src/Pure/Tools/build_process.scala

clarified signature: prefer stateful object-oriented style, to make it fit better into physical world;

/*  Title:      Pure/Tools/build_process.scala
    Author:     Makarius

Build process for sessions, with build database, optional heap, and
optional presentation.
*/

package isabelle


import scala.math.Ordering
import scala.collection.immutable.SortedSet
import scala.annotation.tailrec


object Build_Process {
  /* static information */

  object Session_Context {
    def empty(session: String, timeout: Time): Session_Context =
      new Session_Context(session, timeout, Time.zero, Nil)

    def apply(
      session: String,
      timeout: Time,
      store: Sessions.Store,
      progress: Progress = new Progress
    ): Session_Context = {
      store.try_open_database(session) match {
        case None => empty(session, timeout)
        case Some(db) =>
          def ignore_error(msg: String) = {
            progress.echo_warning("Ignoring bad database " + db +
              " for session " + quote(session) + (if (msg == "") "" else ":\n" + msg))
            empty(session, timeout)
          }
          try {
            val command_timings = store.read_command_timings(db, session)
            val elapsed =
              store.read_session_timing(db, session) match {
                case Markup.Elapsed(s) => Time.seconds(s)
                case _ => Time.zero
              }
            new Session_Context(session, timeout, elapsed, command_timings)
          }
          catch {
            case ERROR(msg) => ignore_error(msg)
            case exn: java.lang.Error => ignore_error(Exn.message(exn))
            case _: XML.Error => ignore_error("XML.Error")
          }
          finally { db.close() }
      }
    }
  }

  final class Session_Context(
    val session: String,
    val timeout: Time,
    val old_time: Time,
    val old_command_timings: List[Properties.T]
  ) {
    def is_empty: Boolean = old_time.is_zero && old_command_timings.isEmpty

    override def toString: String = session
  }

  object Context {
    def apply(
      store: Sessions.Store,
      deps: Sessions.Deps,
      progress: Progress = new Progress
    ): Context = {
      val sessions_structure = deps.sessions_structure
      val build_graph = sessions_structure.build_graph

      val sessions =
        Map.from(
          for (name <- build_graph.keys_iterator)
          yield {
            val timeout = sessions_structure(name).timeout
            name -> Build_Process.Session_Context(name, timeout, store, progress = progress)
          })

      val sessions_time = {
        val maximals = build_graph.maximals.toSet
        def descendants_time(name: String): Double = {
          if (maximals.contains(name)) sessions(name).old_time.seconds
          else {
            val descendants = build_graph.all_succs(List(name)).toSet
            val g = build_graph.restrict(descendants)
            (0.0 :: g.maximals.flatMap { desc =>
              val ps = g.all_preds(List(desc))
              if (ps.exists(p => !sessions.isDefinedAt(p))) None
              else Some(ps.map(p => sessions(p).old_time.seconds).sum)
            }).max
          }
        }
        Map.from(
          for (name <- sessions.keysIterator)
          yield name -> descendants_time(name)).withDefaultValue(0.0)
      }

      val ordering =
        new Ordering[String] {
          def compare(name1: String, name2: String): Int =
            sessions_time(name2) compare sessions_time(name1) match {
              case 0 =>
                sessions(name2).timeout compare sessions(name1).timeout match {
                  case 0 => name1 compare name2
                  case ord => ord
                }
              case ord => ord
            }
        }

      new Context(store, deps, sessions, ordering, progress)
    }
  }

  final class Context private(
    val store: Sessions.Store,
    val deps: Sessions.Deps,
    sessions: Map[String, Session_Context],
    val ordering: Ordering[String],
    val progress: Progress
  ) {
    def sessions_structure: Sessions.Structure = deps.sessions_structure

    def apply(session: String): Session_Context =
      sessions.getOrElse(session, Session_Context.empty(session, Time.zero))

    def build_heap(session: String): Boolean =
      Sessions.is_pure(session) || !sessions_structure.build_graph.is_maximal(session)
  }


  /* main */

  case class Result(
    current: Boolean,
    output_heap: SHA1.Shasum,
    process_result: Process_Result
  ) {
    def ok: Boolean = process_result.ok
  }
}

class Build_Process(
  build_context: Build_Process.Context,
  build_heap: Boolean = false,
  numa_shuffling: Boolean = false,
  max_jobs: Int = 1,
  fresh_build: Boolean = false,
  no_build: Boolean = false,
  verbose: Boolean = false,
  session_setup: (String, Session) => Unit = (_, _) => ()
) {
  private val store = build_context.store
  private val build_options = store.options
  private val build_deps = build_context.deps
  private val progress = build_context.progress

  // global state
  private val numa_nodes = new NUMA.Nodes(numa_shuffling)
  private var build_graph = build_context.sessions_structure.build_graph
  private var build_order = SortedSet.from(build_graph.keys)(build_context.ordering)
  private var running = Map.empty[String, (SHA1.Shasum, Build_Job)]
  private var results = Map.empty[String, Build_Process.Result]

  private def sleep(): Unit =
    Isabelle_Thread.interrupt_handler(_ => progress.stop()) {
      build_options.seconds("editor_input_delay").sleep()
    }

  private val log =
    build_options.string("system_log") match {
      case "" => No_Logger
      case "-" => Logger.make(progress)
      case log_file => Logger.make(Some(Path.explode(log_file)))
    }

  private def remove_pending(name: String): Unit = {
    build_graph = build_graph.del_node(name)
    build_order = build_order - name
  }

  private def next_pending(): Option[String] =
    build_order.iterator
      .dropWhile(name => running.isDefinedAt(name) || !build_graph.is_minimal(name))
      .nextOption()

