expand zip-files (with pathname encoding conversion) <http://arika.org/2011/06/07/unzip-rb>

unzip.rb

#!/usr/bin/ruby1.9.1
# encoding: UTF-8
=begin
Copyright (c) 2011, akira yamada
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

コマンドライン引数で指定された一つ以上のzipファイルを
カレントディレクトリに展開します。
その際、zipファイル中のファイル名の文字コードを
システムに適したものに変換します。

zipファイル内のトップディレクトリ直下に
二つ以上のファイルやディレクトリを含む場合には
zipファイルのファイル名から拡張子を除いた
ディレクトリを作りその中に展開します。

zipファイル内のトップディレクトリ直下に
一つのファイルまたはディレクトリしかない場合には
ディレクトリを作らず直接展開します。

いずれのケースでもカレントディレクトリに
すでに同名のファイルやディレクトリがあれば、
上書きせずランダムな名前のディレクトリを作成し
その中に展開します。
=end

require 'zipruby'
require 'fileutils'
require 'tmpdir'
require 'optparse'

# 壊れた文字列をremove_entry_secureで削除しようしたときに
# invalid byte sequenceが発生するのを回避する……
class FileUtils::Entry_
  def remove_dir1
    platform_support {
      Dir.rmdir path().chomp('/')
    }
  end
end

def path_conv(orig_path, path_encoding, cand_encodings)
  converted = nil
  path = orig_path.dup
  fallback_enc = nil

  cand_encodings.each do |enc|
    next unless enc

    path.force_encoding(enc)
    if path.valid_encoding?
      fallback_enc ||= enc
      converted = path.encode(path_encoding) rescue nil
      break if converted
    end
  end

  unless converted
    if fallback_enc
      path.force_encoding(fallback_enc)
      converted = path.encode(path_encoding, :undef => :replace)
    end

    unless converted
      path.force_encoding('ASCII-8BIT')
      converted = path
    end
  end

  converted.gsub(/\\/, '/')
end

def term_conv(str, option)
  if str.encoding != Encoding::US_ASCII &&
      str.encoding != Encoding::BINARY
    str.encode(option[:term_encoding], :undef => :replace)
  else
    str.dup
  end
end

def unzip(zip_path, dst_dir, option)
  path_encoding = option[:path_encoding]
  cand_encodings = option[:cand_encodings]
  list_only = option[:mode] != :extract
  verbose = option[:verbose]

  last_encoding = nil
  Zip::Archive.open(zip_path) do |ar|
    ar.each do |zf|
      path = path_conv(zf.name, path_encoding,
                       [last_encoding, *cand_encodings])
      if path.encoding != Encoding::US_ASCII &&
          path.encoding != Encoding::BINARY
        last_encoding = path.encoding
      end
      t_path = term_conv(path, option)

      if list_only
        mtime = zf.mtime.strftime('%Y-%m-%d %H:%M')
        unless verbose
          puts "#{t_path}"
        else
          if zf.directory?
            puts "d #{mtime} #{t_path}"
          else
            puts "f #{mtime} #{t_path} #{zf.size}"
          end
        end

        next
      end

      dst_path = File.expand_path(path, dst_dir)
      unless File.fnmatch(File.join(dst_dir, '*'), dst_path)
        warn "invalid path name: #{t_path} (skipped)"
        next
      end

      if zf.directory?
        FileUtils.mkdir_p(dst_path)
        warn "created: #{t_path}" if verbose

      else
        FileUtils.mkdir_p(File.dirname(dst_path))
        open(dst_path, 'wb') do |o|
          zf.read do |data|
            o.print data
          end
        end
        warn "extracted: #{t_path}" if verbose
      end
      File.utime(zf.mtime, zf.mtime, dst_path)
    end
  end
end


cand_encodings =
  %w(US-ASCII UTF8-MAC UTF-8 Shift_JIS Windows-31J EUC-JP).
  map {|e| Encoding.find(e) }
path_encoding =
  Encoding.find('filesystem') || Encoding::UTF_8
term_encoding =
  Encoding.find('external') || Encoding::UTF_8
option = {
  :mode => :extract,
  :verbose => false,
  :cand_encodings => cand_encodings,
  :path_encoding => path_encoding,
  :term_encoding => term_encoding,
}

ARGV.options do |o|
  o.banner << ' zipfile...'
  o.on
  o.on 'options:'
  o.on('-l', '--list') { option[:mode] = :list }
  o.on('--encodings=enc1,enc2,...', Array,
       "(default: #{option[:cand_encodings].map(&:to_s).join(', ')})") {|encs|
    option[:cand_encodings] = encs.map {|e| Encoding.find(e) }
  }
  o.on('--try-all-encodings') {
    option[:cand_encodings] = Encoding.list - [Encoding::BINARY]
  }
  o.on('--list-encodings') { puts Encoding.list.map(&:to_s).sort; exit }
  o.on('-v', '--verbose') { option[:verbose] = true }
  o.on('-h', '--help') { puts o; exit }
  o.parse!
end

verbose = option[:verbose]
list_only = option[:mode] != :extract
multi_zip = ARGV.size > 1
head = true

ARGV.each do |zip_path|
  conved_zip_path =
    path_conv(zip_path, option[:path_encoding],
              option[:cand_encodings])
  t_zip_path = term_conv(conved_zip_path, option)

  unless File.exist?(zip_path)
    warn "no such file or directory: #{t_zip_path} (ignored)"
    next
  end

  if list_only
    tmpdir = nil
  else
    tmpdir = Dir.mktmpdir(nil, Dir.pwd)
  end

  begin
    if multi_zip
      if list_only
        puts unless head
        puts "#{t_zip_path}:"
      else
        warn '' unless head
        warn "expanding #{t_zip_path}..."
      end
      head = false
    end

    unzip(zip_path, tmpdir, option)
    next if list_only

    entries = Dir.entries(tmpdir).reject {|e| e == '.' || e == '..' }
    if entries.size == 1
      path = entries.first
      if File.exist?(path)
        warn "extracted file in #{File.basename(tmpdir)}"
      else
        FileUtils.mv(File.join(tmpdir, path), '.')
        FileUtils.remove_entry_secure(tmpdir)
        warn "extracted file at #{term_conv(path, option)}" if verbose || multi_zip
      end

    else
      dst_name = File.basename(conved_zip_path)
      dst_name.sub!(/\.zip\z/i, '')
      if File.exist?(dst_name)
        warn "extracted files in #{File.basename(tmpdir)}"
      else
        FileUtils.mv(tmpdir, dst_name)
        warn "extracted files in #{term_conv(dst_name, option)}"
      end
    end

  rescue Exception
    FileUtils.remove_entry_secure(tmpdir) if tmpdir
    raise
  end
end