/* Title: Pure/System/session.scala
Author: Makarius
Options: :folding=explicit:collapseFolds=1:
Main Isabelle/Scala session, potentially with running prover process.
*/
package isabelle
import java.lang.System
import java.util.{Timer, TimerTask}
import scala.collection.mutable
import scala.actors.TIMEOUT
import scala.actors.Actor._
object Session
{
/* events */
//{{{
case object Global_Settings
case object Caret_Focus
case class Commands_Changed(nodes: Set[Document.Node.Name], commands: Set[Command])
sealed abstract class Phase
case object Inactive extends Phase
case object Startup extends Phase // transient
case object Failed extends Phase
case object Ready extends Phase
case object Shutdown extends Phase // transient
//}}}
}
class Session(thy_load: Thy_Load = new Thy_Load)
{
/* real time parameters */ // FIXME properties or settings (!?)
val message_delay = Time.seconds(0.01) // prover messages
val input_delay = Time.seconds(0.3) // user input (e.g. text edits, cursor movement)
val output_delay = Time.seconds(0.1) // prover output (markup, common messages)
val update_delay = Time.seconds(0.5) // GUI layout updates
val load_delay = Time.seconds(0.5) // file load operations (new buffers etc.)
val prune_delay = Time.seconds(60.0) // prune history -- delete old versions
val prune_size = 0 // size of retained history
/* pervasive event buses */
val global_settings = new Event_Bus[Session.Global_Settings.type]
val caret_focus = new Event_Bus[Session.Caret_Focus.type]
val commands_changed = new Event_Bus[Session.Commands_Changed]
val phase_changed = new Event_Bus[Session.Phase]
val syslog_messages = new Event_Bus[Isabelle_Process.Result]
val raw_output_messages = new Event_Bus[Isabelle_Process.Result]
val protocol_messages = new Event_Bus[Isabelle_Process.Message] // potential bottle-neck
/** buffered command changes (delay_first discipline) **/
//{{{
private case object Stop
private val (_, commands_changed_buffer) =
Simple_Thread.actor("commands_changed_buffer", daemon = true)
{
var finished = false
while (!finished) {
receive {
case Stop => finished = true; reply(())
case changed: Session.Commands_Changed => commands_changed.event(changed)
case bad => System.err.println("commands_changed_buffer: ignoring bad message " + bad)
}
}
}
//}}}
/** pipelined change parsing **/
//{{{
private case class Text_Edits(
syntax: Outer_Syntax,
name: Document.Node.Name,
previous: Future[Document.Version],
text_edits: List[Document.Edit_Text],
version_result: Promise[Document.Version])
private val (_, change_parser) = Simple_Thread.actor("change_parser", daemon = true)
{
var finished = false
while (!finished) {
receive {
case Stop => finished = true; reply(())
case Text_Edits(syntax, name, previous, text_edits, version_result) =>
val prev = previous.get_finished
val (doc_edits, version) = Thy_Syntax.text_edits(syntax, prev, text_edits)
version_result.fulfill(version)
sender ! Change_Node(name, doc_edits, prev, version)
case bad => System.err.println("change_parser: ignoring bad message " + bad)
}
}
}
//}}}
/** main protocol actor **/
/* global state */
@volatile var verbose: Boolean = false
@volatile private var syntax = Outer_Syntax.init()
def current_syntax(): Outer_Syntax = syntax
@volatile private var reverse_syslog = List[XML.Elem]()
def syslog(): String = cat_lines(reverse_syslog.reverse.map(msg => XML.content(msg).mkString))
@volatile private var _phase: Session.Phase = Session.Inactive
private def phase_=(new_phase: Session.Phase)
{
_phase = new_phase
phase_changed.event(new_phase)
}
def phase = _phase
def is_ready: Boolean = phase == Session.Ready
private val global_state = Volatile(Document.State.init)
def current_state(): Document.State = global_state()
def snapshot(name: Document.Node.Name = Document.Node.Name.empty,
pending_edits: List[Text.Edit] = Nil): Document.Snapshot =
global_state().snapshot(name, pending_edits)
/* theory files */
def header_edit(name: Document.Node.Name, header: Document.Node_Header): Document.Edit_Text =
{
def norm_import(s: String): String =
{
val thy_name = Thy_Header.base_name(s)
if (thy_load.is_loaded(thy_name)) thy_name
else thy_load.append(name.dir, Thy_Header.thy_path(Path.explode(s)))
}
def norm_use(s: String): String = thy_load.append(name.dir, Path.explode(s))
val header1: Document.Node_Header =
header match {
case Exn.Res(Thy_Header(thy_name, _, _))
if (thy_load.is_loaded(thy_name)) =>
Exn.Exn(ERROR("Attempt to update loaded theory " + quote(thy_name)))
case _ => Document.Node.norm_header(norm_import, norm_use, header)
}
(name, Document.Node.Header(header1))
}
/* actor messages */
private case class Start(timeout: Time, args: List[String])
private case object Cancel_Execution
private case class Init_Node(name: Document.Node.Name,
header: Document.Node_Header, perspective: Text.Perspective, text: String)
private case class Edit_Node(name: Document.Node.Name,
header: Document.Node_Header, perspective: Text.Perspective, edits: List[Text.Edit])
private case class Change_Node(
