Class: Omnizip::Algorithms::LZMA2::LZMA2Chunk

Inherits:
Object
  • Object
show all
Defined in:
lib/omnizip/algorithms/lzma2/lzma2_chunk.rb

Overview

LZMA2 Chunk structure using Array#pack for binary serialization

Constant Summary collapse

TYPE_END = 
:end
TYPE_UNCOMPRESSED = 
:uncompressed
TYPE_COMPRESSED = 
:compressed

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(chunk_type:, need_dict_reset:, need_state_reset:, need_props:, uncompressed_data: "", compressed_data: "", properties: nil, compressed_size: nil) ⇒ LZMA2Chunk

Returns a new instance of LZMA2Chunk.



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 27

def initialize(chunk_type:, need_dict_reset:, need_state_reset:,
               need_props:, uncompressed_data: "",
               compressed_data: "", properties: nil,
               compressed_size: nil)
  # Validate chunk_type
  valid_types = [TYPE_END, TYPE_UNCOMPRESSED, TYPE_COMPRESSED]
  unless valid_types.include?(chunk_type)
    raise ArgumentError,
          "Invalid chunk_type: #{chunk_type.inspect}. " \
          "Must be :end, :uncompressed, or :compressed"
  end

  @chunk_type = chunk_type
  @uncompressed_data = uncompressed_data
  @compressed_data = compressed_data
  # For XZ format, compressed_size excludes flush bytes
  # For standalone LZMA2, compressed_size includes all bytes
  @compressed_size = compressed_size || @compressed_data.bytesize
  @properties = properties
  @need_dict_reset = need_dict_reset
  @need_state_reset = need_state_reset
  @need_props = need_props

  @control_byte = build_control_byte if chunk_type != TYPE_END
end

Instance Attribute Details

#chunk_type ⇒ Object (readonly)

Returns the value of attribute chunk_type.



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 12

def chunk_type
  @chunk_type
end

#compressed_data ⇒ Object (readonly)

Returns the value of attribute compressed_data.



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 12

def compressed_data
  @compressed_data
end

#control_byte ⇒ Object (readonly)

Returns the value of attribute control_byte.



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 12

def control_byte
  @control_byte
end

#properties ⇒ Object (readonly)

Returns the value of attribute properties.



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 12

def properties
  @properties
end

#uncompressed_data ⇒ Object (readonly)

Returns the value of attribute uncompressed_data.



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 12

def uncompressed_data
  @uncompressed_data
end

Class Method Details

.end_chunk ⇒ Object

Factory method for end marker



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 16

def self.end_chunk
  new(
    chunk_type: TYPE_END,
    uncompressed_data: "",
    compressed_data: "",
    need_dict_reset: false,
    need_state_reset: false,
    need_props: false,
  )
end

Instance Method Details

#to_bytes ⇒ Object

Serialize to binary format



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# File 'lib/omnizip/algorithms/lzma2/lzma2_chunk.rb', line 54

def to_bytes
  case @chunk_type
  when TYPE_END
    [0x00].pack("C")
  when TYPE_UNCOMPRESSED
    serialize_uncompressed
  when TYPE_COMPRESSED
    serialize_compressed
  end
end