80 lines
1.4 KiB
Go
80 lines
1.4 KiB
Go
/*
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* ewd123a.go
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*
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* A program to represent the first mutex strategy, as described in EWD123.
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*
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* Copyright (c) 2019-2019 HS Emden/Leer
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* All Rights Reserved.
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*
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* version 1.00 - 21 Oct 2019 - GJV - initial version
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*
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* author: Gert Veltink, gert.veltink@hs-emden-leer.de (GJV)
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*/
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package ewd123a
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import (
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"../controller"
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"log"
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)
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// global synchronization variable
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var turn = 1
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// Start starts the execution of EWD123a.
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func Start() {
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go process1()
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go process2()
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}
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// process1 simulates the behaviour of the first process
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func process1() {
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L1:
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//wait till turn = 2 (program can run)
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if turn == 2 {
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//log.Printf("Process 1 waiting\n")
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goto L1
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}
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controller.EnterCriticalSection(1)
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controller.InsideCriticalSection(1, 50)
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controller.LeaveCriticalSection(1)
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turn = 2
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//Process 2 can run now (and will in some cases)
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controller.OutsideCriticalSection(1, 100)
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if controller.ProcessCrashed(0.01) {
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log.Printf("Process 1 crashed\n")
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return
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}
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goto L1
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}
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// process2 simulates the behaviour of the second process
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func process2() {
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L2:
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if turn == 1 {
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//log.Printf("Process 2 waiting\n")
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goto L2
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}
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controller.EnterCriticalSection(2)
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controller.InsideCriticalSection(2, 50)
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controller.LeaveCriticalSection(2)
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turn = 1
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//Process can run now (and will in some cases)
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controller.OutsideCriticalSection(2, 100)
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if controller.ProcessCrashed(0.01) {
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log.Printf("Process 2 crashed\n")
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return
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}
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goto L2
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}
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