Fix many warnings on Python 3

Many more remain.

src/ZODB/FileStorage/FileStorage.py

@@ -962,9 +962,10 @@ class FileStorage(
                             # We're undoing a blob modification operation.
                             # We have to copy the blob data
                             tmp = ZODB.utils.mktemp(dir=self.fshelper.temp_dir)
-                            ZODB.utils.cp(
-                                self.openCommittedBlobFile(h.oid, userial),
-                                open(tmp, 'wb'))
+                            with open(tmp, 'wb') as fp:
+                                ZODB.utils.cp(
+                                    self.openCommittedBlobFile(h.oid, userial),
+                                    fp)
                             self._blob_storeblob(h.oid, self._tid, tmp)
 
                 new = DataHeader(h.oid, self._tid, ipos, otloc, 0, len(p))
@@ -1180,7 +1181,8 @@ class FileStorage(
             handle_dir = ZODB.blob.remove_committed_dir
 
         # Fist step: move or remove oids or revisions
-        for line in open(os.path.join(self.blob_dir, '.removed'), 'rb'):
+        fp = open(os.path.join(self.blob_dir, '.removed'), 'rb')
+        for line in fp:
             line = binascii.unhexlify(line.strip())
 
             if len(line) == 8:
@@ -1194,6 +1196,7 @@ class FileStorage(
                 continue
 
             if len(line) != 16:
+                fp.close()
                 raise ValueError("Bad record in ", self.blob_dir, '.removed')
 
             oid, tid = line[:8], line[8:]
@@ -1205,6 +1208,7 @@ class FileStorage(
             assert not os.path.exists(path)
             maybe_remove_empty_dir_containing(path)
 
+        fp.close()
         os.remove(os.path.join(self.blob_dir, '.removed'))
 
         if not self.pack_keep_old:

src/ZODB/FileStorage/fspack.py

@@ -347,6 +347,7 @@ class FileStoragePacker(FileStorageFormatter):
                 os.path.join(storage.blob_dir, '.removed'), 'wb')
         else:
             self.pack_blobs = False
+            self.blob_removed = None
 
         path = storage._file.name
         self._name = path
@@ -412,6 +413,8 @@ class FileStoragePacker(FileStorageFormatter):
             self._tfile.close()
             self._file.close()
             os.remove(self._name + ".pack")
+            if self.blob_removed is not None:
+                self.blob_removed.close()
             return None
         self._commit_lock_acquire()
         self.locked = True
@@ -446,6 +449,8 @@ class FileStoragePacker(FileStorageFormatter):
             self._tfile.flush()
             self._tfile.close()
             self._file.close()
+            if self.blob_removed is not None:
+                self.blob_removed.close()
 
             return pos
         except:

src/ZODB/blob.py

@@ -178,7 +178,8 @@ class Blob(persistent.Persistent):
                     self._create_uncommitted_file()
                     result = BlobFile(self._p_blob_uncommitted, mode, self)
                     if self._p_blob_committed:
-                        utils.cp(open(self._p_blob_committed, 'rb'), result)
+                        with open(self._p_blob_committed, 'rb') as fp:
+                            utils.cp(fp, result)
                         if mode == 'r+':
                             result.seek(0)
                 else:
@@ -356,7 +357,7 @@ class FilesystemHelper:
                 layout_marker.write(self.layout_name)
         else:
             with open(layout_marker_path, 'r') as layout_marker:
-                layout = open(layout_marker_path, 'r').read().strip()
+                layout = layout_marker.read().strip()
             if layout != self.layout_name:
                 raise ValueError(
                     "Directory layout `%s` selected for blob directory %s, but "
@@ -508,8 +509,8 @@ def auto_layout_select(path):
     # use.
     layout_marker = os.path.join(path, LAYOUT_MARKER)
     if os.path.exists(layout_marker):
-        layout = open(layout_marker, 'r').read()
-        layout = layout.strip()
+        with open(layout_marker, 'r') as fp:
+            layout = fp.read().strip()
         log('Blob directory `%s` has layout marker set. '
             'Selected `%s` layout. ' % (path, layout), level=logging.DEBUG)
     elif not os.path.exists(path):
@@ -960,7 +961,8 @@ def copyTransactionsFromTo(source, destination):
                 fd, name = tempfile.mkstemp(
                     suffix='.tmp', dir=destination.fshelper.temp_dir)
                 os.close(fd)
-                utils.cp(open(blobfilename, 'rb'), open(name, 'wb'))
+                with open(blobfilename, 'rb') as sf, open(name, 'wb') as df:
+                    utils.cp(sf, df)
                 destination.restoreBlob(record.oid, record.tid, record.data,
                                  name, record.data_txn, trans)
             else:

src/ZODB/fsrecover.py

@@ -387,6 +387,7 @@ def recover(inp, outp, verbose=0, partial=False, force=False, pack=None):
         ofs.pack(pack, referencesf)
 
     ofs.close()
+    f.close()
 
 if __name__ == "__main__":
     main()

src/ZODB/tests/testFileStorage.py

@@ -91,7 +91,8 @@ class FileStorageTests(
         newindex = dict(index)
         data['index'] = newindex
 
-        dump(data, open('FileStorageTests.fs.index', 'wb'), 1)
+        with open('FileStorageTests.fs.index', 'wb') as fp:
+            dump(data, fp, 1)
         return index
 
     def check_conversion_to_fsIndex(self, read_only=False):

src/ZODB/tests/testRecover.py

@@ -13,7 +13,6 @@
 ##############################################################################
 """Tests of the file storage recovery script."""
 
-import base64
 import os
 import random
 import sys
@@ -22,6 +21,7 @@ import unittest
 import ZODB
 import ZODB.tests.util
 from ZODB.FileStorage import FileStorage
+from ZODB._compat import decodebytes
 import ZODB.fsrecover
 
 from persistent.mapping import PersistentMapping
@@ -152,11 +152,11 @@ class RecoverTest(ZODB.tests.util.TestCase):
 
         L = self.storage.undoLog()
         r = L[3]
-        tid = base64.decodestring(r["id"] + b"\n")
+        tid = decodebytes(r["id"] + b"\n")
         pos1 = self.storage._txn_find(tid, 0)
 
         r = L[8]
-        tid = base64.decodestring(r["id"] + b"\n")
+        tid = decodebytes(r["id"] + b"\n")
         pos2 = self.storage._txn_find(tid, 0)
 
         self.storage.close()
@@ -190,7 +190,7 @@ class RecoverTest(ZODB.tests.util.TestCase):
         # Find a transaction near the end.
         L = self.storage.undoLog()
         r = L[1]
-        tid = base64.decodestring(r["id"] + b"\n")
+        tid = decodebytes(r["id"] + b"\n")
         pos = self.storage._txn_find(tid, 0)
 
         # Overwrite its status with 'c'.

src/ZODB/tests/testfsIndex.py

@@ -221,7 +221,8 @@ Note that we pass a file position, which gets saved with the index data.
 If we save the data in the old format, we can still read it:
 
     >>> from ZODB._compat import dump
-    >>> dump(dict(pos=42, index=index), open('old', 'wb'), 1)
+    >>> with open('old', 'wb') as fp:
+    ...     dump(dict(pos=42, index=index), fp, 1)
     >>> info = fsIndex.load('old')
     >>> info['pos']
     42