/* Title: Pure/System/isabelle_process.ML
Author: Makarius
Options: :folding=explicit:collapseFolds=1:
Isabelle process management -- always reactive due to multi-threaded I/O.
*/
package isabelle
import java.util.concurrent.LinkedBlockingQueue
import java.io.{BufferedReader, BufferedWriter, InputStreamReader, OutputStreamWriter,
InputStream, OutputStream, IOException}
import scala.actors.Actor
import Actor._
object Isabelle_Process
{
/* results */
object Kind {
// message markup
val markup = Map(
('A' : Int) -> Markup.INIT,
('B' : Int) -> Markup.STATUS,
('C' : Int) -> Markup.WRITELN,
('D' : Int) -> Markup.TRACING,
('E' : Int) -> Markup.WARNING,
('F' : Int) -> Markup.ERROR,
('G' : Int) -> Markup.DEBUG)
def is_raw(kind: String) =
kind == Markup.STDOUT
def is_control(kind: String) =
kind == Markup.SYSTEM ||
kind == Markup.SIGNAL ||
kind == Markup.EXIT
def is_system(kind: String) =
kind == Markup.SYSTEM ||
kind == Markup.STDIN ||
kind == Markup.SIGNAL ||
kind == Markup.EXIT ||
kind == Markup.STATUS
}
class Result(val message: XML.Elem)
{
def kind = message.markup.name
def properties = message.markup.properties
def body = message.body
def is_raw = Kind.is_raw(kind)
def is_control = Kind.is_control(kind)
def is_system = Kind.is_system(kind)
def is_status = kind == Markup.STATUS
def is_ready = is_status && body == List(XML.Elem(Markup.Ready, Nil))
override def toString: String =
{
val res =
if (is_status) message.body.map(_.toString).mkString
else Pretty.string_of(message.body)
if (properties.isEmpty)
kind.toString + " [[" + res + "]]"
else
kind.toString + " " +
(for ((x, y) <- properties) yield x + "=" + y).mkString("{", ",", "}") + " [[" + res + "]]"
}
def cache(c: XML.Cache): Result = new Result(c.cache_tree(message).asInstanceOf[XML.Elem])
}
}
class Isabelle_Process(system: Isabelle_System, receiver: Actor, args: String*)
{
import Isabelle_Process._
/* demo constructor */
def this(args: String*) =
this(new Isabelle_System,
actor { loop { react { case res => Console.println(res) } } }, args: _*)
/* process information */
@volatile private var proc: Process = null
@volatile private var closing = false
@volatile private var pid: String = null
/* results */
private def put_result(kind: String, props: List[(String, String)], body: List[XML.Tree])
{
if (kind == Markup.INIT) {
for ((Markup.PID, p) <- props) pid = p
}
receiver ! new Result(XML.Elem(Markup(kind, props), body))
}
private def put_result(kind: String, text: String)
{
put_result(kind, Nil, List(XML.Text(system.symbols.decode(text))))
}
/* signals */
def interrupt() = synchronized {
if (proc == null) error("Cannot interrupt Isabelle: no process")
if (pid == null) put_result(Markup.SYSTEM, "Cannot interrupt: unknown pid")
else {
try {
if (system.execute(true, "kill", "-INT", pid).waitFor == 0)
put_result(Markup.SIGNAL, "INT")
else
put_result(Markup.SYSTEM, "Cannot interrupt: kill command failed")
}
catch { case e: IOException => error("Cannot interrupt Isabelle: " + e.getMessage) }
}
}
def kill() = synchronized {
if (proc == 0) error("Cannot kill Isabelle: no process")
else {
try_close()
Thread.sleep(500) // FIXME property!?
