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# -*- coding: binary -*-
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module Rex
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###
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#
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# This class contains zero or more abstract jobs that can be enumerated and
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# stopped in a generic fashion.  This is used to provide a mechanism for
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# keeping track of arbitrary contexts that may or may not require a dedicated
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# thread.
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#
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###
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class JobContainer < Hash
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  def initialize
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    self.job_id_pool = 0
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  end
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  #
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  # Adds an already running task as a symbolic job to the container.
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  #
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  def add_job(name, ctx, run_proc, clean_proc)
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    real_name = name
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    count     = 0
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    jid       = job_id_pool
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    self.job_id_pool += 1
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    # If we were not supplied with a job name, pick one from the hat
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    if (real_name == nil)
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      real_name = '#' + jid.to_s
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    end
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    # Find a unique job name
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    while (j = self[real_name])
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      real_name  = name + " #{count}"
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      count     += 1
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    end
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    j = Job.new(self, jid, real_name, ctx, run_proc, clean_proc)
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    self[jid.to_s] = j
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  end
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  #
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  # Starts a job using the supplied name and run/clean procedures.
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  #
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  def start_job(name, ctx, run_proc, clean_proc = nil)
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    j = add_job(name, ctx, run_proc, clean_proc)
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    j.start
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    j.jid
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  end
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  #
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  # Starts a background job that doesn't call the cleanup routine or run
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  # the run_proc in its own thread.  Rather, the run_proc is called
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  # immediately and the clean_proc is never called until the job is removed
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  # from the job container.
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  #
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  def start_bg_job(name, ctx, run_proc, clean_proc = nil, async = true)
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    j = add_job(name, ctx, run_proc, clean_proc)
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    j.start(async)
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    j.jid
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  end
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  #
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  # Stops the job with the supplied name and forces it to cleanup.  Stopping
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  # the job also leads to its removal.
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  #
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  def stop_job(jid)
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    if (j = self[jid.to_s])
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      j.stop
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      remove_job(j)
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    end
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  end
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  #
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  # Removes a job that was previously running.  This is typically called when
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  # a job completes its task.
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  #
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  def remove_job(inst)
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    self.delete(inst.jid.to_s)
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  end
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  #
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  # Overrides the builtin 'each' operator to avoid the following exception on Ruby 1.9.2+
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  #    "can't add a new key into hash during iteration"
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  #
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  def each(&block)
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    list = []
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    self.keys.sort.each do |sidx|
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      list << [sidx, self[sidx]]
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    end
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    list.each(&block)
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  end
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protected
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  attr_accessor :job_id_pool # :nodoc:
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end
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end
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