Handling Corrupted Archives

Detecting Corruption

Signs of corruption:

  • Invalid signature errors

  • Checksum mismatches

  • Unexpected end of file

  • Decompression failures

Using Salvage Mode 

# Enable salvage mode to recover what's possible
extractor = Cabriolet::CAB::Extractor.new(
  salvage_mode: true,
  skip_checksum: true,
  continue_on_error: true
)

begin
  cabinet = extractor.parse('corrupted.cab')

  recovered = 0
  failed = 0

  cabinet.files.each do |file|
    begin
      File.write("recovered/#{file.name}", file.data, mode: 'wb')
      recovered += 1
      puts "✓ #{file.name}"
    rescue => e
      failed += 1
      puts "✗ #{file.name}: #{e.message}"
    end
  end

  puts "\nRecovered: #{recovered}, Failed: #{failed}"
rescue => e
  puts "Partial recovery: #{e.message}"
end

Partial Recovery Strategies

  1. Extract file by file::

    cab.files.each do |file|
  begin
    data = file.data
    # Save successfully extracted file
  rescue
    # Skip corrupted file, continue with next
  end
end

  2. Skip checksum validation::

    cab = Cabriolet::CAB::Parser.new(
  skip_checksum: true
).parse('file.cab')

  3. Use external tools::

    • Microsoft expand.exe (Windows)

    • cabextract (Linux/macOS)

    • Compare results with Cabriolet

Prevention

  1. Verify after creation::

    # Test archive after creation
cab = Cabriolet::CAB::Parser.new.parse('archive.cab')
cab.files.each { |f| f.data }  # Trigger decompression

  2. Use checksums::

    # Generate archive checksum
checksum = Digest::SHA256.file('archive.cab').hexdigest
File.write('archive.cab.sha256', checksum)

  3. Store redundant copies

  4. Use error-correcting storage (RAID, cloud with redundancy)

See also