// Package cache implements the Fs cachepackage cache import (	"sync" 	"github.com/rclone/rclone/fs"	"github.com/rclone/rclone/lib/cache") var (	c     = cache.New()	mu    sync.Mutex            // mutex to protect remap	remap = map[string]string{} // map user supplied names to canonical names) // Lookup fsString in the mapping from user supplied names to// canonical names and return the canonical formfunc canonicalize(fsString string) string {	mu.Lock()	canonicalName, ok := remap[fsString]	mu.Unlock()	if !ok {		return fsString	}	fs.Debugf(nil, "fs cache: switching user supplied name %q for canonical name %q", fsString, canonicalName)	return canonicalName} // Put in a mapping from fsString => canonicalName if they are differentfunc addMapping(fsString, canonicalName string) {	if canonicalName == fsString {		return	}	mu.Lock()	remap[fsString] = canonicalName	mu.Unlock()} // GetFn gets an fs.Fs named fsString either from the cache or creates// it afresh with the create functionfunc GetFn(fsString string, create func(fsString string) (fs.Fs, error)) (f fs.Fs, err error) {	fsString = canonicalize(fsString)	created := false	value, err := c.Get(fsString, func(fsString string) (f interface{}, ok bool, err error) {		f, err = create(fsString)		ok = err == nil || err == fs.ErrorIsFile		created = ok		return f, ok, err	})	if err != nil && err != fs.ErrorIsFile {		return nil, err	}	f = value.(fs.Fs)	// Check we stored the Fs at the canonical name	if created {		canonicalName := fs.ConfigString(f)		if canonicalName != fsString {			fs.Debugf(nil, "fs cache: renaming cache item %q to be canonical %q", fsString, canonicalName)			value, found := c.Rename(fsString, canonicalName)			if found {				f = value.(fs.Fs)			}			addMapping(fsString, canonicalName)		}	}	return f, err} // Pin f into the cache until Unpin is calledfunc Pin(f fs.Fs) {	c.Pin(fs.ConfigString(f))} // Unpin f from the cachefunc Unpin(f fs.Fs) {	c.Pin(fs.ConfigString(f))} // Get gets an fs.Fs named fsString either from the cache or creates it afreshfunc Get(fsString string) (f fs.Fs, err error) {	return GetFn(fsString, fs.NewFs)} // Put puts an fs.Fs named fsString into the cachefunc Put(fsString string, f fs.Fs) {	canonicalName := fs.ConfigString(f)	c.Put(canonicalName, f)	addMapping(fsString, canonicalName)} // Clear removes everything from the cachefunc Clear() {	c.Clear()}