Provide much simpler version of getSerial().

src/ZODB/FileStorage.py

@@ -115,7 +115,7 @@
 #   may have a back pointer to a version record or to a non-version
 #   record.
 #
-__version__='$Revision: 1.116 $'[11:-2]
+__version__='$Revision: 1.117 $'[11:-2]
 
 import base64
 from cPickle import Pickler, Unpickler, loads
@@ -573,31 +573,6 @@ class FileStorage(BaseStorage.BaseStorage,
         if plen != z64: return read(U64(plen)), version, nv
         return _loadBack(file, oid, read(8))[0], version, nv
 
-    def getSerial(self, oid):
-        self._lock_acquire()
-        try:
-            pos = self._index[oid]
-            self._file.seek(pos)
-            h = self._file.read(34)
-            _oid = h[:8]
-            if _oid != oid:
-                raise CorruptedDataError, h
-            vlen = unpack(">H", h[-2:])[0]
-            if vlen:
-                # If there is a version, find out its name and let
-                # _load() do all the work.  This is less efficient
-                # than possible, because _load() will load the pickle
-                # data.  Being more efficient is too complicated.
-                self._file.seek(24, 1) # skip plen, pnv, and pv
-                version = self._file.read(vlen)
-                pickledata, serial = self._load(oid, version,
-                                                self._index, self._file)
-                return serial
-            return h[8:16]
-        finally:
-            self._lock_release()
-
-
     def _load(self, oid, version, _index, file):
         try:
             pos = _index[oid]
@@ -1045,6 +1020,13 @@ class FileStorage(BaseStorage.BaseStorage,
         else:
             return '', ''
 
+    def getSerial(self, oid):
+        self._lock_acquire()
+        try:
+            return self._getSerial(oid, self._index[oid])
+        finally:
+            self._lock_release()
+
     def _getSerial(self, oid, pos):
         self._file.seek(pos)
         h = self._file.read(16)
@@ -1222,8 +1204,7 @@ class FileStorage(BaseStorage.BaseStorage,
         while pos < tend:
             self._file.seek(pos)
             h = self._file.read(DATA_HDR_LEN)
-            oid, serial, sprev, stloc, vlen, splen = \
-                 struct.unpack(DATA_HDR, h)
+            oid, serial, sprev, stloc, vlen, splen = struct.unpack(DATA_HDR, h)
             if failed(oid):
                 del failures[oid] # second chance!
             plen = U64(splen)