Since BIND 9 headers are not longer public, there's no reason to keep
the ISC_LANG_BEGINDECL and ISC_LANG_ENDDECL macros to support including
them from C++ projects.
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.
Unify the header guard style and replace the inconsistent include guards
with #pragma once.
The #pragma once is widely and very well supported in all compilers that
BIND 9 supports, and #pragma once was already in use in several new or
refactored headers.
Using simpler method will also allow us to automate header guard checks
as this is simpler to programatically check.
For reference, here are the reasons for the change taken from
Wikipedia[1]:
> In the C and C++ programming languages, #pragma once is a non-standard
> but widely supported preprocessor directive designed to cause the
> current source file to be included only once in a single compilation.
>
> Thus, #pragma once serves the same purpose as include guards, but with
> several advantages, including: less code, avoidance of name clashes,
> and sometimes improvement in compilation speed. On the other hand,
> #pragma once is not necessarily available in all compilers and its
> implementation is tricky and might not always be reliable.
1. https://en.wikipedia.org/wiki/Pragma_once
The Windows support has been completely removed from the source tree
and BIND 9 now no longer supports native compilation on Windows.
We might consider reviewing mingw-w64 port if contributed by external
party, but no development efforts will be put into making BIND 9 compile
and run on Windows again.
3746. [func] New "max-zone-ttl" option enforces maximum
TTLs for zones. If loading a zone containing a
higher TTL, the load fails. DDNS updates with
higher TTLs are accepted but the TTL is truncated.
(Note: Currently supported for master zones only;
inline-signing slaves will be added.) [RT #38405]
include the serial number of the zone from which
they were generated, if different (as in the case
of inline-signing zones). This is to be used in
inline-signing zones, to track changes between the
unsigned and signed versions of the zone, which may
have different serial numbers.
(Note: raw zonefiles generated by this version of
BIND are no longer compatble with prior versions.
To generate a backward-compatible raw zonefile
using dnssec-signzone or named-compilezone, specify
output format "raw=0" instead of simply "raw".)
[RT #26587]
improving loading performance. The masterfile-format
option in named.conf can be used to specify a
non-default format. A new separate command
named-compilezone was provided to generate zone files
in a new format.
named-checkzone has extended checking of NS, MX and
SRV record and the hosts they reference.
named has extended post zone load checks.
New zone options: check-mx and integrity-check.
[RT #4940]
