Add gnutls_hmac_copy()
Description of the feature:
Add an API like gnutls_hmac_copy()
(or so) that copies the state of an HMAC.
Applications that this feature may be relevant to:
Required for https://gitlab.gnome.org/GNOME/glib/merge_requests/903 which is a reimplementation of GHmac using GnuTLS.
Is this feature implemented in other libraries (and which)
Yes, it's implemented in OpenSSL too: int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx);