tests: net: coap: add test for age wrap around

- Added a test to the CoAP testsuite for age wrap around
- Added test for `coap_age_is_newer`

Signed-off-by: Sibert Declercq <[email protected]>

tests/net/lib/coap/src/main.c

@@ -39,18 +39,25 @@ bool _coap_match_path_uri(const char * const *path,
 			  const char *uri, uint16_t len);
 
 /* Some forward declarations */
-static void server_notify_callback(struct coap_resource *resource,
-				   struct coap_observer *observer);
+static void server_resource_1_callback(struct coap_resource *resource,
+				       struct coap_observer *observer);
+
+static void server_resource_2_callback(struct coap_resource *resource,
+				       struct coap_observer *observer);
 
 static int server_resource_1_get(struct coap_resource *resource,
 				 struct coap_packet *request,
 				 struct sockaddr *addr, socklen_t addr_len);
 
 static const char * const server_resource_1_path[] = { "s", "1", NULL };
-static struct coap_resource server_resources[] =  {
+static const char *const server_resource_2_path[] = { "s", "2", NULL };
+static struct coap_resource server_resources[] = {
 	{ .path = server_resource_1_path,
 	  .get = server_resource_1_get,
-	  .notify = server_notify_callback },
+	  .notify = server_resource_1_callback },
+	{ .path = server_resource_2_path,
+	  .get = server_resource_1_get, /* Get can be shared with the first resource */
+	  .notify = server_resource_2_callback },
 	{ },
 };
 
@@ -63,6 +70,12 @@ static struct sockaddr_in6 dummy_addr = {
 
 static uint8_t data_buf[2][COAP_BUF_SIZE];
 
+#define COAP_ROLLOVER_AGE (1 << 23)
+#define COAP_MAX_AGE      0xffffff
+#define COAP_FIRST_AGE    2
+
+extern bool coap_age_is_newer(int v1, int v2);
+
 ZTEST(coap, test_build_empty_pdu)
 {
 	uint8_t result_pdu[] = { 0x40, 0x01, 0x0, 0x0 };
@@ -822,8 +835,8 @@ static bool ipaddr_cmp(const struct sockaddr *a, const struct sockaddr *b)
 	return false;
 }
 
-static void server_notify_callback(struct coap_resource *resource,
-				   struct coap_observer *observer)
+static void server_resource_1_callback(struct coap_resource *resource,
+				       struct coap_observer *observer)
 {
 	bool r;
 
@@ -832,6 +845,14 @@ static void server_notify_callback(struct coap_resource *resource,
 
 	coap_remove_observer(resource, observer);
 }
+static void server_resource_2_callback(struct coap_resource *resource,
+				       struct coap_observer *observer)
+{
+	bool r;
+
+	r = ipaddr_cmp(&observer->addr, (const struct sockaddr *)&dummy_addr);
+	zassert_true(r, "The address of the observer doesn't match");
+}
 
 static int server_resource_1_get(struct coap_resource *resource,
 				 struct coap_packet *request,
@@ -891,7 +912,7 @@ ZTEST(coap, test_observer_server)
 		0x45, 0x01, 0x12, 0x34,
 		't', 'o', 'k', 'e', 'n',
 		0x60, /* enable observe option */
-		0x51, 's', 0x01, '2', /* path */
+		0x51, 's', 0x01, '3', /* path */
 	};
 	struct coap_packet req;
 	struct coap_option options[4] = {};
@@ -1771,4 +1792,61 @@ ZTEST(coap, test_transmission_parameters)
 	zassert_equal(pending->params.max_retransmission, 2, "Wrong max retransmission value");
 }
 
+ZTEST(coap, test_notify_age)
+{
+	uint8_t valid_request_pdu[] = {
+		0x45, 0x01, 0x12, 0x34, 't', 'o', 'k', 'e', 'n', 0x60, /* enable observe option */
+		0x51, 's',  0x01, '2',                                 /* path */
+	};
+
+	struct coap_packet req;
+	struct coap_option options[4] = {};
+	uint8_t *data = data_buf[0];
+	uint8_t opt_num = ARRAY_SIZE(options) - 1;
+	struct coap_resource *resource = &server_resources[1];
+	int r;
+	struct coap_observer *observer;
+	int last_age;
+
+	memcpy(data, valid_request_pdu, sizeof(valid_request_pdu));
+
+	r = coap_packet_parse(&req, data, sizeof(valid_request_pdu), options, opt_num);
+	zassert_equal(r, 0, "Could not initialize packet");
+
+	r = coap_handle_request(&req, server_resources, options, opt_num,
+				(struct sockaddr *)&dummy_addr, sizeof(dummy_addr));
+	zassert_equal(r, 0, "Could not handle packet");
+
+	/* Forward time a bit, as not to run this 8 million time */
+	resource->age = COAP_OBSERVE_MAX_AGE - 10;
+
+	last_age = resource->age;
+
+	for (int i = 0; i < 15; i++) {
+		r = coap_resource_notify(resource);
+		zassert_true(coap_age_is_newer(last_age, resource->age),
+			     "Resource age expected to be newer");
+		last_age = resource->age;
+	}
+
+	observer =
+		CONTAINER_OF(sys_slist_peek_head(&resource->observers), struct coap_observer, list);
+	coap_remove_observer(resource, observer);
+}
+
+ZTEST(coap, test_age_is_newer)
+{
+	for (int i = COAP_FIRST_AGE; i < COAP_MAX_AGE; ++i) {
+		zassert_true(coap_age_is_newer(i, i + 1),
+			     "Resource age expected to be marked as newer");
+	}
+
+	zassert_true(coap_age_is_newer(COAP_MAX_AGE, COAP_FIRST_AGE),
+		     "First age should be marked as newer");
+	zassert_true(coap_age_is_newer(COAP_FIRST_AGE, COAP_ROLLOVER_AGE),
+		     "Rollover age should be marked as newer");
+	zassert_true(coap_age_is_newer(COAP_ROLLOVER_AGE, COAP_MAX_AGE),
+		     "Max age should be marked as newer");
+}
+
 ZTEST_SUITE(coap, NULL, NULL, NULL, NULL, NULL);