54 lines
758 B
Ruby
54 lines
758 B
Ruby
#
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# The Dining Philosophers - thread example
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#
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srand
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#srand
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N=9 # number of philosophers
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$forks = []
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for i in 0..N-1
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$forks[i] = Thread::Mutex.new
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end
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$state = "-o"*N
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def wait
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sleep rand(20)/10.0
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end
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def think(n)
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wait
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end
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def eat(n)
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wait
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end
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def philosopher(n)
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while true
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think n
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$forks[n].lock
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if not $forks[(n+1)%N].try_lock
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$forks[n].unlock # avoid deadlock
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next
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end
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$state[n*2] = ?|;
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$state[(n+1)%N*2] = ?|;
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$state[n*2+1] = ?*;
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print $state, "\n"
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eat(n)
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$state[n*2] = ?-;
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$state[(n+1)%N*2] = ?-;
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$state[n*2+1] = ?o;
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print $state, "\n"
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$forks[n].unlock
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$forks[(n+1)%N].unlock
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end
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end
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for n in 0..N-1
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Thread.start(n){|i| philosopher(i)}
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sleep 0.1
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end
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sleep
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