1 files changed, 37 insertions, 0 deletions
diff --git a/tool/ruby_vm/loaders/vm_opts_h.rb b/tool/ruby_vm/loaders/vm_opts_h.rb
new file mode 100644
index 0000000000..f898fb36a4
--- /dev/null
+++ b/tool/ruby_vm/loaders/vm_opts_h.rb
@@ -0,0 +1,37 @@
+#! /your/favourite/path/to/ruby
+# -*- mode: ruby; coding: utf-8; indent-tabs-mode: nil; ruby-indent-level: 2 -*-
+# -*- frozen_string_literal: true; -*-
+# -*- warn_indent: true; -*-
+#
+# Copyright (c) 2017 Urabe, Shyouhei.  All rights reserved.
+#
+# This file is  a part of the programming language  Ruby.  Permission is hereby
+# granted, to  either redistribute and/or  modify this file, provided  that the
+# conditions  mentioned in  the file  COPYING are  met.  Consult  the file  for
+# details.
+
+require_relative '../helpers/scanner'
+
+json    = {}
+scanner = RubyVM::Scanner.new '../../../vm_opts.h'
+grammar = %r/
+    (?<ws>      \u0020 ){0}
+    (?<key>     \w+    ){0}
+    (?<value>   0|1    ){0}
+    (?<define>  \#define \g<ws>+ OPT_\g<key> \g<ws>+ \g<value> \g<ws>*\n )
+/mx
+
+until scanner.eos? do
+  if scanner.scan grammar then
+    json[scanner['key']] = ! scanner['value'].to_i.zero? # not nonzero?
+  else
+    scanner.scan(/.*\n/)
+  end
+end
+
+RubyVM::VmOptsH = json
+
+if __FILE__ == $0 then
+  require 'json'
+  JSON.dump RubyVM::VmOptsH, STDOUT
+end