LOTOS

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LOTOS

• Specifikaciju valodu pamati

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LOTOS ievada piezimes

• LOTOS Language of Temporal Ordering
  Specification, valoda notikumu temporala
  sakartojuma aprakstam
• Balstita uz procesu algebras idejam, lidzigi ka
  CCS
• LOTOS specifikacijas semantika sistemas
  komunikacijas speja, formali uzdota ar iezimeto
  pareju sistemam
• Komunikacija abpuseja atbildiba par notikumu
  (handshake)
• (Vaja) bisimulacijas ekvivalence ka procesu
  vienadiba
• Procesu paralela kompozicija vienadu notikumu
  sinhronizacija. Iespejama daudzpuseja
  sinhronizacija.
• Praktiski izmantojama telekomunikaciju protokolu
  aprakstam
• Ierobežojumu inkrementacija (constraint oriented
  spec.)
• ISO standarts
• Datu specifikacija ACT ONE, citas pieejas

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Bazes LOTOS darbibas izteiksmes

• B stop iB gB B1 B2 B1 g1,,
  gn B2 hide g1,,gn in B Pg1,,gn
  exit B1 gtgt B2 B1 gt B2
• G komunikacijas punktu (komunikacijas notikumu)
  kopa
• B1 B2 B1 B2 nav sinhronizacijas
• B1 B2 B1 G B2 sinhronizacija uz
  visiem notikumiem
• ? - Veiksmigas beigas (exit izpildes efekts)

Notikumi Lietotaja definetie Lietotaja un sistemas definetie
Redzamie G, g ? G G G ? ?, g ? G
Redzamie un neredzamie M G ? i, m ? M MG?i, ?, m?M
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Bazes LOTOS darbibu semantika (1)

• mB (m)gt B
• B1 (m)-gt B1 ? B1B2 (m)-gt B1
• B2 (m)-gt B2 ? B1B2 (m)-gt B2
• B1 (m)-gt B1, m?S ? B1SB2 (m)-gt B1SB2
• B2 (m)-gt B2, m?S ? B1SB2 (m)-gt B1SB2
• B1 (g)-gt B1, B2 (g)-gt B2, g ? S?? ?
  B1SB2 (g)-gt B1SB2
• Sinhronizacija nav uz i
• Neatkariga izpilde nav uz ?

Notikumi Lietotaja definetie Lietotaja un sistemas definetie
Redzamie G, g ? G G G ? ?, g ? G
Redzamie un neredzamie M G ? i, m ? M MG?i, ?, m?M
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Bazes LOTOS darbibu semantika (2)

• B (m)-gt B, m?g1,,gn ?hide g1,,gn in B
  (m)-gt hide g1,,gn in B
• B (g)-gt B, g?g1,,gn ?hide g1,,gn in B
  (i)-gt hide g1,,gn in B
• process Pg1,,gn BP endproc,
• BPg1/g1,g2/g2,,gn/gn (m)-gt B
  ? Pg1,g2,,gn (m)-gt B

Notikumi Lietotaja definetie Lietotaja un sistemas definetie
Redzamie G, g ? G G G ? ?, g ? G
Redzamie un neredzamie M G ? i, m ? M MG?i, ?, m?M
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Bazes LOTOS darbibu semantika (3)

• exit (?)-gt stop
• B1 (m)-gt B1 ? B1gtgtB2 (m)-gt B1gtgtB2
• B1 (?)-gt B1 ? B1gtgtB2 (i)-gt B2
• B1 (m)-gt B1 ? B1gtB2 (m)-gt B1gtB2
• B1 (?)-gt B1 ? B1gtB2 (?)-gt B1
• B2 (m)-gt B2 ? B1gtB2 (m)-gt B2

Notikumi Lietotaja definetie Lietotaja un sistemas definetie
Redzamie G, g ? G G G ? ?, g ? G
Redzamie un neredzamie M G ? i, m ? M MG?i, ?, m?M
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Bazes LOTOS piemers

• process Max3in1, in2, in3, out
• hide mid in
• ( Max2in1, in2, mid
• mid
• Max2mid, in3, out )
• where
• process Max2a, b, c
• a b c stop
• b a c stop
• endproc
• endproc

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Piemers komunikacijas protokola fragments

• process SenderConReq,ConCnf,DatReq,DisReq
  Connection_PhaseConReq,ConCnf
  gtgt Data_PhaseDatReq,DisReq
• where process Connection_PhaseConReq,ConCnf
  ConReq ConCnf exitendprocprocess
  Data_PhaseDatReq,DisReq (DatReq
  Data_PhaseDatReq,DisReq DisReq
  stop)endproc
• endproc

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Datu komunikacija valoda LOTOS ievads

• type Bool is Datu tipi, aprakstiti valoda ACT
  ONE (vai cita)sorts boolopns TRUE, FALSE -gt
  bool NOT bool -gt bool AND, OR bool,
  bool -gt bool, eqns ofsort bool forall bbool
  NOT(TRUE) FALSE NOT(NOT(b)) b b AND
  TRUE b,
• endtype
• g ?xnatxgt3 g1 !x stop
• hide g in g ?xnatxltmax B1(x) g g
  ?ynatygtmin B2(y)
• g a1, a2, an notikums ar atributiem a1, a2,
  an
• Katrs atributs !E vai ?xt (var but papildus
  nosacijumi)

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Datu komunikacija valoda LOTOS

