Declared the interface for a file system to help with testing caching.

For the testing work in #1.
Aaron Jacobs 2015-03-17 12:38:15 +11:00
parent 920a7445eb
commit 56f503accd
1 changed files with 79 additions and 0 deletions

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// Copyright 2015 Google Inc. All Rights Reserved.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
package cachingfs
import (
// Constants that define the relative offsets of the inodes exported by the
// file system. See notes on the RenumberInodes method.
const (
FooInodeOffset = iota
// A file system with a fixed structure that looks like this:
// foo
// dir/
// bar
// The file system is configured with durations that specify how long to allow
// inode entries and attributes to be cached, used when responding to fuse
// requests. It also exposes methods for renumbering inodes and updating mtimes
// that are useful in testing that these durations are honored.
type CachingFS struct {
var _ fuse.FileSystem = &CachingFS{}
// Create a file system that issues cacheable responses according to the
// following rules:
// * LookUpInodeResponse.Entry.EntryExpiration is set according to
// lookupEntryTimeout.
// * GetInodeAttributesResponse.AttributesExpiration is set according to
// getattrTimeout.
// * Nothing else is marked cacheable. (In particular, the attributes
// returned by LookUpInode are not cacheable.)
func NewCachingFS(
lookupEntryTimeout time.Duration,
getattrTimeout time.Duration) (fs *CachingFS, err error)
// Cause inodes to receive IDs according to the following rules in further
// responses to fuse:
// * The ID of "foo" is base + FooInodeOffset.
// * The ID of "dir" is base + DirInodeOffset.
// * The ID of "dir/bar" is base + BarInodeOffset.
// If this method has never been called, the file system behaves as if it were
// called with base set to fuse.RootInodeID + 1.
// REQUIRES: base > fuse.RootInodeID
func (fs *CachingFS) RenumberInodes(base fuse.InodeID)
// Cause further queries for the attributes of inodes to use the supplied time
// as the inode's mtime.
func (fs *CachingFS) SetMtime(mtime time.Time)