Instead of using the internal DRBG-based RNG, use the `getrandom()` system
call where available.
Keep the existing version as fall-back for other systems that don't provide
that system call.
... and for cases where auto-detection fails or the user simply wants to
use the internal RNG a new configure-switch is provided.
Signed-off-by: Steffen Jaeckel <jaeckel-floss@eyet-services.de>
Const variables in prototypes don't add much value, but make the code
larger and redundant. Remove these const keywords.
Note, this doesn't apply to pointers to const memory.
Introduced UNUSED macro with cast to void in commoh.h for internal
use. Used cast to void directly in those files which do not
include common.h. Although this change doesn't fix semantic issues
with unused function parameters, it does explicitly mark all those
places, which might require attention in future.
@sjaeckel integrated clang-format with formal coding style. Run his
script and commit changes.
There are pros and cons of this commit.
Mixed coding style is a "broken window". A good single style simplifies
reading and writing code.
On the other hand, this is a big change which will lead to conflicts.