  private def used_node(i: Int): Boolean =
    running.iterator.exists(
      { case (_, (_, job)) => job.numa_node.isDefined && job.numa_node.get == i })

  private def session_finished(session_name: String, process_result: Process_Result): String =
    "Finished " + session_name + " (" + process_result.timing.message_resources + ")"

  private def session_timing(session_name: String, build_log: Build_Log.Session_Info): String = {
    val props = build_log.session_timing
    val threads = Markup.Session_Timing.Threads.unapply(props) getOrElse 1
    val timing = Markup.Timing_Properties.get(props)
    "Timing " + session_name + " (" + threads + " threads, " + timing.message_factor + ")"
  }

  def run(): Map[String, Build_Process.Result] = {
    @tailrec def loop(): Unit = {
      if (!build_graph.is_empty) {
        if (progress.stopped) {
          for ((_, (_, job)) <- running) job.terminate()
        }

        running.find({ case (_, (_, job)) => job.is_finished }) match {
          case Some((session_name, (input_heaps, job))) =>
            //{{{ finish job

            val process_result = job.join

            val output_heap =
              if (process_result.ok && job.do_store && store.output_heap(session_name).is_file) {
                SHA1.shasum(ML_Heap.write_digest(store.output_heap(session_name)), session_name)
              }
              else SHA1.no_shasum

            val log_lines = process_result.out_lines.filterNot(Protocol_Message.Marker.test)
            val process_result_tail = {
              val tail = job.info.options.int("process_output_tail")
              process_result.copy(
                out_lines =
                  "(more details via \"isabelle log -H Error " + session_name + "\")" ::
                  (if (tail == 0) log_lines else log_lines.drop(log_lines.length - tail max 0)))
            }

            val build_log =
              Build_Log.Log_File(session_name, process_result.out_lines).
                parse_session_info(
                  command_timings = true,
                  theory_timings = true,
                  ml_statistics = true,
                  task_statistics = true)

            // write log file
            if (process_result.ok) {
              File.write_gzip(store.output_log_gz(session_name), terminate_lines(log_lines))
            }
            else File.write(store.output_log(session_name), terminate_lines(log_lines))

            // write database
            using(store.open_database(session_name, output = true))(db =>
              store.write_session_info(db, session_name, job.session_sources,
                build_log =
                  if (process_result.timeout) build_log.error("Timeout") else build_log,
                build =
                  Build.Session_Info(build_deps.sources_shasum(session_name), input_heaps,
                    output_heap, process_result.rc, UUID.random().toString)))

            // messages
            process_result.err_lines.foreach(progress.echo)

            if (process_result.ok) {
              if (verbose) progress.echo(session_timing(session_name, build_log))
              progress.echo(session_finished(session_name, process_result))
            }
            else {
              progress.echo(session_name + " FAILED")
              if (!process_result.interrupted) progress.echo(process_result_tail.out)
            }

            remove_pending(session_name)
            running -= session_name
            results += (session_name -> Build_Process.Result(false, output_heap, process_result_tail))
            loop()
            //}}}
          case None if running.size < (max_jobs max 1) =>
            //{{{ check/start next job
            next_pending() match {
              case Some(session_name) =>
                val ancestor_results =
                  build_deps.sessions_structure.build_requirements(List(session_name)).
                    filterNot(_ == session_name).map(results(_))
                val input_heaps =
                  if (ancestor_results.isEmpty) {
                    SHA1.shasum_meta_info(SHA1.digest(Path.explode("$POLYML_EXE")))
                  }
                  else SHA1.flat_shasum(ancestor_results.map(_.output_heap))

                val do_store = build_heap || build_context.build_heap(session_name)
                val (current, output_heap) = {
                  store.try_open_database(session_name) match {
                    case Some(db) =>
                      using(db)(store.read_build(_, session_name)) match {
                        case Some(build) =>
                          val output_heap = store.find_heap_shasum(session_name)
                          val current =
                            !fresh_build &&
                            build.ok &&
                            build.sources == build_deps.sources_shasum(session_name) &&
                            build.input_heaps == input_heaps &&
                            build.output_heap == output_heap &&
                            !(do_store && output_heap.is_empty)
                          (current, output_heap)
                        case None => (false, SHA1.no_shasum)
                      }
                    case None => (false, SHA1.no_shasum)
                  }
                }
                val all_current = current && ancestor_results.forall(_.current)

                if (all_current) {
                  remove_pending(session_name)
                  results += (session_name -> Build_Process.Result(true, output_heap, Process_Result.ok))
                  loop()
                }
                else if (no_build) {
                  progress.echo_if(verbose, "Skipping " + session_name + " ...")
                  remove_pending(session_name)
                  results += (session_name -> Build_Process.Result(false, output_heap, Process_Result.error))
                  loop()
                }
                else if (ancestor_results.forall(_.ok) && !progress.stopped) {
                  progress.echo((if (do_store) "Building " else "Running ") + session_name + " ...")

                  store.clean_output(session_name)
                  using(store.open_database(session_name, output = true))(
                    store.init_session_info(_, session_name))

                  val session_background = build_deps.background(session_name)
                  val resources =
                    new Resources(session_background, log = log,
                      command_timings = build_context(session_name).old_command_timings)

                  val numa_node = numa_nodes.next(used_node)
                  val job =
                    new Build_Job(progress, session_background, store, do_store,
                      resources, session_setup, numa_node)
                  running += (session_name -> (input_heaps, job))
                  loop()
                }
                else {
                  progress.echo(session_name + " CANCELLED")
                  remove_pending(session_name)
                  results += (session_name -> Build_Process.Result(false, output_heap, Process_Result.undefined))
                  loop()
                }
              case None => sleep(); loop()
            }
            ///}}}
          case None => sleep(); loop()
        }
      }
    }

    loop()
    results
  }
}