func TestQueryVersion(r io.Reader) (cachedblobstore.BlobVersion, error) {
b := make([]byte, 1)
if _, err := r.Read(b); err != nil {
if err == io.EOF {
// no data -> ver 0.
return 0, nil
}
return -1, fmt.Errorf("Failed to read 1 byte: %v", err)
}
return cachedblobstore.BlobVersion(b[0]), nil
}
func NewQueryChunkVersion(c btncrypt.Cipher) cachedblobstore.QueryVersionFunc {
return func(r io.Reader) (cachedblobstore.BlobVersion, error) {
var h ChunkHeader
if err := h.ReadFrom(r, c); err != nil {
if err == io.EOF {
return 0, nil
}
return 0, err
}
return cachedblobstore.BlobVersion(h.PayloadVersion), nil
}
}