Class: SafeTimeout::InterruptingChildProcess

Inherits:
Object
  • Object
show all
Defined in:
lib/safe_timeout/interrupting_child_process.rb

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ InterruptingChildProcess

Returns a new instance of InterruptingChildProcess.



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# File 'lib/safe_timeout/interrupting_child_process.rb', line 4

def initialize(options={})
  @expiration = Time.now.to_f + options.fetch(:timeout)
  @on_timeout = options.fetch(:on_timeout)
end

Instance Method Details

#start(&block) ⇒ Object 



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# File 'lib/safe_timeout/interrupting_child_process.rb', line 9

def start(&block)
  Signal.trap("TRAP", &@on_timeout)
  Kernel.fork { wait_for_expiration }
  yield
ensure
  stop rescue nil
end

#stop ⇒ Object 



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# File 'lib/safe_timeout/interrupting_child_process.rb', line 17

def stop
  # Tell that child to stop interrupting!
  Process.kill("HUP", @child_pid)
end

#wait_for_expiration ⇒ Object 



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# File 'lib/safe_timeout/interrupting_child_process.rb', line 22

def wait_for_expiration
  Signal.trap("HUP") { exit 0 }

  # If the parent dies unexpectedly and the child is never told to
  # stop, it becomes an orphan and is given to the init process (1)
  # or worse yet it becomes a zombie with parent 0. In either case,
  # stop interrupting!
  while Process.ppid > 1
    sleep 0.1
    if Time.now.to_f > @expiration
      Process.kill("TRAP", Process.ppid)
      return
    end
  end
end