dep ensure

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

@@ -0,0 +1,119 @@
+// 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 (
+	"io"
+	"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()
+}
+
+// Return 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 (me *pairPool) clear() {
+	me.Lock()
+	for _, p := range me.unused {
+		p.Close()
+	}
+	me.unused = me.unused[:0]
+	me.Unlock()
+}
+
+func (me *pairPool) used() (n int) {
+	me.Lock()
+	n = me.usedCount
+	me.Unlock()
+
+	return n
+}
+
+func (me *pairPool) total() int {
+	me.Lock()
+	n := me.usedCount + len(me.unused)
+	me.Unlock()
+	return n
+}
+
+func (me *pairPool) drop(p *Pair) {
+	p.Close()
+	me.Lock()
+	me.usedCount--
+	me.Unlock()
+}
+
+func (me *pairPool) get() (p *Pair, err error) {
+	me.Lock()
+	defer me.Unlock()
+
+	me.usedCount++
+	l := len(me.unused)
+	if l > 0 {
+		p := me.unused[l-1]
+		me.unused = me.unused[:l-1]
+		return p, nil
+	}
+
+	return newSplicePair()
+}
+
+var discardBuffer [32 * 1024]byte
+
+func DiscardAll(r io.Reader) {
+	buf := discardBuffer[:]
+	for {
+		n, _ := r.Read(buf)
+		if n < len(buf) {
+			break
+		}
+	}
+}
+
+func (me *pairPool) done(p *Pair) {
+	DiscardAll(p.r)
+
+	me.Lock()
+	me.usedCount--
+	me.unused = append(me.unused, p)
+	me.Unlock()
+}
+
+func init() {
+	splicePool = newSplicePairPool()
+}