72 lines
1.6 KiB
C#
72 lines
1.6 KiB
C#
using System;
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using System.Threading;
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namespace org.budnhead
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{
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/**
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* ConsumerProducerLock
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*
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* Lock a Resource for one producer, mutliple consumers (read-only)
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*
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* Producer Lock: Producer will receive and hold lock if no other producer is active
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* Producer Exclusive Lock: Producer will receive and hold lock, while no consumers are active
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* Consumer Lock: Consumers will get lock while no Producer Exclusive Lock is held
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*
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**/
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public class ConsumerProducerLock
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{
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Object producer;
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Object producerExclusiveLock;
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Object consumerLock;
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Int32 consumers;
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bool producerIsExclusive;
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public ConsumerProducerLock(){
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producer = new object();
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producerExclusiveLock = new object();
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consumerLock = new object();
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consumers = 0;
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}
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public void ConsumerEnter(){
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Monitor.Enter(producerExclusiveLock);
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Monitor.Enter(consumerLock);
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consumers ++;
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Monitor.Exit(consumerLock);
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Monitor.Exit(producerExclusiveLock);
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}
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public void ConsumerExit(){
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Monitor.Enter(producerExclusiveLock);
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Monitor.Enter(consumerLock);
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consumers --;
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if (consumers == 0){
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Monitor.Pulse(producerExclusiveLock);
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}
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Monitor.Exit(consumerLock);
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Monitor.Exit(producerExclusiveLock);
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}
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public void ProducerEnter(){
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Monitor.Enter(producer);
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}
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public void ProducerExit(){
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Monitor.Exit(producer);
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if (Monitor.IsEntered(producerExclusiveLock)){
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Monitor.Exit(producerExclusiveLock);
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}
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}
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public void producerExclusive(){
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Monitor.Enter(producerExclusiveLock);
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if (consumers > 0){
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Monitor.Wait(producerExclusiveLock);
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}
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}
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}
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}
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