support arch in section name as [part:platform:arch]

slapos/recipe/cmmi/README.txt

@@ -232,7 +232,11 @@ Supported options
   the former will be overridden by the latter allowing per-part customization.
 
 The recipe uses separated part to support custom options in different
-platforms. These platform's part has a pattern "part:platform".
+platforms. These platform's part has a pattern "part:platform" or
+"part:platform:arch".
+
+arch could be 'x86', 'amd64', 'ia64' ... which equals
+platform.machine().
 
 platform could be 'linux', 'cygwin', 'macos', 'sunos', 'freebsd',
 'netbsd', 'unixware' ... which equals a formatted sys.platform.

slapos/recipe/cmmi/__init__.py

@@ -23,7 +23,9 @@ class Recipe(object):
         self.name = name
 
         # Merge options if there is a matched platform section
-        platform_options = self.buildout.get("%s:%s" % (name, sys.platform))
+        platform_options = self.buildout.get(
+            "%s:%s:%s" % (name, sys.platform, self.get_machine()),
+            self.buildout.get("%s:%s" % (name, sys.platform)))
         if platform_options is None:
             self.original_options = options
         else: