Module: BinData::Int

Defined in:
lib/bindata/int.rb

Overview

Defines a number of classes that contain an integer. The integer is defined by endian, signedness and number of bytes.

Class Method Summary collapse

Class Method Details

.class_name(nbits, endian, signed) ⇒ Object



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# File 'lib/bindata/int.rb', line 22

def class_name(nbits, endian, signed)
  endian_str = (endian == :big) ? "be" : "le"
  base = (signed == :signed) ? "Int" : "Uint"

  "#{base}#{nbits}#{endian_str}"
end

.define_class(nbits, endian, signed) ⇒ Object



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# File 'lib/bindata/int.rb', line 9

def define_class(nbits, endian, signed)
  name = class_name(nbits, endian, signed)
  unless BinData.const_defined?(name)
    BinData.module_eval <<-END
      class #{name} < BinData::BasePrimitive
        Int.define_methods(self, #{nbits}, :#{endian}, :#{signed})
      end
    END
  end

  BinData.const_get(name)
end

.define_methods(int_class, nbits, endian, signed) ⇒ Object



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# File 'lib/bindata/int.rb', line 29

def define_methods(int_class, nbits, endian, signed)
  raise "nbits must be divisible by 8" unless (nbits % 8).zero?

  int_class.module_eval <<-END
    def assign(val)
      #{create_clamp_code(nbits, signed)}
      super(val)
    end

    def do_num_bytes
      #{nbits / 8}
    end

    #---------------
    private

    def sensible_default
      0
    end

    def value_to_binary_string(val)
      #{create_clamp_code(nbits, signed)}
      #{create_int2uint_code(nbits) if signed == :signed}
      #{create_to_binary_s_code(nbits, endian)}
    end

    def read_and_return_value(io)
      val = #{create_read_code(nbits, endian)}
      #{create_uint2int_code(nbits) if signed == :signed}
      val
    end
  END
end