Improve the udp_shutdown_read and udp_cancel_read tests

In the udp_shutdown_read unit test, delay the isc_loopmgr_shutdown() to
the send callback, and in the udp_cancel_read test wait for a single
timed out test, then read again, send an UDP packet and cancel the read
from the send callback.

tests/isc/udp_test.c

@@ -306,7 +306,6 @@ udp_noresponse_recv_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 static void
 udp_noresponse_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 		       isc_region_t *region, void *cbarg) {
-	UNUSED(handle);
 	UNUSED(region);
 	UNUSED(cbarg);
 
@@ -339,9 +338,6 @@ udp_noresponse_connect_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 	isc_nmhandle_t *readhandle = NULL;
 	isc_nmhandle_t *sendhandle = NULL;
 
-	UNUSED(handle);
-	UNUSED(cbarg);
-
 	isc_refcount_decrement(&active_cconnects);
 
 	assert_int_equal(eresult, ISC_R_SUCCESS);
@@ -463,8 +459,6 @@ udp_timeout_recovery_connect_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 	isc_nmhandle_t *readhandle = NULL;
 	isc_nmhandle_t *sendhandle = NULL;
 
-	UNUSED(cbarg);
-
 	F();
 
 	isc_refcount_decrement(&active_cconnects);
@@ -557,14 +551,50 @@ ISC_LOOP_TEST_IMPL(udp_shutdown_connect) {
 	isc_job_run(loopmgr, udp_connect_udpconnect, netmgr);
 }
 
+static void
+udp_shutdown_read_recv_cb(isc_nmhandle_t *handle, isc_result_t eresult,
+			  isc_region_t *region, void *cbarg) {
+	uint64_t magic = 0;
+
+	UNUSED(cbarg);
+
+	assert_non_null(handle);
+
+	F();
+
+	assert_int_equal(eresult, ISC_R_SUCCESS);
+
+	assert_true(region->length == sizeof(magic));
+
+	memmove(&magic, region->base, sizeof(magic));
+	assert_true(magic == send_magic);
+}
+
+static void
+udp_shutdown_read_send_cb(isc_nmhandle_t *handle, isc_result_t eresult,
+			  void *cbarg) {
+	UNUSED(cbarg);
+
+	F();
+
+	assert_non_null(handle);
+	assert_int_equal(eresult, ISC_R_SUCCESS);
+
+	atomic_fetch_add(&csends, 1);
+
+	isc_loopmgr_shutdown(loopmgr);
+
+	isc_nmhandle_detach(&handle);
+	isc_refcount_decrement(&active_csends);
+}
+
 static void
 udp_shutdown_read_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 			  isc_region_t *region, void *cbarg) {
-	UNUSED(handle);
 	UNUSED(region);
 	UNUSED(cbarg);
 
-	assert_int_equal(eresult, ISC_R_SHUTTINGDOWN);
+	assert_true(eresult == ISC_R_SHUTTINGDOWN || eresult == ISC_R_TIMEDOUT);
 
 	isc_refcount_decrement(&active_creads);
 
@@ -577,21 +607,25 @@ static void
 udp_shutdown_read_connect_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 			     void *cbarg) {
 	isc_nmhandle_t *readhandle = NULL;
-
+	isc_nmhandle_t *sendhandle = NULL;
-	UNUSED(handle);
-	UNUSED(cbarg);
 
 	isc_refcount_decrement(&active_cconnects);
 
 	assert_int_equal(eresult, ISC_R_SUCCESS);
 
+	/* Read */
 	isc_refcount_increment0(&active_creads);
 	isc_nmhandle_attach(handle, &readhandle);
 	isc_nm_read(handle, udp_shutdown_read_read_cb, cbarg);
 
-	atomic_fetch_add(&cconnects, 1);
+	/* Send */
+	isc_refcount_increment0(&active_csends);
+	isc_nmhandle_attach(handle, &sendhandle);
+	isc_nmhandle_setwritetimeout(handle, T_IDLE);
+	isc_nm_send(sendhandle, (isc_region_t *)&send_msg,
+		    udp_shutdown_read_send_cb, cbarg);
 
-	isc_loopmgr_shutdown(loopmgr);
+	atomic_fetch_add(&cconnects, 1);
 }
 
 ISC_SETUP_TEST_IMPL(udp_shutdown_read) {
@@ -609,6 +643,8 @@ ISC_TEARDOWN_TEST_IMPL(udp_shutdown_read) {
 }
 
 ISC_LOOP_TEST_IMPL(udp_shutdown_read) {
+	start_listening(ISC_NM_LISTEN_ONE, udp_shutdown_read_recv_cb);
+
 	isc_refcount_increment0(&active_cconnects);
 	isc_nm_udpconnect(netmgr, &udp_connect_addr, &udp_listen_addr,
 			  udp_shutdown_read_connect_cb, NULL, T_SOFT);
@@ -618,7 +654,8 @@ static void
 udp_cancel_read_recv_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 			isc_region_t *region, void *cbarg) {
 	uint64_t magic = 0;
-	isc_nmhandle_t *sendhandle = NULL;
+
+	UNUSED(cbarg);
 
 	assert_non_null(handle);
 
