* ext/socket/mkconstants.rb: define macro if default_value is passed.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@21408 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,7 @@
+Fri Jan  9 15:40:07 2009  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* ext/socket/mkconstants.rb: define macro if default_value is passed.
+
 Fri Jan  9 13:20:08 2009  Hidetoshi NAGAI  <nagai@ai.kyutech.ac.jp>
 
 	* ext/tk/lib/tk.rb: rescue abnormal Encoding.locale_charmap value.

ext/socket/mkconstants.rb

@@ -197,13 +197,17 @@ init_constants(VALUE mConst)
 %    if guard
 #if <%=guard%>
 %    end
-#if defined(<%=name%>)
-    <%=define%>(<%=c_str name%>, <%=name%>);
 %    if default_value
-#else
-    <%=define%>(<%=c_str name%>, <%=default_value%>);
-%    end
+#ifndef <%=name%>
+#define <%=name%> <%=default_value%>
 #endif
+%    else
+#if defined(<%=name%>)
+%    end
+    <%=define%>(<%=c_str name%>, <%=name%>);
+%    unless default_value
+#endif
+%    end
 %    if guard
 #endif
 %    end