Class: Omnizip::Formats::Rar::Rar5::MultiVolume::VolumeWriter

Inherits:
Object
  • Object
show all
Defined in:
lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb

Overview

Volume writer for multi-volume archives

This class writes individual .rar volume files with proper RAR5 headers and volume-specific flags.

Examples:

Write a volume

writer = VolumeWriter.new('archive.part1.rar', volume_number: 1, is_last: false)
writer.write_signature
writer.write_main_header
writer.write_file_data(file_header, compressed_data)
writer.write_end_header
writer.close

Constant Summary collapse

VOLUME_ARCHIVE_FLAG =

Main header flags for volume archives NOTE: Bits 0-1 are reserved for common flags (EXTRA_AREA, DATA_AREA) Use bits 2+ for format-specific flags

0x0004
VOLUME_NUMBER_FLAG =

Bit 2: This is a volume archive

0x0008
VOLUME_END_FLAG =

End header flags

0x0001

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(path, volume_number:, is_last: false) ⇒ VolumeWriter

Initialize volume writer

Parameters:

  • path (String)

    Output volume file path

  • volume_number (Integer)

    Volume number (1-based)

  • is_last (Boolean) (defaults to: false)

    Is this the last volume?



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 47

def initialize(path, volume_number:, is_last: false)
  @path = path
  @volume_number = volume_number
  @is_last = is_last
  @io = nil
end

Instance Attribute Details

#ioIO (readonly)

Returns File handle.

Returns:

  • (IO)

    File handle



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 40

def io
  @io
end

#is_lastBoolean (readonly)

Returns Is this the last volume?.

Returns:

  • (Boolean)

    Is this the last volume?



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 37

def is_last
  @is_last
end

#pathString (readonly)

Returns Volume file path.

Returns:

  • (String)

    Volume file path



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 31

def path
  @path
end

#volume_numberInteger (readonly)

Returns Volume number (1-based).

Returns:

  • (Integer)

    Volume number (1-based)



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 34

def volume_number
  @volume_number
end

Class Method Details

.volume_filename(base_path, volume_number, naming: "part") ⇒ String

Generate volume filename from base name

Parameters:

  • base_path (String)

    Base archive path (e.g., "archive.rar")

  • volume_number (Integer)

    Volume number (1-based)

  • naming (String) (defaults to: "part")

    Naming pattern ("part" or "volume")

Returns:

  • (String)

    Volume filename (e.g., "archive.part1.rar")



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 158

def self.volume_filename(base_path, volume_number, naming: "part")
  dir = File.dirname(base_path)
  basename = File.basename(base_path, ".*")
  ext = File.extname(base_path)

  volume_name = case naming
                when "part"
                  "#{basename}.part#{volume_number}#{ext}"
                when "volume"
                  "#{basename}.vol#{volume_number}#{ext}"
                when "numeric"
                  # Simple numeric suffix: archive.rar, archive.r00, archive.r01, etc.
                  if volume_number == 1
                    "#{basename}#{ext}"
                  else
                    # Volume 2 => r00, Volume 3 => r01, etc.
                    "#{basename}.r#{format('%02d',
                                           volume_number - 2)}"
                  end
                else
                  "#{basename}.part#{volume_number}#{ext}"
                end

  # Handle relative vs absolute paths
  if dir == "."
    volume_name
  else
    File.join(dir, volume_name)
  end
end

Instance Method Details

#closevoid

This method returns an undefined value.

Close volume file



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 64

def close
  @io&.close
  @io = nil
end

#openvoid

This method returns an undefined value.

Open volume file for writing



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 57

def open
  @io = File.open(@path, "wb")
end

#write {|writer| ... } ⇒ void

This method returns an undefined value.

Write with automatic open/close

Yields:

  • (writer)

    Yields self for writing operations



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 73

def write
  open
  yield self
ensure
  close
end

#write_end_headervoid

This method returns an undefined value.

Write End header with volume flags



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 135

def write_end_header
  raise "Volume not open" unless @io

  # Set END_OF_ARCHIVE flags
  flags = 0
  flags | VOLUME_END_FLAG unless @is_last

  # EndHeader always encodes the plain END_OF_ARCHIVE
  # marker: the RAR5 spec makes the volume flag optional,
  # readers position the marker inside the volume
  # sequence, and the omnizip-rs reference (read-side)
  # carries no writer-side volume-flag encoding to port.
  header = EndHeader.new

  @io.write(header.encode)
end

#write_file_data(file_header, compressed_data) ⇒ void

This method returns an undefined value.

Write file data (header + compressed data)

Parameters:

  • file_header (FileHeader)

    File header

  • compressed_data (String)

    Compressed file data



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 125

def write_file_data(file_header, compressed_data)
  raise "Volume not open" unless @io

  @io.write(file_header.encode)
  @io.write(compressed_data)
end

#write_main_headervoid

This method returns an undefined value.

Write Main header with volume flags



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 95

def write_main_header
  raise "Volume not open" unless @io

  # Set volume-specific flags
  flags = VOLUME_ARCHIVE_FLAG

  # Add volume number in extra area for volumes 2+
  nil
  if @volume_number > 1
    flags |= VOLUME_NUMBER_FLAG
    # Volume number as VINT in extra area
    VINT.encode(@volume_number).pack("C*")
  end

  header = MainHeader.new(flags: flags)

  # Extra areas are not written: MainHeader does not
  # model them and the omnizip-rs reference implements
  # RAR5 reading only, so there is no writer-side spec
  # to port. Volumes work without extras (the field is
  # optional).

  @io.write(header.encode)
end

#write_signaturevoid

This method returns an undefined value.

Write RAR5 signature



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# File 'lib/omnizip/formats/rar/rar5/multi_volume/volume_writer.rb', line 83

def write_signature
  raise "Volume not open" unless @io

  # RAR5 signature: "Rar!\x1A\x07\x01\x00"
  signature = [0x52, 0x61, 0x72, 0x21, 0x1A, 0x07, 0x01,
               0x00].pack("C*")
  @io.write(signature)
end