test.rb

# coding: utf-8

repo_path = ARGV.first || '/usr/src/ruby-2.4.2' # path to ruby repo
section_name = "rdata"

def process_binary obj_name, section_name
    binary = open(obj_name, "rb"){|f|f.read}
    offset = `objdump -h -j .#{section_name} #{obj_name}`[/\.#{section_name}.*?(\w+)\s+\S+$/, 1].to_i(16)
    `nm --defined-only #{obj_name}`.split("\n").map{|s|s.split(/\s+/)}.each do |address, _, name|
        yield name, binary, address.to_i(16) + offset
    end
end

process_binary "#{repo_path}/enc/unicode.o", section_name do |name, binary, address|
    if name =~ /CR_*/
        size = binary[address, 4].unpack("l")
        address += 4
        open("test/" + name, "wb") do |f|
            f << [size[0] * 2 + 1].pack("N")
            f << size.pack("N")

            address.step(address + (size[0] * 2 * 4 - 1), 4).each do |adr|
                f << binary[adr, 4].unpack("l").pack("N")
            end
        end
    end
end