src/Pure/System/isabelle_process.scala
author wenzelm
Tue Sep 06 11:18:19 2011 +0200 (2011-09-06 ago)
changeset 44733 329320fc88df
parent 44732 c58b69d888ac
child 44775 27930cf6f0f7
permissions -rw-r--r--
buffer prover messages to prevent overloading of session_actor input channel -- which is critical due to synchronous messages wrt. GUI thread;
     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) rm_fifos()
   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 in_fifo = Isabelle_System.mk_fifo()
   135   private val out_fifo = Isabelle_System.mk_fifo()
   136   private def rm_fifos() { Isabelle_System.rm_fifo(in_fifo); Isabelle_System.rm_fifo(out_fifo) }
   137 
   138   private val process =
   139     try {
   140       val cmdline =
   141         List(Isabelle_System.getenv_strict("ISABELLE_PROCESS"), "-W",
   142           in_fifo + ":" + out_fifo) ++ args
   143       new Isabelle_System.Managed_Process(true, cmdline: _*)
   144     }
   145     catch { case e: IOException => rm_fifos(); throw(e) }
   146 
   147   val process_result =
   148     Simple_Thread.future("process_result") { process.join }
   149 
   150   private def terminate_process()
   151   {
   152     try { process.terminate }
   153     catch { case e: IOException => system_result("Failed to terminate Isabelle: " + e.getMessage) }
   154   }
   155 
   156   private val process_manager = Simple_Thread.fork("process_manager")
   157   {
   158     val (startup_failed, startup_output) =
   159     {
   160       val expired = System.currentTimeMillis() + timeout.ms
   161       val result = new StringBuilder(100)
   162 
   163       var finished: Option[Boolean] = None
   164       while (finished.isEmpty && System.currentTimeMillis() <= expired) {
   165         while (finished.isEmpty && process.stdout.ready) {
   166           val c = process.stdout.read
   167           if (c == 2) finished = Some(true)
   168           else result += c.toChar
   169         }
   170         if (process_result.is_finished) finished = Some(false)
   171         else Thread.sleep(10)
   172       }
   173       (finished.isEmpty || !finished.get, result.toString.trim)
   174     }
   175     system_result(startup_output)
   176 
   177     if (startup_failed) {
   178       put_result(Markup.EXIT, "Return code: 127")
   179       process.stdin.close
   180       Thread.sleep(300)
   181       terminate_process()
   182       process_result.join
   183     }
   184     else {
   185       // rendezvous
   186       val command_stream = Isabelle_System.fifo_output_stream(in_fifo)
   187       val message_stream = Isabelle_System.fifo_input_stream(out_fifo)
   188 
   189       standard_input = stdin_actor()
   190       val stdout = stdout_actor()
   191       command_input = input_actor(command_stream)
   192       val message = message_actor(message_stream)
   193 
   194       val rc = process_result.join
   195       system_result("process terminated")
   196       for ((thread, _) <- List(standard_input, stdout, command_input, message)) thread.join
   197       system_result("process_manager terminated")
   198       put_result(Markup.EXIT, "Return code: " + rc.toString)
   199     }
   200     rm_fifos()
   201   }
   202 
   203 
   204   /* management methods */
   205 
   206   def join() { process_manager.join() }
   207 
   208   def interrupt()
   209   {
   210     try { process.interrupt }
   211     catch { case e: IOException => system_result("Failed to interrupt Isabelle: " + e.getMessage) }
   212   }
   213 
   214   def terminate()
   215   {
   216     close()
   217     system_result("Terminating Isabelle process")
   218     terminate_process()
   219   }
   220 
   221 
   222 
   223   /** stream actors **/
   224 
   225   /* raw stdin */
   226 
   227   private def stdin_actor(): (Thread, Actor) =
   228   {
   229     val name = "standard_input"
   230     Simple_Thread.actor(name) {
   231       var finished = false
   232       while (!finished) {
   233         try {
   234           //{{{
   235           receive {
   236             case Input_Text(text) =>
   237               process.stdin.write(text)
   238               process.stdin.flush
   239             case Close =>
   240               process.stdin.close
   241               finished = true
   242             case bad => System.err.println(name + ": ignoring bad message " + bad)
   243           }
   244           //}}}
   245         }
   246         catch { case e: IOException => system_result(name + ": " + e.getMessage) }
   247       }
   248       system_result(name + " terminated")
   249     }
   250   }
   251 
   252 
   253   /* raw stdout */
   254 
   255   private def stdout_actor(): (Thread, Actor) =
   256   {
   257     val name = "standard_output"
   258     Simple_Thread.actor(name) {
   259       var result = new StringBuilder(100)
   260 
   261       var finished = false
   262       while (!finished) {
   263         try {
   264           //{{{
   265           var c = -1
   266           var done = false
