diff options
Diffstat (limited to 'docs/examples/pilib')
-rw-r--r-- | docs/examples/pilib/elasticBuffer.scala | 77 | ||||
-rw-r--r-- | docs/examples/pilib/handover.scala | 186 | ||||
-rw-r--r-- | docs/examples/pilib/mobilePhoneProtocol.scala | 172 | ||||
-rw-r--r-- | docs/examples/pilib/piNat.scala | 89 | ||||
-rw-r--r-- | docs/examples/pilib/rwlock.scala | 329 | ||||
-rw-r--r-- | docs/examples/pilib/scheduler.scala | 150 | ||||
-rw-r--r-- | docs/examples/pilib/semaphore.scala | 72 | ||||
-rw-r--r-- | docs/examples/pilib/twoPlaceBuffer.scala | 67 |
8 files changed, 0 insertions, 1142 deletions
diff --git a/docs/examples/pilib/elasticBuffer.scala b/docs/examples/pilib/elasticBuffer.scala deleted file mode 100644 index c173735dbb..0000000000 --- a/docs/examples/pilib/elasticBuffer.scala +++ /dev/null @@ -1,77 +0,0 @@ -package examples.pilib - -object elasticBuffer { - - import scala.concurrent.pilib._ - - /** - * Recursive type for channels that carry a "String" channel and - * an object of the type we define. - */ - class MetaChan extends Chan[Tuple2[Chan[String], MetaChan]] - - def Buffer(put: Chan[String], get: Chan[String]): Unit = { - - /** - * An empty buffer cell, ready to pass on (o,r) to the left. - */ - def Bl(i:Chan[String], l: MetaChan, - o: Chan[String], r: MetaChan): unit = - choice ( - l((o,r)) * (System.out.println("Removed one cell.")), - i * (inp => Cl(i, l, o, r, inp)) - ) - - /** - * A buffer cell containing a value, ready to receive (o,r) from the right. - */ - def Cl(i: Chan[String], l: MetaChan, - o: Chan[String], r: MetaChan, content: String): Unit = - choice ( - o(content) * (Bl(i,l,o,r)), - i * (inp => Dl(i,l,o,r,content, inp)), - r * ( { case (newo, newr) => Cl(i,l,newo,newr,content) }) - ) - - /** - * Two joined buffer cells, of type Cl - */ - def Dl(i: Chan[String], l: MetaChan, - o: Chan[String], r: MetaChan, - content: String, inp: String): Unit = { - val newlr = new MetaChan - val newio = new Chan[String] - spawn < Cl(i, l, newio, newlr, inp) | Cl(newio, newlr, o, r, content) > - } - - // l and r channels for the leftmost and rightmost cell, respectively. - val unused1 = new MetaChan - val unused2 = new MetaChan - - Bl(put, unused1, get, unused2) - } - - val random = new java.util.Random() - - def Producer(n: int, put: Chan[String]): Unit = { - Thread.sleep(1 + random.nextInt(1000)) - val msg = "object " + n - put.write(msg) - System.out.println("Producer gave " + msg) - Producer(n + 1, put) - } - - def Consumer(get: Chan[String]): Unit = { - Thread.sleep(1 + random.nextInt(1000)) - val msg = get.read - System.out.println("Consumer took " + msg) - Consumer(get) - } - - def main(args: Array[String]): Unit = { - val put = new Chan[String] - val get = new Chan[String] - spawn < Producer(0, put) | Consumer(get) | Buffer(put, get) > - } - -} diff --git a/docs/examples/pilib/handover.scala b/docs/examples/pilib/handover.scala deleted file mode 100644 index 4e9a5670a0..0000000000 --- a/docs/examples/pilib/handover.scala +++ /dev/null @@ -1,186 +0,0 @@ -package examples.pilib - -/** - * Handover example with recursive types for channels. - */ -object handoverRecursive { - - import concurrent.pilib._ - - val random = new java.util.Random() - - /** - * Recursive type for channels that carry a channel "unit" and - * an object of the type we define. - */ - class Switch extends Chan[Tuple2[Chan[unit], Switch]] - - /** - * Car. - */ - def Car(talk: Chan[unit], switch: Switch): unit = - choice ( - switch * ({ case (t,s) => Car(t, s) }), - talk(()) * ( { - Thread.sleep(1 + random.nextInt(1000)); - System.out.println("Car emitted a message."); - Car(talk, switch) - }) - ); - - /** - * Control center. - */ - def Control(talk1: Chan[unit], switch1: Switch, - gain1: Switch, lose1: Switch, - talk2: Chan[unit], switch2: Switch, - gain2: Switch, lose2: Switch): unit - = { - def Control1: unit= { - Thread.sleep(1 + random.nextInt(1000)); - lose1.write((talk2, switch2)); - gain2.write((talk2, switch2)); - Control2 - } - def Control2: unit = { - Thread.sleep(1 + random.nextInt(1000)); - lose2.write((talk1, switch1)); - gain1.write((talk1, switch1)); - Control1 - } - Control1 - } - - /** - * Active transmitter. - */ - def ActiveTransmitter(id: String, talk: Chan[unit], switch: Switch, - gain: Switch, lose: Switch): unit - = - choice ( - talk * (x => { - System.out.println(id + " received a message.") - ActiveTransmitter(id, talk, switch, gain, lose) - }), - lose * ({ case (t, s) => { - switch.write((t, s)) - IdleTransmitter(id, gain, lose) - }}) - ); - - /** - * Idle transmitter. - */ - def IdleTransmitter(id: String, gain: Switch, lose: Switch): unit = { - val (t, s) = gain.read; - ActiveTransmitter(id, t, s, gain, lose) - } - - def main(args: Array[String]): unit = { - val talk1 = new Chan[unit] - val switch1 = new Switch - val gain1 = new Switch - val lose1 = new Switch - val talk2 = new Chan[unit] - val switch2 = new Switch - val gain2 = new Switch - val lose2 = new Switch - spawn < - Car(talk1, switch1) | - ActiveTransmitter("Transmitter 1", talk1, switch1, gain1, lose1) | - IdleTransmitter("Transmitter 2", gain2, lose2) | - Control(talk1, switch1, gain1, lose1, talk2, switch2, gain2, lose2) > - } -} - -/** -* Handover example with type casts. -*/ -object handoverCast { - - import concurrent.pilib._; - - val random = new java.util.Random(); - - /** - * Car. - */ - def Car(talk: Chan[Any], switch: Chan[Any]): unit = - choice ( - switch * (o => { - val (t,s) = o.asInstanceOf[Tuple2[Chan[Any],Chan[Any]]]; - Car(t, s) - }), - talk(()) * ( { - Thread.sleep(1 + random.nextInt(1000)); - System.out.println("Car emitted a message."); - Car(talk, switch) - }) - ); - - /** - * Control center. - */ - def Control(talk1: Chan[Any], switch1: Chan[Any], - gain1: Chan[Any], lose1: Chan[Any], - talk2: Chan[Any], switch2: Chan[Any], - gain2: Chan[Any], lose2: Chan[Any]): unit - = { - def Control1: unit = { - Thread.sleep(1 + random.nextInt(1000)); - lose1.write((talk2, switch2)); - gain2.write((talk2, switch2)); - Control2 - } - def Control2: unit = { - Thread.sleep(1 + random.nextInt(1000)); - lose2.write((talk1, switch1)); - gain1.write((talk1, switch1)); - Control1 - } - Control1 - } - - /** - * Active transmitter. - */ - def ActiveTransmitter(id: String, talk: Chan[Any], switch: Chan[Any], - gain: Chan[Any], lose: Chan[Any]): unit - = - choice ( - talk * (x => { - System.out.println(id + " received a message.") - ActiveTransmitter(id, talk, switch, gain, lose) - }), - lose * (o => { - val (t, s) = o.asInstanceOf[Tuple2[Chan[Any],Chan[Any]]] - switch.write((t, s)) - IdleTransmitter(id, gain, lose) - }) - ) - - /** - * Idle transmitter. - */ - def IdleTransmitter(id: String, gain: Chan[Any], lose: Chan[Any]): unit = { - val (t, s) = gain.read.asInstanceOf[Tuple2[Chan[Any],Chan[Any]]] - ActiveTransmitter(id, t, s, gain, lose) - } - - def main(args: Array[String]): unit = { - val talk1 = new Chan[Any] - val switch1 = new Chan[Any] - val gain1 = new Chan[Any] - val lose1 = new Chan[Any] - val talk2 = new Chan[Any] - val switch2 = new Chan[Any] - val gain2 = new Chan[Any] - val lose2 = new Chan[Any] - spawn < - Car(talk1, switch1) | - ActiveTransmitter("Transmitter 1", talk1, switch1, gain1, lose1) | - IdleTransmitter("Transmitter 2", gain2, lose2) | - Control(talk1, switch1, gain1, lose1, talk2, switch2, gain2, lose2) > - } - -} diff --git a/docs/examples/pilib/mobilePhoneProtocol.scala b/docs/examples/pilib/mobilePhoneProtocol.scala deleted file mode 100644 index e8c0ac1dc4..0000000000 --- a/docs/examples/pilib/mobilePhoneProtocol.scala +++ /dev/null @@ -1,172 +0,0 @@ -package examples.pilib - -/** -* Mobile phone protocol. -* Equivalent to a three-place buffer. -* @see Bjoern Victor "A verification tool for the polyadic pi-calculus". -*/ -object mobilePhoneProtocol { - - import concurrent.pilib._ - - val random = new java.util.Random() - - // Internal messages exchanged by the protocol. - trait Message - - // Predefined messages used by the protocol. - case class Data() extends Message; - case class HoCmd() extends Message; // handover command - case class HoAcc() extends Message; // handover access - case class HoCom() extends Message; // handover complete - case class HoFail() extends Message; // handover fail - case class ChRel() extends Message; // release - case class Voice(s: String) extends Message; // voice - case class Channel(n: Chan[Message]) extends Message; // channel - - def MobileSystem(in: Chan[String], out: Chan[String]): unit = { - - def CC(fa: Chan[Message], fp: Chan[Message], l: Chan[Channel]): unit = - choice ( - in * (v => { fa.write(Data()); fa.write(Voice(v)); CC(fa, fp, l) }) - , - l * (m_new => { - fa.write(HoCmd()); - fa.write(m_new); - choice ( - fp * ({ case HoCom() => { - System.out.println("Mobile has moved from one cell to another"); - fa.write(ChRel()); - val Channel(m_old) = fa.read; - l.write(Channel(m_old)); - CC(fp, fa, l) - }}) - , - fa * ({ case HoFail() => { - System.out.println("Mobile has failed to move from one cell to another"); - l.write(m_new); - CC(fa, fp, l) - }}) - ) - }) - ); - - /* - * Continuously orders the MSC to switch the MS to the non-used BS. - */ - def HC(l: Chan[Channel], m: Chan[Message]): unit = { - Thread.sleep(1 + random.nextInt(1000)); - l.write(Channel(m)); - val Channel(m_new) = l.read; - HC(l, m_new) - } - - /** - * Mobile switching center. - */ - def MSC(fa: Chan[Message], fp: Chan[Message], m: Chan[Message]): unit = { - val l = new Chan[Channel]; - spawn < HC(l, m) | CC(fa, fp, l) > - } - - /** - * Active base station. - */ - def BSa(f: Chan[Message], m: Chan[Message]): unit = - (f.read) match { - case Data() => { - val v = f.read; - m.write(Data()); - m.write(v); - BSa(f, m) - } - case HoCmd() => { - val v = f.read; - m.write(HoCmd()); - m.write(v); - choice ( - f * ({ case ChRel() => { - f.write(Channel(m)); - BSp(f, m) - }}) - , - m * ({ case HoFail() => { - f.write(HoFail()); - BSa(f, m) - }}) - ) - } - }; - - /** - * Passive base station. - */ - def BSp(f: Chan[Message], m: Chan[Message]): unit = { - val HoAcc = m.read - f.write(HoCom()) - BSa(f, m) - } - - /** - * Mobile station. - */ - def MS(m: Chan[Message]): unit = - (m.read) match { - case Data() => { - val Voice(v) = m.read; - out.write(v); - MS(m) - } - case HoCmd() => - (m.read) match { - case Channel(m_new) => { - if (random.nextInt(1) == 0) - choice ( m_new(HoAcc()) * (MS(m_new)) ); - else - choice ( m(HoFail()) * (MS(m)) ); - } - } - }; - - def P(fa: Chan[Message], fp: Chan[Message]): unit = { - val m = new Chan[Message]; - spawn < MSC(fa, fp, m) | BSp(fp, m) > - } - - def Q(fa: Chan[Message]): unit = { - val m = new Chan[Message]; - spawn < BSa(fa, m) | MS(m) > - } - - val fa = new Chan[Message]; - val fp = new Chan[Message]; - spawn < Q(fa) | P(fa, fp) >; - } - - //***************** Entry function ******************// - - def main(args: Array[String]): unit = { - - def Producer(n: Int, put: Chan[String]): unit = { - Thread.sleep(1 + random.nextInt(1000)); - val msg = "object " + n; - put.write(msg); - System.out.println("Producer gave " + msg); - Producer(n + 1, put) - } - - def Consumer(get: Chan[String]): unit = { - Thread.sleep(1 + random.nextInt(1000)); - val msg = get.read; - System.out.println("Consumer took " + msg); - Consumer(get) - } - - val put = new Chan[String]; - val get = new Chan[String]; - spawn < Producer(0, put) | Consumer(get) | MobileSystem(put, get) > - } - -} - - diff --git a/docs/examples/pilib/piNat.scala b/docs/examples/pilib/piNat.scala deleted file mode 100644 index c6d9bdaf5c..0000000000 --- a/docs/examples/pilib/piNat.scala +++ /dev/null @@ -1,89 +0,0 @@ -package examples.pilib - -import scala.concurrent.pilib._ - -/** Church encoding of naturals in the Pi-calculus */ -object piNat extends Application { - - /** Locations of Pi-calculus natural */ - class NatChan extends Chan[Tuple3[Chan[Unit], Chan[NatChan], Chan[NatChan]]] - - /** Zero */ - def Z(l: NatChan): Unit = choice ( - l * { case (z, sd, d) => z.write(()) } - ) - - /** Successor of Double */ - def SD(n: NatChan, l: NatChan): Unit = choice ( - l * { case (z, sd, d) => sd.write(n) } - ) - - /** Double */ - def D(n: NatChan, l: NatChan): Unit = choice ( - l * { case (z, sd, d) => d.write(n) } - ) - - /** Make "l" a location representing the natural "n" */ - def make(n: Int, l: NatChan): Unit = - if (n == 0) Z(l) - else if (n % 2 == 0) { val l1 = new NatChan; spawn < D(l1, l) >; make(n/2, l1) } - else { val l1 = new NatChan; spawn < SD(l1, l) >; make(n/2, l1) } - - /** Consume the natural "m" and put it successor at location "n" */ - def Succ(m: NatChan, n: NatChan) { - val z = new Chan[Unit] - val sd = new Chan[NatChan] - val d = new Chan[NatChan] - spawn < m.write((z, sd, d)) >; - choice ( - z * { x => make(1, n) }, - sd * { m1 => { val n1 = new NatChan; spawn < D(n1, n) >; Succ(m1, n1) } }, - d * { m1 => SD(m1, n) } - ) - } - - /** Consume the natural "l" and put two copies at locations "m" and "n" */ - def Copy(l: NatChan, m: NatChan, n: NatChan) { - val z = new Chan[Unit] - val sd = new Chan[NatChan] - val d = new Chan[NatChan] - spawn < l.write((z, sd, d)) >; - choice ( - z * { x => spawn < Z(m) >; Z(n) }, - sd * { l1 => { val m1 = new NatChan; val n1 = new NatChan; - spawn < SD(m1, m) | SD(n1, n) >; - Copy(l1, m1, n1) } }, - d * { l1 => { val m1 = new NatChan; val n1 = new NatChan; - spawn < D(m1, m) | D(n1, n) >; - Copy(l1, m1, n1) } } - ) - } - - /** Consume the natural at location "n" and return its value */ - def value(n: NatChan): Int = { - val z = new Chan[Unit] - val sd = new Chan[NatChan] - val d = new Chan[NatChan] - spawn < n.write((z, sd, d)) >; - choice ( - z * { x => 0 }, - sd * { n1 => 2 * value(n1) + 1 }, - d * { n1 => 2 * value(n1) } - ) - } - - // Test - val i = 42 - val l = new NatChan - val l1 = new NatChan - val l2 = new NatChan - val l3 = new NatChan - - spawn < - make(i, l) | - Copy(l, l1, l2) | - Succ(l2, l3) | - println("" + i + " = " + value(l1)) | - println("succ " + i + " = " + value(l3)) > - -} diff --git a/docs/examples/pilib/rwlock.scala b/docs/examples/pilib/rwlock.scala deleted file mode 100644 index bb1c26bdf2..0000000000 --- a/docs/examples/pilib/rwlock.scala +++ /dev/null @@ -1,329 +0,0 @@ -package examples.pilib - -/** -* From Pi to Scala: Semaphores, monitors, read/write locks. -* Readers/writers locks. -*/ -object rwlock { - - import scala.concurrent.pilib._ - - class Signal extends Chan[unit] { - def send = write(()) - def receive = read - } - - class CountLock { - private val busy = new Signal - def get = busy.send - def release = busy.receive - spawn < release > - } - - /** A binary semaphore - */ - class Lock { - private val busy = new Signal; - private val free = new Signal; - def get = busy.send; - def release = free.send; - spawn < (while (true) { - choice ( - busy * (x => free.receive), - free * (x => ()) - ) - }) > - } - - /** A monitor a la Java - */ - class JavaMonitor { - - private val lock = new Lock - - private var waiting: List[Signal] = Nil - - def Wait = { - val s = new Signal - waiting = s :: waiting - lock.release - s.receive - lock.get - } - - def Notify = - if (!waiting.isEmpty) { - waiting.head.send - waiting = waiting.tail - } - - def NotifyAll = - while (!waiting.isEmpty) { - waiting.head.send - waiting = waiting.tail - } - - def await(cond: => boolean): unit = - while (false == cond) (Wait) - } - - /* - class Buffer[a](size: Int) extends JavaMonitor with { - var in = 0, out = 0, n = 0; - val elems = new Array[a](size); - def put(x: a) = synchronized { - await(n < size); - elems(out) = x; - out = (out + 1) % size; - } - def get: a = synchronized { - await(n > 0); - val x = elems(in); - in = (in + 1) % size; - x - } - } - */ - - /** A readers/writers lock. */ - trait ReadWriteLock { - def startRead: unit - def startWrite: unit - def endRead: unit - def endWrite: unit - } - - /** - * A readers/writers lock, using monitor abstractions. - */ - class ReadWriteLock1 extends JavaMonitor with ReadWriteLock { - - private var nactive: int = 0 - private var nwriters: int = 0 - - def status = - System.out.println(nactive + " active, " + nwriters + " writers"); - - def startRead = synchronized { - await(nwriters == 0) - nactive = nactive + 1 - status - } - - def startWrite = synchronized { - nwriters = nwriters + 1 - await(nactive == 0) - nactive = 1 - status - } - - def endRead = synchronized { - nactive = nactive - 1 - if (nactive == 0) NotifyAll - status - } - - def endWrite = synchronized { - nwriters = nwriters - 1 - nactive = 0 - NotifyAll - status - } - } - - /** A readers/writers lock, using semaphores - */ - class ReadWriteLock2 extends ReadWriteLock { - - private var rc: int = 0 // reading readers - private var wc: int = 0 // writing writers - private var rwc: int = 0 // waiting readers - private var wwc: int = 0 // waiting writers - private val mutex = new Lock - private val rsem = new Lock - private val wsem = new Lock - - def startRead = { - mutex.get; - if (wwc > 0 || wc > 0) { - rwc = rwc + 1; - mutex.release; - rsem.get; - rwc = rwc - 1 - } - rc = rc + 1; - if (rwc > 0) rsem.release; - mutex.release - } - - def startWrite = { - mutex.get; - if (rc > 0 || wc > 0) { - wwc = wwc + 1; - mutex.release; - wsem.get; - wwc = wwc - 1 - } - wc = wc + 1; - mutex.release - } - - def endRead = { - mutex.get; - rc = rc - 1; - if (rc == 0 && wwc > 0) wsem.release; - mutex.release - } - - def endWrite = { - mutex.get; - wc = wc - 1; - if (rwc > 0) - rsem.release - else if (wwc > 0) wsem.release; - mutex.release - } - } - - /** A readers/writers lock, using channels, without priortities - */ - class ReadWriteLock3 extends ReadWriteLock { - - private val sr = new Signal - private val er = new Signal - private val sw = new Signal - private val ew = new Signal - - def startRead = sr.send - def startWrite = sw.send - def endRead = er.send - def endWrite = ew.send - - private def rwlock: unit = choice ( - sr * (x => reading(1)), - sw * (x => { ew.receive; rwlock }) - ) - - private def reading(n: int): unit = choice ( - sr * (x => reading(n+1)), - er * (x => if (n == 1) rwlock else reading(n-1)) - ) - - spawn < rwlock > - } - - /** Same, with sequencing - */ - class ReadWriteLock4 extends ReadWriteLock { - - private val rwlock = new ReadWriteLock3 - - private val sr = new Signal - private val ww = new Signal - private val sw = new Signal - - def startRead = sr.send - def startWrite = { ww.send; sw.send } - def endRead = rwlock.endRead - def endWrite = rwlock.endWrite - - private def queue: unit = choice ( - sr * (x => { rwlock.startRead ; queue }), - ww * (x => { rwlock.startWrite; sw.receive; queue }) - ) - - spawn < queue >; - } - - /** Readwritelock where writers always have priority over readers - */ - class ReadWriteLock5 extends ReadWriteLock { - - private val sr = new Signal - private val er = new Signal - private val ww = new Signal - private val sw = new Signal - private val ew = new Signal - - def startRead = sr.send - def startWrite = { ww.send; sw.send } - def endRead = er.send - def endWrite = ew.send - - private def Reading(nr: int, nw: int): unit = - if (nr == 0 && nw == 0) - choice ( - sr * (x => Reading(1, 0)), - ww * (x => Reading(0, 1)) - ) - else if (nr == 0 && nw != 0) { - sw.receive; - Writing(nw); - } - else if (nr != 0 && nw == 0) - choice ( - sr * (x => Reading(nr + 1, 0)), - er * (x => Reading(nr - 1, 0)), - ww * (x => Reading(nr, 1)) - ) - else if (nr != 0 && nw != 0) - choice ( - ww * (x => Reading(nr, nw + 1)), - er * (x => Reading(nr - 1, nw)) - ); - - private def Writing(nw: int): unit = choice ( - ew * (x => Reading(0, nw - 1)), - ww * (x => Writing(nw + 1)) - ); - - spawn < Reading(0, 0) >; - - } - - /** - * Main function. - */ - def main(args: Array[String]): unit = { - val random = new java.util.Random() - - def reader(i: int, rwlock: ReadWriteLock): unit = { - Thread.sleep(1 + random.nextInt(100)) - System.err.println("Reader " + i + " wants to read.") - rwlock.startRead - System.err.println("Reader " + i + " is reading.") - Thread.sleep(1 + random.nextInt(100)) - rwlock.endRead - System.err.println("Reader " + i + " has read.") - reader(i, rwlock) - } - - def writer(i: int, rwlock: ReadWriteLock): unit = { - Thread.sleep(1 + random.nextInt(100)) - System.err.println("Writer " + i + " wants to write.") - rwlock.startWrite - System.err.println("Writer " + i + " is writing.") - Thread.sleep(1 + random.nextInt(100)) - rwlock.endWrite - System.err.println("Writer " + i + " has written.") - writer(i, rwlock) - } - - val n = try { Integer.parseInt(args(0)) } catch { case _ => 0 } - if (n < 1 || 5 < n) { - Console.println("Usage: scala examples.pilib.rwlock <n> (n=1..5)") - exit - } - val rwlock = n match { - case 1 => new ReadWriteLock1 - case 2 => new ReadWriteLock2 - case 3 => new ReadWriteLock3 - case 4 => new ReadWriteLock4 - case 5 => new ReadWriteLock5 - } - List.range(0, 5) foreach (i => spawn < reader(i, rwlock) >) - List.range(0, 5) foreach (i => spawn < writer(i, rwlock) >) - } - -} - diff --git a/docs/examples/pilib/scheduler.scala b/docs/examples/pilib/scheduler.scala deleted file mode 100644 index fd8fd52600..0000000000 --- a/docs/examples/pilib/scheduler.scala +++ /dev/null @@ -1,150 +0,0 @@ -package examples.pilib - -import scala.concurrent.pilib._ - -object scheduler { - - /** - * Random number generator. - */ - val random = new util.Random() - - //***************** Scheduler ******************// - - /** - * A cell of the scheduler whose attached agent is allowed to start. - */ - def A(a: Chan[Unit], b: Chan[Unit])(d: Chan[Unit], c: Chan[Unit]) { - ///- ... complete here ... - choice ( a * { x => C(a, b)(d, c) }) - ///+ - } - - /** - * A cell of the scheduler in another intermediate state. - */ - def C(a: Chan[Unit], b: Chan[Unit])(d: Chan[Unit], c: Chan[Unit]) { - ///- ... complete here ... - choice (c * { x => B(a, b)(d, c) }) - ///+ - } - - /** - * A cell of the scheduler whose attached agent is allowed to finish. - */ - def B(a: Chan[Unit], b: Chan[Unit])(d: Chan[Unit], c: Chan[Unit]) { - ///- ... complete here ... - // choice (b * { x => D(a, b)(d, c) }) // incorrect naive solution - choice ( - b * { x => choice ( d(()) * A(a, b)(d, c) ) }, // b.'d.A - d(()) * (choice (b * { x => A(a, b)(d, c) })) // 'd.b.A - ) - ///+ - } - - /** - * A cell of the scheduler whose attached agent is not yet allowed to start. - */ - def D(a: Chan[Unit], b: Chan[Unit])(d: Chan[Unit], c: Chan[Unit]) { - ///- ... complete here ... - choice (d(()) * A(a, b)(d, c)) - ///+ - } - - //***************** Agents ******************// - - def agent(i: Int)(a: Chan[Unit], b: Chan[Unit]) { - // 50% chance that we sleep forever - if (i == 0 && random.nextInt(10) < 5) { - a.attach(x => println("Start and sleeps ----> " + i)) - Thread.sleep(random.nextInt(1000)) - a.write(()) - } - else { - a.attach(x => println("Start ----> " + i)) - b.attach(x => println("Stop -> " + i)) - Thread.sleep(random.nextInt(1000)) - a.write(()) - Thread.sleep(random.nextInt(1000)) - b.write(()) - agent(i)(a, b) - } - } - - //***************** Entry function ******************// - - /** - * Creates a scheduler for five agents (programs). - */ - - def main(args: Array[String]) { - val agentNb = 5 - val agents = List.range(0, agentNb) map agent - scheduleAgents(agents) - } - - //***************** Infrastructure *****************// - - /** - * A cell is modelled as a function that takes as parameters - * input and output channels and which returns nothing. - */ - type Cell = (Chan[Unit], Chan[Unit]) => Unit - - /** - * Creates a cell composed of two cells linked together. - */ - def join(cell1: Cell, cell2: Cell): Cell = - (l: Chan[Unit], r: Chan[Unit]) => { - val link = new Chan[Unit]; - spawn < cell1(l, link) | cell2(link, r) > - }; - - /** - * Links the output of a cell to its input. - */ - def close(cell: Cell) { - val a = new Chan[Unit] - cell(a, a) - } - - /** - * Creates a cell consisting of a chain of cells. - */ - def chain(cells: List[Cell]): Cell = - cells reduceLeft join - - /** - * Creates a cell consisting of a chain of cells. - */ - def makeRing(cells: List[Cell]): Unit = - close(chain(cells)) - - /** - * An agent is modelled as a function that takes as parameters channels to - * signal that it has started or finished. - */ - type Agent = (Chan[Unit], Chan[Unit]) => Unit - - /** - * Takes a list of agents and schedules them. - */ - def scheduleAgents(agents: List[Agent]) { - var firstAgent = true; - val cells = agents map (ag => { - val a = new Chan[Unit]; - val b = new Chan[Unit]; - spawn < ag(a, b) >; - (d: Chan[Unit], c: Chan[Unit]) => if (firstAgent) { - firstAgent = false; - A(a, b)(d, c) - } - else - D(a, b)(d, c) - }); - makeRing(cells) - } - -} - - diff --git a/docs/examples/pilib/semaphore.scala b/docs/examples/pilib/semaphore.scala deleted file mode 100644 index 951c90e8d4..0000000000 --- a/docs/examples/pilib/semaphore.scala +++ /dev/null @@ -1,72 +0,0 @@ -package examples.pilib - -import scala.concurrent.pilib._ - -/** Solution of exercise session 6 (first question). */ -object semaphore { - - class Signal extends Chan[Unit] { - def send = write(()) - def receive = read - } - - /** Interface. */ - trait Semaphore { - def get: Unit - def release: Unit - } - - /** First implementation. */ - class Sem1 extends Semaphore { - - private val g = new Signal - private val r = new Signal - - def get: Unit = g.send - def release: Unit = r.send - - private def Sched: Unit = choice ( - g * (x => { r.receive; Sched }), - r * (x => Sched) - ) - spawn< Sched > - } - - /** Second implementation. */ - class Sem2 extends Semaphore { - - private val a = new Signal - private val na = new Signal - - def get { a.receive; spawn< na.send > } - def release: Unit = choice ( - a * (x => spawn< a.send >), - na * (x => spawn< a.send >) - ) - spawn< a.send > - } - - /** Test program. */ - def main(args: Array[String]) { - val random = new util.Random() - val sem = new Sem2 - def mutex(p: => Unit) { sem.get; p; sem.release } - - spawn< { - Thread.sleep(1 + random.nextInt(100)); - mutex( { - println("a1"); - Thread.sleep(1 + random.nextInt(100)); - println("a2") - } ) - } | { - Thread.sleep(1 + random.nextInt(100)); - mutex( { - println("b1"); - Thread.sleep(1 + random.nextInt(100)); - println("b2") - } ) - } >; - } -} - diff --git a/docs/examples/pilib/twoPlaceBuffer.scala b/docs/examples/pilib/twoPlaceBuffer.scala deleted file mode 100644 index 255f70ca06..0000000000 --- a/docs/examples/pilib/twoPlaceBuffer.scala +++ /dev/null @@ -1,67 +0,0 @@ -package examples.pilib - -import scala.concurrent.pilib._ - -/** Two-place buffer specification and implementation. */ -object twoPlaceBuffer extends Application { - - /** - * Specification. - */ - def Spec[A](in: Chan[A], out: Chan[A]) { - - def B0: Unit = choice ( - in * (x => B1(x)) - ) - - def B1(x: A): Unit = choice ( - out(x) * (B0), - in * (y => B2(x, y)) - ) - - def B2(x: A, y: A): Unit = choice ( - out(x) * (B1(y)) - ) - - B0 - } - - /** - * Implementation using two one-place buffers. - */ - def Impl[A](in: Chan[A], out: Chan[A]) { - ///- ... complete here ... - // one-place buffer - def OnePlaceBuffer[A](in: Chan[A], out: Chan[A]) { - def B0: Unit = choice ( in * (x => B1(x)) ) - def B1(x: A): Unit = choice ( out(x) * (B0)) - B0 - } - val hidden = new Chan[A] - spawn < OnePlaceBuffer(in, hidden) | OnePlaceBuffer(hidden, out) > - ///+ - } - - val random = new util.Random() - - def Producer(n: Int, in: Chan[String]) { - Thread.sleep(random.nextInt(1000)) - val msg = "" + n - choice (in(msg) * {}) - Producer(n + 1, in) - } - - def Consumer(out: Chan[String]) { - Thread.sleep(random.nextInt(1000)) - choice (out * { msg => () }) - Consumer(out) - } - - val in = new Chan[String] - in.attach(s => println("put " + s)) - val out = new Chan[String] - out.attach(s => println("get " + s)) - //spawn < Producer(0, in) | Consumer(out) | Spec(in, out) > - spawn < Producer(0, in) | Consumer(out) | Impl(in, out) > - -} |