Previously, the unreachable code paths would have to be tagged with:
INSIST(0);
ISC_UNREACHABLE();
There was also older parts of the code that used comment annotation:
/* NOTREACHED */
Unify the handling of unreachable code paths to just use:
UNREACHABLE();
The UNREACHABLE() macro now asserts when reached and also uses
__builtin_unreachable(); when such builtin is available in the compiler.
Gcc 7+ and Clang 10+ have implemented __attribute__((fallthrough)) which
is explicit version of the /* FALLTHROUGH */ comment we are currently
using.
Add and apply FALLTHROUGH macro that uses the attribute if available,
but does nothing on older compilers.
In one case (lib/dns/zone.c), using the macro revealed that we were
using the /* FALLTHROUGH */ comment in wrong place, remove that comment.
This commit converts the license handling to adhere to the REUSE
specification. It specifically:
1. Adds used licnses to LICENSES/ directory
2. Add "isc" template for adding the copyright boilerplate
3. Changes all source files to include copyright and SPDX license
header, this includes all the C sources, documentation, zone files,
configuration files. There are notes in the doc/dev/copyrights file
on how to add correct headers to the new files.
4. Handle the rest that can't be modified via .reuse/dep5 file. The
binary (or otherwise unmodifiable) files could have license places
next to them in <foo>.license file, but this would lead to cluttered
repository and most of the files handled in the .reuse/dep5 file are
system test files.
Creation of EVP_MD_CTX and EVP_PKEY is quite expensive, so until we fix the code
to reuse the OpenSSL contexts and keys we'll use our own implementation of
siphash instead of trying to integrate with OpenSSL.
Creation of EVP_MD_CTX and EVP_PKEY is quite expensive, until
we fix the code to reuse the context and key we'll use our own
implementation of siphash.
This commits adds an OpenSSL based isc_siphash24() implementation, which is
preferred when available.
The siphash_test has been modified to test both implementation with a trick that
renames the isc_siphash24() to openssl_ or native_ prefixed name and includes
the ../siphash.c two times (when the OpenSSL implementation is available).
The native implementation's conversion from the uint8_t buffers to uint64_t now
follows the reference implementation that doesn't require aligned buffers.
