func readFileSystem(name string) (*filesystem.FileSystem, error) {
file, err := os.Open(name)
if err != nil {
return nil, err
}
defer file.Close()
var fileSystem filesystem.FileSystem
if err := gob.NewDecoder(file).Decode(&fileSystem); err != nil {
return nil, err
}
fileSystem.RebuildInodePointers()
return &fileSystem, nil
}
func spliceComputedFiles(fs *filesystem.FileSystem) error {
if *computedFiles == "" {
return nil
}
computedFileList, err := loadComputedFiles(*computedFiles)
if err != nil {
return errors.New("cannot load computed files list from: " +
*computedFiles + ": " + err.Error())
}
filenameToInodeTable := fs.FilenameToInodeTable()
inodeToFilenamesTable := fs.InodeToFilenamesTable()
for _, computedFile := range computedFileList {
inum, ok := filenameToInodeTable[computedFile.Filename]
if !ok {
return errors.New(computedFile.Filename + ": missing from image")
}
if filenames, ok := inodeToFilenamesTable[inum]; !ok {
panic(computedFile.Filename + ": no corresponding list of files")
} else if len(filenames) != 1 {
return fmt.Errorf("%s: multiple inodes: %d", computedFile.Filename,
len(filenames))
}
if inode, ok :=
fs.InodeTable[inum].(*filesystem.ComputedRegularInode); ok {
inode.Source = computedFile.Source
continue
}
if oldInode, ok := fs.InodeTable[inum].(*filesystem.RegularInode); !ok {
return fmt.Errorf("%s: type: %T is not a regular inode",
computedFile.Filename, fs.InodeTable[inum])
} else {
newInode := new(filesystem.ComputedRegularInode)
newInode.Mode = oldInode.Mode
newInode.Uid = oldInode.Uid
newInode.Gid = oldInode.Gid
newInode.Source = computedFile.Source
fs.InodeTable[inum] = newInode
}
}
fs.ComputeTotalDataBytes()
clearInodePointers(&fs.DirectoryInode, "")
return fs.RebuildInodePointers()
}