Class: Bitindex::Reader

Inherits:
Object
  • Object
show all
Includes:
Common
Defined in:
lib/bitindex/reader.rb

Constant Summary

Constants included from Common

Common::SIGNED_16BIT, Common::SIGNED_32BIT, Common::UNSIGNED_16BIT, Common::UNSIGNED_32BIT

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Common

#bit_set?, #build_mask, #byte_pos, #set_bit, #unset_bit

Constructor Details

#initialize(filepath, opts = {}) ⇒ Reader

Returns a new instance of Reader.



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# File 'lib/bitindex/reader.rb', line 8

def initialize filepath, opts = {}

  raise "#{ filepath } is not readable" unless filepath and File.readable?(filepath)
  @filepath = filepath

  @ltor = !(opts[:ltor] == false)
end

Instance Attribute Details

#filepath ⇒ Object (readonly)

Returns the value of attribute filepath.



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# File 'lib/bitindex/reader.rb', line 5

def filepath
  @filepath
end

#ltor ⇒ Object

Returns the value of attribute ltor.



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# File 'lib/bitindex/reader.rb', line 6

def ltor
  @ltor
end

Instance Method Details

#all_set(array) ⇒ Object 



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# File 'lib/bitindex/reader.rb', line 30

def all_set array
  arr = []
  File.open(self.filepath, 'rb') do |io|
    cur_idx = nil
    cur_byte = nil
    array.each do |n|
      idx = byte_pos n
      if idx < io.size
        if cur_idx.nil? or cur_idx < idx
          io.seek idx, IO::SEEK_SET
          cur_byte = io.getbyte
        end
        arr << n if bit_set? cur_byte, n, self.ltor
      end
    end
  end
  arr
end

#set?(value) ⇒ Boolean Also known as: is_set?

Returns:

  • (Boolean) 


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# File 'lib/bitindex/reader.rb', line 16

def set? value
  result = false
  File.open(self.filepath, 'rb') do |io|
    idx = byte_pos value
    if idx < io.size
      io.seek idx, IO::SEEK_SET
      result = bit_set? io.getbyte, value, self.ltor
    end
  end
  result
end