src/Pure/System/isabelle_process.scala
author wenzelm
Wed Sep 21 20:35:50 2011 +0200 (2011-09-21 ago)
changeset 45027 f459e93a038e
parent 44775 27930cf6f0f7
child 45055 55274f7e306b
permissions -rw-r--r--
more abstract wrapping of fifos as System_Channel;
     1 /*  Title:      Pure/System/isabelle_process.scala
     2     Author:     Makarius
     3     Options:    :folding=explicit:collapseFolds=1:
     4 
     5 Isabelle process management -- always reactive due to multi-threaded I/O.
     6 */
     7 
     8 package isabelle
     9 
    10 import java.lang.System
    11 import java.util.concurrent.LinkedBlockingQueue
    12 import java.io.{BufferedReader, BufferedWriter, InputStreamReader, OutputStreamWriter,
    13   InputStream, OutputStream, BufferedOutputStream, IOException}
    14 
    15 import scala.actors.Actor
    16 import Actor._
    17 
    18 
    19 object Isabelle_Process
    20 {
    21   /* results */
    22 
    23   object Kind
    24   {
    25     val message_markup = Map(
    26       ('A' : Int) -> Markup.INIT,
    27       ('B' : Int) -> Markup.STATUS,
    28       ('C' : Int) -> Markup.REPORT,
    29       ('D' : Int) -> Markup.WRITELN,
    30       ('E' : Int) -> Markup.TRACING,
    31       ('F' : Int) -> Markup.WARNING,
    32       ('G' : Int) -> Markup.ERROR,
    33       ('H' : Int) -> Markup.RAW)
    34   }
    35 
    36   sealed abstract class Message
    37 
    38   class Input(name: String, args: List[String]) extends Message
    39   {
    40     override def toString: String =
    41       XML.Elem(Markup(Markup.PROVER_COMMAND, List((Markup.NAME, name))),
    42         args.map(s =>
    43           List(XML.Text("\n"), XML.elem(Markup.PROVER_ARG, YXML.parse_body(s)))).flatten).toString
    44   }
    45 
    46   class Result(val message: XML.Elem) extends Message
    47   {
    48     def kind: String = message.markup.name
    49     def properties: Properties.T = message.markup.properties
    50     def body: XML.Body = message.body
    51 
    52     def is_init = kind == Markup.INIT
    53     def is_exit = kind == Markup.EXIT
    54     def is_stdout = kind == Markup.STDOUT
    55     def is_system = kind == Markup.SYSTEM
    56     def is_status = kind == Markup.STATUS
    57     def is_report = kind == Markup.REPORT
    58     def is_raw = kind == Markup.RAW
    59     def is_ready = Isar_Document.is_ready(message)
    60     def is_syslog = is_init || is_exit || is_system || is_ready
    61 
    62     override def toString: String =
    63     {
    64       val res =
    65         if (is_status || is_report) message.body.map(_.toString).mkString
    66         else if (is_raw) "..."
    67         else Pretty.string_of(message.body)
    68       if (properties.isEmpty)
    69         kind.toString + " [[" + res + "]]"
    70       else
    71         kind.toString + " " +
    72           (for ((x, y) <- properties) yield x + "=" + y).mkString("{", ",", "}") + " [[" + res + "]]"
    73     }
    74   }
    75 }
    76 
    77 
    78 class Isabelle_Process(timeout: Time, receiver: Isabelle_Process.Message => Unit, args: String*)
    79 {
    80   import Isabelle_Process._
    81 
    82 
    83   /* demo constructor */
    84 
    85   def this(args: String*) = this(Time.seconds(10), Console.println(_), args: _*)
    86 
    87 
    88   /* results */
    89 
    90   private def system_result(text: String)
    91   {
    92     receiver(new Result(XML.Elem(Markup(Markup.SYSTEM, Nil), List(XML.Text(text)))))
    93   }
    94 
    95   private val xml_cache = new XML.Cache()
    96 
    97   private def put_result(kind: String, props: Properties.T, body: XML.Body)
    98   {
    99     if (kind == Markup.INIT) system_channel.accepted()
   100     if (kind == Markup.RAW)
   101       receiver(new Result(XML.Elem(Markup(kind, props), body)))
   102     else {
   103       val msg = XML.Elem(Markup(kind, props), Isar_Document.clean_message(body))
   104       receiver(new Result(xml_cache.cache_tree(msg).asInstanceOf[XML.Elem]))
   105     }
   106   }
   107 
   108   private def put_result(kind: String, text: String)
   109   {
   110     put_result(kind, Nil, List(XML.Text(Symbol.decode(text))))
   111   }
   112 
   113 
   114   /* input actors */
   115 
   116   private case class Input_Text(text: String)
   117   private case class Input_Chunks(chunks: List[Array[Byte]])
   118 
   119   private case object Close
   120   private def close(p: (Thread, Actor))
   121   {
   122     if (p != null && p._1.isAlive) {
   123       p._2 ! Close
   124       p._1.join
   125     }
   126   }
   127 
   128   @volatile private var standard_input: (Thread, Actor) = null
