Getting an executable's version with Ruby

win32_version.rb

require 'fiddle'
require 'pry'

version_dll = Fiddle.dlopen('version.dll')

filename = 'C:/Tools/teraterm/ttermpro.exe'

get_file_version_info_size = Fiddle::Function.new(
    version_dll['GetFileVersionInfoSize'],
    [Fiddle::TYPE_VOIDP, Fiddle::TYPE_VOIDP],
    Fiddle::TYPE_LONG
)


s = ''
vsize = get_file_version_info_size.call(filename, s)
puts [vsize, vsize.class]

buffer = "\x00" * vsize

get_file_version_info = Fiddle::Function.new(
    version_dll['GetFileVersionInfo'],
    [Fiddle::TYPE_VOIDP, Fiddle::TYPE_LONG, Fiddle::TYPE_LONG, Fiddle::TYPE_VOIDP],
    Fiddle::TYPE_INT
)

result = get_file_version_info.call(filename, 0, vsize, buffer)

if !result.zero?
    puts buffer
end

ver_query_value = Fiddle::Function.new(
    version_dll['VerQueryValue'],
    [Fiddle::TYPE_VOIDP, Fiddle::TYPE_VOIDP, Fiddle::TYPE_VOIDP, Fiddle::TYPE_UINTPTR_T],
    Fiddle::TYPE_INT
)

property = '\\'
address = '\x0' *  Fiddle::SIZEOF_LONG
len = '\x0' *  Fiddle::SIZEOF_INT

result = ver_query_value.call(buffer, property, Fiddle::Pointer.to_ptr(address), Fiddle::Pointer.to_ptr(len))

puts result

if !result.zero?
    address = address.unpack('J').first
    len = len.unpack('L').first

    VS_FIXEDFILEINFO = Fiddle::CStructBuilder.create(
        Fiddle::CStruct,
        [Fiddle::TYPE_LONG] * 13,
        [
            'dwSignature',        # DWORD
            'dwStrucVersion',     # DWORD
            'dwFileVersionMS',    # DWORD
            'dwFileVersionLS',    # DWORD
            'dwProductVersionMS', # DWORD
            'dwProductVersionLS', # DWORD
            'dwFileFlagsMask',    # DWORD
            'dwFileFlags',        # DWORD
            'dwFileOS',           # DWORD
            'dwFileType',         # DWORD
            'dwFileSubtype',      # DWORD
            'dwFileDateMS',       # DWORD
            'dwFileDateLS'        # DWORD
        ]
    )

    # TODO: Check that len == VS_FIXEDFILEINFO.size
  
    struct = VS_FIXEDFILEINFO.new(address)
    
    pv = struct.dwProductVersionMS
    pv = pv << 32
    pv = pv | struct.dwProductVersionLS

    version = Array.new(4)

    3.downto(0) do |index|
        version[index] = pv & 0xffff
        pv = pv >> 16
    end

    puts version.join('.')
end