Class: Archive::Zip::Codec::TraditionalEncryption::Reader

Inherits:
Base
  • Object
show all
Defined in:
lib/archive/zip/codec/traditional_encryption/reader.rb

Overview

Archive::Zip::Codec::TraditionalEncryption#decompressor method.

Instance Method Summary collapse

Methods inherited from Base

#initialize, #seek

Constructor Details

This class inherits a constructor from Archive::Zip::Codec::TraditionalEncryption::Base

Instance Method Details

#read(length, buffer: nil, buffer_offset: 0) ⇒ Object

Reads, decrypts, and returns at most length bytes from the delegate IO object.

Raises EOFError if there is no data to read.



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# File 'lib/archive/zip/codec/traditional_encryption/reader.rb', line 19

def read(length, buffer: nil, buffer_offset: 0)
  # This short circuits if the header has already been read.
  result = read_header
  return result if Symbol === result

  result = super
  return result if Symbol === result

  if buffer.nil?
    buffer = result
    buffer_offset = 0
    length = buffer.bytesize
  else
    length = result
  end

  buffer[buffer_offset, length].to_enum(:each_byte).each_with_index do |byte, idx|
    buffer[idx] = (byte ^ decrypt_byte).chr
    update_keys(buffer[idx])
  end
  @bytes_processed += length

  result
end