history wasn't protected by a lock.

src/ZODB/FileStorage.py

@@ -184,7 +184,7 @@
 #   may have a back pointer to a version record or to a non-version
 #   record.
 #
-__version__='$Revision: 1.38 $'[11:-2]
+__version__='$Revision: 1.39 $'[11:-2]
 
 import struct, time, os, bpthread, string, base64, sys
 from struct import pack, unpack
@@ -895,55 +895,58 @@ class FileStorage(BaseStorage.BaseStorage):
         return r
 
     def history(self, oid, version=None, length=1, filter=None):
-        r=[]
-        file=self._file
-        seek=file.seek
-        read=file.read
-        pos=self._index[oid]
-        wantver=version
+        self._lock_acquire()
+        try:
+            r=[]
+            file=self._file
+            seek=file.seek
+            read=file.read
+            pos=self._index[oid]
+            wantver=version
 
-        while 1:
-            if len(r) >= length: return r
-            seek(pos)
-            h=read(42)
-            doid,serial,prev,tloc,vlen,plen = unpack(">8s8s8s8sH8s", h)
-            prev=u64(prev)
+            while 1:
+                if len(r) >= length: return r
+                seek(pos)
+                h=read(42)
+                doid,serial,prev,tloc,vlen,plen = unpack(">8s8s8s8sH8s", h)
+                prev=u64(prev)
 
-            if vlen:
-                nv = read(8) != z64
-                file.seek(8,1) # Skip previous version record pointer
-                version=read(vlen)
-                if wantver is not None and version != wantver:
-                    if prev:
-                        pos=prev
-                        continue
-                    else:
-                        return r
-            else:
-                version=''
-                wantver=None
-            
-            seek(u64(tloc))
-            h=read(23)
-            tid, stl, status, ul, dl, el = unpack(">8s8scHHH",h)
-            if el < 0: el=t32-el
-            user_name=read(ul)
-            description=read(dl)
-            if el: d=loads(read(el))
-            else: d={}
-            
-            d['time']=TimeStamp(serial).timeTime()
-            d['user_name']=user_name
-            d['description']=description
-            d['serial']=serial
-            d['version']=version
-            d['size']=u64(plen)
-
-            if filter is None or filter(d):
-                r.append(d)
-
-            if prev: pos=prev
-            else: return r
+                if vlen:
+                    nv = read(8) != z64
+                    file.seek(8,1) # Skip previous version record pointer
+                    version=read(vlen)
+                    if wantver is not None and version != wantver:
+                        if prev:
+                            pos=prev
+                            continue
+                        else:
+                            return r
+                else:
+                    version=''
+                    wantver=None
+
+                seek(u64(tloc))
+                h=read(23)
+                tid, stl, status, ul, dl, el = unpack(">8s8scHHH",h)
+                if el < 0: el=t32-el
+                user_name=read(ul)
+                description=read(dl)
+                if el: d=loads(read(el))
+                else: d={}
+
+                d['time']=TimeStamp(serial).timeTime()
+                d['user_name']=user_name
+                d['description']=description
+                d['serial']=serial
+                d['version']=version
+                d['size']=u64(plen)
+
+                if filter is None or filter(d):
+                    r.append(d)
+
+                if prev: pos=prev
+                else: return r
+        finally: self._lock_release()
 
 
     def pack(self, t, referencesf):