限制WebP转换时消耗的内存总量

internal/utils/buffer_pool.go

@@ -0,0 +1,48 @@
+// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package utils
+
+import "bytes"
+
+// BufferPool pool for get byte slice
+type BufferPool struct {
+	c chan *bytes.Buffer
+}
+
+// NewBufferPool 创建新对象
+func NewBufferPool(maxSize int) *BufferPool {
+	if maxSize <= 0 {
+		maxSize = 1024
+	}
+	pool := &BufferPool{
+		c: make(chan *bytes.Buffer, maxSize),
+	}
+	return pool
+}
+
+// Get 获取一个新的Buffer
+func (this *BufferPool) Get() (b *bytes.Buffer) {
+	select {
+	case b = <-this.c:
+		b.Reset()
+	default:
+		b = &bytes.Buffer{}
+	}
+	return
+}
+
+// Put 放回一个使用过的byte slice
+func (this *BufferPool) Put(b *bytes.Buffer) {
+	b.Reset()
+
+	select {
+	case this.c <- b:
+	default:
+		// 已达最大容量，则抛弃
+	}
+}
+
+// Size 当前的数量
+func (this *BufferPool) Size() int {
+	return len(this.c)
+}