name: Document.Node.Name,
doc_edits: List[Document.Edit_Command],
previous: Document.Version,
version: Document.Version)
private case class Messages(msgs: List[Isabelle_Process.Message])
private val (_, session_actor) = Simple_Thread.actor("session_actor", daemon = true)
{
val this_actor = self
var prune_next = System.currentTimeMillis() + prune_delay.ms
/* buffered prover messages */
object receiver
{
private var buffer = new mutable.ListBuffer[Isabelle_Process.Message]
def flush(): Unit = synchronized {
if (!buffer.isEmpty) {
val msgs = buffer.toList
this_actor ! Messages(msgs)
buffer = new mutable.ListBuffer[Isabelle_Process.Message]
}
}
def invoke(msg: Isabelle_Process.Message): Unit = synchronized {
buffer += msg
msg match {
case result: Isabelle_Process.Result if result.is_raw => flush()
case _ =>
}
}
private val timer = new Timer("session_actor.receiver", true)
timer.schedule(new TimerTask { def run = flush }, message_delay.ms, message_delay.ms)
def cancel() { timer.cancel() }
}
var prover: Option[Isabelle_Process with Protocol] = None
/* delayed command changes */
object delay_commands_changed
{
private var changed_nodes: Set[Document.Node.Name] = Set.empty
private var changed_commands: Set[Command] = Set.empty
private def changed: Boolean = !changed_nodes.isEmpty || !changed_commands.isEmpty
private var flush_time: Option[Long] = None
def flush_timeout: Long =
flush_time match {
case None => 5000L
case Some(time) => (time - System.currentTimeMillis()) max 0
}
def flush()
{
if (changed)
commands_changed_buffer ! Session.Commands_Changed(changed_nodes, changed_commands)
changed_nodes = Set.empty
changed_commands = Set.empty
flush_time = None
}
def invoke(command: Command)
{
changed_nodes += command.node_name
changed_commands += command
val now = System.currentTimeMillis()
flush_time match {
case None => flush_time = Some(now + output_delay.ms)
case Some(time) => if (now >= time) flush()
}
}
}
/* perspective */
def update_perspective(name: Document.Node.Name, text_perspective: Text.Perspective)
{
val previous = global_state().tip_version
val (perspective, version) = Thy_Syntax.edit_perspective(previous, name, text_perspective)
val text_edits: List[Document.Edit_Text] =
List((name, Document.Node.Perspective(text_perspective)))
val change =
global_state >>>
(_.continue_history(Future.value(previous), text_edits, Future.value(version)))
val assignment = global_state().the_assignment(previous).check_finished
global_state >> (_.define_version(version, assignment))
global_state >>> (_.assign(version.id))
prover.get.update_perspective(previous.id, version.id, name, perspective)
}
/* incoming edits */
def handle_edits(name: Document.Node.Name,
header: Document.Node_Header, edits: List[Document.Node.Edit[Text.Edit, Text.Perspective]])
//{{{
{
val syntax = current_syntax()
val previous = global_state().history.tip.version
prover.get.cancel_execution()
val text_edits = header_edit(name, header) :: edits.map(edit => (name, edit))
val version = Future.promise[Document.Version]
val change = global_state >>> (_.continue_history(previous, text_edits, version))
change_parser ! Text_Edits(syntax, name, previous, text_edits, version)
}
//}}}
/* exec state assignment */
def handle_assign(id: Document.Version_ID, assign: Document.Assign)
//{{{
{
val cmds = global_state >>> (_.assign(id, assign))
for (cmd <- cmds) delay_commands_changed.invoke(cmd)
}
//}}}
/* removed versions */
def handle_removed(removed: List[Document.Version_ID])
//{{{
{
global_state >> (_.removed_versions(removed))
}
//}}}
/* resulting changes */
def handle_change(change: Change_Node)
//{{{
{
val previous = change.previous
val version = change.version
val name = change.name
val doc_edits = change.doc_edits
def id_command(command: Command)
{
if (!global_state().defined_command(command.id)) {
global_state >> (_.define_command(command))
prover.get.define_command(command)
}
}
doc_edits foreach {
case (_, edit) =>
edit foreach { case (c1, c2) => c1 foreach id_command; c2 foreach id_command }
}
val assignment = global_state().the_assignment(previous).check_finished
global_state >> (_.define_version(version, assignment))
prover.get.update(previous.id, version.id, doc_edits)
}
//}}}
/* prover results */
def handle_result(result: Isabelle_Process.Result)
//{{{
{
def bad_result(result: Isabelle_Process.Result)
{
if (verbose)
System.err.println("Ignoring prover result: " + result.message.toString)
}
result.properties match {
case Position.Id(state_id) if !result.is_raw =>
try {
val st = global_state >>> (_.accumulate(state_id, result.message))
delay_commands_changed.invoke(st.command)
}
catch {
case _: Document.State.Fail => bad_result(result)
}
case Isabelle_Markup.Assign_Execs if result.is_raw =>
XML.content(result.body).mkString match {
case Protocol.Assign(id, assign) =>
try { handle_assign(id, assign) }
catch { case _: Document.State.Fail => bad_result(result) }
case _ => bad_result(result)
}
// FIXME separate timeout event/message!?