   129   @volatile private var command_input: (Thread, Actor) = null
   130 
   131 
   132   /** process manager **/
   133 
   134   private val system_channel = System_Channel()
   135 
   136   private val process =
   137     try {
   138       val cmdline =
   139         Isabelle_System.getenv_strict("ISABELLE_PROCESS") ::
   140           (system_channel.isabelle_args ::: args.toList)
   141       new Isabelle_System.Managed_Process(true, cmdline: _*)
   142     }
   143     catch { case e: IOException => system_channel.accepted(); throw(e) }
   144 
   145   val process_result =
   146     Simple_Thread.future("process_result") { process.join }
   147 
   148   private def terminate_process()
   149   {
   150     try { process.terminate }
   151     catch { case e: IOException => system_result("Failed to terminate Isabelle: " + e.getMessage) }
   152   }
   153 
   154   private val process_manager = Simple_Thread.fork("process_manager")
   155   {
   156     val (startup_failed, startup_output) =
   157     {
   158       val expired = System.currentTimeMillis() + timeout.ms
   159       val result = new StringBuilder(100)
   160 
   161       var finished: Option[Boolean] = None
   162       while (finished.isEmpty && System.currentTimeMillis() <= expired) {
   163         while (finished.isEmpty && process.stdout.ready) {
   164           val c = process.stdout.read
   165           if (c == 2) finished = Some(true)
   166           else result += c.toChar
   167         }
   168         if (process_result.is_finished) finished = Some(false)
   169         else Thread.sleep(10)
   170       }
   171       (finished.isEmpty || !finished.get, result.toString.trim)
   172     }
   173     system_result(startup_output)
   174 
   175     if (startup_failed) {
   176       put_result(Markup.EXIT, "Return code: 127")
   177       process.stdin.close
   178       Thread.sleep(300)
   179       terminate_process()
   180       process_result.join
   181     }
   182     else {
   183       val (command_stream, message_stream) = system_channel.rendezvous()
   184 
   185       standard_input = stdin_actor()
   186       val stdout = stdout_actor()
   187       command_input = input_actor(command_stream)
   188       val message = message_actor(message_stream)
   189 
   190       val rc = process_result.join
   191       system_result("process terminated")
   192       for ((thread, _) <- List(standard_input, stdout, command_input, message)) thread.join
   193       system_result("process_manager terminated")
   194       put_result(Markup.EXIT, "Return code: " + rc.toString)
   195     }
   196     system_channel.accepted()
   197   }
   198 
   199 
   200   /* management methods */
   201 
   202   def join() { process_manager.join() }
   203 
   204   def terminate()
   205   {
   206     close()
   207     system_result("Terminating Isabelle process")
   208     terminate_process()
   209   }
   210 
   211 
   212 
   213   /** stream actors **/
   214 
   215   /* raw stdin */
   216 
   217   private def stdin_actor(): (Thread, Actor) =
   218   {
   219     val name = "standard_input"
   220     Simple_Thread.actor(name) {
   221       var finished = false
   222       while (!finished) {
   223         try {
   224           //{{{
   225           receive {
   226             case Input_Text(text) =>
   227               process.stdin.write(text)
   228               process.stdin.flush
   229             case Close =>
   230               process.stdin.close
   231               finished = true
   232             case bad => System.err.println(name + ": ignoring bad message " + bad)
   233           }
   234           //}}}
   235         }
   236         catch { case e: IOException => system_result(name + ": " + e.getMessage) }
   237       }
   238       system_result(name + " terminated")
   239     }
   240   }
   241 
   242 
   243   /* raw stdout */
   244 
   245   private def stdout_actor(): (Thread, Actor) =
   246   {
   247     val name = "standard_output"
   248     Simple_Thread.actor(name) {
   249       var result = new StringBuilder(100)
   250 
   251       var finished = false
   252       while (!finished) {
   253         try {
   254           //{{{
   255           var c = -1
   256           var done = false
   257           while (!done && (result.length == 0 || process.stdout.ready)) {
   258             c = process.stdout.read
   259             if (c >= 0) result.append(c.asInstanceOf[Char])
   260             else done = true
   261           }
   262           if (result.length > 0) {
   263             put_result(Markup.STDOUT, result.toString)
   264             result.length = 0
