/* Title: Pure/System/isabelle_process.scala
Author: Makarius
Options: :folding=explicit:collapseFolds=1:
Isabelle process management -- always reactive due to multi-threaded I/O.
*/
package isabelle
import java.lang.System
import java.util.concurrent.LinkedBlockingQueue
import java.io.{BufferedReader, BufferedWriter, InputStreamReader, OutputStreamWriter,
InputStream, OutputStream, BufferedOutputStream, IOException}
import scala.actors.Actor
import Actor._
object Isabelle_Process
{
/* messages */
sealed abstract class Message
class Input(name: String, args: List[String]) extends Message
{
override def toString: String =
XML.Elem(Markup(Markup.PROVER_COMMAND, List((Markup.NAME, name))),
args.map(s =>
List(XML.Text("\n"), XML.elem(Markup.PROVER_ARG, YXML.parse_body(s)))).flatten).toString
}
class Output(val message: XML.Elem) extends Message
{
def kind: String = message.markup.name
def properties: Properties.T = message.markup.properties
def body: XML.Body = message.body
def is_init = kind == Markup.INIT
def is_exit = kind == Markup.EXIT
def is_stdout = kind == Markup.STDOUT
def is_stderr = kind == Markup.STDERR
def is_system = kind == Markup.SYSTEM
def is_status = kind == Markup.STATUS
def is_report = kind == Markup.REPORT
def is_protocol = kind == Markup.PROTOCOL
def is_syslog = is_init || is_exit || is_system || is_stderr
override def toString: String =
{
val res =
if (is_status || is_report) message.body.map(_.toString).mkString
else if (is_protocol) "..."
else Pretty.string_of(message.body)
if (properties.isEmpty)
kind.toString + " [[" + res + "]]"
else
kind.toString + " " +
(for ((x, y) <- properties) yield x + "=" + y).mkString("{", ",", "}") + " [[" + res + "]]"
}
}
}
class Isabelle_Process(
receiver: Isabelle_Process.Message => Unit = Console.println(_),
arguments: List[String] = Nil)
{
import Isabelle_Process._
/* text representation */
def encode(s: String): String = Symbol.encode(s)
def decode(s: String): String = Symbol.decode(s)
object Encode
{
val string: XML.Encode.T[String] = (s => XML.Encode.string(encode(s)))
}
/* output */
val xml_cache = new XML.Cache()
private def system_output(text: String)
{
receiver(new Output(XML.Elem(Markup(Markup.SYSTEM, Nil), List(XML.Text(text)))))
}
private def output_message(kind: String, props: Properties.T, body: XML.Body)
{
if (kind == Markup.INIT) system_channel.accepted()
if (kind == Markup.PROTOCOL)
receiver(new Output(XML.Elem(Markup(kind, props), body)))
else {
val main = XML.Elem(Markup(kind, props), Protocol.clean_message(body))
val reports = Protocol.message_reports(props, body)
for (msg <- main :: reports) receiver(new Output(xml_cache.elem(msg)))
}
}
private def exit_message(rc: Int)
{
output_message(Markup.EXIT, Markup.Return_Code(rc),
List(XML.Text("Return code: " + rc.toString)))
}
/* command input actor */
private case class Input_Chunks(chunks: List[Bytes])
private case object Close
private def close(p: (Thread, Actor))
{
if (p != null && p._1.isAlive) {
p._2 ! Close
p._1.join
}
}
@volatile private var command_input: (Thread, Actor) = null
/** process manager **/
def command_line(channel: System_Channel, args: List[String]): List[String] =
Isabelle_System.getenv_strict("ISABELLE_PROCESS") :: (channel.isabelle_args ::: args)
private val system_channel = System_Channel()
private val process =
try {
val cmdline = command_line(system_channel, arguments)
new Isabelle_System.Managed_Process(null, null, false, cmdline: _*)
}
catch { case e: IOException => system_channel.accepted(); throw(e) }
val (_, process_result) =
Simple_Thread.future("process_result") { process.join }
private def terminate_process()
{
try { process.terminate }
catch { case e: IOException => system_output("Failed to terminate Isabelle: " + e.getMessage) }
}
private val process_manager = Simple_Thread.fork("process_manager")
{
val (startup_failed, startup_errors) =
{
var finished: Option[Boolean] = None
val result = new StringBuilder(100)
while (finished.isEmpty && (process.stderr.ready || !process_result.is_finished)) {
while (finished.isEmpty && process.stderr.ready) {
try {
val c = process.stderr.read
if (c == 2) finished = Some(true)
else result += c.toChar
}
catch { case _: IOException => finished = Some(false) }
}
Thread.sleep(10)
}
(finished.isEmpty || !finished.get, result.toString.trim)
}
if (startup_errors != "") system_output(startup_errors)
process.stdin.close
if (startup_failed) {
exit_message(127)
Thread.sleep(300)
terminate_process()
process_result.join
}
else {
val (command_stream, message_stream) = system_channel.rendezvous()
val stdout = physical_output_actor(false)
val stderr = physical_output_actor(true)
command_input = input_actor(command_stream)
val message = message_actor(message_stream)
val rc = process_result.join
system_output("process terminated")
close(command_input)
for ((thread, _) <- List(stdout, stderr, command_input, message))
thread.join
system_output("process_manager terminated")
exit_message(rc)
}
system_channel.accepted()
}
/* management methods */
def join() { process_manager.join() }
def terminate()
{
close(command_input)
system_output("Terminating Isabelle process")
terminate_process()
}
/** stream actors **/
/* physical output */
private def physical_output_actor(err: Boolean): (Thread, Actor) =
{
val (name, reader, markup) =
if (err) ("standard_error", process.stderr, Markup.STDERR)
else ("standard_output", process.stdout, Markup.STDOUT)
Simple_Thread.actor(name) {
try {
var result = new StringBuilder(100)
var finished = false
while (!finished) {
//{{{
var c = -1
var done = false
while (!done && (result.length == 0 || reader.ready)) {
c = reader.read
if (c >= 0) result.append(c.asInstanceOf[Char])
else done = true
}
if (result.length > 0) {
output_message(markup, Nil, List(XML.Text(decode(result.toString))))
result.length = 0
}
else {
reader.close
finished = true
}
//}}}
}
}
catch { case e: IOException => system_output(name + ": " + e.getMessage) }
system_output(name + " terminated")
}
}
/* command input */
private def input_actor(raw_stream: OutputStream): (Thread, Actor) =
{
val name = "command_input"
Simple_Thread.actor(name) {
try {
val stream = new BufferedOutputStream(raw_stream)
var finished = false
while (!finished) {
//{{{
receive {
case Input_Chunks(chunks) =>
Bytes(chunks.map(_.length).mkString("", ",", "\n")).write(stream)
chunks.foreach(_.write(stream))
stream.flush
case Close =>
stream.close
finished = true
case bad => System.err.println(name + ": ignoring bad message " + bad)
}
//}}}
}
}
catch { case e: IOException => system_output(name + ": " + e.getMessage) }
system_output(name + " terminated")
}
}
/* message output */
private def message_actor(stream: InputStream): (Thread, Actor) =
{
class EOF extends Exception
class Protocol_Error(msg: String) extends Exception(msg)
val name = "message_output"
Simple_Thread.actor(name) {
val default_buffer = new Array[Byte](65536)
var c = -1
def read_int(): Int =
//{{{
{
var n = 0
c = stream.read
if (c == -1) throw new EOF
while (48 <= c && c <= 57) {
n = 10 * n + (c - 48)
c = stream.read
}
if (c != 10)
throw new Protocol_Error("malformed header: expected integer followed by newline")
else n
}
//}}}
def read_chunk(do_decode: Boolean): XML.Body =
//{{{
{
val n = read_int()
val buf =
if (n <= default_buffer.size) default_buffer
else new Array[Byte](n)
var i = 0
var m = 0
do {
m = stream.read(buf, i, n - i)
if (m != -1) i += m
}
while (m != -1 && n > i)
if (i != n)
throw new Protocol_Error("bad chunk (unexpected EOF after " + i + " of " + n + " bytes)")
if (do_decode)
YXML.parse_body_failsafe(UTF8.decode_chars(decode, buf, 0, n))
else List(XML.Text(UTF8.decode_chars(s => s, buf, 0, n).toString))
}
//}}}
try {
do {
try {
val header = read_chunk(true)
header match {
case List(XML.Elem(Markup(name, props), Nil)) =>
val kind = name.intern
val body = read_chunk(kind != Markup.PROTOCOL)
output_message(kind, props, body)
case _ =>
read_chunk(false)
throw new Protocol_Error("bad header: " + header.toString)
}
}
catch { case _: EOF => }
}
while (c != -1)
}
catch {
case e: IOException => system_output("Cannot read message:\n" + e.getMessage)
case e: Protocol_Error => system_output("Malformed message:\n" + e.getMessage)
}
stream.close
system_output(name + " terminated")
}
}
/** main methods **/
def protocol_command_raw(name: String, args: Bytes*): Unit =
command_input._2 ! Input_Chunks(Bytes(name) :: args.toList)
def protocol_command(name: String, args: String*)
{
receiver(new Input(name, args.toList))
protocol_command_raw(name, args.map(Bytes(_)): _*)
}
def options(opts: Options): Unit =
protocol_command("Isabelle_Process.options", YXML.string_of_body(opts.encode))
}