src/Pure/Thy/sessions.scala
author wenzelm
Thu Nov 02 11:25:37 2017 +0100 (18 months ago)
changeset 66988 7f8c1dd7576a
parent 66987 352b23c97ac8
child 66990 b23adab22e67
permissions -rw-r--r--
support alternative ancestor session;
     1 /*  Title:      Pure/Thy/sessions.scala
     2     Author:     Makarius
     3 
     4 Cumulative session information.
     5 */
     6 
     7 package isabelle
     8 
     9 import java.io.{File => JFile}
    10 import java.nio.ByteBuffer
    11 import java.nio.channels.FileChannel
    12 import java.nio.file.StandardOpenOption
    13 
    14 import scala.collection.SortedSet
    15 import scala.collection.mutable
    16 
    17 
    18 object Sessions
    19 {
    20   /* base info and source dependencies */
    21 
    22   val DRAFT = "Draft"
    23 
    24   def is_pure(name: String): Boolean = name == Thy_Header.PURE
    25 
    26   object Known
    27   {
    28     val empty: Known = Known()
    29 
    30     def make(local_dir: Path, bases: List[Base],
    31       theories: List[Document.Node.Name] = Nil,
    32       loaded_files: List[(String, List[Path])] = Nil): Known =
    33     {
    34       def bases_iterator(local: Boolean) =
    35         for {
    36           base <- bases.iterator
    37           (_, name) <- (if (local) base.known.theories_local else base.known.theories).iterator
    38         } yield name
    39 
    40       def local_theories_iterator =
    41       {
    42         val local_path = local_dir.canonical_file.toPath
    43         theories.iterator.filter(name => name.path.canonical_file.toPath.startsWith(local_path))
    44       }
    45 
    46       val known_theories =
    47         (Map.empty[String, Document.Node.Name] /: (bases_iterator(false) ++ theories.iterator))({
    48           case (known, name) =>
    49             known.get(name.theory) match {
    50               case Some(name1) if name != name1 =>
    51                 error("Duplicate theory " + quote(name.node) + " vs. " + quote(name1.node))
    52               case _ => known + (name.theory -> name)
    53             }
    54           })
    55       val known_theories_local =
    56         (Map.empty[String, Document.Node.Name] /:
    57             (bases_iterator(true) ++ local_theories_iterator))({
    58           case (known, name) => known + (name.theory -> name)
    59         })
    60       val known_files =
    61         (Map.empty[JFile, List[Document.Node.Name]] /:
    62             (bases_iterator(true) ++ bases_iterator(false) ++ theories.iterator))({
    63           case (known, name) =>
    64             val file = name.path.canonical_file
    65             val theories1 = known.getOrElse(file, Nil)
    66             if (theories1.exists(name1 => name.node == name1.node && name.theory == name1.theory))
    67               known
    68             else known + (file -> (name :: theories1))
    69         })
    70 
    71       val known_loaded_files =
    72         (loaded_files.toMap /: bases.map(base => base.known.loaded_files))(_ ++ _)
    73 
    74       Known(known_theories, known_theories_local,
    75         known_files.iterator.map(p => (p._1, p._2.reverse)).toMap,
    76         known_loaded_files)
    77     }
    78   }
    79 
    80   sealed case class Known(
    81     theories: Map[String, Document.Node.Name] = Map.empty,
    82     theories_local: Map[String, Document.Node.Name] = Map.empty,
    83     files: Map[JFile, List[Document.Node.Name]] = Map.empty,
    84     loaded_files: Map[String, List[Path]] = Map.empty)
    85   {
    86     def platform_path: Known =
    87       copy(theories = for ((a, b) <- theories) yield (a, b.map(File.platform_path(_))),
    88         theories_local = for ((a, b) <- theories_local) yield (a, b.map(File.platform_path(_))),
    89         files = for ((a, b) <- files) yield (a, b.map(c => c.map(File.platform_path(_)))))
    90 
    91     def standard_path: Known =
    92       copy(theories = for ((a, b) <- theories) yield (a, b.map(File.standard_path(_))),
    93         theories_local = for ((a, b) <- theories_local) yield (a, b.map(File.standard_path(_))),
    94         files = for ((a, b) <- files) yield (a, b.map(c => c.map(File.standard_path(_)))))
    95 
    96     def get_file(file: JFile, bootstrap: Boolean = false): Option[Document.Node.Name] =
    97     {
    98       val res = files.getOrElse(File.canonical(file), Nil).headOption
    99       if (bootstrap) res.map(_.map_theory(Thy_Header.bootstrap_name(_))) else res
   100     }
   101   }
   102 
   103   object Base
   104   {
   105     def bootstrap(global_theories: Map[String, String]): Base =
   106       Base(
   107         global_theories = global_theories,
   108         overall_syntax = Thy_Header.bootstrap_syntax)
   109   }
   110 
   111   sealed case class Base(
   112     pos: Position.T = Position.none,
   113     global_theories: Map[String, String] = Map.empty,
   114     loaded_theories: Graph[String, Outer_Syntax] = Graph.string,
   115     known: Known = Known.empty,
   116     overall_syntax: Outer_Syntax = Outer_Syntax.empty,
   117     imported_sources: List[(Path, SHA1.Digest)] = Nil,
   118     sources: List[(Path, SHA1.Digest)] = Nil,
   119     session_graph_display: Graph_Display.Graph = Graph_Display.empty_graph,
   120     errors: List[String] = Nil,
   121     imports: Option[Base] = None)
   122   {
   123     def platform_path: Base = copy(known = known.platform_path)
   124     def standard_path: Base = copy(known = known.standard_path)
   125 
   126     def theory_qualifier(name: String): String =
   127       global_theories.getOrElse(name, Long_Name.qualifier(name))
   128     def theory_qualifier(name: Document.Node.Name): String = theory_qualifier(name.theory)
   129 
   130     def loaded_theory(name: String): Boolean = loaded_theories.defined(name)
   131     def loaded_theory(name: Document.Node.Name): Boolean = loaded_theory(name.theory)
   132 
   133     def loaded_theory_syntax(name: String): Option[Outer_Syntax] =
   134       if (loaded_theory(name)) Some(loaded_theories.get_node(name)) else None
   135     def loaded_theory_syntax(name: Document.Node.Name): Option[Outer_Syntax] =
   136       loaded_theory_syntax(name.theory)
   137 
   138     def node_syntax(nodes: Document.Nodes, name: Document.Node.Name): Outer_Syntax =
   139       nodes(name).syntax orElse loaded_theory_syntax(name) getOrElse overall_syntax
   140 
   141     def known_theory(name: String): Option[Document.Node.Name] =
   142       known.theories.get(name)
   143 
   144     def dest_known_theories: List[(String, String)] =
   145       for ((theory, node_name) <- known.theories.toList)
   146         yield (theory, node_name.node)
   147 
   148     def get_imports: Base = imports getOrElse Base.bootstrap(global_theories)
   149   }
   150 
   151   sealed case class Deps(session_bases: Map[String, Base], all_known: Known)
   152   {
   153     def is_empty: Boolean = session_bases.isEmpty
   154     def apply(name: String): Base = session_bases(name)
   155     def get(name: String): Option[Base] = session_bases.get(name)
   156 
   157     def imported_sources(name: String): List[SHA1.Digest] =
   158       session_bases(name).imported_sources.map(_._2)
   159 
   160     def sources(name: String): List[SHA1.Digest] =
   161       session_bases(name).sources.map(_._2)
   162 
   163     def errors: List[String] =
   164       (for {
   165         (name, base) <- session_bases.iterator
   166         if base.errors.nonEmpty
   167       } yield cat_lines(base.errors) +
   168           "\nThe error(s) above occurred in session " + quote(name) + Position.here(base.pos)
   169       ).toList
   170 
   171     def check_errors: Deps =
   172       errors match {
   173         case Nil => this
   174         case errs => error(cat_lines(errs))
   175       }
   176   }
   177 
   178   def deps(sessions: T,
   179       global_theories: Map[String, String],
   180       progress: Progress = No_Progress,
   181       inlined_files: Boolean = false,
   182       verbose: Boolean = false,
   183       list_files: Boolean = false,
   184       check_keywords: Set[String] = Set.empty): Deps =
   185   {
   186     var cache_sources = Map.empty[JFile, SHA1.Digest]
   187     def check_sources(paths: List[Path]): List[(Path, SHA1.Digest)] =
   188     {
   189       for {
   190         path <- paths
   191         file = path.file
   192         if cache_sources.isDefinedAt(file) || file.isFile
   193       }
   194       yield {
   195         cache_sources.get(file) match {
   196           case Some(digest) => (path, digest)
   197           case None =>
   198             val digest = SHA1.digest(file)
   199             cache_sources = cache_sources + (file -> digest)
   200             (path, digest)
   201         }
   202       }
   203     }
   204 
   205     val session_bases =
   206       (Map.empty[String, Base] /: sessions.imports_topological_order)({
   207         case (session_bases, info) =>
   208           if (progress.stopped) throw Exn.Interrupt()
   209 
   210           try {
   211             val parent_base: Sessions.Base =
   212               info.parent match {
   213                 case None => Base.bootstrap(global_theories)
   214                 case Some(parent) => session_bases(parent)
   215               }
   216             val imports_base: Sessions.Base =
   217               parent_base.copy(known =
   218                 Known.make(info.dir, parent_base :: info.imports.map(session_bases(_))))
   219 
   220             val resources = new Resources(imports_base)
   221 
   222             if (verbose || list_files) {
   223               val groups =
   224                 if (info.groups.isEmpty) ""
   225                 else info.groups.mkString(" (", " ", ")")
   226               progress.echo("Session " + info.chapter + "/" + info.name + groups)
   227             }
   228 
   229             val thy_deps =
   230               resources.dependencies(
   231                 for { (_, thys) <- info.theories; (thy, pos) <- thys }
   232                 yield (resources.import_name(info.name, info.dir.implode, thy), pos))
   233 
   234             val overall_syntax = thy_deps.overall_syntax
   235 
   236             val theory_files = thy_deps.names.map(_.path)
   237             val loaded_files =
   238               if (inlined_files) {
   239                 if (Sessions.is_pure(info.name)) {
   240                   (Thy_Header.PURE -> resources.pure_files(overall_syntax, info.dir)) ::
   241                     thy_deps.loaded_files.filterNot(p => p._1 == Thy_Header.PURE)
   242                 }
   243                 else thy_deps.loaded_files
   244               }
   245               else Nil
   246 
   247             val session_files =
   248               (theory_files ::: loaded_files.flatMap(_._2) :::
   249                 info.document_files.map(file => info.dir + file._1 + file._2)).map(_.expand)
   250 
   251             val imported_files = if (inlined_files) thy_deps.imported_files else Nil
   252 
   253             if (list_files)
   254               progress.echo(cat_lines(session_files.map(_.implode).sorted.map("  " + _)))
   255 
   256             if (check_keywords.nonEmpty) {
   257               Check_Keywords.check_keywords(
   258                 progress, overall_syntax.keywords, check_keywords, theory_files)
   259             }
   260 
   261             val session_graph_display: Graph_Display.Graph =
   262             {
   263               def session_node(name: String): Graph_Display.Node =
   264                 Graph_Display.Node("[" + name + "]", "session." + name)
   265 
   266               def node(name: Document.Node.Name): Graph_Display.Node =
   267               {
   268                 val qualifier = imports_base.theory_qualifier(name)
   269                 if (qualifier == info.name)
   270                   Graph_Display.Node(name.theory_base_name, "theory." + name.theory)
   271                 else session_node(qualifier)
   272               }
   273 
   274               val imports_subgraph =
   275                 sessions.imports_graph.restrict(sessions.imports_graph.all_preds(info.deps).toSet)
   276 
   277               val graph0 =
   278                 (Graph_Display.empty_graph /: imports_subgraph.topological_order)(
   279                   { case (g, session) =>
   280                       val a = session_node(session)
   281                       val bs = imports_subgraph.imm_preds(session).toList.map(session_node(_))
   282                       ((g /: (a :: bs))(_.default_node(_, Nil)) /: bs)(_.add_edge(_, a)) })
   283 
   284               (graph0 /: thy_deps.entries)(
   285                 { case (g, entry) =>
   286                     val a = node(entry.name)
   287                     val bs =
   288                       entry.header.imports.map({ case (name, _) => node(name) }).
   289                         filterNot(_ == a)
   290                     ((g /: (a :: bs))(_.default_node(_, Nil)) /: bs)(_.add_edge(_, a)) })
   291             }
   292 
   293             val known =
   294               Known.make(info.dir, List(imports_base),
   295                 theories = thy_deps.names,
   296                 loaded_files = loaded_files)
   297 
   298             val sources_errors =
   299               for (p <- session_files if !p.is_file) yield "No such file: " + p
   300 
   301             val base =
   302               Base(
   303                 pos = info.pos,
   304                 global_theories = global_theories,
   305                 loaded_theories = thy_deps.loaded_theories,
   306                 known = known,
   307                 overall_syntax = overall_syntax,
   308                 imported_sources = check_sources(imported_files),
   309                 sources = check_sources(session_files),
   310                 session_graph_display = session_graph_display,
   311                 errors = thy_deps.errors ::: sources_errors,
   312                 imports = Some(imports_base))
   313 
   314             session_bases + (info.name -> base)
   315           }
   316           catch {
   317             case ERROR(msg) =>
   318               cat_error(msg, "The error(s) above occurred in session " +
   319                 quote(info.name) + Position.here(info.pos))
   320           }
   321       })
   322 
   323     Deps(session_bases, Known.make(Path.current, session_bases.toList.map(_._2)))
   324   }
   325 
   326 
   327   /* base info */
   328 
   329   sealed case class Base_Info(
   330     session: String,
   331     sessions: T,
   332     errors: List[String],
   333     base: Base,
   334     infos: List[Info])
   335   {
   336     def check_base: Base = if (errors.isEmpty) base else error(cat_lines(errors))
   337   }
   338 
   339   def base_info(options: Options, session: String,
   340     dirs: List[Path] = Nil,
   341     ancestor_session: Option[String] = None,
   342     all_known: Boolean = false,
   343     focus_session: Boolean = false,
   344     required_session: Boolean = false): Base_Info =
   345   {
   346     val full_sessions = load(options, dirs = dirs)
   347     val global_theories = full_sessions.global_theories
   348 
   349     val selected_sessions = full_sessions.selection(Selection(sessions = List(session)))._2
   350     val info = selected_sessions(session)
   351     val ancestor = ancestor_session orElse info.parent
   352 
   353     val (session1, infos1) =
   354       if (required_session && ancestor.isDefined) {
   355         val deps = Sessions.deps(selected_sessions, global_theories)
   356         val base = deps(session)
   357 
   358         val ancestor_loaded =
   359           deps.get(ancestor.get) match {
   360             case None =>
   361               error("Bad ancestor " + quote(ancestor.get) + " for session " + quote(session))
   362             case Some(ancestor_base) => ancestor_base.loaded_theories.defined(_)
   363           }
   364 
   365         val required_theories =
   366           for {
   367             thy <- base.loaded_theories.keys
   368             if !ancestor_loaded(thy) && base.theory_qualifier(thy) != session
   369           }
   370           yield thy
   371 
   372         if (required_theories.isEmpty) (ancestor.get, Nil)
   373         else {
   374           val other_name = info.name + "_base(" + ancestor.get + ")"
   375           (other_name,
   376             List(
   377               make_info(info.options,
   378                 dir_selected = false,
   379                 dir = info.dir,
   380                 chapter = info.chapter,
   381                 Session_Entry(
   382                   pos = info.pos,
   383                   name = other_name,
   384                   groups = info.groups,
   385                   path = ".",
   386                   parent = ancestor,
   387                   description = "Required theory imports from other sessions",
   388                   options = Nil,
   389                   imports = info.imports,
   390                   theories = List((Nil, required_theories.map(thy => ((thy, Position.none), false)))),
   391                   document_files = Nil))))
   392         }
   393       }
   394       else (session, Nil)
   395 
   396     val full_sessions1 =
   397       if (infos1.isEmpty) full_sessions
   398       else load(options, dirs = dirs, infos = infos1)
   399 
   400     val select_sessions1 =
   401       if (focus_session) full_sessions1.imports_descendants(List(session1))
   402       else List(session1)