   265           }
   266           else {
   267             process.stdout.close
   268             finished = true
   269           }
   270           //}}}
   271         }
   272         catch { case e: IOException => system_result(name + ": " + e.getMessage) }
   273       }
   274       system_result(name + " terminated")
   275     }
   276   }
   277 
   278 
   279   /* command input */
   280 
   281   private def input_actor(raw_stream: OutputStream): (Thread, Actor) =
   282   {
   283     val name = "command_input"
   284     Simple_Thread.actor(name) {
   285       val stream = new BufferedOutputStream(raw_stream)
   286       var finished = false
   287       while (!finished) {
   288         try {
   289           //{{{
   290           receive {
   291             case Input_Chunks(chunks) =>
   292               stream.write(Standard_System.string_bytes(
   293                   chunks.map(_.length).mkString("", ",", "\n")));
   294               chunks.foreach(stream.write(_));
   295               stream.flush
   296             case Close =>
   297               stream.close
   298               finished = true
   299             case bad => System.err.println(name + ": ignoring bad message " + bad)
   300           }
   301           //}}}
   302         }
   303         catch { case e: IOException => system_result(name + ": " + e.getMessage) }
   304       }
   305       system_result(name + " terminated")
   306     }
   307   }
   308 
   309 
   310   /* message output */
   311 
   312   private def message_actor(stream: InputStream): (Thread, Actor) =
   313   {
   314     class EOF extends Exception
   315     class Protocol_Error(msg: String) extends Exception(msg)
   316 
   317     val name = "message_output"
   318     Simple_Thread.actor(name) {
   319       val default_buffer = new Array[Byte](65536)
   320       var c = -1
   321 
   322       def read_chunk(decode: Boolean): XML.Body =
   323       {
   324         //{{{
   325         // chunk size
   326         var n = 0
   327         c = stream.read
   328         if (c == -1) throw new EOF
   329         while (48 <= c && c <= 57) {
   330           n = 10 * n + (c - 48)
   331           c = stream.read
   332         }
   333         if (c != 10) throw new Protocol_Error("bad message chunk header")
   334 
   335         // chunk content
   336         val buf =
   337           if (n <= default_buffer.size) default_buffer
   338           else new Array[Byte](n)
   339 
   340         var i = 0
   341         var m = 0
   342         do {
   343           m = stream.read(buf, i, n - i)
   344           if (m != -1) i += m
   345         } while (m != -1 && n > i)
   346 
   347         if (i != n) throw new Protocol_Error("bad message chunk content")
   348 
   349         if (decode)
   350           YXML.parse_body_failsafe(Standard_System.decode_chars(Symbol.decode, buf, 0, n))
   351         else List(XML.Text(Standard_System.decode_chars(s => s, buf, 0, n).toString))
   352         //}}}
   353       }
   354 
   355       do {
   356         try {
   357           val header = read_chunk(true)
   358           header match {
   359             case List(XML.Elem(Markup(name, props), Nil))
   360                 if name.size == 1 && Kind.message_markup.isDefinedAt(name(0)) =>
   361               val kind = Kind.message_markup(name(0))
   362               val body = read_chunk(kind != Markup.RAW)
   363               put_result(kind, props, body)
   364             case _ =>
   365               read_chunk(false)
   366               throw new Protocol_Error("bad header: " + header.toString)
   367           }
   368         }
   369         catch {
   370           case e: IOException => system_result("Cannot read message:\n" + e.getMessage)
   371           case e: Protocol_Error => system_result("Malformed message:\n" + e.getMessage)
   372           case _: EOF =>
   373         }
   374       } while (c != -1)
   375       stream.close
   376 
   377       system_result(name + " terminated")
   378     }
   379   }
   380 
   381 
   382   /** main methods **/
   383 
   384   def input_raw(text: String): Unit = standard_input._2 ! Input_Text(text)
   385 
   386   def input_bytes(name: String, args: Array[Byte]*): Unit =
   387     command_input._2 ! Input_Chunks(Standard_System.string_bytes(name) :: args.toList)
   388 
   389   def input(name: String, args: String*): Unit =
   390   {
   391     receiver(new Input(name, args.toList))
   392     input_bytes(name, args.map(Standard_System.string_bytes): _*)
   393   }
   394 
   395   def close(): Unit = { close(command_input); close(standard_input) }
   396 }