CommitLog.__init__(): Use an unlink flag to record what the behavior

should be on close.  By default, we unlink the file unless we were
passed a file-like object, in which case we don't unlink by default
(because the client owns the file).

close(): Only close the file if the file isn't already closed.  Only
unlink if the default unlink flag is true, or we're explicitly told to
unlink via the argument.  This should fix the logfile turd problem.

lib/python/BDBStorage/CommitLog.py

@@ -121,6 +121,7 @@ class CommitLog:
 
         # BAW: is our filename unique enough?  Are we opening it up with too
         # much or too little security?
+        self._unlink = 1
         if file is None:
             # Create the file from scratch.  We know the file has to be in the
             # init state, so just go ahead and write the appropriate header.
@@ -161,6 +162,7 @@ class CommitLog:
             # log.  Read the file's header and initialize our state from it.
             self._fp = file
             self._readhead()
+            self._unlink = 0
 
     def get_filename(self):
         return self._fp.name
@@ -266,14 +268,16 @@ class CommitLog:
     def next(self):
         raise NotImplementedError
 
-    def close(self, unlink=0):
+    def close(self, unlink=1):
         """Close the file.
 
         If unlink is true, delete the underlying file object too.
         """
+        if self._fp:
             self._fp.close()
-        if unlink:
+            if unlink or self._unlink:
                 os.unlink(self._fp.name)
+                self._fp = None
 
     def __del__(self):
         # Unsafe, and file preserving close