package index import ( "io" "gopkg.in/src-d/go-git.v4/core" "gopkg.in/src-d/go-git.v4/formats/idxfile" "gopkg.in/src-d/go-git.v4/formats/packfile" ) // Index is a database of objects and their offset in a packfile. // Objects are identified by their hash. type Index map[core.Hash]int64 func New() Index { return make(Index) } // Decode decodes a idxfile into the Index func (i *Index) Decode(r io.Reader) error { d := idxfile.NewDecoder(r) idx := &idxfile.Idxfile{} if err := d.Decode(idx); err != nil { return err } for _, e := range idx.Entries { (*i)[e.Hash] = int64(e.Offset) } return nil } // NewFrompackfile returns a new index from a packfile reader. func NewFromPackfile(r io.Reader) (Index, core.Hash, error) { p := packfile.NewScannerFromReader(r) d := packfile.NewDecoder(p, nil) checksum, err := d.Decode() if err != nil { return nil, core.ZeroHash, err } index := Index(d.Index()) return index, checksum, p.Close() } // Get returns the offset that an object has the packfile. func (i Index) Get(h core.Hash) (int64, error) { o, ok := i[h] if !ok { return 0, core.ErrObjectNotFound } return o, nil } // Set adds a new hash-offset pair to the index, or substitutes an existing one. func (i Index) Set(h core.Hash, o int64) error { /*if _, ok := i[h]; ok { return fmt.Errorf("index.Set failed: duplicated key: %s", h) }*/ i[h] = o return nil }