=begin
__        ___     _ _       _____                ____ __  __
\ \      / / |__ (_) |_ ___|  ___|   _ ___  ___ / ___|  \/  |
 \ \ /\ / /| '_ \| | __/ _ \ |_ | | | / __|/ _ \ |   | |\/| |
  \ V  V / | | | | | ||  __/  _|| |_| \__ \  __/ |___| |  | |
   \_/\_/  |_| |_|_|\__\___|_|   \__,_|___/\___|\____|_|  |_|
                                            Container Manager

Copyright (C) 2015 David Prandzioch <kontakt@davidprandzioch.de>

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
=end

module ResourceManagerAdapter
  # ResourceManager adapter for Linux
  class Linux

    # Initializes the adapter
    #
    # @raise [RuntimeError]
    def initialize
      if $container_type == 'LXC' && File.exists?($lxc_cgroup_mount_path) == false
        raise RuntimeError, 'no cgroup node found'
      end
    end

    # Finds the total amount of cpu cores
    #
    # @return [Integer]
    def total_cpu_cores
      cpu_cores = `nproc`.strip.to_i

      if $?.exitstatus != 0
        raise RuntimeError, 'could not run nproc'
      end

      return cpu_cores
    end

  end
end