rclone/vendor/github.com/hanwen/go-fuse/v2/splice/pool.go

105 lines
1.5 KiB
Go

// Copyright 2016 the Go-FUSE Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package splice
import (
"sync"
)
var splicePool *pairPool
type pairPool struct {
sync.Mutex
unused []*Pair
usedCount int
}
func ClearSplicePool() {
splicePool.clear()
}
func Get() (*Pair, error) {
return splicePool.get()
}
func Total() int {
return splicePool.total()
}
func Used() int {
return splicePool.used()
}
// Done returns the pipe pair to pool.
func Done(p *Pair) {
splicePool.done(p)
}
// Closes and discards pipe pair.
func Drop(p *Pair) {
splicePool.drop(p)
}
func newSplicePairPool() *pairPool {
return &pairPool{}
}
func (pp *pairPool) clear() {
pp.Lock()
for _, p := range pp.unused {
p.Close()
}
pp.unused = pp.unused[:0]
pp.Unlock()
}
func (pp *pairPool) used() (n int) {
pp.Lock()
n = pp.usedCount
pp.Unlock()
return n
}
func (pp *pairPool) total() int {
pp.Lock()
n := pp.usedCount + len(pp.unused)
pp.Unlock()
return n
}
func (pp *pairPool) drop(p *Pair) {
p.Close()
pp.Lock()
pp.usedCount--
pp.Unlock()
}
func (pp *pairPool) get() (p *Pair, err error) {
pp.Lock()
defer pp.Unlock()
pp.usedCount++
l := len(pp.unused)
if l > 0 {
p := pp.unused[l-1]
pp.unused = pp.unused[:l-1]
return p, nil
}
return newSplicePair()
}
func (pp *pairPool) done(p *Pair) {
p.discard()
pp.Lock()
pp.usedCount--
pp.unused = append(pp.unused, p)
pp.Unlock()
}
func init() {
splicePool = newSplicePairPool()
}