOException e) {
           // This happens when the upstream pipe was closed
           break;

main/client/src/mill/main/client/ServerFiles.java

@@ -22,6 +22,11 @@ public class ServerFiles {
    */
   public static final String processLock = "processLock";
 
+  /**
+   * The port used to connect between server and client
+   */
+  public static final String socketPort = "socketPort";
+
   /**
    * The pipe by which the client snd server exchange IO
    *

main/client/src/mill/main/client/ServerLauncher.java

@@ -2,7 +2,6 @@
 
 import static mill.main.client.OutFiles.*;
 
-import java.io.File;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.PrintStream;
@@ -13,8 +12,6 @@
 import java.util.Map;
 import mill.main.client.lock.Locks;
 import mill.main.client.lock.TryLocked;
-import org.newsclub.net.unix.AFUNIXSocket;
-import org.newsclub.net.unix.AFUNIXSocketAddress;
 
 /**
  * Client side code that interacts with `Server.scala` in order to launch a generic
@@ -133,15 +130,13 @@ int run(Path serverDir, boolean setJnaNoSys, Locks locks) throws Exception {
 
     while (locks.processLock.probe()) Thread.sleep(3);
 
-    String socketName = ServerFiles.pipe(serverDir.toString());
-    AFUNIXSocketAddress addr = AFUNIXSocketAddress.of(new File(socketName));
-
     long retryStart = System.currentTimeMillis();
     Socket ioSocket = null;
     Throwable socketThrowable = null;
     while (ioSocket == null && System.currentTimeMillis() - retryStart < serverInitWaitMillis) {
       try {
-        ioSocket = AFUNIXSocket.connectTo(addr);
+        int port = Integer.parseInt(Files.readString(serverDir.resolve(ServerFiles.socketPort)));
+        ioSocket = new java.net.Socket("127.0.0.1", port);
       } catch (Throwable e) {
         socketThrowable = e;
         Thread.sleep(10);

main/package.mill

@@ -138,7 +138,6 @@ object `package` extends RootModule with build.MillStableScalaModule with BuildI
   object client extends build.MillPublishJavaModule with BuildInfo {
     def buildInfoPackageName = "mill.main.client"
     def buildInfoMembers = Seq(BuildInfo.Value("millVersion", build.millVersion(), "Mill version."))
-    def ivyDeps = Agg(build.Deps.junixsocket, build.Deps.jline)
 
     object test extends JavaModuleTests with TestModule.Junit4 {
       def ivyDeps = Agg(build.Deps.junitInterface, build.Deps.commonsIo)

main/server/src/mill/main/server/Server.scala

@@ -1,10 +1,8 @@
 package mill.main.server
 
 import java.io._
-import java.net.Socket
+import java.net.{InetAddress, Socket}
 import scala.jdk.CollectionConverters._
-import org.newsclub.net.unix.AFUNIXServerSocket
-import org.newsclub.net.unix.AFUNIXSocketAddress
 import mill.main.client._
 import mill.api.SystemStreams
 import mill.main.client.ProxyStream.Output
@@ -48,7 +46,8 @@ abstract class Server[T](
 
         while (
           running && {
-            val serverSocket = bindSocket()
+            val serverSocket = new java.net.ServerSocket(0, 0, InetAddress.getByName(null))
+            os.write.over(serverDir / ServerFiles.socketPort, serverSocket.getLocalPort.toString)
             try
               interruptWithTimeout(() => serverSocket.close(), () => serverSocket.accept()) match {
                 case None => false
@@ -69,17 +68,6 @@ abstract class Server[T](
     finally exitServer()
   }
 
-  def bindSocket(): AFUNIXServerSocket = {
-    val socketPath = os.Path(ServerFiles.pipe(serverDir.toString()))
-    os.remove.all(socketPath)
-
-    val relFile = socketPath.relativeTo(os.pwd).toNIO.toFile
-    serverLog("listening on socket " + relFile + " " + os.pwd)
-    // Use relative path because otherwise the full path might be too long for the socket API
-    val addr = AFUNIXSocketAddress.of(relFile)
-    AFUNIXServerSocket.bindOn(addr)
-  }
-
   def proxyInputStreamThroughPumper(in: InputStream): PipedInputStream = {
     val pipedInput = new PipedInputStream()
     val pipedOutput = new PipedOutputStream()

main/util/src/mill/util/PromptLoggerUtil.scala

@@ -2,8 +2,8 @@ package mill.util
 
 private object PromptLoggerUtil {
 
-  private[mill] val defaultTermWidth = 119
-  private[mill] val defaultTermHeight = 50
+  private[mill] val defaultTermWidth = 99
+  private[mill] val defaultTermHeight = 25
 
