Helper for link window's library

lib/mruby/gem.rb

@@ -106,6 +106,15 @@ module MRuby
         define_gem_init_builder if @generate_functions
       end
 
+      def for_windows?
+        if build.kind_of?(MRuby::CrossBuild)
+          return %w(x86_64-w64-mingw32 i686-w64-mingw32).include?(build.host_target)
+        elsif build.kind_of?(MRuby::Build)
+          return ('A'..'Z').to_a.any? { |vol| Dir.exist?("#{vol}:") }
+        end
+        return false
+      end
+
       def add_dependency(name, *requirements)
         default_gem = requirements.last.kind_of?(Hash) ? requirements.pop : nil
         requirements = ['>= 0.0.0'] if requirements.empty?

mrbgems/mruby-io/mrbgem.rake

@@ -5,26 +5,10 @@ MRuby::Gem::Specification.new('mruby-io') do |spec|
 
   spec.cc.include_paths << "#{build.root}/src"
 
-  case RUBY_PLATFORM
-  when /mingw|mswin|msys/
-    really_for_window = true
-
-    if build.kind_of?(MRuby::CrossBuild)
-      if %w(x86_64-w64-mingw32 i686-w64-mingw32).include?(build.host_target)
-        really_for_window = true
-      else
-        really_for_window = false
-      end
-    end
-
-    if really_for_window
-      spec.linker.libraries += ['Ws2_32']
-      #spec.cc.include_paths += ["C:/Windows/system/include"]
-      spec.linker.library_paths += ["C:/Windows/system"]
-    end
-  end
-  if build.kind_of?(MRuby::CrossBuild) && %w(x86_64-w64-mingw32 i686-w64-mingw32).include?(build.host_target)
-    spec.linker.libraries += ['ws2_32']
+  if for_windows?
+    spec.linker.libraries += ['Ws2_32']
+    #spec.cc.include_paths += ["C:/Windows/system/include"]
+    spec.linker.library_paths += ["C:/Windows/system"]
   end
   spec.add_test_dependency 'mruby-time', core: 'mruby-time'
 end

mrbgems/mruby-socket/mrbgem.rake

@@ -7,21 +7,9 @@ MRuby::Gem::Specification.new('mruby-socket') do |spec|
   #spec.cc.defines << "HAVE_SA_LEN=0"
 
   # If Windows, use winsock
-  if ( /mswin|mingw|win32/ =~ RUBY_PLATFORM ) then
-    really_for_window = true
-
-    if build.kind_of?(MRuby::CrossBuild)
-      if %w(x86_64-w64-mingw32 i686-w64-mingw32).include?(build.host_target)
-        really_for_window = true
-      else
-        really_for_window = false
-      end
-    end
-
-    if really_for_window
-      spec.linker.libraries << "wsock32"
-      spec.linker.libraries << "ws2_32"
-    end
+  if for_windows?
+    spec.linker.libraries << "wsock32"
+    spec.linker.libraries << "ws2_32"
   end
 
   spec.add_dependency('mruby-io', :core => 'mruby-io')