# Fact: physicalprocessorcount
#
# Purpose: Return the number of physical processors.
#
# Resolution:
#
#   Attempts to use sysfs to get the physical IDs of the processors. Falls
#   back to /proc/cpuinfo and "physical id" if sysfs is not available.
#
# Caveats:
#

if ["Linux", "GNU/kFreeBSD"].include? Facter.value(:kernel)
  Facter.add('physicalprocessorcount') do
    confine :kernel => :linux

    setcode do
      sysfs_cpu_directory = '/sys/devices/system/cpu' # This should always be there ...

      if File.exists?(sysfs_cpu_directory)
        #
        # We assume that the sysfs file system has the correct number of entries
        # under the "/sys/device/system/cpu" directory and if so then we process
        # content of the file "physical_package_id" located inside the "topology"
        # directory in each of the per-CPU sub-directories.
        #
        # As per Linux Kernel documentation and the file "cputopology.txt" located
        # inside the "/usr/src/linux/Documentation" directory we can find following
        # short explanation:
        #
        # (...)
        #
        # 1) /sys/devices/system/cpu/cpuX/topology/physical_package_id:
        #
        #         physical package id of cpuX. Typically corresponds to a physical
        #         socket number, but the actual value is architecture and platform
        #         dependent.
        #
        # (...)
        #
        lookup_pattern = "#{sysfs_cpu_directory}" +
          "/cpu*/topology/physical_package_id"

        Dir.glob(lookup_pattern).collect { |f| Facter::Util::Resolution.exec("cat #{f}")}.uniq.size

      else
        #
        # Try to count number of CPUs using the proc file system next ...
        #
        # We assume that /proc/cpuinfo has what we need and is so then we need
        # to make sure that we only count unique entries ...
        #
        str = Facter::Util::Resolution.exec("grep 'physical.\\+:' /proc/cpuinfo")

        if str then str.scan(/\d+/).uniq.size; end
      end
    end
  end
end

if Facter.value(:kernel) == "OpenBSD"
    Facter.add('physicalprocessorcount') do
        confine :kernel => :openbsd
        setcode do
            Facter::Util::Resolution.exec("sysctl -n hw.ncpufound")
        end
    end
end
