Class: Omnizip::Formats::Cpio::Writer

Inherits:
Object
  • Object
show all
Includes:
Constants
Defined in:
lib/omnizip/formats/cpio/writer.rb

Overview

CPIO archive writer

Creates CPIO archives in newc, CRC, or ODC format. Ported from libarchive's archive_write_set_format_cpio_newc.c

Examples:

Create CPIO archive

writer = Cpio::Writer.new('archive.cpio')
writer.add_file('file.txt')
writer.add_directory('dir/')
writer.write

With CRC format

writer = Cpio::Writer.new('archive.cpio', format: :crc)
writer.add_directory('initramfs/')
writer.write

Constant Summary

Constants included from Constants

Constants::MAGIC_BINARY, Constants::MAGIC_CRC, Constants::MAGIC_NEWC, Constants::MAGIC_ODC, Constants::NEWC_ALIGNMENT, Constants::NEWC_HEADER_SIZE, Constants::S_IFBLK, Constants::S_IFCHR, Constants::S_IFDIR, Constants::S_IFIFO, Constants::S_IFLNK, Constants::S_IFMT, Constants::S_IFREG, Constants::S_IFSOCK, Constants::S_IRGRP, Constants::S_IROTH, Constants::S_IRUSR, Constants::S_IRWXG, Constants::S_IRWXO, Constants::S_IRWXU, Constants::S_ISGID, Constants::S_ISUID, Constants::S_ISVTX, Constants::S_IWGRP, Constants::S_IWOTH, Constants::S_IWUSR, Constants::S_IXGRP, Constants::S_IXOTH, Constants::S_IXUSR, Constants::TRAILER_NAME

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(output_path, format: :newc) ⇒ Writer

Initialize CPIO writer

Parameters:

  • output_path (String) —

    Output CPIO file path

  • format (Symbol) (defaults to: :newc) —

    CPIO format (:newc, :crc, :odc)



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# File 'lib/omnizip/formats/cpio/writer.rb', line 39

def initialize(output_path, format: :newc)
  @output_path = output_path
  @format = validate_format(format)
  @entries = []
  @inode_counter = 1
end

Instance Attribute Details

#entries ⇒ Array<Entry> (readonly)

Returns Entries to write.

Returns:

  • (Array<Entry>) —

    Entries to write



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# File 'lib/omnizip/formats/cpio/writer.rb', line 33

def entries
  @entries
end

#format ⇒ Symbol (readonly)

Returns CPIO format (:newc, :crc, :odc).

Returns:

  • (Symbol) —

    CPIO format (:newc, :crc, :odc)



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# File 'lib/omnizip/formats/cpio/writer.rb', line 30

def format
  @format
end

#output_path ⇒ String (readonly)

Returns Output archive path.

Returns:

  • (String) —

    Output archive path



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# File 'lib/omnizip/formats/cpio/writer.rb', line 27

def output_path
  @output_path
end

Instance Method Details

#add_directory(dir_path, recursive: true, cpio_path: nil) ⇒ Object

Add directory to archive

Parameters:

  • dir_path (String) —

    Source directory path

  • recursive (Boolean) (defaults to: true) —

    Include subdirectories

  • cpio_path (String, nil) (defaults to: nil) —

    Path in archive

Raises:

  • (ArgumentError) —

    if directory doesn't exist



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# File 'lib/omnizip/formats/cpio/writer.rb', line 83

def add_directory(dir_path, recursive: true, cpio_path: nil)
  raise ArgumentError, "Directory not found: #{dir_path}" unless
    Dir.exist?(dir_path)

  # Default to basename if no cpio_path specified
  cpio_path = File.basename(dir_path) if cpio_path.nil?
  # Normalize path: remove leading slashes to make relative
  cpio_path = cpio_path.sub(%r{^/+}, "")
  stat = File.lstat(dir_path)

  # Add directory entry
  entry = create_entry_from_stat(cpio_path, stat, "")
  @entries << entry
  @inode_counter += 1

  # Add contents if recursive
  if recursive
    Dir.foreach(dir_path) do |item|
      next if [".", ".."].include?(item)

      item_path = File.join(dir_path, item)
      item_cpio_path = "#{cpio_path}/#{item}"

      if File.directory?(item_path)
        add_directory(item_path, recursive: true,
                                 cpio_path: item_cpio_path)
      else
        add_file(item_path, item_cpio_path)
      end
    end
  end
end

#add_file(file_path, cpio_path = nil) ⇒ Object

Add file to archive

Parameters:

  • file_path (String) —

    Source file path

  • cpio_path (String, nil) (defaults to: nil) —

    Path in archive (defaults to file_path)

Raises:

  • (ArgumentError) —

    if file doesn't exist



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# File 'lib/omnizip/formats/cpio/writer.rb', line 51

def add_file(file_path, cpio_path = nil)
  raise ArgumentError, "File not found: #{file_path}" unless
    File.exist?(file_path) || File.symlink?(file_path)

  # Default to basename if no cpio_path specified
  cpio_path = File.basename(file_path) if cpio_path.nil?
  # Use lstat to not follow symlinks
  stat = File.lstat(file_path)

  # Normalize path: remove leading slashes to make relative
  cpio_path = cpio_path.sub(%r{^/+}, "")

  # Read file data unless it's a symlink
  data = if File.symlink?(file_path)
           File.readlink(file_path)
         elsif stat.file?
           File.binread(file_path)
         else
           ""
         end

  entry = create_entry_from_stat(cpio_path, stat, data)
  @entries << entry
  @inode_counter += 1
end

#write ⇒ Object

Write CPIO archive

Raises:



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# File 'lib/omnizip/formats/cpio/writer.rb', line 119

def write
  File.open(@output_path, "wb") do |io|
    # Write all entries
    @entries.each do |entry|
      write_entry(io, entry)
    end

    # Write trailer
    write_trailer(io)
  end

  @output_path
end