Module: BinData::IO::UnSeekableIO

Defined in:
lib/bindata/io.rb

Overview

A module to be prepended to RawIO or Transform when the data stream is not seekable. This is either due to underlying stream being unseekable or the transform changes the number of bytes.

Instance Method Summary collapse

Instance Method Details

#num_bytes_remaining ⇒ Object

Raises:

  • (IOError) 


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# File 'lib/bindata/io.rb', line 499

def num_bytes_remaining
  raise IOError, "stream is unseekable"
end

#seek_abs(n) ⇒ Object 



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# File 'lib/bindata/io.rb', line 514

def seek_abs(n)
  skip(n - offset)
end

#seekable? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/bindata/io.rb', line 495

def seekable?
  false
end

#skip(n) ⇒ Object

Raises:

  • (IOError) 


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# File 'lib/bindata/io.rb', line 503

def skip(n)
  raise IOError, "can not skip backwards" if n.negative?

  # skip over data in 8k blocks
  while n > 0
    bytes_to_read = [n, 8192].min
    read(bytes_to_read)
    n -= bytes_to_read
  end
end