func calcHashV1()

in image/v1.go [278:314]

• 29 lines of code
• 8 McCabe index (conditional complexity)

func calcHashV1(initialHash []byte, hdr ImageHdrV1,
	plainBody []byte) ([]byte, error) {

	hash := sha256.New()

	add := func(itf interface{}) error {
		if err := binary.Write(hash, binary.LittleEndian, itf); err != nil {
			return errors.Wrapf(err, "failed to hash data")
		}

		return nil
	}

	if initialHash != nil {
		if err := add(initialHash); err != nil {
			return nil, err
		}
	}

	if err := add(hdr); err != nil {
		return nil, err
	}

	extra := hdr.HdrSz - IMAGE_HEADER_SIZE
	if extra > 0 {
		b := make([]byte, extra)
		if err := add(b); err != nil {
			return nil, err
		}
	}

	if err := add(plainBody); err != nil {
		return nil, err
	}

	return hash.Sum(nil), nil
}