Module: SJCL::Codec::Base64

Defined in:
lib/sjcl/codec_base64.rb

Constant Summary collapse

CHARS = 
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

Class Method Summary collapse

Class Method Details

.fromBits(arr, noEquals = false, url = false) ⇒ Object 



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# File 'lib/sjcl/codec_base64.rb', line 4

def self.fromBits(arr, noEquals=false, url=false)
  out = ""
  bits=0
  c = CHARS.dup
  ta=0
  i = 0
  bl = SJCL::BitArray.bitLength(arr)
  if (url)
    c = c[0,62] + '-_';
  end
  while (out.length * 6) < bl
    a = (arr[i] & 0xFFFFFFFF) || 0
    out += c[(ta ^ a >> bits) >> 26,1]
    if (bits < 6)
      ta = (a << (6-bits)) & 0xFFFFFFFF
      bits += 26
      i += 1
    else
      ta = (ta <<  6) & 0xFFFFFFFF
      bits -= 6
    end
  end
  while ((out.length & 3 > 0) && !noEquals)
    out += "="
  end
  return out
end

.toBits(str, url = false) ⇒ Object 



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# File 'lib/sjcl/codec_base64.rb', line 32

def self.toBits(str, url=false)
  i=0
  bits = 0
  ta = 0
  c = CHARS.dup
  out = []
  if (url)
    c = c[0,62] + '-_'
  end
  while (i < str.length)
    str = str.gsub(/\s|=/, '')
    x = c.index(str[i]);
    unless x
      raise "this isn't base64!"
    end
    if (bits > 26)
      bits -= 26;
      out << ((ta ^ x >> bits) & 0xFFFFFFFF)
      ta  = x << (32-bits)
      ta &= 0xFFFFFFFF
    else
      bits += 6
      ta ^= x << (32-bits)
      ta &= 0xFFFFFFFF
    end
    i += 1
  end
  if (bits&56 > 0)
    out.push(SJCL::BitArray.partial(bits & 56, ta, 1));
  end
  return out
end