   403     val selected_sessions1 =
   404       full_sessions1.selection(Selection(sessions = select_sessions1))._2
   405 
   406     val sessions1 = if (all_known) full_sessions1 else selected_sessions1
   407     val deps1 = Sessions.deps(sessions1, global_theories)
   408     val base1 = if (all_known) deps1(session1).copy(known = deps1.all_known) else deps1(session1)
   409 
   410     Base_Info(session1, sessions1, deps1.errors, base1, infos1)
   411   }
   412 
   413 
   414   /* cumulative session info */
   415 
   416   sealed case class Info(
   417     name: String,
   418     chapter: String,
   419     dir_selected: Boolean,
   420     pos: Position.T,
   421     groups: List[String],
   422     dir: Path,
   423     parent: Option[String],
   424     description: String,
   425     options: Options,
   426     imports: List[String],
   427     theories: List[(Options, List[(String, Position.T)])],
   428     global_theories: List[String],
   429     document_files: List[(Path, Path)],
   430     meta_digest: SHA1.Digest)
   431   {
   432     def deps: List[String] = parent.toList ::: imports
   433 
   434     def timeout: Time = Time.seconds(options.real("timeout") * options.real("timeout_scale"))
   435   }
   436 
   437   def make_info(options: Options, dir_selected: Boolean, dir: Path, chapter: String,
   438     entry: Session_Entry): Info =
   439   {
   440     try {
   441       val name = entry.name
   442 
   443       if (name == "" || name == DRAFT) error("Bad session name")
   444       if (is_pure(name) && entry.parent.isDefined) error("Illegal parent session")
   445       if (!is_pure(name) && !entry.parent.isDefined) error("Missing parent session")
   446 
   447       val session_options = options ++ entry.options
   448 
   449       val theories =
   450         entry.theories.map({ case (opts, thys) => (session_options ++ opts, thys.map(_._1)) })
   451 
   452       val global_theories =
   453         for { (_, thys) <- entry.theories; ((thy, pos), global) <- thys if global }
   454         yield {
   455           val thy_name = Path.explode(thy).expand.base_name
   456           if (Long_Name.is_qualified(thy_name))
   457             error("Bad qualified name for global theory " +
   458               quote(thy_name) + Position.here(pos))
   459           else thy_name
   460         }
   461 
   462       val conditions =
   463         theories.flatMap(thys => space_explode(',', thys._1.string("condition"))).distinct.sorted.
   464           map(x => (x, Isabelle_System.getenv(x) != ""))
   465 
   466       val document_files =
   467         entry.document_files.map({ case (s1, s2) => (Path.explode(s1), Path.explode(s2)) })
   468 
   469       val meta_digest =
   470         SHA1.digest((name, chapter, entry.parent, entry.options, entry.imports,
   471           entry.theories_no_position, conditions, entry.document_files).toString)
   472 
   473       Info(name, chapter, dir_selected, entry.pos, entry.groups,
   474         dir + Path.explode(entry.path), entry.parent, entry.description, session_options,
   475         entry.imports, theories, global_theories, document_files, meta_digest)
   476     }
   477     catch {
   478       case ERROR(msg) =>
   479         error(msg + "\nThe error(s) above occurred in session entry " +
   480           quote(entry.name) + Position.here(entry.pos))
   481     }
   482   }
   483 
   484   object Selection
   485   {
   486     val empty: Selection = Selection()
   487     val all: Selection = Selection(all_sessions = true)
   488   }
   489 
   490   sealed case class Selection(
   491     requirements: Boolean = false,
   492     all_sessions: Boolean = false,
   493     base_sessions: List[String] = Nil,
   494     exclude_session_groups: List[String] = Nil,
   495     exclude_sessions: List[String] = Nil,
   496     session_groups: List[String] = Nil,
   497     sessions: List[String] = Nil)
   498   {
   499     def ++ (other: Selection): Selection =
   500       Selection(
   501         requirements = requirements || other.requirements,
   502         all_sessions = all_sessions || other.all_sessions,
   503         base_sessions = Library.merge(base_sessions, other.base_sessions),
   504         exclude_session_groups = Library.merge(exclude_session_groups, other.exclude_session_groups),
   505         exclude_sessions = Library.merge(exclude_sessions, other.exclude_sessions),
   506         session_groups = Library.merge(session_groups, other.session_groups),
   507         sessions = Library.merge(sessions, other.sessions))
   508 
   509     def apply(graph: Graph[String, Info]): (List[String], Graph[String, Info]) =
   510     {
   511       val bad_sessions =
   512         SortedSet((base_sessions ::: exclude_sessions ::: sessions).
   513           filterNot(graph.defined(_)): _*).toList
   514       if (bad_sessions.nonEmpty)
   515         error("Undefined session(s): " + commas_quote(bad_sessions))
   516 
   517       val excluded =
   518       {
   519         val exclude_group = exclude_session_groups.toSet
   520         val exclude_group_sessions =
   521           (for {
   522             (name, (info, _)) <- graph.iterator
   523             if graph.get_node(name).groups.exists(exclude_group)
   524           } yield name).toList
   525         graph.all_succs(exclude_group_sessions ::: exclude_sessions).toSet
   526       }
   527 
   528       val pre_selected =
   529       {
   530         if (all_sessions) graph.keys
   531         else {
   532           val select_group = session_groups.toSet
   533           val select = sessions.toSet ++ graph.all_succs(base_sessions)
   534           (for {
   535             (name, (info, _)) <- graph.iterator
   536             if info.dir_selected || select(name) || graph.get_node(name).groups.exists(select_group)
   537           } yield name).toList
   538         }
   539       }.filterNot(excluded)
   540 
   541       val selected =
   542         if (requirements) (graph.all_preds(pre_selected).toSet -- pre_selected).toList
   543         else pre_selected
   544 
   545       (selected, graph.restrict(graph.all_preds(selected).toSet))
   546     }
   547   }
   548 
   549   def make(infos: List[Info]): T =
   550   {
   551     def add_edges(graph: Graph[String, Info], kind: String, edges: Info => Traversable[String])
   552       : Graph[String, Info] =
   553     {
   554       def add_edge(pos: Position.T, name: String, g: Graph[String, Info], parent: String) =
   555       {
   556         if (!g.defined(parent))
   557           error("Bad " + kind + " session " + quote(parent) + " for " +
   558             quote(name) + Position.here(pos))
   559 
   560         try { g.add_edge_acyclic(parent, name) }
   561         catch {
   562           case exn: Graph.Cycles[_] =>
   563             error(cat_lines(exn.cycles.map(cycle =>
   564               "Cyclic session dependency of " +
   565                 cycle.map(c => quote(c.toString)).mkString(" via "))) + Position.here(pos))
   566         }
   567       }
   568       (graph /: graph.iterator) {
   569         case (g, (name, (info, _))) => (g /: edges(info))(add_edge(info.pos, name, _, _))
   570       }
   571     }
   572 
   573     val graph0 =
   574       (Graph.string[Info] /: infos) {
   575         case (graph, info) =>
   576           if (graph.defined(info.name))
   577             error("Duplicate session " + quote(info.name) + Position.here(info.pos) +
   578               Position.here(graph.get_node(info.name).pos))
   579           else graph.new_node(info.name, info)
   580       }
   581     val graph1 = add_edges(graph0, "parent", _.parent)
   582     val graph2 = add_edges(graph1, "imports", _.imports)
   583 
   584     new T(graph1, graph2)
   585   }
   586 
   587   final class T private[Sessions](
   588       val build_graph: Graph[String, Info],
   589       val imports_graph: Graph[String, Info])
   590   {
   591     def build_graph_display: Graph_Display.Graph = Graph_Display.make_graph(build_graph)
   592     def imports_graph_display: Graph_Display.Graph = Graph_Display.make_graph(imports_graph)
   593 
   594     def apply(name: String): Info = imports_graph.get_node(name)
   595     def get(name: String): Option[Info] =
   596       if (imports_graph.defined(name)) Some(imports_graph.get_node(name)) else None
   597 
   598     def global_theories: Map[String, String] =
   599       (Thy_Header.bootstrap_global_theories.toMap /:
   600         (for {
   601           (_, (info, _)) <- imports_graph.iterator
   602           thy <- info.global_theories.iterator }
   603          yield (thy, info)))({
   604             case (global, (thy, info)) =>
   605               val qualifier = info.name
   606               global.get(thy) match {
   607                 case Some(qualifier1) if qualifier != qualifier1 =>
   608                   error("Duplicate global theory " + quote(thy) + Position.here(info.pos))
   609                 case _ => global + (thy -> qualifier)
   610               }
   611           })
   612 
   613     def selection(select: Selection): (List[String], T) =
   614     {
   615       val (_, build_graph1) = select(build_graph)
   616       val (selected, imports_graph1) = select(imports_graph)
   617       (selected, new T(build_graph1, imports_graph1))
   618     }
   619 
   620     def build_descendants(names: List[String]): List[String] =
   621       build_graph.all_succs(names)
   622     def build_requirements(names: List[String]): List[String] =
   623       build_graph.all_preds(names).reverse
   624     def build_topological_order: List[Info] =
   625       build_graph.topological_order.map(apply(_))
   626 
   627     def imports_descendants(names: List[String]): List[String] =
   628       imports_graph.all_succs(names)
   629     def imports_requirements(names: List[String]): List[String] =
   630       imports_graph.all_preds(names).reverse
   631     def imports_topological_order: List[Info] =
   632       imports_graph.topological_order.map(apply(_))
   633 
   634     override def toString: String =
   635       imports_graph.keys_iterator.mkString("Sessions.T(", ", ", ")")
   636   }
   637 
