seaweedfs/weed/util/file_util.go

142 lines
2.9 KiB
Go

package util
import (
"bytes"
"crypto/sha256"
"errors"
"fmt"
"github.com/seaweedfs/seaweedfs/weed/glog"
"os"
"os/user"
"path/filepath"
"strings"
"time"
)
const maxFilenameLength = 255
func TestFolderWritable(folder string) (err error) {
fileInfo, err := os.Stat(folder)
if err != nil {
return err
}
if !fileInfo.IsDir() {
return errors.New("Not a valid folder!")
}
perm := fileInfo.Mode().Perm()
glog.V(0).Infoln("Folder", folder, "Permission:", perm)
if 0200&perm != 0 {
return nil
}
return errors.New("Not writable!")
}
func GetFileSize(file *os.File) (size int64, err error) {
var fi os.FileInfo
if fi, err = file.Stat(); err == nil {
size = fi.Size()
}
return
}
func FileExists(filename string) bool {
_, err := os.Stat(filename)
if os.IsNotExist(err) {
return false
}
return true
}
func FolderExists(folder string) bool {
fileInfo, err := os.Stat(folder)
if err != nil {
return false
}
return fileInfo.IsDir()
}
func CheckFile(filename string) (exists, canRead, canWrite bool, modTime time.Time, fileSize int64) {
exists = true
fi, err := os.Stat(filename)
if os.IsNotExist(err) {
exists = false
return
}
if err != nil {
glog.Errorf("check %s: %v", filename, err)
return
}
if fi.Mode()&0400 != 0 {
canRead = true
}
if fi.Mode()&0200 != 0 {
canWrite = true
}
modTime = fi.ModTime()
fileSize = fi.Size()
return
}
func ResolvePath(path string) string {
if !strings.Contains(path, "~") {
return path
}
usr, _ := user.Current()
dir := usr.HomeDir
if path == "~" {
// In case of "~", which won't be caught by the "else if"
path = dir
} else if strings.HasPrefix(path, "~/") {
// Use strings.HasPrefix so we don't match paths like
// "/something/~/something/"
path = filepath.Join(dir, path[2:])
}
return path
}
func FileNameBase(filename string) string {
lastDotIndex := strings.LastIndex(filename, ".")
if lastDotIndex < 0 {
return filename
}
return filename[:lastDotIndex]
}
func ToShortFileName(path string) string {
fileName := filepath.Base(path)
if fileNameBytes := []byte(fileName); len(fileNameBytes) > maxFilenameLength {
shaStr := fmt.Sprintf("%x", sha256.Sum256(fileNameBytes))
fileNameBase := FileNameBase(fileName)
fileExt := fileName[len(fileNameBase):]
fileNameBaseBates := bytes.ToValidUTF8([]byte(fileNameBase)[:maxFilenameLength-len([]byte(fileExt))-8], []byte{})
shortFileName := string(fileNameBaseBates) + shaStr[len(shaStr)-8:]
return filepath.Join(filepath.Dir(path), shortFileName) + fileExt
}
return path
}
// Copied from os.WriteFile(), adding file sync.
// see https://github.com/golang/go/issues/20599
func WriteFile(name string, data []byte, perm os.FileMode) error {
f, err := os.OpenFile(name, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
if err != nil {
return err
}
_, err = f.Write(data)
if err1 := f.Sync(); err1 != nil && err == nil {
err = err1
}
if err1 := f.Close(); err1 != nil && err == nil {
err = err1
}
return err
}