• g a1, a2, an notikums ar atributiem a1, a2,
  an
• Katrs atributs !E vai ?xt (var but papildus
  nosacijumi)
• g !E B (gltval(E)gt)-gt B vertibas
  deklaracija
• g ?xt B(x) (gltvgt)-gt B(v) mainiga
  deklaracija
• Sinhronizacija, komunikacija
• B1 (gltv1,,vngt)-gt B1, B2 (gltv1,,vngt)-gt B2
• ? B1gB2 (gltv1,,vngt)-gt B1gB2
• Situacija Nosacijums Efekts
• g !E1 g !E2 val(E1)val(E2)
• g !E g ?xt val(E)t xval(E)
• g ?xt g ?yu tu xyvt

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Datu apstrades izteiksmes

• cond_1 -gt process_1 xgt0 -gt process_1
• cond_2 -gt process_2 x5 -gt process_2
• ... xlt9 -gt process_3
• cond_n -gt process_n
• Var izpildit jebkuru vienu no procesiem, kam
  speka atbilstošais nosacijums
• choice xnat B(x)
• x izvele notiek, veicot pirmo redzamo vai
  neredzamo darbibu procesa B(x)
• g ?xt B(x) ekvivalents ar choice xt g!x
  B(x)
• Autonoma x izvele choice xt i B(x)
• Autonoma x izvele choice xt g B(x)
• choice x1t1,,xntn B(x1,,xn) Vairaku
  mainigo izvele
• choice g in a1,,an Processg() Notikuma
  veida izvele, Processg() process ar notikuma
  vardu ka parametru

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Datu apstrade piemers, funkcionalitate

• process compare inp, out (min, max int)
  noexit inp ?xint(min lt x lt max -gt out !x
  compare inp, out (min, max) x lt min
  -gt out !min compare inp, out (x, max)
  x gt max -gt out !max compare inp, out
  (min, x)) endproc
• noexit funkcionalitate, procesam nav
  paredzeta veiksmigu beigu iespeja
• exit procesam ir paredzeta veiksmigu beigu
  iespeja
• exit(t1,,tn) procesam ir paredzeta veiksmigu
  beigu iespeja, nododot parametrus ar tipiem
  t1,,tn virkne sekojošam procesam
• B1 gtgt accept x1t1,,xntn in B2 virkne nodoto
  vertibu pienemšanas konstrukcija Virknes
  konstrukcijas gadijuma nepieciešams, lai
  funkcionalitates butu atbilstošas.

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Specifikacijas piemers

• Specification Max3in1,in2,in3,out noexittype
  natural is sorts nat opns zero -gt
  nat succ nat -gt nat largest nat,nat -gt
  nateqns ofsort nat forall x,y
  nat largest(zero,x)x largest(x,y)
  largest(y,x) largest(succ(x),succ(y))succ(larges
  t(x,y))endtypebehaviour hide mid in
  (Max2in1,in2,mid mid Max2mid,in3,out)
  where process Max2a,b,c noexit a
  ?xnat b ?ynat c !largest(x,y) stop b
  ?ynat a ?xnat c !largest(x,y) stop
  endproc
• endspec
• Apstaiga 3 ieejas in1, in2, in3, uz katras no
  tam sanem pa skaitlim, pec tam uz out izdod
  lielako no šiem skaitliem.

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Specifikacijas struktura (pamats)

• specification specname gate list (parameter
  list) functionalitytype definitions šis ir
  globalas tipu definicijas, tas var izmantot
  specifikacijas parametru tipu noradišanabehaviour
  behaviour expression
• where type definitions
• process definitions
• endspec
• process procname gate list (parameter
  list) functionality behaviour
  expressionwhere type definitions process
  definitions
• endproc

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Specifikacija ierobežojumu pieaugšanas stila,
piemers

• specification Daemon_Game usr noexit
• library Boolean, Set, NaturalNumber endlib
• behaviour Login_Check usr (empty) Sessions
  usr
• where type Integer is sorts int opns 0 -gt
  int inc,dec int -gt int eqns ofsort int
  forall nint inc(dec(n))n dec(inc(n))n
  endtypetype Signal is Integer sorts sig_sort
  opns newgame, endgame, probe, win, lose, result
  -gtsig_sort score int -gt sig_sort
  endtypetype Identifier is NaturalNumber renamed
  by sortnames id-sort for nat endtypetype
  Identifier_set is Set actualizedby Identifier
  using sortnames id_sort for elem id_set_sort
  for setendtype

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Specifikacija ierobežojumu pieaugšanas stila,
piemers

• behaviour Login_Check usr (empty) Sessions
  usr
• where
• process Login_Checkusr(used_id_set
  id_set_sort) noexit
• usr ?idid_sort !newgame id NotIn
  used_id_set Login_Checkusr
  (insert(id,used_id_set))
• usr ?idid_sort !endgame id IsIn
  used_id_set Login_Checkusr
  (remove(id,used_id_set))
• usr ?idid_sort !probe id IsIn
  used_id_set Login_Checkusr (used_id_set)
• usr ?idid_sort !win id IsIn used_id_set Logi
  n_Checkusr (used_id_set)
• usr ?idid_sort !lose id IsIn
  used_id_set Login_Checkusr (used_id_set)
• usr ?idid_sort !result id IsIn
  used_id_set Login_Checkusr (used_id_set)
• choice xint usr ?idid_sort !score(x)
  id IsIn used_id_set Login_Checkusr
  (used_id_set)
• endproc

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Specifikacija ierobežojumu pieaugšanas stila,
piemers

• behaviour Login_Check usr (empty) Sessions
  usr
• where
• process Sessions usr noexit
• (usr ?idid_sort !newgame ( Gameusr(id,0)
  gt usr !id !endgame stop)) Sessions usr
• where
• process Gameusr(idid_sort, totalint) noexit
  
• usr !id !probe( i usr !id !win Game usr
  (id, inc(total)) i usr !id !lose Game usr
  (id, dec(total)) )
• usr !id !resultusr !id !score (total) Game
  usr (id, total)
• endproc
• endproc ( Sessions )
• endspec