[pypy-svn] r46638 - pypy/dist/pypy/tool

[arigo at codespeak.net]

Author: arigo
Date: Sat Sep 15 15:38:24 2007
New Revision: 46638

Modified:
   pypy/dist/pypy/tool/cache.py
Log:
Protect cache building in a multithreaded py.py.


Modified: pypy/dist/pypy/tool/cache.py
==============================================================================
--- pypy/dist/pypy/tool/cache.py	(original)
+++ pypy/dist/pypy/tool/cache.py	Sat Sep 15 15:38:24 2007
@@ -25,6 +25,9 @@
 #     Be sure to call the parent __init__() if you override it.
 #
 
+from threading import RLock
+lock = RLock()     # multithreading protection
+
 
 class Cache(object):
     def __init__(self):
@@ -32,20 +35,24 @@
         self._building = {}
 
     def getorbuild(self, key):
+        lock.acquire()
         try:
-            return self.content[key]
-        except KeyError:
-            if key in self._building:
-                raise Exception, "%s recursive building of %r" % (
-                    self, key)
-            self._building[key] = True
             try:
-                result = self._build(key)
-                self.content[key] = result
-            finally:
-                del self._building[key]
-            self._ready(result)
-            return result
+                return self.content[key]
+            except KeyError:
+                if key in self._building:
+                    raise Exception, "%s recursive building of %r" % (
+                        self, key)
+                self._building[key] = True
+                try:
+                    result = self._build(key)
+                    self.content[key] = result
+                finally:
+                    del self._building[key]
+                self._ready(result)
+                return result
+        finally:
+            lock.release()
     getorbuild._annspecialcase_ = "specialize:memo"
 
     def _ready(self, result):