   638 
   639   /* parser */
   640 
   641   val ROOT = Path.explode("ROOT")
   642   val ROOTS = Path.explode("ROOTS")
   643 
   644   private val CHAPTER = "chapter"
   645   private val SESSION = "session"
   646   private val IN = "in"
   647   private val DESCRIPTION = "description"
   648   private val OPTIONS = "options"
   649   private val SESSIONS = "sessions"
   650   private val THEORIES = "theories"
   651   private val GLOBAL = "global"
   652   private val DOCUMENT_FILES = "document_files"
   653 
   654   lazy val root_syntax =
   655     Outer_Syntax.init + "(" + ")" + "+" + "," + "=" + "[" + "]" + GLOBAL + IN +
   656       (CHAPTER, Keyword.THY_DECL) +
   657       (SESSION, Keyword.THY_DECL) +
   658       (DESCRIPTION, Keyword.QUASI_COMMAND) +
   659       (OPTIONS, Keyword.QUASI_COMMAND) +
   660       (SESSIONS, Keyword.QUASI_COMMAND) +
   661       (THEORIES, Keyword.QUASI_COMMAND) +
   662       (DOCUMENT_FILES, Keyword.QUASI_COMMAND)
   663 
   664   abstract class Entry
   665   sealed case class Chapter(name: String) extends Entry
   666   sealed case class Session_Entry(
   667     pos: Position.T,
   668     name: String,
   669     groups: List[String],
   670     path: String,
   671     parent: Option[String],
   672     description: String,
   673     options: List[Options.Spec],
   674     imports: List[String],
   675     theories: List[(List[Options.Spec], List[((String, Position.T), Boolean)])],
   676     document_files: List[(String, String)]) extends Entry
   677   {
   678     def theories_no_position: List[(List[Options.Spec], List[(String, Boolean)])] =
   679       theories.map({ case (a, b) => (a, b.map({ case ((c, _), d) => (c, d) })) })
   680   }
   681 
   682   private object Parser extends Parse.Parser with Options.Parser
   683   {
   684     private val chapter: Parser[Chapter] =
   685     {
   686       val chapter_name = atom("chapter name", _.is_name)
   687 
   688       command(CHAPTER) ~! chapter_name ^^ { case _ ~ a => Chapter(a) }
   689     }
   690 
   691     private val session_entry: Parser[Session_Entry] =
   692     {
   693       val option =
   694         option_name ~ opt($$$("=") ~! option_value ^^
   695           { case _ ~ x => x }) ^^ { case x ~ y => (x, y) }
   696       val options = $$$("[") ~> rep1sep(option, $$$(",")) <~ $$$("]")
   697 
   698       val global =
   699         ($$$("(") ~! $$$(GLOBAL) ~ $$$(")")) ^^ { case _ => true } | success(false)
   700 
   701       val theory_entry =
   702         position(theory_name) ~ global ^^ { case x ~ y => (x, y) }
   703 
   704       val theories =
   705         $$$(THEORIES) ~!
   706           ((options | success(Nil)) ~ rep1(theory_entry)) ^^
   707           { case _ ~ (x ~ y) => (x, y) }
   708 
   709       val document_files =
   710         $$$(DOCUMENT_FILES) ~!
   711           (($$$("(") ~! ($$$(IN) ~! (path ~ $$$(")"))) ^^
   712               { case _ ~ (_ ~ (x ~ _)) => x } | success("document")) ~
   713             rep1(path)) ^^ { case _ ~ (x ~ y) => y.map((x, _)) }
   714 
   715       command(SESSION) ~!
   716         (position(session_name) ~
   717           (($$$("(") ~! (rep1(name) <~ $$$(")")) ^^ { case _ ~ x => x }) | success(Nil)) ~
   718           (($$$(IN) ~! path ^^ { case _ ~ x => x }) | success(".")) ~
   719           ($$$("=") ~!
   720             (opt(session_name ~! $$$("+") ^^ { case x ~ _ => x }) ~
   721               (($$$(DESCRIPTION) ~! text ^^ { case _ ~ x => x }) | success("")) ~
   722               (($$$(OPTIONS) ~! options ^^ { case _ ~ x => x }) | success(Nil)) ~
   723               (($$$(SESSIONS) ~! rep1(session_name)  ^^ { case _ ~ x => x }) | success(Nil)) ~
   724               rep(theories) ~
   725               (rep(document_files) ^^ (x => x.flatten))))) ^^
   726         { case _ ~ ((a, pos) ~ b ~ c ~ (_ ~ (d ~ e ~ f ~ g ~ h ~ i))) =>
   727             Session_Entry(pos, a, b, c, d, e, f, g, h, i) }
   728     }
   729 
   730     def parse_root(path: Path): List[Entry] =
   731     {
   732       val toks = Token.explode(root_syntax.keywords, File.read(path))
   733       val start = Token.Pos.file(path.implode)
   734 
   735       parse_all(rep(chapter | session_entry), Token.reader(toks, start)) match {
   736         case Success(result, _) => result
   737         case bad => error(bad.toString)
   738       }
   739     }
   740   }
   741 
   742   def parse_root(path: Path): List[Entry] = Parser.parse_root(path)
   743 
   744   def parse_root_entries(path: Path): List[Session_Entry] =
   745     for (entry <- Parser.parse_root(path) if entry.isInstanceOf[Session_Entry])
   746     yield entry.asInstanceOf[Session_Entry]
   747 
   748   def read_root(options: Options, select: Boolean, path: Path): List[Info] =
   749   {
   750     var entry_chapter = "Unsorted"
   751     val infos = new mutable.ListBuffer[Info]
   752     parse_root(path).foreach {
   753       case Chapter(name) => entry_chapter = name
   754       case entry: Session_Entry =>
   755         infos += make_info(options, select, path.dir, entry_chapter, entry)
   756     }
   757     infos.toList
   758   }
   759 
   760   def parse_roots(roots: Path): List[String] =
   761   {
   762     for {
   763       line <- split_lines(File.read(roots))
   764       if !(line == "" || line.startsWith("#"))
   765     } yield line
   766   }
   767 
   768 
   769   /* load sessions from certain directories */
   770 
   771   private def is_session_dir(dir: Path): Boolean =
   772     (dir + ROOT).is_file || (dir + ROOTS).is_file
   773 
   774   private def check_session_dir(dir: Path): Path =
   775     if (is_session_dir(dir)) File.pwd() + dir.expand
   776     else error("Bad session root directory: " + dir.toString)
   777 
   778   def directories(dirs: List[Path], select_dirs: List[Path]): List[(Boolean, Path)] =
   779   {
   780     val default_dirs = Isabelle_System.components().filter(is_session_dir(_))
   781     (default_dirs ::: dirs).map((false, _)) ::: select_dirs.map((true, _))
   782   }
   783 
   784   def load(options: Options,
   785     dirs: List[Path] = Nil,
   786     select_dirs: List[Path] = Nil,
   787     infos: List[Info] = Nil): T =
   788   {
   789     def load_dir(select: Boolean, dir: Path): List[(Boolean, Path)] =
   790       load_root(select, dir) ::: load_roots(select, dir)
   791 
   792     def load_root(select: Boolean, dir: Path): List[(Boolean, Path)] =
   793     {
   794       val root = dir + ROOT
   795       if (root.is_file) List((select, root)) else Nil
   796     }
   797 
   798     def load_roots(select: Boolean, dir: Path): List[(Boolean, Path)] =
   799     {
   800       val roots = dir + ROOTS
   801       if (roots.is_file) {
   802         for {
   803           entry <- parse_roots(roots)
   804           dir1 =
   805             try { check_session_dir(dir + Path.explode(entry)) }
   806             catch {
   807               case ERROR(msg) =>
   808                 error(msg + "\nThe error(s) above occurred in session catalog " + roots.toString)
   809             }
   810           res <- load_dir(select, dir1)
   811         } yield res
   812       }
   813       else Nil
   814     }
   815 
   816     val roots =
   817       for {
   818         (select, dir) <- directories(dirs, select_dirs)
   819         res <- load_dir(select, check_session_dir(dir))
   820       } yield res
   821 
   822     val unique_roots =
   823       ((Map.empty[JFile, (Boolean, Path)] /: roots) { case (m, (select, path)) =>
   824         val file = path.canonical_file
   825         m.get(file) match {
   826           case None => m + (file -> (select, path))
   827           case Some((select1, path1)) => m + (file -> (select1 || select, path1))
   828         }
   829       }).toList.map(_._2)
   830 
   831     make(unique_roots.flatMap(p => read_root(options, p._1, p._2)) ::: infos)
   832   }
   833 
   834 
   835 
   836   /** heap file with SHA1 digest **/
   837 
   838   private val sha1_prefix = "SHA1:"
   839 
   840   def read_heap_digest(heap: Path): Option[String] =
   841   {
   842     if (heap.is_file) {
   843       val file = FileChannel.open(heap.file.toPath, StandardOpenOption.READ)
   844       try {
   845         val len = file.size
   846         val n = sha1_prefix.length + SHA1.digest_length
   847         if (len >= n) {
   848           file.position(len - n)
   849 
   850           val buf = ByteBuffer.allocate(n)
   851           var i = 0
   852           var m = 0
   853           do {
   854             m = file.read(buf)
   855             if (m != -1) i += m
   856           }
   857           while (m != -1 && n > i)
   858 
   859           if (i == n) {
   860             val prefix = new String(buf.array(), 0, sha1_prefix.length, UTF8.charset)
   861             val s = new String(buf.array(), sha1_prefix.length, SHA1.digest_length, UTF8.charset)
   862             if (prefix == sha1_prefix) Some(s) else None
   863           }
   864           else None
   865         }
   866         else None
   867       }
   868       finally { file.close }
   869     }
   870     else None
   871   }
   872 
   873   def write_heap_digest(heap: Path): String =
   874     read_heap_digest(heap) match {
   875       case None =>
   876         val s = SHA1.digest(heap).rep
   877         File.append(heap, sha1_prefix + s)
   878         s
   879       case Some(s) => s
   880     }
   881 
   882 
   883 
   884   /** persistent store **/
   885 
   886   object Session_Info
   887   {
   888     val session_name = SQL.Column.string("session_name").make_primary_key
   889 
   890     // Build_Log.Session_Info
   891     val session_timing = SQL.Column.bytes("session_timing")
   892     val command_timings = SQL.Column.bytes("command_timings")
   893     val theory_timings = SQL.Column.bytes("theory_timings")
   894     val ml_statistics = SQL.Column.bytes("ml_statistics")
   895     val task_statistics = SQL.Column.bytes("task_statistics")
   896     val errors = SQL.Column.bytes("errors")
   897     val build_log_columns =
   898       List(session_name, session_timing, command_timings, theory_timings,
   899         ml_statistics, task_statistics, errors)
   900 
   901     // Build.Session_Info
   902     val sources = SQL.Column.string("sources")
   903     val input_heaps = SQL.Column.string("input_heaps")
   904     val output_heap = SQL.Column.string("output_heap")
   905     val return_code = SQL.Column.int("return_code")
   906     val build_columns = List(sources, input_heaps, output_heap, return_code)
   907 
   908     val table = SQL.Table("isabelle_session_info", build_log_columns ::: build_columns)
   909   }
   910 
   911   def store(system_mode: Boolean = false): Store = new Store(system_mode)
   912 
   913   class Store private[Sessions](system_mode: Boolean)
   914   {
   915     /* file names */
   916 
   917     def database(name: String): Path = Path.basic("log") + Path.basic(name).ext("db")
   918     def log(name: String): Path = Path.basic("log") + Path.basic(name)
   919     def log_gz(name: String): Path = log(name).ext("gz")
