Move the macOS section of <isc/endian.h> to a lower spot as it is
believed not to be the most popular platform for running BIND. Add a
comment and remove redundant definitions.
Instead of only supporting Linux, try making <isc/endian.h> support
other GNU platforms as well. Since some compilers define __GNUC__ on
BSDs (e.g. Clang on FreeBSD), move the relevant section to the bottom of
the platform-specific part of <isc/endian.h>, so that it only gets
evaluated when more specific platform determination criteria are not
met. Also include <byteswap.h> so that any byte-swapping macros which
may be defined in that file on older platforms are used in the fallback
definitions of the nonstandard hto[bl]e{16,32,64}() and
[bl]e{16,32,64}toh() conversion functions.
While Solaris does not support the nonstandard hto[bl]e{16,32,64}() and
[bl]e{16,32,64}toh() conversion functions, it does have some
byte-swapping macros available in <sys/byteorder.h>. Ensure these
macros are used in the fallback definitions of the aforementioned
nonstandard functions.
Since the hto[bl]e{16,32,64}() and [bl]e{16,32,64}toh() conversion
functions are nonstandard, add fallback definitions of these functions
to <isc/endian.h>, so that their unavailability does not prevent
compilation from succeeding.
Current versions of DragonFly BSD, FreeBSD, NetBSD, and OpenBSD all
support the modern variants of functions converting values between host
and big-endian/little-endian byte order while older ones might not.
Ensure <isc/endian.h> works properly in both cases.
Replace grep calls with awk scripts to more precisely detect presence of
CDS and CDNSKEY records in a signed zone file, in order to prevent rare
false positives for the "smartsign" system test triggered by the strings
"CDS" and/or "CDNSKEY" being accidentally present in the Base64 form of
DNSSEC-related data in the zone file being checked.
There's a small possibility of race between udp dispatcher and
socket code - socket code can still hold internal reference to a
socket while dispatcher calls isc_socket_open, which can cause
an assertion failure. Fix it by relaxing the assertion test, and
instead simply locking the socket in isc_socket_open.
qname minimization, even in relaxed mode, can fail on
some very broken domains. In relaxed mode, instead of
asking for "foo.bar NS" ask for "_.foo.bar A" to either
get a delegation or NXDOMAIN. It will require more queries
than regular mode for proper NXDOMAINs.
