21388: Add rpm instructions to Python READMEs

[arvados.git] / services / fuse / arvados_fuse / fusefile.py

diff --git a/services/fuse/arvados_fuse/fusefile.py b/services/fuse/arvados_fuse/fusefile.py
index 45d3db16fe00d7edb802f8d279334b312d8fcc48..a34d36eb7239664ff1ec3b94ccf060219371d699 100644 (file)
--- a/services/fuse/arvados_fuse/fusefile.py
+++ b/services/fuse/arvados_fuse/fusefile.py
@@ -2,8 +2,6 @@
 #
 # SPDX-License-Identifier: AGPL-3.0
 
-from __future__ import absolute_import
-from builtins import bytes
 import json
 import llfuse
 import logging
@@ -63,7 +61,7 @@ class FuseArvadosFile(File):
 
     def readfrom(self, off, size, num_retries=0):
         with llfuse.lock_released:
-            return self.arvfile.readfrom(off, size, num_retries, exact=True)
+            return self.arvfile.readfrom(off, size, num_retries, exact=True, return_memoryview=True)
 
     def writeto(self, off, buf, num_retries=0):
         with llfuse.lock_released:
@@ -80,9 +78,17 @@ class FuseArvadosFile(File):
             if self.writable():
                 self.arvfile.parent.root_collection().save()
 
+    def clear(self):
+        if self.parent_inode is None:
+            self.arvfile.fuse_entry = None
+            self.arvfile = None
+
 
 class StringFile(File):
     """Wrap a simple string as a file"""
+
+    __slots__ = ("contents",)
+
     def __init__(self, parent_inode, contents, _mtime):
         super(StringFile, self).__init__(parent_inode, _mtime)
         self.contents = contents
@@ -97,6 +103,8 @@ class StringFile(File):
 class ObjectFile(StringFile):
     """Wrap a dict as a serialized json object."""
 
+    __slots__ = ("object_uuid",)
+
     def __init__(self, parent_inode, obj):
         super(ObjectFile, self).__init__(parent_inode, "", 0)
         self.object_uuid = obj['uuid']
@@ -125,6 +133,9 @@ class FuncToJSONFile(StringFile):
     The function is called at the time the file is read. The result is
     cached until invalidate() is called.
     """
+
+    __slots__ = ("func",)
+
     def __init__(self, parent_inode, func):
         super(FuncToJSONFile, self).__init__(parent_inode, "", 0)
         self.func = func