55 lines
1.1 KiB
Ruby
55 lines
1.1 KiB
Ruby
# frozen_string_literal: true
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class FinalDestination::Resolver
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@mutex = Mutex.new
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def self.lookup(addr, timeout: nil)
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timeout ||= 2
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@mutex.synchronize do
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@result = nil
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@queue ||= Queue.new
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@queue << ""
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ensure_lookup_thread
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@lookup = addr
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@parent = Thread.current
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# This sleep will be interrupted by the lookup thread
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# if completed within timeout
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sleep timeout
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if !@result
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@thread.kill
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@thread.join
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@thread = nil
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if @error
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@error.backtrace.push(*caller)
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raise @error
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else
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raise Timeout::Error
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end
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end
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@result
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end
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end
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private
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def self.ensure_lookup_thread
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return if @thread&.alive?
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@thread = Thread.new do
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while true
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@queue.deq
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@error = nil
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begin
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@result = Addrinfo.getaddrinfo(@lookup, 80, nil, :STREAM).map(&:ip_address)
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rescue => e
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@error = e
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end
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@parent.wakeup
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end
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end
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@thread.name = "final-destination_resolver_thread"
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end
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end
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