diff options
Diffstat (limited to 'plumbing/format/packfile/patch_delta.go')
| -rw-r--r-- | plumbing/format/packfile/patch_delta.go | 210 |
1 files changed, 0 insertions, 210 deletions
diff --git a/plumbing/format/packfile/patch_delta.go b/plumbing/format/packfile/patch_delta.go index 76fef4a..9e90f30 100644 --- a/plumbing/format/packfile/patch_delta.go +++ b/plumbing/format/packfile/patch_delta.go @@ -1,11 +1,9 @@ package packfile import ( - "bufio" "bytes" "errors" "io" - "math" "github.com/go-git/go-git/v5/plumbing" "github.com/go-git/go-git/v5/utils/ioutil" @@ -75,131 +73,6 @@ func PatchDelta(src, delta []byte) ([]byte, error) { return b.Bytes(), nil } -func ReaderFromDelta(h *ObjectHeader, base plumbing.EncodedObject, deltaRC io.ReadCloser) (io.ReadCloser, error) { - deltaBuf := bufio.NewReaderSize(deltaRC, 1024) - srcSz, err := decodeLEB128ByteReader(deltaBuf) - if err != nil { - if err == io.EOF { - return nil, ErrInvalidDelta - } - return nil, err - } - if srcSz != uint(base.Size()) { - return nil, ErrInvalidDelta - } - - targetSz, err := decodeLEB128ByteReader(deltaBuf) - if err != nil { - if err == io.EOF { - return nil, ErrInvalidDelta - } - return nil, err - } - remainingTargetSz := targetSz - - dstRd, dstWr := io.Pipe() - - go func() { - baseRd, err := base.Reader() - if err != nil { - _ = dstWr.CloseWithError(ErrInvalidDelta) - return - } - defer baseRd.Close() - - baseBuf := bufio.NewReader(baseRd) - basePos := uint(0) - - for { - cmd, err := deltaBuf.ReadByte() - if err == io.EOF { - _ = dstWr.CloseWithError(ErrInvalidDelta) - return - } - if err != nil { - _ = dstWr.CloseWithError(err) - return - } - - if isCopyFromSrc(cmd) { - offset, err := decodeOffsetByteReader(cmd, deltaBuf) - if err != nil { - _ = dstWr.CloseWithError(err) - return - } - sz, err := decodeSizeByteReader(cmd, deltaBuf) - if err != nil { - _ = dstWr.CloseWithError(err) - return - } - - if invalidSize(sz, targetSz) || - invalidOffsetSize(offset, sz, srcSz) { - _ = dstWr.Close() - return - } - - discard := offset - basePos - if discard < 0 { - _ = baseRd.Close() - baseRd, err = base.Reader() - if err != nil { - _ = dstWr.CloseWithError(ErrInvalidDelta) - return - } - baseBuf.Reset(baseRd) - discard = offset - } - for discard > math.MaxInt32 { - n, err := baseBuf.Discard(math.MaxInt32) - if err != nil { - _ = dstWr.CloseWithError(err) - return - } - basePos += uint(n) - discard -= uint(n) - } - for discard > 0 { - n, err := baseBuf.Discard(int(discard)) - if err != nil { - _ = dstWr.CloseWithError(err) - return - } - basePos += uint(n) - discard -= uint(n) - } - if _, err := io.Copy(dstWr, io.LimitReader(baseBuf, int64(sz))); err != nil { - _ = dstWr.CloseWithError(err) - return - } - remainingTargetSz -= sz - basePos += sz - } else if isCopyFromDelta(cmd) { - sz := uint(cmd) // cmd is the size itself - if invalidSize(sz, targetSz) { - _ = dstWr.CloseWithError(ErrInvalidDelta) - return - } - if _, err := io.Copy(dstWr, io.LimitReader(deltaBuf, int64(sz))); err != nil { - _ = dstWr.CloseWithError(err) - return - } - - remainingTargetSz -= sz - } else { - _ = dstWr.CloseWithError(ErrDeltaCmd) - return - } - if remainingTargetSz <= 0 { - _ = dstWr.Close() - return - } - } - }() - - return dstRd, nil -} - func patchDelta(dst *bytes.Buffer, src, delta []byte) error { if len(delta) < deltaSizeMin { return ErrInvalidDelta @@ -288,25 +161,6 @@ func decodeLEB128(input []byte) (uint, []byte) { return num, input[sz:] } -func decodeLEB128ByteReader(input io.ByteReader) (uint, error) { - var num, sz uint - for { - b, err := input.ReadByte() - if err != nil { - return 0, err - } - - num |= (uint(b) & payload) << (sz * 7) // concats 7 bits chunks - sz++ - - if uint(b)&continuation == 0 { - break - } - } - - return num, nil -} - const ( payload = 0x7f // 0111 1111 continuation = 0x80 // 1000 0000 @@ -320,40 +174,6 @@ func isCopyFromDelta(cmd byte) bool { return (cmd&0x80) == 0 && cmd != 0 } -func decodeOffsetByteReader(cmd byte, delta io.ByteReader) (uint, error) { - var offset uint - if (cmd & 0x01) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - offset = uint(next) - } - if (cmd & 0x02) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - offset |= uint(next) << 8 - } - if (cmd & 0x04) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - offset |= uint(next) << 16 - } - if (cmd & 0x08) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - offset |= uint(next) << 24 - } - - return offset, nil -} - func decodeOffset(cmd byte, delta []byte) (uint, []byte, error) { var offset uint if (cmd & 0x01) != 0 { @@ -388,36 +208,6 @@ func decodeOffset(cmd byte, delta []byte) (uint, []byte, error) { return offset, delta, nil } -func decodeSizeByteReader(cmd byte, delta io.ByteReader) (uint, error) { - var sz uint - if (cmd & 0x10) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - sz = uint(next) - } - if (cmd & 0x20) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - sz |= uint(next) << 8 - } - if (cmd & 0x40) != 0 { - next, err := delta.ReadByte() - if err != nil { - return 0, err - } - sz |= uint(next) << 16 - } - if sz == 0 { - sz = 0x10000 - } - - return sz, nil -} - func decodeSize(cmd byte, delta []byte) (uint, []byte, error) { var sz uint if (cmd & 0x10) != 0 { |