diff options
Diffstat (limited to 'formats/objfile/reader.go')
-rw-r--r-- | formats/objfile/reader.go | 118 |
1 files changed, 0 insertions, 118 deletions
diff --git a/formats/objfile/reader.go b/formats/objfile/reader.go deleted file mode 100644 index 5c319f6..0000000 --- a/formats/objfile/reader.go +++ /dev/null @@ -1,118 +0,0 @@ -package objfile - -import ( - "compress/zlib" - "errors" - "io" - "strconv" - - "gopkg.in/src-d/go-git.v4/core" - "gopkg.in/src-d/go-git.v4/formats/packfile" -) - -var ( - ErrClosed = errors.New("objfile: already closed") - ErrHeader = errors.New("objfile: invalid header") - ErrNegativeSize = errors.New("objfile: negative object size") -) - -// Reader reads and decodes compressed objfile data from a provided io.Reader. -// Reader implements io.ReadCloser. Close should be called when finished with -// the Reader. Close will not close the underlying io.Reader. -type Reader struct { - multi io.Reader - zlib io.ReadCloser - hasher core.Hasher -} - -// NewReader returns a new Reader reading from r. -func NewReader(r io.Reader) (*Reader, error) { - zlib, err := zlib.NewReader(r) - if err != nil { - return nil, packfile.ErrZLib.AddDetails(err.Error()) - } - - return &Reader{ - zlib: zlib, - }, nil -} - -// Header reads the type and the size of object, and prepares the reader for read -func (r *Reader) Header() (t core.ObjectType, size int64, err error) { - var raw []byte - raw, err = r.readUntil(' ') - if err != nil { - return - } - - t, err = core.ParseObjectType(string(raw)) - if err != nil { - return - } - - raw, err = r.readUntil(0) - if err != nil { - return - } - - size, err = strconv.ParseInt(string(raw), 10, 64) - if err != nil { - err = ErrHeader - return - } - - defer r.prepareForRead(t, size) - return -} - -// readSlice reads one byte at a time from r until it encounters delim or an -// error. -func (r *Reader) readUntil(delim byte) ([]byte, error) { - var buf [1]byte - value := make([]byte, 0, 16) - for { - if n, err := r.zlib.Read(buf[:]); err != nil && (err != io.EOF || n == 0) { - if err == io.EOF { - return nil, ErrHeader - } - return nil, err - } - - if buf[0] == delim { - return value, nil - } - - value = append(value, buf[0]) - } -} - -func (r *Reader) prepareForRead(t core.ObjectType, size int64) { - r.hasher = core.NewHasher(t, size) - r.multi = io.TeeReader(r.zlib, r.hasher) -} - -// Read reads len(p) bytes into p from the object data stream. It returns -// the number of bytes read (0 <= n <= len(p)) and any error encountered. Even -// if Read returns n < len(p), it may use all of p as scratch space during the -// call. -// -// If Read encounters the end of the data stream it will return err == io.EOF, -// either in the current call if n > 0 or in a subsequent call. -func (r *Reader) Read(p []byte) (n int, err error) { - return r.multi.Read(p) -} - -// Hash returns the hash of the object data stream that has been read so far. -func (r *Reader) Hash() core.Hash { - return r.hasher.Sum() -} - -// Close releases any resources consumed by the Reader. Calling Close does not -// close the wrapped io.Reader originally passed to NewReader. -func (r *Reader) Close() error { - if err := r.zlib.Close(); err != nil { - return err - } - - return nil -} |