add a netmgr unit test

tests of UDP and TCP cases including:
- sending and receiving
- closure sockets without reading or sending
- closure of sockets at various points while sending and receiving
- since the teste is multithreaded, cmocka now aborts tests on the
  first failure, so that failures in subthreads are caught and
  reported correctly.

.gitlab-ci.yml

@@ -39,6 +39,9 @@ variables:
 
   BIND_INSTALL_PATH: "${CI_PROJECT_DIR}/.local"
 
+  # In multithreaded unit tests, abort on the first failure
+  CMOCKA_TEST_ABORT: 1
+
 stages:
   - autoconf
   - precheck

lib/isc/tests/Makefile.am

@@ -29,6 +29,7 @@ check_PROGRAMS =	\
 	md_test		\
 	mem_test	\
 	netaddr_test	\
+	netmgr_test \
 	parse_test	\
 	pool_test	\
 	quota_test	\
@@ -68,6 +69,14 @@ random_test_LDADD =	\
 	$(LDADD)	\
 	-lm
 
+netmgr_test_CPPFLAGS =	\
+	$(AM_CPPFLAGS)	\
+	$(LIBUV_CFLAGS)
+
+netmgr_test_LDADD =	\
+	$(LDADD)	\
+	$(LIBUV_LIBS)
+
 unit-local: check
 
 EXTRA_DIST = testdata

util/copyrights

@@ -1938,6 +1938,7 @@
 ./lib/isc/tests/md_test.c			C	2018,2019,2020
 ./lib/isc/tests/mem_test.c			C	2015,2016,2017,2018,2019,2020
 ./lib/isc/tests/netaddr_test.c			C	2016,2018,2019,2020
+./lib/isc/tests/netmgr_test.c			C	2020
 ./lib/isc/tests/parse_test.c			C	2012,2013,2016,2018,2019,2020
 ./lib/isc/tests/pool_test.c			C	2013,2016,2018,2019,2020
 ./lib/isc/tests/quota_test.c			C	2020