   920 
   921 
   922     /* SQL database content */
   923 
   924     val xml_cache = new XML.Cache()
   925 
   926     def read_bytes(db: SQL.Database, name: String, column: SQL.Column): Bytes =
   927       db.using_statement(Session_Info.table.select(List(column),
   928         Session_Info.session_name.where_equal(name)))(stmt =>
   929       {
   930         val res = stmt.execute_query()
   931         if (!res.next()) Bytes.empty else res.bytes(column)
   932       })
   933 
   934     def read_properties(db: SQL.Database, name: String, column: SQL.Column): List[Properties.T] =
   935       Properties.uncompress(read_bytes(db, name, column), Some(xml_cache))
   936 
   937 
   938     /* output */
   939 
   940     val browser_info: Path =
   941       if (system_mode) Path.explode("~~/browser_info")
   942       else Path.explode("$ISABELLE_BROWSER_INFO")
   943 
   944     val output_dir: Path =
   945       if (system_mode) Path.explode("~~/heaps/$ML_IDENTIFIER")
   946       else Path.explode("$ISABELLE_OUTPUT")
   947 
   948     override def toString: String = "Store(output_dir = " + output_dir.expand + ")"
   949 
   950     def prepare_output() { Isabelle_System.mkdirs(output_dir + Path.basic("log")) }
   951 
   952 
   953     /* input */
   954 
   955     private val input_dirs =
   956       if (system_mode) List(output_dir)
   957       else {
   958         val ml_ident = Path.explode("$ML_IDENTIFIER").expand
   959         output_dir :: Path.split(Isabelle_System.getenv_strict("ISABELLE_PATH")).map(_ + ml_ident)
   960       }
   961 
   962     def find_database_heap(name: String): Option[(Path, Option[String])] =
   963       input_dirs.find(dir => (dir + database(name)).is_file).map(dir =>
   964         (dir + database(name), read_heap_digest(dir + Path.basic(name))))
   965 
   966     def find_database(name: String): Option[Path] =
   967       input_dirs.map(_ + database(name)).find(_.is_file)
   968 
   969     def heap(name: String): Path =
   970       input_dirs.map(_ + Path.basic(name)).find(_.is_file) getOrElse
   971         error("Unknown logic " + quote(name) + " -- no heap file found in:\n" +
   972           cat_lines(input_dirs.map(dir => "  " + dir.expand.implode)))
   973 
   974 
   975     /* session info */
   976 
   977     def write_session_info(
   978       db: SQL.Database,
   979       name: String,
   980       build_log: Build_Log.Session_Info,
   981       build: Build.Session_Info)
   982     {
   983       db.transaction {
   984         db.create_table(Session_Info.table)
   985         db.using_statement(
   986           Session_Info.table.delete(Session_Info.session_name.where_equal(name)))(_.execute)
   987         db.using_statement(Session_Info.table.insert())(stmt =>
   988         {
   989           stmt.string(1) = name
   990           stmt.bytes(2) = Properties.encode(build_log.session_timing)
   991           stmt.bytes(3) = Properties.compress(build_log.command_timings)
   992           stmt.bytes(4) = Properties.compress(build_log.theory_timings)
   993           stmt.bytes(5) = Properties.compress(build_log.ml_statistics)
   994           stmt.bytes(6) = Properties.compress(build_log.task_statistics)
   995           stmt.bytes(7) = Build_Log.compress_errors(build_log.errors)
   996           stmt.string(8) = build.sources
   997           stmt.string(9) = cat_lines(build.input_heaps)
   998           stmt.string(10) = build.output_heap getOrElse ""
   999           stmt.int(11) = build.return_code
  1000           stmt.execute()
  1001         })
  1002       }
  1003     }
  1004 
  1005     def read_session_timing(db: SQL.Database, name: String): Properties.T =
  1006       Properties.decode(read_bytes(db, name, Session_Info.session_timing), Some(xml_cache))
  1007 
  1008     def read_command_timings(db: SQL.Database, name: String): List[Properties.T] =
  1009       read_properties(db, name, Session_Info.command_timings)
  1010 
  1011     def read_theory_timings(db: SQL.Database, name: String): List[Properties.T] =
  1012       read_properties(db, name, Session_Info.theory_timings)
  1013 
  1014     def read_ml_statistics(db: SQL.Database, name: String): List[Properties.T] =
  1015       read_properties(db, name, Session_Info.ml_statistics)
  1016 
  1017     def read_task_statistics(db: SQL.Database, name: String): List[Properties.T] =
  1018       read_properties(db, name, Session_Info.task_statistics)
  1019 
  1020     def read_errors(db: SQL.Database, name: String): List[String] =
  1021       Build_Log.uncompress_errors(read_bytes(db, name, Session_Info.errors))
  1022 
  1023     def read_build(db: SQL.Database, name: String): Option[Build.Session_Info] =
  1024     {
  1025       if (db.tables.contains(Session_Info.table.name)) {
  1026         db.using_statement(Session_Info.table.select(Session_Info.build_columns,
  1027           Session_Info.session_name.where_equal(name)))(stmt =>
  1028         {
  1029           val res = stmt.execute_query()
  1030           if (!res.next()) None
  1031           else {
  1032             Some(
  1033               Build.Session_Info(
  1034                 res.string(Session_Info.sources),
  1035                 split_lines(res.string(Session_Info.input_heaps)),
  1036                 res.string(Session_Info.output_heap) match { case "" => None case s => Some(s) },
  1037                 res.int(Session_Info.return_code)))
  1038           }
  1039         })
  1040       }
  1041       else None
  1042     }
  1043   }
  1044 }