缓存策略移除“容纳Key数量”选项；缓存占用空间统计改成统计缓存目录所在文件系统

internal/utils/fs/stat.go

@@ -0,0 +1,81 @@
+// Copyright 2023 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
+
+package fsutils
+
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/utils/fasttime"
+	"golang.org/x/sys/unix"
+	"sync"
+)
+
+// Stat device contains the path
+func Stat(path string) (*StatResult, error) {
+	var stat = &unix.Statfs_t{}
+	err := unix.Statfs(path, stat)
+	if err != nil {
+		return nil, err
+	}
+	return NewStatResult(stat), nil
+}
+
+var locker = &sync.RWMutex{}
+var cacheMap = map[string]*StatResult{} // path => StatResult
+
+const cacheLife = 3 // seconds
+
+// StatCache stat device with cache
+func StatCache(path string) (*StatResult, error) {
+	locker.RLock()
+	stat, ok := cacheMap[path]
+	if ok && stat.updatedAt >= fasttime.Now().Unix()-cacheLife {
+		locker.RUnlock()
+		return stat, nil
+	}
+	locker.RUnlock()
+
+	locker.Lock()
+	defer locker.Unlock()
+
+	stat, err := Stat(path)
+	if err != nil {
+		return nil, err
+	}
+
+	cacheMap[path] = stat
+	return stat, nil
+}
+
+type StatResult struct {
+	rawStat   *unix.Statfs_t
+	blockSize uint64
+
+	updatedAt int64
+}
+
+func NewStatResult(rawStat *unix.Statfs_t) *StatResult {
+	var blockSize = rawStat.Bsize
+	if blockSize < 0 {
+		blockSize = 0
+	}
+
+	return &StatResult{
+		rawStat:   rawStat,
+		blockSize: uint64(blockSize),
+		updatedAt: fasttime.Now().Unix(),
+	}
+}
+
+func (this *StatResult) AvailableSize() uint64 {
+	return this.rawStat.Bavail * this.blockSize
+}
+
+func (this *StatResult) TotalSize() uint64 {
+	return this.rawStat.Blocks * this.blockSize
+}
+
+func (this *StatResult) UsedSize() uint64 {
+	if this.rawStat.Bavail <= this.rawStat.Blocks {
+		return (this.rawStat.Blocks - this.rawStat.Bavail) * this.blockSize
+	}
+	return 0
+}