@@ -630,38 +667,6 @@ udp_cancel_read_recv_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 
 	memmove(&magic, region->base, sizeof(magic));
 	assert_true(magic == send_magic);
-
-	isc_nmhandle_attach(handle, &sendhandle);
-	isc_refcount_increment0(&active_ssends);
-	isc_nmhandle_setwritetimeout(sendhandle, T_IDLE);
-	isc_nm_send(sendhandle, (isc_region_t *)&send_msg, listen_send_cb,
-		    cbarg);
-}
-
-static void
-udp_cancel_read_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
-			isc_region_t *region, void *cbarg) {
-	UNUSED(handle);
-	UNUSED(region);
-	UNUSED(cbarg);
-
-	F();
-
-	switch (eresult) {
-	case ISC_R_TIMEDOUT:
-	case ISC_R_EOF:
-		break;
-	default:
-		UNREACHABLE();
-	}
-
-	isc_refcount_decrement(&active_creads);
-
-	atomic_fetch_add(&creads, 1);
-
-	isc_nmhandle_detach(&handle);
-
-	isc_loopmgr_shutdown(loopmgr);
 }
 
 static void
@@ -676,18 +681,56 @@ udp_cancel_read_send_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 
 	atomic_fetch_add(&csends, 1);
 
+	isc_nm_cancelread(handle);
+
 	isc_nmhandle_detach(&handle);
 	isc_refcount_decrement(&active_csends);
 }
 
+static void
+udp_cancel_read_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
+			isc_region_t *region, void *cbarg) {
+	isc_nmhandle_t *sendhandle = NULL;
+	isc_nmhandle_t *readhandle = NULL;
+
+	UNUSED(region);
+
+	F();
+
+	switch (eresult) {
+	case ISC_R_TIMEDOUT:
+
+		/* Read again */
+		isc_refcount_increment0(&active_creads);
+		isc_nmhandle_attach(handle, &readhandle);
+		isc_nm_read(handle, udp_cancel_read_read_cb, cbarg);
+
+		/* Send */
+		isc_refcount_increment0(&active_csends);
+		isc_nmhandle_attach(handle, &sendhandle);
+		isc_nmhandle_setwritetimeout(handle, T_IDLE);
+		isc_nm_send(sendhandle, (isc_region_t *)&send_msg,
+			    udp_cancel_read_send_cb, cbarg);
+		break;
+	case ISC_R_EOF:
+		/* The read has been canceled */
+		isc_loopmgr_shutdown(loopmgr);
+		break;
+	default:
+		UNREACHABLE();
+	}
+
+	isc_refcount_decrement(&active_creads);
+
+	atomic_fetch_add(&creads, 1);
+
+	isc_nmhandle_detach(&handle);
+}
+
 static void
 udp_cancel_read_connect_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 			   void *cbarg) {
 	isc_nmhandle_t *readhandle = NULL;
-	isc_nmhandle_t *sendhandle = NULL;
-
-	UNUSED(handle);
-	UNUSED(cbarg);
 
 	isc_refcount_decrement(&active_cconnects);
 
@@ -697,22 +740,13 @@ udp_cancel_read_connect_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 	isc_nmhandle_attach(handle, &readhandle);
 	isc_nm_read(handle, udp_cancel_read_read_cb, cbarg);
 
-	/* Send */
-	isc_refcount_increment0(&active_csends);
-	isc_nmhandle_attach(handle, &sendhandle);
-	isc_nmhandle_setwritetimeout(handle, T_IDLE);
-	isc_nm_send(sendhandle, (isc_region_t *)&send_msg,
-		    udp_cancel_read_send_cb, readhandle);
-
-	isc_nm_cancelread(readhandle);
-
 	atomic_fetch_add(&cconnects, 1);
 }
 
 ISC_SETUP_TEST_IMPL(udp_cancel_read) {
 	setup_test(state);
 	expected_cconnects = 1;
-	expected_creads = 1;
+	expected_creads = 2;
 	return (0);
 }
 
@@ -735,8 +769,6 @@ static void
 udp__send_cb(isc_nmhandle_t *handle, isc_result_t eresult, void *cbarg) {
 	isc_nmhandle_t *sendhandle = handle;
 
-	UNUSED(cbarg);
-
 	assert_non_null(sendhandle);
 
 	F();
@@ -782,8 +814,6 @@ udp__connect_cb(isc_nmhandle_t *handle, isc_result_t eresult, void *cbarg) {
 	isc_nmhandle_t *readhandle = NULL;
 	isc_nmhandle_t *sendhandle = NULL;
 
-	UNUSED(cbarg);
-
 	F();
 
 	isc_refcount_decrement(&active_cconnects);
@@ -935,9 +965,6 @@ ISC_LOOP_TEST_IMPL(udp_recv_send) {
 
 static void
 double_read_send_cb(isc_nmhandle_t *handle, isc_result_t eresult, void *cbarg) {
-	UNUSED(cbarg);
-	UNUSED(eresult);
-
 	assert_non_null(handle);
 
 	F();
@@ -1015,8 +1042,6 @@ double_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 	uint64_t magic = 0;
 	bool detach = false;
 
-	UNUSED(cbarg);
-
 	assert_non_null(handle);
 
 	F();