minio/docs/debugging/xattr/main.go

118 lines
3.2 KiB
Go

// Copyright (c) 2015-2023 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package main
import (
"encoding/binary"
"errors"
"flag"
"fmt"
"log"
"os"
"github.com/olekukonko/tablewriter"
"github.com/pkg/xattr"
)
var (
path, name string
value uint64
set, list bool
)
func getxattr(path, name string) (uint64, error) {
buf, err := xattr.LGet(path, name)
if err != nil {
return 0, err
}
return binary.LittleEndian.Uint64(buf[:8]), nil
}
func listxattr(path string) ([]string, error) {
return xattr.LList(path)
}
func setxattr(path, name string, value uint64) error {
data := make([]byte, 8)
binary.LittleEndian.PutUint64(data, value)
return xattr.LSet(path, name, data)
}
func main() {
flag.StringVar(&path, "path", "", "path name where the attribute shall be applied")
flag.StringVar(&name, "name", "", "attribute name or it can be a wildcard if '.' is specified")
flag.Uint64Var(&value, "value", 0, "attribute value expects the value to be uint64")
flag.BoolVar(&set, "set", false, "this is a set attribute operation")
flag.Parse()
if set && value == 0 {
log.Fatalln("setting an attribute requires a non-zero value")
}
if !set && value > 0 {
log.Fatalln("to set a value please specify --set along with --value")
}
table := tablewriter.NewWriter(os.Stdout)
table.SetHeader([]string{"Name", "Value"})
table.SetAutoWrapText(false)
table.SetAutoFormatHeaders(true)
table.SetHeaderAlignment(tablewriter.ALIGN_LEFT)
table.SetAlignment(tablewriter.ALIGN_LEFT)
table.SetCenterSeparator("")
table.SetColumnSeparator("")
table.SetRowSeparator("")
table.SetHeaderLine(false)
// table.EnableBorder(false)
table.SetTablePadding("\t") // pad with tabs
table.SetNoWhiteSpace(true)
if set {
if err := setxattr(path, name, value); err != nil {
log.Fatalln(fmt.Errorf("setting attribute %s failed with: %v", name, err))
}
} else {
if name == "" {
log.Fatalln("you must specify an attribute name for reading")
}
var names []string
if name == "." {
attrs, err := listxattr(path)
if err != nil {
log.Fatalln(fmt.Errorf("listing attributes failed with: %v", err))
}
names = append(names, attrs...)
} else {
names = append(names, name)
}
var data [][]string
for _, attr := range names {
value, err := getxattr(path, attr)
if err != nil {
data = append(data, []string{attr, errors.Unwrap(err).Error()})
} else {
data = append(data, []string{attr, fmt.Sprintf("%d", value)})
}
}
table.AppendBulk(data) // Add Bulk Data
table.Render()
}
}