From d7cfb7c7926c1c887d8ce5368fbe54289522057b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= <ondrej@isc.org>
Date: Wed, 12 Oct 2022 09:43:56 +0200
Subject: [PATCH] Retry on timeout in the UDP recv_one, recv_two and
 double_read tests

Since we are testing UDP on the localhost and the same interface, the
UDP datagrams can't get lost.  Change the connect read callback, so it
starts reading again on the timeout instead of just getting stuck, and
fail when any other result codes than ISC_R_SUCCESS and ISC_R_TIMEDOUT
are received because we don't expect them to happen in these simple
tests.
---
 tests/isc/udp_test.c | 59 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 58 insertions(+), 1 deletion(-)

diff --git a/tests/isc/udp_test.c b/tests/isc/udp_test.c
index c36074e304..1006caa4d1 100644
--- a/tests/isc/udp_test.c
+++ b/tests/isc/udp_test.c
@@ -806,6 +806,52 @@ udp__connect(void *arg __attribute__((__unused__))) {
 			  udp__connect_cb, NULL, T_CONNECT);
 }
 
+static void
+udp__connect_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
+		     isc_region_t *region, void *cbarg) {
+	uint64_t magic = 0;
+
+	assert_non_null(handle);
+
+	F();
+
+	switch (eresult) {
+	case ISC_R_TIMEDOUT:
+		/*
+		 * We are operating on the localhost, UDP cannot get lost, but
+		 * it could be delayed, so we read again until we get the
+		 * answer.
+		 */
+		isc_nm_read(handle, connect_readcb, cbarg);
+		return;
+	case ISC_R_SUCCESS:
+		assert_true(region->length >= sizeof(magic));
+
+		memmove(&magic, region->base, sizeof(magic));
+
+		assert_true(magic == send_magic);
+
+		if (have_expected_creads(atomic_fetch_add(&creads, 1) + 1)) {
+			do_creads_shutdown(loopmgr);
+		}
+
+		if (magic == send_magic && allow_send_back) {
+			connect_send(handle);
+			return;
+		}
+
+		break;
+	default:
+		fprintf(stderr, "%s(%p, %s, %p)\n", __func__, handle,
+			isc_result_totext(eresult), cbarg);
+		assert_int_equal(eresult, ISC_R_SUCCESS);
+	}
+
+	isc_refcount_decrement(&active_creads);
+
+	isc_nmhandle_detach(&handle);
+}
+
 static void
 udp__connect_cb(isc_nmhandle_t *handle, isc_result_t eresult, void *cbarg) {
 	isc_nmhandle_t *readhandle = NULL;
@@ -853,6 +899,8 @@ udp__connect_cb(isc_nmhandle_t *handle, isc_result_t eresult, void *cbarg) {
 ISC_SETUP_TEST_IMPL(udp_recv_one) {
 	setup_test(state);
 
+	connect_readcb = udp__connect_read_cb;
+
 	expected_cconnects = 1;
 	cconnects_shutdown = false;
 
@@ -892,6 +940,8 @@ ISC_LOOP_TEST_IMPL(udp_recv_one) {
 ISC_SETUP_TEST_IMPL(udp_recv_two) {
 	setup_test(state);
 
+	connect_readcb = udp__connect_read_cb;
+
 	expected_cconnects = 2;
 	cconnects_shutdown = false;
 
@@ -1044,6 +1094,14 @@ double_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 	F();
 
 	switch (eresult) {
+	case ISC_R_TIMEDOUT:
+		/*
+		 * We are operating on the localhost, UDP cannot get lost, but
+		 * it could be delayed, so we read again until we get the
+		 * answer.
+		 */
+		detach = false;
+		break;
 	case ISC_R_SUCCESS:
 		assert_true(region->length >= sizeof(magic));
 
@@ -1062,7 +1120,6 @@ double_read_cb(isc_nmhandle_t *handle, isc_result_t eresult,
 		}
 
 		break;
-	case ISC_R_TIMEDOUT:
 	case ISC_R_EOF:
 	case ISC_R_SHUTTINGDOWN:
 	case ISC_R_CANCELED: