(* ------------------- VERSION 19     03.06.86 ------------------- *)
PACKET supervisor :                            (* Autor: J.Liedtke *)
 
 
 

LET ack           = 0 ,
    nak           = 1 ,
    error nak     = 2 ,

    system catalogue code        = 3 ,
    begin code                   = 4 ,
    end code                     = 5 ,
    break code                   = 6 ,
    rename code                  = 7 ,
    halt code                    = 8 ,
    password code                = 9 ,
    family password code         = 40 ,
    set autonom code             = 41 ,
    reset autonom code           = 42 ,
    define canal code            = 43 ,
    go back to old canal code    = 44 ,
    task of channel code         = 45 ,
    canal of channel code        = 46 ,
    set automatic startup code   = 47 ,
    reset automatic startup code = 48 ,

    continue code low            = 100 ,
    continue code high           = 132 ,

    system start code            = 100 ,
    define station code          = 32000 ,
    max station no               = 127 ,
 
    nil = 0 ,

    number of tasks       = 125 ,
 
    number of channels       = 32 ,
    highest terminal channel = 16 ,
    highest user channel     = 24 ,
    highest system channel   = 32 ,
    configurator channel     = 32 ,

    shutup and save code = 12 ,

    channel field         = 4 ,
    fromid field          = 11 ,
    nilchannel            = 0 ;



TASK VAR order task ;
INT VAR  order code ,
         channel nr ,
         channel index ;

DATASPACE VAR ds ;

BOUND STRUCT (TEXT tname, tpass, TASK task, PROCA start proc) VAR msg ;
BOUND TEXT VAR error msg ;

REAL VAR last rename time := 0.0 ;


TEXT VAR actual password, supply password ;

 
ROW highest terminal channel TASK VAR canal ;

ROW number of channels TASK VAR connected task ;

FOR channel index FROM 1 UPTO highest terminal channel REP
  canal (channel index) := niltask ;
PER ;
FOR channel index FROM 1 UPTO number of channels REP
  connected task (channel index) := niltask
PER ;


ROW number of tasks BOOL VAR autonom flag ;
ROW number of tasks BOOL VAR automatic startup flag ;
ROW number of tasks TEXT VAR task password ;

task password (1) := "-"  ;
task password (2) := "-"  ;

set clock (date ("09.06.86")) ;

TASK VAR dummy task ;
command dialogue (TRUE) ; 

ke ;     (* maintenance ke *) 

create son (myself, "SYSUR", dummy task, proca (PROC sysur)) ;

PROC sysur :

  disable stop ;
  begin ("ARCHIVE", PROC archive manager, dummy task) ;
  begin ("OPERATOR", PROC monitor, dummy task) ;
  begin ("conf", PROC configurator, dummy task) ;
  system manager

ENDPROC sysur ;

PROC configurator :

  page ;
  REP UNTIL yes("Archiv 'dev' eingelegt") PER;
  archive ("dev") ;
  fetch all (archive) ;
  release (archive) ;
  REP UNTIL yes ("save system") PER ;
  command dialogue (FALSE) ;
  save system ;
  command dialogue (TRUE) ;
  rename myself ("configurator") ;
  disable stop ;
  REP
    configuration manager ;
    clear error
  PER

ENDPROC configurator ;


erase last bootstrap source dataspace ;
channel (myself, 1) ;
command dialogue (TRUE) ;
IF yes("Leere Floppy eingelegt")
  THEN channel (myself, nilchannel) ;
       command dialogue (FALSE) ;
       sys op (shutup and save code)
  ELSE channel (myself, nilchannel) ;
       command dialogue (FALSE)
FI ;
supervisor ;
 
 
PROC supervisor :
 
  disable stop ;
  INT VAR old session := session ;
  REP
    wait (ds, order code, order task) ;
    IF is niltask (order task)
      THEN interrupt
    ELIF station (order task) = station (myself)
      THEN order from task
    FI 
  PER .

interrupt :
  IF order code = 0
    THEN IF old session <> session
           THEN disconnect all terminal tasks ;
                old session := session
         FI ;
         system start interrupt
    ELSE supervisor interrupt (canal (order code), order code,
                               connected task (order code)) 
  FI .

