info.cr

module Sys::Info
  VERSION = "0.1.0"

  lib C
    struct Uname
      sysname : StaticArray(UInt8, 256)
      nodename : StaticArray(UInt8, 256)
      release : StaticArray(UInt8, 256)
      version : StaticArray(UInt8, 256)
      machine : StaticArray(UInt8, 256)
    end

    fun uname(value : Uname*) : Int32
  end

  struct Uname
    getter cstruct

    macro get(prop)
      def {{prop}}
        String.build do |io|
          cstruct.{{prop}}.each do |n|
            io.write_byte n.to_u8
          end
        end
      end
    end

    def initialize(@cstruct : C::Uname)
    end

    get sysname
    get nodename
    get release
    get version
    get machine
  end

  def self.uname
    uname_struct = C::Uname.new

    if C.uname(pointerof(uname_struct)) < 0
      raise "uname function call failed"
    else
      Uname.new(uname_struct)
    end
  end
end

uname = Sys::Info.uname

puts uname.sysname
puts uname.nodename
puts uname.release
puts uname.version
puts uname.machine