   /**
    * How often to update the multiline status prompt on the terminal.

main/util/test/src/mill/util/PromptLoggerTests.scala

@@ -78,8 +78,8 @@ object PromptLoggerTests extends TestSuite {
         promptLogger.close()
 
         check(promptLogger, baos, width = 999 /*log file has no line wrapping*/ )(
-          "========================================================== TITLE =====================================================",
-          "======================================================================================================================",
+          "================================================ TITLE ===========================================",
+          "==================================================================================================",
           // Make sure that the first time a prefix is reported,
           // we print the verbose prefix along with the ticker string
           "[1/456] my-task",
@@ -89,17 +89,17 @@ object PromptLoggerTests extends TestSuite {
           // the double space prefix (since it's non-interactive and we don't need space for a cursor),
           // the time elapsed, the reported title and ticker, the list of active tickers, followed by the
           // footer
-          "[123/456] ================================================ TITLE ================================================= 10s",
+          "[123/456] ====================================== TITLE ======================================= 10s",
           "[1] my-task 10s",
-          "======================================================================================================================",
+          "==================================================================================================",
           "[1] WORLD",
           // Calling `refreshPrompt()` after closing the ticker shows the prompt without
           // the ticker in the list, with an updated time elapsed
-          "[123/456] ================================================ TITLE ================================================= 20s",
-          "======================================================================================================================",
+          "[123/456] ====================================== TITLE ======================================= 20s",
+          "==================================================================================================",
           // Closing the prompt prints the prompt one last time with an updated time elapsed
-          "[123/456] ================================================ TITLE ================================================= 30s",
-          "======================================================================================================================",
+          "[123/456] ====================================== TITLE ======================================= 30s",
+          "==================================================================================================",
           ""
         )
       }

runner/client/src/mill/runner/client/MillProcessLauncher.java

@@ -12,8 +12,6 @@
 import mill.main.client.EnvVars;
 import mill.main.client.ServerFiles;
 import mill.main.client.Util;
-import org.jline.terminal.Terminal;
-import org.jline.terminal.TerminalBuilder;
 
 public class MillProcessLauncher {
 
@@ -195,16 +193,36 @@ static List<String> readMillJvmOpts() {
     return Util.readOptsFileLines(millJvmOptsFile());
   }
 
+  static int getTerminalDim(String s) throws Exception {
+    Process proc = new ProcessBuilder()
+        .command("tput", s)
+        .redirectOutput(ProcessBuilder.Redirect.PIPE)
+        .redirectInput(ProcessBuilder.Redirect.INHERIT)
+        .redirectError(ProcessBuilder.Redirect.PIPE)
+        .start();
+    proc.waitFor();
+    return Integer.parseInt(new String(proc.getInputStream().readAllBytes()).trim());
+  }
+
+  static void writeTerminalDims(Path serverDir) throws Exception {
+    String str;
+    try {
+      str = java.lang.System.console() == null
+          ? "0 0"
+          : getTerminalDim("cols") + " " + getTerminalDim("lines");
+    } catch (Exception e) {
+      str = "0 0";
+    }
+    Files.write(serverDir.resolve(ServerFiles.terminfo), str.getBytes());
+  }
+
   public static void runTermInfoThread(Path serverDir) throws Exception {
-    Terminal term = TerminalBuilder.builder().dumb(true).build();
+
     Thread termInfoPropagatorThread = new Thread(
         () -> {
           try {
             while (true) {
-              Files.write(
-                  serverDir.resolve(ServerFiles.terminfo),
-                  (term.getWidth() + " " + term.getHeight()).getBytes());
-
+              writeTerminalDims(serverDir);
               Thread.sleep(100);
             }
           } catch (Exception e) {