disconnect all terminal tasks :
  INT VAR i ;
  FOR i FROM 1 UPTO highest terminal channel REP
    TASK VAR id := connected task (i) ;
    IF NOT (is niltask (id) COR automatic startup flag (index (id))
            COR is niltask (canal (i))) 
      THEN break task
    FI
  PER .

break task :
  IF task direct connected to channel
    THEN channel (id, nilchannel) ;
         connected task (i) := niltask 
    ELSE disconnect if at terminal but overloaded by canal
  FI .

task direct connected to channel :
 pcb (id, channel field) <> nilchannel .

disconnect if at terminal but overloaded by canal :
  connected task (i) := niltask .

order from task :
  channel index := channel (order task) ;
  IF is command analyzer task
    THEN order from command analyzer (connected task (channel index))
    ELSE order from user task
  FI ;
  IF is error
    THEN send back error message
  FI .

is command analyzer task :
        channel index <> nilchannel
  CAND  channel index <= highest terminal channel
  CAND  order task = canal (channel index) .

send back error message :
  forget (ds) ;
  ds := nilspace ;
  error msg := ds ;
  CONCR (error msg) := error message ;
  clear error ;
  send (order task, error nak, ds) .

ENDPROC supervisor ;

PROC supervisor interrupt (TASK VAR command analyzer, INT CONST channel nr,
                           TASK VAR terminal task) :
 
  IF NOT is niltask (terminal task)
    THEN channel (terminal task, nilchannel)
  FI ;
  create command analyzer if necessary ;
  IF already at terminal
    THEN halt process (command analyzer)
    ELSE send acknowledge
  FI ;
  channel (command analyzer, channel nr) ;
  activate (command analyzer) .

create command analyzer if necessary :
  IF is niltask (command analyzer)
    THEN create son (myself, "-", command analyzer, proca (PROC analyze supervisor command))
  FI .

send acknowledge : 
  forget (ds) ;
  ds := nilspace ;
  send (command analyzer, ack, ds) .

already at terminal :  channel (command analyzer) = channel nr .

ENDPROC supervisor interrupt ;

PROC order from command analyzer (TASK VAR terminal task) :

enable stop ;
IF is continue                          THEN sv cmd continue 
ELIF order code = system catalogue code THEN task info cmd
ELIF order code = task of channel code  THEN sv cmd task of channel
ELSE SELECT order code OF  CASE ack :
                           CASE end code   : sv cmd end
                           CASE break code : sv cmd break
                           CASE halt code  : sv cmd halt 
                           OTHERWISE errorstop ("falscher Auftrag fuer Task ""SUPERVISOR""") 
     END SELECT ;
     channel (command analyzer, nilchannel)
FI ;

forget (ds) ;
IF NOT is niltask (terminal task) AND order code <> system catalogue code
  THEN channel (order task, nilchannel) ;
       channel (terminal task, channel index) ;
       activate (terminal task)
FI .

sv cmd task of channel :
  msg := ds ;
  msg.task := terminal task ;
  send (order task,ack, ds) ;
  LEAVE order from command analyzer .

sv cmd end :
  IF NOT is niltask (terminal task)
    THEN delete task (terminal task) ;
         terminal task := niltask
  FI .

sv cmd break :
  terminal task := niltask .

sv cmd continue :
  sv cmd break ;
  continue cmd by canal .

sv cmd halt :
  IF is niltask (terminal task)
    THEN errorstop ("keine Task angekoppelt")
    ELSE halt process (terminal task)
  FI .

is continue :
  order code > continue code low AND order code <= continue code high .

command analyzer : canal (channel index) .

ENDPROC order from command analyzer ;

PROC order from user task :

  enable stop ;
  SELECT order code OF
    CASE nak, error nak               : 
    CASE system catalogue code        : task info cmd
    CASE begin code                   : user begin cmd
    CASE end code                     : user end cmd
    CASE break code                   : user break cmd
    CASE rename code                  : user rename cmd
    CASE password code                : password cmd
    CASE family password code         : family password cmd
    CASE set autonom code             : set autonom cmd
    CASE reset autonom code           : reset autonom cmd
    CASE define canal code            : define new canal
    CASE go back to old canal code    : go back to old canal
    CASE task of channel code         : task of channel
    CASE canal of channel code        : canal of channel
    CASE set automatic startup code   : set automatic startup cmd
    CASE reset automatic startup code : reset automatic startup cmd
    OTHERWISE IF is continue
                THEN            user continue cmd
              ELIF is define station
                THEN            define new station
                  ELSE errorstop ("falscher Auftrag fuer Task ""SUPERVISOR""") 
              FI
  ENDSELECT .

user begin cmd :
  msg := ds ;
  create son (order task, new task name, new task, new start proc) ;
  send (order task, ack, ds) .

user end cmd :
  msg := ds ;
  TASK VAR to be erased := CONCR (msg).task ;
  IF task end permitted
    THEN delete task (to be erased)
    ELSE errorstop ("'end' unzulaessig")
  FI ;
  IF exists (order task)
    THEN send (order task, ack, ds)
    ELSE forget (ds)
  FI .

task end permitted :
  ( (task is dead AND system catalogue contains entry) OR exists (to be erased))
  CAND  (     to be erased = order task 
          COR to be erased < order task
          COR (order task < myself AND NOT (order task < to be erased)) ) .

task is dead :
  status (to be erased) > 6 .

system catalogue contains entry :
  task in catalogue (to be erased, index (to be erased)) .

user rename cmd :
  IF last rename was long ago
    THEN msg := ds ;
         name (order task, CONCR (msg).tname) ;
         update entry in connected task array ;
         send (order task, ack, ds) ;
         remember rename time
    ELSE send (order task, nak, ds)
  FI .

update entry in connected task array :
  IF channel (order task) <> nilchannel
    THEN connected task (channel (order task)) := order task
  FI .

remember rename time :
  last rename time := clock (1) .

last rename was long ago :  abs (clock (1) - last rename time) > 20.0 .

user break cmd :
  break order task ;
  send (order task, ack, ds) .

break order task :
  IF task direct connected to channel
    THEN channel (order task, nilchannel) ;
         terminal task := niltask
    ELSE disconnect if at terminal but overloaded by canal
  FI .

task direct connected to channel : channel index <> nilchannel .

terminal task :  connected task (channel index) .

disconnect if at terminal but overloaded by canal :
  INT VAR i ;
  FOR i FROM 1 UPTO highest terminal channel REP
    IF connected task (i) = order task
      THEN connected task (i) := niltask ;
           LEAVE disconnect if at terminal but overloaded by canal
    FI
  PER .

user continue cmd :
  INT CONST dest channel := order code - continue code low ;
  IF dest channel <= highest user channel OR order task < myself
    THEN IF NOT channel really existing
           THEN errorstop ("kein Kanal")
         ELIF dest channel is free OR task is already at dest channel
           THEN break order task ;
                continue (order task, dest channel) ;
                autonom flag (index (order task)) := FALSE ;
                send (order task, ack, ds) 
           ELSE errorstop ("Kanal belegt")
         FI
     ELSE errorstop ("ungueltiger Kanal")
   FI .

channel really existing :
  channel type (dest channel) <> 0 OR dest channel = configurator channel .

dest channel is free : 
  (is niltask (connected task (dest channel)) OR channel (connected task (dest channel)) = nilchannel)
  AND no canal active .

no canal active :
  dest channel > highest terminal channel    COR
  is niltask (canal (dest channel))          COR 
  channel (canal (dest channel)) = nilchannel .

task is already at dest channel :
  channel index = dest channel .


password cmd :
  msg := ds ;
  task password (index (order task)) := new task password ;
  forget (ds) ;
  ds := nilspace ;
  send (order task, ack, ds) .

family password cmd :
  msg := ds ;
  actual password := new task password ;
  supply password := task password (index (order task)) ;
  change pw of all sons where necessary (son (order task)) ;
  task password (index (order task)) := actual password ;
  forget (ds) ;
  ds := nilspace ;
  send (order task, ack, ds) .

set autonom cmd :
  autonom flag (index (order task)) := TRUE ;
  send (order task, ack, ds) .

reset autonom cmd :
  autonom flag (index (order task)) := FALSE ;
  send (order task, ack, ds) .
 
define new canal :
  IF order task < myself AND
     channel index > 0 AND channel index <= highest terminal channel CAND
     is niltask (canal (channel index))
    THEN canal (channel index) := order task ;
         connected task (channel index) := niltask ;
         send (order task, ack, ds)
    ELSE errorstop ("falscher Auftrag fuer Task ""SUPERVISOR""")
  FI .

go back to old canal :
  IF order task < myself AND
     channel index > 0 AND channel index <= highest terminal channel 
    THEN IF NOT is niltask (canal (channel index))
           THEN delete task (canal (channel index)) 
         FI ;
         send (order task, ack, ds)
    ELSE errorstop ("falscher Auftrag fuer Task ""SUPERVISOR""")
  FI .

task of channel :
  msg := ds ;
  channel nr := int (msg.tname) ;
  msg.task := channel task ;
  send (order task, ack, ds).

channel task :
  IF channel nr <= highest terminal channel
    THEN IF no command analyzer active
           THEN connected task (channel nr)
           ELSE canal (channel nr)
         FI
    ELSE connected task (channel nr)
  FI .

no command analyzer active :
  channel (canal (channel nr)) = nilchannel .

canal of channel :
  msg := ds ;
  channel nr := int (msg.tname) ;
  msg.task := canal (channel nr) ;
  send (order task, ack, ds).

set automatic startup cmd :
  automatic startup flag (index (order task)) := TRUE ;
  send (order task, ack, ds) .

reset automatic startup cmd :
  automatic startup flag (index (order task)) := FALSE ;
  send (order task, ack, ds) .
 
is continue :
  order code > continue code low AND order code <= continue code high .

new task name :     CONCR (msg).tname . 

new task      :     CONCR (msg).task .
 
new task password : subtext (CONCR (msg).tpass, 1, 100) .

new start proc :    CONCR (msg).start proc .
 
is define station :
  order code >= define station code AND order task < myself AND 
  order code <= define station code + max station no .

ENDPROC order from user task ;

PROC continue cmd by canal :

  access task name and password ;
  check password if necessary ;
  continue or send continue request ;
  channel (order task, nilchannel) .

access task name and password :
  msg := ds ;
  TASK CONST user task := task (CONCR (msg).tname) ;
  INT CONST task index := index (user task) ;
  actual password := task password (task index) ;
  supply password := CONCR (msg).tpass .

check password if necessary :
  IF actual password <> ""
    THEN IF supply password = ""
           THEN ask for password ;
                LEAVE continue cmd by canal
         ELIF actual password <> supply password OR actual password = "-"
           THEN errorstop ("Passwort falsch")
         FI
   FI .
ask for password :
  send (order task, password code, ds) .

continue or send continue request :
  IF autonom flag (task index)
    THEN send continue request to user task
    ELSE continue (user task, order code - continue code low)
  FI .
 
send continue request to user task :
  INT VAR request count , quit ;
  FOR request count FROM 1 UPTO 10 REP
    send (user task, order code, ds, quit) ;
    IF quit = ack
      THEN LEAVE send continue request to user task
    FI ;
    pause (3)
  PER ;
  errorstop ("Task antwortet nicht") .

ENDPROC continue cmd by canal ;

PROC continue (TASK CONST id, INT CONST channel nr) :

  IF NOT is niltask (id) CAND channel (id) <> channel nr
    THEN check whether not linked to another channel ;
         channel (id, channel nr) ;
         connected task (channel nr) := id ;
         prio (id, 0) ;
         activate (id)
  FI .

check whether not linked to another channel :
  INT VAR i ;
  FOR i FROM 1 UPTO number of channels REP
    IF connected task (i) = id
      THEN errorstop ("bereits an Kanal " + text (i) ) ;
           LEAVE continue
    FI
  PER .
 
ENDPROC continue ;

PROC task info cmd :

  forget (ds) ;
  ds := sys cat ;
  send (order task, ack, ds) .

ENDPROC task info cmd ;
 
PROC delete task (TASK CONST superfluous) :

  delete all sons of superfluous ;
  delete superfluous itself .

delete superfluous itself :
  update cpu time of father ;
  erase process (superfluous) ;
  delete (superfluous) ;
  erase terminal connection remark .

update cpu time of father :
  TASK CONST father task := father (superfluous) ;
  IF NOT is niltask (father task)
    THEN disable stop ;
         REAL CONST father time := clock (father task) + clock (superfluous);
         IF is error
           THEN clear error
           ELSE set clock (father task, father time)
         FI ;
         enable stop
  FI .

erase terminal connection remark :
  INT VAR i ;
  FOR i FROM 1 UPTO number of channels REP
    IF connected task (i) = superfluous
      THEN connected task (i) := niltask ;
           LEAVE erase terminal connection remark
    FI
  PER ;
  FOR i FROM 1 UPTO highest terminal channel REP
    IF canal (i) = superfluous
      THEN canal (i) := niltask ;
           LEAVE erase terminal connection remark
    FI
  PER .

delete all sons of superfluous :
  TASK VAR son task ;
  REP
    son task := son (superfluous) ;
    IF is niltask (son task)
      THEN LEAVE delete all sons of superfluous
    FI ;
    delete task (son task)
  PER .

ENDPROC delete task ;

PROC create son (TASK CONST father, TEXT CONST task name, TASK VAR new task, PROCA CONST start) :

  entry (father, task name, new task) ;
  autonom flag  (index (new task)) := FALSE ;
  automatic startup flag (index (new task)) := TRUE ;
  task password (index (new task)) := "" ;
  create (father, new task, privilege, start) .

privilege :
  IF new task < myself
    THEN 1
    ELSE 0
  FI .

ENDPROC create son ;


PROC system start interrupt :

  IF exists task ("configurator")
    THEN send system start message
  FI .

send system start message :
  ds := nilspace ;
  INT VAR request count, quit ;
  FOR request count FROM 1 UPTO 10 REP
    send (task ("configurator"), system start code, ds, quit) ;
    IF quit = ack
      THEN LEAVE send system start message
    FI ;
    pause (3)
  PER ;
  forget (ds) .

ENDPROC system start interrupt ;

PROC define new station :

  INT CONST station := order code - define station code ;
  INT VAR i ;
  FOR i FROM 1 UPTO highest terminal channel REP
    IF NOT is niltask (canal (i))
      THEN delete task (canal (i))
    FI
  PER ;
  define station (station) ;
  FOR i FROM 1 UPTO number of channels REP
    update (connected task (i))
  PER ;
  forget (ds) .

ENDPROC define new station ;

PROC change pw of all sons where necessary (TASK CONST first son) :

  TASK VAR actual task := first son ;
  WHILE NOT is niltask (actual task) REP
    change pw ;
    change pw of all sons where necessary (son (actual task));
    actual task := brother (actual task)
  PER.

  change pw :
    IF task password (index (actual task)) = supply password 
                        OR
       task password (index (actual task)) = ""
      THEN task password (index (actual task)) := actual password
    FI.

END PROC change pw of all sons where necessary ;

(******************* basic supervisor operations **********************)


PROC channel (TASK CONST id, INT CONST channel nr) :
  pcb (id, channel field, channel nr)
ENDPROC channel ;

INT PROC channel type (INT CONST channel nr) :
  disable stop ;
  channel (myself, channel nr) ;
  INT VAR type ;
  control (1, 0, 0, type) ;
  channel (myself, nilchannel) ;
  type
ENDPROC channel type ;

PROC erase last bootstrap source dataspace :

  disable stop ;
  errorstop ("") ;
  clear error

ENDPROC erase last bootstrap source dataspace ;

PROC set clock (TASK CONST id, REAL CONST clock value) :
  EXTERNAL 82
ENDPROC set clock ;

PROC sys op (INT CONST code) :
  EXTERNAL 90
END PROC sys op ;

PROC create (TASK CONST father, son, INT CONST priv, PROCA CONST start) :
  EXTERNAL 95
ENDPROC create ;
 
PROC pcb (TASK CONST id, INT CONST field, value) :
  EXTERNAL 105
ENDPROC pcb ;

PROC activate (TASK CONST id) :
  EXTERNAL 108
ENDPROC activate ;

PROC deactivate (TASK CONST id) :
  EXTERNAL 109
ENDPROC deactivate ;

PROC halt process (TASK CONST id) :
  EXTERNAL 110
ENDPROC halt process ;

PROC erase process (TASK CONST id) :
  EXTERNAL 112
ENDPROC erase process ;

ENDPACKET supervisor ;