| package utils |
| |
| import ( |
| "fmt" |
| "os" |
| "path/filepath" |
| "strings" |
| "syscall" |
| ) |
| |
| // TreeSize walks a directory tree and returns its total size in bytes. |
| func TreeSize(dir string) (size int64, err error) { |
| data := make(map[uint64]bool) |
| err = filepath.Walk(dir, func(d string, fileInfo os.FileInfo, e error) error { |
| // Ignore directory sizes |
| if fileInfo == nil { |
| return nil |
| } |
| |
| s := fileInfo.Size() |
| if fileInfo.IsDir() || s == 0 { |
| return nil |
| } |
| |
| // Check inode to handle hard links correctly |
| inode := fileInfo.Sys().(*syscall.Stat_t).Ino |
| if _, exists := data[inode]; exists { |
| return nil |
| } |
| data[inode] = false |
| |
| size += s |
| |
| return nil |
| }) |
| return |
| } |
| |
| // FollowSymlink will follow an existing link and scope it to the root |
| // path provided. |
| func FollowSymlinkInScope(link, root string) (string, error) { |
| prev := "/" |
| |
| root, err := filepath.Abs(root) |
| if err != nil { |
| return "", err |
| } |
| |
| link, err = filepath.Abs(link) |
| if err != nil { |
| return "", err |
| } |
| |
| if !strings.HasPrefix(filepath.Dir(link), root) { |
| return "", fmt.Errorf("%s is not within %s", link, root) |
| } |
| |
| for _, p := range strings.Split(link, "/") { |
| prev = filepath.Join(prev, p) |
| prev = filepath.Clean(prev) |
| |
| for { |
| stat, err := os.Lstat(prev) |
| if err != nil { |
| if os.IsNotExist(err) { |
| break |
| } |
| return "", err |
| } |
| if stat.Mode()&os.ModeSymlink == os.ModeSymlink { |
| dest, err := os.Readlink(prev) |
| if err != nil { |
| return "", err |
| } |
| |
| switch dest[0] { |
| case '/': |
| prev = filepath.Join(root, dest) |
| case '.': |
| prev, _ = filepath.Abs(prev) |
| |
| if prev = filepath.Clean(filepath.Join(filepath.Dir(prev), dest)); len(prev) < len(root) { |
| prev = filepath.Join(root, filepath.Base(dest)) |
| } |
| } |
| } else { |
| break |
| } |
| } |
| } |
| return prev, nil |
| } |