put_result(Markup.SIGNAL, "KILL")
proc.destroy
proc = null
pid = null
}
}
/* output being piped into the process */
private val output = new LinkedBlockingQueue[String]
private def output_raw(text: String) = synchronized {
if (proc == null) error("Cannot output to Isabelle: no process")
if (closing) error("Cannot output to Isabelle: already closing")
output.put(text)
}
def output_sync(text: String) =
output_raw(" \\<^sync>\n; " + text + " \\<^sync>;\n")
def command(text: String) =
output_sync("Isabelle.command " + Isabelle_Syntax.encode_string(text))
def command(props: List[(String, String)], text: String) =
output_sync("Isabelle.command " + Isabelle_Syntax.encode_properties(props) + " " +
Isabelle_Syntax.encode_string(text))
def ML_val(text: String) =
output_sync("ML_val " + Isabelle_Syntax.encode_string(text))
def ML_command(text: String) =
output_sync("ML_command " + Isabelle_Syntax.encode_string(text))
def close() = synchronized { // FIXME watchdog/timeout
output_raw("\u0000")
closing = true
}
def try_close() = synchronized {
if (proc != null && !closing) {
try { close() }
catch { case _: RuntimeException => }
}
}
/* stdin */
private class Stdin_Thread(out_stream: OutputStream) extends Thread("isabelle: stdin") {
override def run() = {
val writer = new BufferedWriter(new OutputStreamWriter(out_stream, Standard_System.charset))
var finished = false
while (!finished) {
try {
//{{{
val s = output.take
if (s == "\u0000") {
writer.close
finished = true
}
else {
put_result(Markup.STDIN, s)
writer.write(s)
writer.flush
}
//}}}
}
catch {
case e: IOException => put_result(Markup.SYSTEM, "Stdin thread: " + e.getMessage)
}
}
put_result(Markup.SYSTEM, "Stdin thread terminated")
}
}
/* stdout */
private class Stdout_Thread(in_stream: InputStream) extends Thread("isabelle: stdout") {
override def run() = {
val reader = new BufferedReader(new InputStreamReader(in_stream, Standard_System.charset))
var result = new StringBuilder(100)
var finished = false
while (!finished) {
try {
//{{{
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) {
put_result(Markup.STDOUT, result.toString)
result.length = 0
}
else {
reader.close
finished = true
try_close()
}
//}}}
}
catch {
case e: IOException => put_result(Markup.SYSTEM, "Stdout thread: " + e.getMessage)
}
}
put_result(Markup.SYSTEM, "Stdout thread terminated")
}
}
/* messages */
private class Message_Thread(fifo: String) extends Thread("isabelle: messages")
{
private class Protocol_Error(msg: String) extends Exception(msg)
override def run()
{
val stream = system.fifo_stream(fifo)
val default_buffer = new Array[Byte](65536)
var c = -1
def read_chunk(): List[XML.Tree] =
{
//{{{
// chunk size
var n = 0
c = stream.read
while (48 <= c && c <= 57) {
n = 10 * n + (c - 48)
c = stream.read
}
if (c != 10) throw new Protocol_Error("bad message chunk header")
// chunk content
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)
i += m
} while (m > 0 && n > i)
if (i != n) throw new Protocol_Error("bad message chunk content")
YXML.parse_body_failsafe(YXML.decode_chars(system.symbols.decode, buf, 0, n))
//}}}
}
do {
try {
//{{{
c = stream.read
var non_sync = 0
while (c >= 0 && c != 2) {
non_sync += 1
c = stream.read
}
if (non_sync > 0)
throw new Protocol_Error("lost synchronization -- skipping " + non_sync + " bytes")
if (c == 2) {
val header = read_chunk()
val body = read_chunk()
header match {
case List(XML.Elem(Markup(name, props), Nil))
if name.size == 1 && Kind.markup.isDefinedAt(name(0)) =>
put_result(Kind.markup(name(0)), props, body)
case _ => throw new Protocol_Error("bad header: " + header.toString)
}
}
//}}}
}
catch {
case e: IOException =>
put_result(Markup.SYSTEM, "Cannot read message:\n" + e.getMessage)
case e: Protocol_Error =>
put_result(Markup.SYSTEM, "Malformed message:\n" + e.getMessage)
}
} while (c != -1)
stream.close
try_close()
put_result(Markup.SYSTEM, "Message thread terminated")
}
}
/** main **/
{
/* messages */
val message_fifo = system.mk_fifo()
def rm_fifo() = system.rm_fifo(message_fifo)
val message_thread = new Message_Thread(message_fifo)
message_thread.start
/* exec process */
try {
val cmdline = List(system.getenv_strict("ISABELLE_PROCESS"), "-W", message_fifo) ++ args
proc = system.execute(true, cmdline: _*)
}
catch {
case e: IOException =>
rm_fifo()
error("Failed to execute Isabelle process: " + e.getMessage)
}
/* stdin/stdout */
new Stdin_Thread(proc.getOutputStream).start
new Stdout_Thread(proc.getInputStream).start
/* exit */
new Thread("isabelle: exit") {
override def run() = {
val rc = proc.waitFor()
Thread.sleep(300) // FIXME property!?
put_result(Markup.SYSTEM, "Exit thread terminated")
put_result(Markup.EXIT, rc.toString)
rm_fifo()
}
}.start
}
}