From c9d1a7845ba18466ee048666239c6b969c9acd33 Mon Sep 17 00:00:00 2001
From: "R. David Murray" <rdmurray@bitdance.com>
Date: Mon, 22 Mar 2010 15:55:09 +0000
Subject: [PATCH] Issue #7860: platform.uname now reports the correct 'machine'
 type when Python is running in WOW64 mode on 64 bit Windows.  Patch by Brian
 Curtin.

---
 Lib/platform.py           |  6 +++++-
 Lib/test/test_platform.py | 21 +++++++++++++++++++++
 Misc/NEWS                 |  3 +++
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/Lib/platform.py b/Lib/platform.py
index fc39b89b0db..080b836580c 100755
--- a/Lib/platform.py
+++ b/Lib/platform.py
@@ -1127,7 +1127,11 @@ def uname():
             # http://support.microsoft.com/kb/888731 and
             # http://www.geocities.com/rick_lively/MANUALS/ENV/MSWIN/PROCESSI.HTM
             if not machine:
-                machine = os.environ.get('PROCESSOR_ARCHITECTURE', '')
+                # WOW64 processes mask the native architecture
+                if "PROCESSOR_ARCHITEW6432" in os.environ:
+                    machine = os.environ.get("PROCESSOR_ARCHITEW6432", '')
+                else:
+                    machine = os.environ.get('PROCESSOR_ARCHITECTURE', '')
             if not processor:
                 processor = os.environ.get('PROCESSOR_IDENTIFIER', machine)
 
diff --git a/Lib/test/test_platform.py b/Lib/test/test_platform.py
index b9f1a211238..afe304238c6 100644
--- a/Lib/test/test_platform.py
+++ b/Lib/test/test_platform.py
@@ -127,6 +127,27 @@ class PlatformTest(unittest.TestCase):
         res = platform.uname()
         self.assertTrue(any(res))
 
+    @unittest.skipUnless(sys.platform.startswith('win'), "windows only test")
+    def test_uname_win32_ARCHITEW6432(self):
+        # Issue 7860: make sure we get architecture from the correct variable
+        # on 64 bit Windows: if PROCESSOR_ARCHITEW6432 exists we should be
+        # using it, per
+        # http://blogs.msdn.com/david.wang/archive/2006/03/26/HOWTO-Detect-Process-Bitness.aspx
+        try:
+            with test_support.EnvironmentVarGuard() as environ:
+                if 'PROCESSOR_ARCHITEW6432' in environ:
+                    del environ['PROCESSOR_ARCHITEW6432']
+                environ['PROCESSOR_ARCHITECTURE'] = 'foo'
+                platform._uname_cache = None
+                system, node, release, version, machine, processor = platform.uname()
+                self.assertEqual(machine, 'foo')
+                environ['PROCESSOR_ARCHITEW6432'] = 'bar'
+                platform._uname_cache = None
+                system, node, release, version, machine, processor = platform.uname()
+                self.assertEqual(machine, 'bar')
+        finally:
+            platform._uname_cache = None
+
     def test_java_ver(self):
         res = platform.java_ver()
         if sys.platform == 'java':
diff --git a/Misc/NEWS b/Misc/NEWS
index f2876d637fe..c5424c834ff 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -29,6 +29,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #7860: platform.uname now reports the correct 'machine' type
+  when Python is running in WOW64 mode on 64 bit Windows.
+
 - logging: Added getChild utility method to Logger and added isEnabledFor
   method to LoggerAdapter.