if (prover.isDefined && System.currentTimeMillis() > prune_next) {
val old_versions = global_state >>> (_.prune_history(prune_size))
if (!old_versions.isEmpty) prover.get.remove_versions(old_versions)
prune_next = System.currentTimeMillis() + prune_delay.ms
}
case Isabelle_Markup.Removed_Versions if result.is_raw =>
XML.content(result.body).mkString match {
case Protocol.Removed(removed) =>
try { handle_removed(removed) }
catch { case _: Document.State.Fail => bad_result(result) }
case _ => bad_result(result)
}
case Isabelle_Markup.Invoke_Scala(name, id) if result.is_raw =>
Future.fork {
val arg = XML.content(result.body).mkString
val (tag, res) = Invoke_Scala.method(name, arg)
prover.get.invoke_scala(id, tag, res)
}
case Isabelle_Markup.Cancel_Scala(id) if result.is_raw =>
System.err.println("cancel_scala " + id) // FIXME actually cancel JVM task
case Isabelle_Markup.Ready if result.is_raw =>
// FIXME move to ML side (!?)
syntax += ("hence", Keyword.PRF_ASM_GOAL, "then have")
syntax += ("thus", Keyword.PRF_ASM_GOAL, "then show")
phase = Session.Ready
case Isabelle_Markup.Loaded_Theory(name) if result.is_raw =>
thy_load.register_thy(name)
case Isabelle_Markup.Command_Decl(name, kind) if result.is_raw =>
syntax += (name, kind)
case Isabelle_Markup.Keyword_Decl(name) if result.is_raw =>
syntax += name
case _ =>
if (result.is_syslog) {
reverse_syslog ::= result.message
if (result.is_exit && phase == Session.Startup) phase = Session.Failed
else if (result.is_exit) phase = Session.Inactive
}
else if (result.is_stdout) { }
else bad_result(result)
}
}
//}}}
/* main loop */
//{{{
var finished = false
while (!finished) {
receiveWithin(delay_commands_changed.flush_timeout) {
case TIMEOUT => delay_commands_changed.flush()
case Start(timeout, args) if prover.isEmpty =>
if (phase == Session.Inactive || phase == Session.Failed) {
phase = Session.Startup
prover = Some(new Isabelle_Process(timeout, receiver.invoke _, args) with Protocol)
}
case Stop =>
if (phase == Session.Ready) {
global_state >> (_ => Document.State.init) // FIXME event bus!?
phase = Session.Shutdown
prover.get.terminate
prover = None
phase = Session.Inactive
}
finished = true
receiver.cancel()
reply(())
case Cancel_Execution if prover.isDefined =>
prover.get.cancel_execution()
case Init_Node(name, header, perspective, text) if prover.isDefined =>
// FIXME compare with existing node
handle_edits(name, header,
List(Document.Node.Clear(),
Document.Node.Edits(List(Text.Edit.insert(0, text))),
Document.Node.Perspective(perspective)))
reply(())
case Edit_Node(name, header, perspective, text_edits) if prover.isDefined =>
if (text_edits.isEmpty && global_state().tip_stable &&
perspective.range.stop <= global_state().last_exec_offset(name))
update_perspective(name, perspective)
else
handle_edits(name, header,
List(Document.Node.Edits(text_edits), Document.Node.Perspective(perspective)))
reply(())
case Messages(msgs) =>
msgs foreach {
case input: Isabelle_Process.Input =>
protocol_messages.event(input)
case result: Isabelle_Process.Result =>
handle_result(result)
if (result.is_syslog) syslog_messages.event(result)
if (result.is_stdout || result.is_stderr) raw_output_messages.event(result)
protocol_messages.event(result)
}
case change: Change_Node
if prover.isDefined && global_state().is_assigned(change.previous) =>
handle_change(change)
case bad if !bad.isInstanceOf[Change_Node] =>
System.err.println("session_actor: ignoring bad message " + bad)
}
}
//}}}
}
/* actions */
def start(timeout: Time, args: List[String])
{ session_actor ! Start(timeout, args) }
def start(args: List[String]) { start (Time.seconds(25), args) }
def stop() { commands_changed_buffer !? Stop; change_parser !? Stop; session_actor !? Stop }
def cancel_execution() { session_actor ! Cancel_Execution }
def init_node(name: Document.Node.Name,
header: Document.Node_Header, perspective: Text.Perspective, text: String)
{ session_actor !? Init_Node(name, header, perspective, text) }
def edit_node(name: Document.Node.Name,
header: Document.Node_Header, perspective: Text.Perspective, edits: List[Text.Edit])
{ session_actor !? Edit_Node(name, header, perspective, edits) }
}