// Copyright 2024 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
//go:build plus

package caches

import (
	"github.com/TeaOSLab/EdgeNode/internal/utils/mmap"
	"os"
)

func (this *FileStorage) tryMMAPReader(isPartial bool, estimatedSize int64, path string) (Reader, error) {
	// TODO 因为在实践中MMAP耗费了太多CPU，在未解决之前先暂停支持
	return nil, nil
	var options = this.options // copy
	if estimatedSize > 0 &&
		!isPartial &&
		(options != nil && options.EnableMMAP) &&
		IsValidForMMAPSize(estimatedSize) {
		var isOk bool
		defer func() {
			if !isOk {
				_ = this.removeCacheFile(path)
			}
		}()

		sharedMMAP, err := mmap.OpenSharedMMAP(path)
		if err != nil {
			if os.IsNotExist(err) {
				isOk = true
				return nil, ErrNotFound
			}
			return nil, err
		}

		reader, err := NewMMAPFileReader(sharedMMAP)
		if err != nil {
			if os.IsNotExist(err) {
				isOk = true
				return nil, ErrNotFound
			}
			return nil, err
		}

		err = reader.Init()
		if err != nil {
			if os.IsNotExist(err) {
				isOk = true
				return nil, ErrNotFound
			}
			return nil, err
		}

		isOk = true
		return reader, nil
	}

	return nil, nil
}