FfiWideChar

A Ruby gem helper for FFI binding libraries to convert from/to C native wchar_t wide-string.

It provides 2 methods: read_wide_string and to_wide_string for converting.

Add this line to your application's Gemfile:

gem 'ffi_wide_char'

And then execute:

$ bundle

Or install it yourself as:

$ gem install ffi_wide_char

Example of calling native library functions using wide-string type:

require 'ffi_wide_char'

# Unicode Popup Dialog
module Win
  extend FFI::Library

  ffi_lib 'user32'
  ffi_convention :stdcall

  attach_function :message_box, :MessageBoxW, %i[pointer buffer_in buffer_in int], :int
end

msg = FfiWideChar.to_wide_string('a中Я')
Win.message_box(nil, msg, msg, 0)

# Convert multibyte to wide-string
ptr = FFI::MemoryPointer.new(:char, 16)
FfiWideChar::LibC.mbstowcs(ptr, '©Ðõ'.encode('filesystem'), 4)

str = FfiWideChar.read_wide_string ptr
puts str.encode('UTF-8')

After checking out the repo, run bundle install to install dependencies. Then, run bundle exec rake to run the tests. You can also run irb -r bundler/setup -r ffi_wide_char for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install.

Bug reports and pull requests are welcome on GitHub at https://github.com/nthachus/ffi_wide_char.

The gem is available as open source under the terms of the MIT License.