Class: FastCache::CRC32

Inherits:
Object
  • Object
show all
Defined in:
lib/fastcache/hash/crc32.rb

Instance Method Summary collapse

Constructor Details

#initialize(string = nil) ⇒ CRC32

Returns a new instance of CRC32.



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# File 'lib/fastcache/hash/crc32.rb', line 3

def initialize(string = nil)
  @crc = 0xFFFFFFFF
  self << string if string
end

Instance Method Details

#<<(string) ⇒ Object 



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# File 'lib/fastcache/hash/crc32.rb', line 8

def <<(string)
  string.size.times do |i|
    @crc ^= string[i]
    8.times do
      if (@crc & 1).zero?
        @crc >>= 1
      else
        @crc = (@crc >> 1) ^ 0xEDB88320
      end
    end
  end
  self
end

#digest ⇒ Object 



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# File 'lib/fastcache/hash/crc32.rb', line 22

def digest
  [@crc ^ 0xFFFFFFFF].pack('N')
end

#hexdigest ⇒ Object 



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# File 'lib/fastcache/hash/crc32.rb', line 26

def hexdigest
  (@crc ^ 0xFFFFFFFF).to_s(16)
end