src/Pure/System/isabelle_system.scala

 /*  Title:      Pure/System/isabelle_system.scala
     Author:     Makarius
 
-Fundamental Isabelle system environment: quasi-static module with
-optional init operation.
+Miscellaneous Isabelle system operations.
 */
 
 package isabelle
 
 
 import java.io.{File => JFile, IOException}
 import java.nio.file.{Path => JPath, Files, SimpleFileVisitor, FileVisitResult,
   StandardCopyOption, FileSystemException}
 import java.nio.file.attribute.BasicFileAttributes
 
-import scala.jdk.CollectionConverters._
-
 
 object Isabelle_System
 {
-  /** bootstrap information **/
-
-  def jdk_home(): String =
-  {
-    val java_home = System.getProperty("java.home", "")
-    val home = new JFile(java_home)
-    val parent = home.getParent
-    if (home.getName == "jre" && parent != null &&
-        (new JFile(new JFile(parent, "bin"), "javac")).exists) parent
-    else java_home
-  }
-
-  def bootstrap_directory(
-    preference: String, envar: String, property: String, description: String): String =
-  {
-    val value =
-      proper_string(preference) orElse  // explicit argument
-      proper_string(System.getenv(envar)) orElse  // e.g. inherited from running isabelle tool
-      proper_string(System.getProperty(property)) getOrElse  // e.g. via JVM application boot process
-      error("Unknown " + description + " directory")
-
-    if ((new JFile(value)).isDirectory) value
-    else error("Bad " + description + " directory " + quote(value))
-  }
-
-
-
-  /** implicit settings environment **/
-
-  abstract class Service
-
-  @volatile private var _settings: Option[Map[String, String]] = None
-  @volatile private var _services: Option[List[Class[Service]]] = None
-
-  def settings(): Map[String, String] =
-  {
-    if (_settings.isEmpty) init()  // unsynchronized check
-    _settings.get
-  }
-
-  def services(): List[Class[Service]] =
-  {
-    if (_services.isEmpty) init()  // unsynchronized check
-    _services.get
-  }
+  /* services */
+
+  type Service = Isabelle_Env.Service
+
+  def services(): List[Class[Service]] = Isabelle_Env.services()
 
   def make_services[C](c: Class[C]): List[C] =
     for { c1 <- services() if Library.is_subclass(c1, c) }
       yield c1.getDeclaredConstructor().newInstance().asInstanceOf[C]
 
-  def init(isabelle_root: String = "", cygwin_root: String = ""): Unit = synchronized
-  {
-    if (_settings.isEmpty || _services.isEmpty) {
-      val isabelle_root1 =
-        bootstrap_directory(isabelle_root, "ISABELLE_ROOT", "isabelle.root", "Isabelle root")
-
-      val cygwin_root1 =
-        if (Platform.is_windows)
-          bootstrap_directory(cygwin_root, "CYGWIN_ROOT", "cygwin.root", "Cygwin root")
-        else ""
-
-      if (Platform.is_windows) Cygwin.init(isabelle_root1, cygwin_root1)
-
-      def set_cygwin_root(): Unit =
-      {
-        if (Platform.is_windows)
-          _settings = Some(_settings.getOrElse(Map.empty) + ("CYGWIN_ROOT" -> cygwin_root1))
-      }
-
-      set_cygwin_root()
-
-      def default(env: Map[String, String], entry: (String, String)): Map[String, String] =
-        if (env.isDefinedAt(entry._1) || entry._2 == "") env
-        else env + entry
-
-      val env =
-      {
-        val temp_windows =
-        {
-          val temp = if (Platform.is_windows) System.getenv("TEMP") else null
-          if (temp != null && temp.contains('\\')) temp else ""
-        }
-        val user_home = System.getProperty("user.home", "")
-        val isabelle_app = System.getProperty("isabelle.app", "")
-
-        default(
-          default(
-            default(sys.env + ("ISABELLE_JDK_HOME" -> File.standard_path(jdk_home())),
-              "TEMP_WINDOWS" -> temp_windows),
-            "HOME" -> user_home),
-          "ISABELLE_APP" -> isabelle_app)
-      }
-
-      val settings =
-      {
-        val dump = JFile.createTempFile("settings", null)
-        dump.deleteOnExit
-        try {
-          val cmd1 =
-            if (Platform.is_windows)
-              List(cygwin_root1 + "\\bin\\bash", "-l",
-                File.standard_path(isabelle_root1 + "\\bin\\isabelle"))
-            else
-              List(isabelle_root1 + "/bin/isabelle")
-          val cmd = cmd1 ::: List("getenv", "-d", dump.toString)
-
-          val (output, rc) = process_output(process(cmd, env = env, redirect = true))
-          if (rc != 0) error(output)
-
-          val entries =
-            space_explode('\u0000', File.read(dump)).flatMap(
-              {
-                case Properties.Eq(a, b) => Some(a -> b)
-                case s => if (s.isEmpty || s.startsWith("=")) None else Some(s -> "")
-              }).toMap
-          entries + ("PATH" -> entries("PATH_JVM")) - "PATH_JVM"
-        }
-        finally { dump.delete }
-      }
-      _settings = Some(settings)
-      set_cygwin_root()
-
-      val variable = "ISABELLE_SCALA_SERVICES"
-      val services =
-        for (name <- space_explode(':', settings.getOrElse(variable, getenv_error(variable))))
-        yield {
-          def err(msg: String): Nothing =
-            error("Bad entry " + quote(name) + " in " + variable + "\n" + msg)
-          try { Class.forName(name).asInstanceOf[Class[Service]] }
-          catch {
-            case _: ClassNotFoundException => err("Class not found")
-            case exn: Throwable => err(Exn.message(exn))
-          }
-        }
-      _services = Some(services)
-    }
-  }
-
-
-  /* getenv -- dynamic process environment */
-
-  private def getenv_error(name: String): Nothing =
-    error("Undefined Isabelle environment variable: " + quote(name))
+
+  /* settings */
+
+  def settings(): Map[String, String] = Isabelle_Env.settings()
 
   def getenv(name: String, env: Map[String, String] = settings()): String =
     env.getOrElse(name, "")
 
   def getenv_strict(name: String, env: Map[String, String] = settings()): String =

 
 
 
   /** external processes **/
 
-  /* raw process */
-
-  def process(command_line: List[String],
-    cwd: JFile = null,
-    env: Map[String, String] = settings(),
-    redirect: Boolean = false): Process =
-  {
-    val proc = new ProcessBuilder
-
-    // fragile on Windows:
-    // see https://docs.microsoft.com/en-us/cpp/cpp/main-function-command-line-args?view=msvc-160
-    proc.command(command_line.asJava)
-
-    if (cwd != null) proc.directory(cwd)
-    if (env != null) {
-      proc.environment.clear()
-      for ((x, y) <- env) proc.environment.put(x, y)
-    }
-    proc.redirectErrorStream(redirect)
-    proc.start
-  }
-
-  def process_output(proc: Process): (String, Int) =
-  {
-    proc.getOutputStream.close()
-
-    val output = File.read_stream(proc.getInputStream)
-    val rc =
-      try { proc.waitFor }
-      finally {
-        proc.getInputStream.close()
-        proc.getErrorStream.close()
-        proc.destroy()
-        Exn.Interrupt.dispose()
-      }
-    (output, rc)
-  }
-
-  def process_signal(group_pid: String, signal: String = "0"): Boolean =
-  {
-    val bash =
-      if (Platform.is_windows) List(cygwin_root() + "\\bin\\bash.exe")
-      else List("/usr/bin/env", "bash")
-    val (_, rc) = process_output(process(bash ::: List("-c", "kill -" + signal + " -" + group_pid)))
-    rc == 0
-  }
-
-
   /* GNU bash */
 
   def bash(script: String,
     cwd: JFile = null,
     env: Map[String, String] = settings(),