   267           while (!done && (result.length == 0 || process.stdout.ready)) {
   268             c = process.stdout.read
   269             if (c >= 0) result.append(c.asInstanceOf[Char])
   270             else done = true
   271           }
   272           if (result.length > 0) {
   273             put_result(Markup.STDOUT, result.toString)
   274             result.length = 0
   275           }
   276           else {
   277             process.stdout.close
   278             finished = true
   279           }
   280           //}}}
   281         }
   282         catch { case e: IOException => system_result(name + ": " + e.getMessage) }
   283       }
   284       system_result(name + " terminated")
   285     }
   286   }
   287 
   288 
   289   /* command input */
   290 
   291   private def input_actor(raw_stream: OutputStream): (Thread, Actor) =
   292   {
   293     val name = "command_input"
   294     Simple_Thread.actor(name) {
   295       val stream = new BufferedOutputStream(raw_stream)
   296       var finished = false
   297       while (!finished) {
   298         try {
   299           //{{{
   300           receive {
   301             case Input_Chunks(chunks) =>
   302               stream.write(Standard_System.string_bytes(
   303                   chunks.map(_.length).mkString("", ",", "\n")));
   304               chunks.foreach(stream.write(_));
   305               stream.flush
   306             case Close =>
   307               stream.close
   308               finished = true
   309             case bad => System.err.println(name + ": ignoring bad message " + bad)
   310           }
   311           //}}}
   312         }
   313         catch { case e: IOException => system_result(name + ": " + e.getMessage) }
   314       }
   315       system_result(name + " terminated")
   316     }
   317   }
   318 
   319 
   320   /* message output */
   321 
   322   private def message_actor(stream: InputStream): (Thread, Actor) =
   323   {
   324     class EOF extends Exception
   325     class Protocol_Error(msg: String) extends Exception(msg)
   326 
   327     val name = "message_output"
   328     Simple_Thread.actor(name) {
   329       val default_buffer = new Array[Byte](65536)
   330       var c = -1
   331 
   332       def read_chunk(decode: Boolean): XML.Body =
   333       {
   334         //{{{
   335         // chunk size
   336         var n = 0
   337         c = stream.read
   338         if (c == -1) throw new EOF
   339         while (48 <= c && c <= 57) {
   340           n = 10 * n + (c - 48)
   341           c = stream.read
   342         }
   343         if (c != 10) throw new Protocol_Error("bad message chunk header")
   344 
   345         // chunk content
   346         val buf =
   347           if (n <= default_buffer.size) default_buffer
   348           else new Array[Byte](n)
   349 
   350         var i = 0
   351         var m = 0
   352         do {
   353           m = stream.read(buf, i, n - i)
   354           if (m != -1) i += m
   355         } while (m != -1 && n > i)
   356 
   357         if (i != n) throw new Protocol_Error("bad message chunk content")
   358 
   359         if (decode)
   360           YXML.parse_body_failsafe(Standard_System.decode_chars(Symbol.decode, buf, 0, n))
   361         else List(XML.Text(Standard_System.decode_chars(s => s, buf, 0, n).toString))
   362         //}}}
   363       }
   364 
   365       do {
   366         try {
   367           val header = read_chunk(true)
   368           header match {
   369             case List(XML.Elem(Markup(name, props), Nil))
   370                 if name.size == 1 && Kind.message_markup.isDefinedAt(name(0)) =>
   371               val kind = Kind.message_markup(name(0))
   372               val body = read_chunk(kind != Markup.RAW)
   373               put_result(kind, props, body)
   374             case _ =>
   375               read_chunk(false)
   376               throw new Protocol_Error("bad header: " + header.toString)
   377           }
   378         }
   379         catch {
   380           case e: IOException => system_result("Cannot read message:\n" + e.getMessage)
   381           case e: Protocol_Error => system_result("Malformed message:\n" + e.getMessage)
   382           case _: EOF =>
   383         }
   384       } while (c != -1)
   385       stream.close
   386 
   387       system_result(name + " terminated")
   388     }
   389   }
   390 
   391 
   392   /** main methods **/
   393 
   394   def input_raw(text: String): Unit = standard_input._2 ! Input_Text(text)
   395 
   396   def input_bytes(name: String, args: Array[Byte]*): Unit =
   397     command_input._2 ! Input_Chunks(Standard_System.string_bytes(name) :: args.toList)
   398 
   399   def input(name: String, args: String*): Unit =
   400   {
   401     receiver(new Input(name, args.toList))
   402     input_bytes(name, args.map(Standard_System.string_bytes): _*)
   403   }
   404 
   405   def close(): Unit = { close(command_input); close(standard_input) }
   406 }