[Zope-Checkins] CVS: Zope/lib/python/OFS - Image.py:1.143

[Martijn Pieters]

Update of /cvs-repository/Zope/lib/python/OFS
In directory cvs.zope.org:/tmp/cvs-serv23953/lib/python/OFS

Modified Files:
	Image.py 
Log Message:
Fix for Collector issue #671: PData chains are of equal length, except the
*first* entry (and not the last one as assumed before).

- Adjust test to create a big file that will have a Pdata entry of smaller
  size

- Fix pdata_map lookups with first-entry-size in mind.


=== Zope/lib/python/OFS/Image.py 1.142 => 1.143 ===
--- Zope/lib/python/OFS/Image.py:1.142	Fri Oct  4 15:50:34 2002
+++ Zope/lib/python/OFS/Image.py	Wed Nov 13 14:17:44 2002
@@ -323,7 +323,13 @@
                             # calculations allow us to fast-forward through the
                             # Pdata chain without a lot of dereferencing if we
                             # did the work already.
-                            closest_pos = start - (start % (1<<16))
+                            first_size = len(pdata_map[0].data)
+                            if start < first_size:
+                                closest_pos = 0
+                            else:
+                                closest_pos = (
+                                    ((start - first_size) >> 16 << 16) +
+                                    first_size)
                             pos = min(closest_pos, max(pdata_map.keys()))
                             data = pdata_map[pos]