[Python-checkins] r58533 - python/trunk/Lib/bsddb/dbtables.py

[gregory.p.smith]

Author: gregory.p.smith
Date: Thu Oct 18 10:34:20 2007
New Revision: 58533

Modified:
   python/trunk/Lib/bsddb/dbtables.py
Log:
Fix a weird bug in dbtables: if it chose a random rowid string that contained
NULL bytes it would cause the database all sorts of problems in the future
leading to very strange random failures and corrupt dbtables.bsdTableDb dbs.


Modified: python/trunk/Lib/bsddb/dbtables.py
==============================================================================
--- python/trunk/Lib/bsddb/dbtables.py	(original)
+++ python/trunk/Lib/bsddb/dbtables.py	Thu Oct 18 10:34:20 2007
@@ -22,7 +22,6 @@
 import copy
 import random
 import struct
-import base64
 from types import ListType, StringType
 import cPickle as pickle
 
@@ -361,11 +360,12 @@
         unique = 0
         while not unique:
             # Generate a random 64-bit row ID string
-            # (note: this code has <64 bits of randomness
+            # (note: this code has <56 bits of randomness
             # but it's plenty for our database id needs!)
+            # The | 0x01010101 is to ensure no null bytes are in the value
             newid = struct.pack('ll',
-                                random.randint(0, 2147483647),
-                                random.randint(0, 2147483647))
+                                random.randint(0, 2147483647) | 0x01010101,
+                                random.randint(0, 2147483647) | 0x01010101)
 
             # Guarantee uniqueness by adding this key to the database
             try: