For BIND 9.16+, TLS aware compiler is required, and using
ISC_THREAD_LOCAL is preferred way of using Thread Local Storage. The
isc_thread_key API is no longer used anywhere and hence was removed from
BIND 9.
The new ISC_THREAD_LOCAL macro unifies usage of platform dependent
Thread Local Storage definition thread_local vs __thread vs
__declspec(thread) to a single macro.
The commit also unifies the required level of support for TLS as for
some parts of the code it was mandatory and for some parts of the code
it wasn't.
This is a replacement for the existing isc_socket and isc_socketmgr
implementation. It uses libuv for asynchronous network communication;
"networker" objects will be distributed across worker threads reading
incoming packets and sending them for processing.
UDP listener sockets automatically create an array of "child" sockets
so each worker can listen separately.
TCP sockets are shared amongst worker threads.
A TCPDNS socket is a wrapper around a TCP socket, which handles the
the two-byte length field at the beginning of DNS messages over TCP.
(Other wrapper socket types can be implemented in the future to handle
DNS over TLS, DNS over HTTPS, etc.)
Previously isc_thread_join() would return ISC_R_UNEXPECTED on a failure to
create new thread. All such occurences were caught and wrapped into assert
function at higher level. The function was simplified to assert directly in the
isc_thread_join() function and all caller level assertions were removed.
Previously isc_thread_create() would return ISC_R_UNEXPECTED on a failure to
create new thread. All such occurences were caught and wrapped into assert
function at higher level. The function was simplified to assert directly in the
isc_thread_create() function and all caller level assertions were removed.
Commit b104a9bc50 introduced unconditional
use of the ATOMIC_VAR_INIT() macro in bin/dnssec/dnssec-signzone.c even
though that macro is only defined on Unix platforms. Define it on
Windows systems as well in order to prevent build failures.