[libvirt] [PATCH 2/5] Introduce virCryptoHashBuf

[Michal Privoznik]

On 05/11/2018 05:50 PM, Ján Tomko wrote:
> A function that keeps the hash in binary form instead of converting
> it to human-readable hexadecimal form.
> 
> Signed-off-by: Ján Tomko <jtomko at redhat.com>
> ---
>  src/util/vircrypto.c | 31 +++++++++++++++++++++----------
>  src/util/vircrypto.h |  7 +++++++
>  2 files changed, 28 insertions(+), 10 deletions(-)
> 
> diff --git a/src/util/vircrypto.c b/src/util/vircrypto.c
> index 48b04fc8ce..1a2dcc28b7 100644
> --- a/src/util/vircrypto.c
> +++ b/src/util/vircrypto.c
> @@ -54,28 +54,39 @@ struct virHashInfo {
>  verify(ARRAY_CARDINALITY(hashinfo) == VIR_CRYPTO_HASH_LAST);
>  
>  int
> -virCryptoHashString(virCryptoHash hash,
> -                    const char *input,
> -                    char **output)
> +virCryptoHashBuf(virCryptoHash hash,
> +                 const char *input,
> +                 unsigned char *output)
>  {
> -    unsigned char buf[VIR_CRYPTO_LARGEST_DIGEST_SIZE];
> -    size_t hashstrlen;
> -    size_t i;
> -
>      if (hash >= VIR_CRYPTO_HASH_LAST) {
>          virReportError(VIR_ERR_INVALID_ARG,
>                         _("Unknown crypto hash %d"), hash);
>          return -1;
>      }

This check feels useless. It's like if we were checking a value before
passing it to vir*TypeToString(). But it's pre-existing, so you have my
ACK. But a follow up patch removing it (=trivial) would be nice.

Also, don't forget to export the symbol in libvirt_private.syms ;-)
I'm wondering how linker succeeds in 3/5 where you use the function
without it being exported. Maybe my compiler decided to inline this
function?

Michal