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Source Code

# File sync.rb, line 140
def sync_lock(m = EX)
  return unlock if m == UN

  until (Thread.critical = true; sync_try_lock_sub(m))
    if sync_sh_locker[Thread.current]
      sync_upgrade_waiting.push [Thread.current, sync_sh_locker[Thread.current]]
      sync_sh_locker.delete(Thread.current)
    else
      sync_waiting.push Thread.current
    end
    Thread.stop
  end
  Thread.critical = false
  self
end