version.go

/*
 * Copyright (c) 2019. ENNOO - All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package proc

import (
	"github.com/aberic/gnomon"
	"sync"
)

var (
	versionInstance     *Version
	versionInstanceOnce sync.Once
)

// Version 这个文件只有一行内容，说明正在运行的内核版本。可以用标准的编程方法进行分析获得所需的系统信息
type Version struct {
	Version string
}

func obtainVersion() *Version {
	versionInstanceOnce.Do(func() {
		if nil == versionInstance {
			versionInstance = &Version{}
		}
	})
	return versionInstance
}

// Info Version 对象
func (v *Version) Info() error {
	return v.doFormatVersion(gnomon.StringBuild(FileRootPath(), "/version"))
}

// FormatVersion 将文件内容转为 Version 对象
func (v *Version) doFormatVersion(filePath string) error {
	data, err := gnomon.FileReadFirstLine(filePath)
	if nil == err {
		v.Version = data
	} else {
		return err
	}
	return nil
}