From f6004fc43165439050478ae17c336b1f11cbd0b1 Mon Sep 17 00:00:00 2001
From: Seppo Takalo <seppo.takalo@nordicsemi.no>
Date: Mon, 18 Nov 2024 15:47:01 +0200
Subject: [PATCH] [nrf fromtree] net: lib: coap_client: Release non-confirmable
 requests

Non-confirmable CoAP requests need lifetime tracking as well
so we can free the structure after a timeout.

Signed-off-by: Seppo Takalo <seppo.takalo@nordicsemi.no>
(cherry picked from commit 2066cf6a3d17fc1a1733fab3e47fe8969145df6b)
---
 subsys/net/lib/coap/coap_client.c | 53 ++++++++++++++++++++-----------
 1 file changed, 35 insertions(+), 18 deletions(-)

diff --git a/subsys/net/lib/coap/coap_client.c b/subsys/net/lib/coap/coap_client.c
index 30dcbb42005..a3c56281819 100644
--- a/subsys/net/lib/coap/coap_client.c
+++ b/subsys/net/lib/coap/coap_client.c
@@ -105,6 +105,10 @@ static bool exchange_lifetime_exceeded(struct coap_client_internal_request *inte
 		return true;
 	}
 
+	if (internal_req->pending.t0 == 0) {
+		return true;
+	}
+
 	time_since_t0 = k_uptime_get() - internal_req->pending.t0;
 	exchange_lifetime =
 		(internal_req->pending.params.ack_timeout * COAP_EXCHANGE_LIFETIME_FACTOR);
@@ -364,7 +368,7 @@ int coap_client_req(struct coap_client *client, int sock, const struct sockaddr
 	/* Don't allow changing to a different socket if there is already request ongoing. */
 	if (client->fd != sock && has_ongoing_request(client)) {
 		ret = -EALREADY;
-		goto out;
+		goto release;
 	}
 
 	/* Don't allow changing to a different address if there is already request ongoing. */
@@ -373,7 +377,7 @@ int coap_client_req(struct coap_client *client, int sock, const struct sockaddr
 			if (has_ongoing_request(client)) {
 				LOG_WRN("Can't change to a different socket, request ongoing.");
 				ret = -EALREADY;
-				goto out;
+				goto release;
 			}
 
 			memcpy(&client->address, addr, sizeof(*addr));
@@ -384,7 +388,7 @@ int coap_client_req(struct coap_client *client, int sock, const struct sockaddr
 			if (has_ongoing_request(client)) {
 				LOG_WRN("Can't change to a different socket, request ongoing.");
 				ret = -EALREADY;
-				goto out;
+				goto release;
 			}
 
 			memset(&client->address, 0, sizeof(client->address));
@@ -397,7 +401,7 @@ int coap_client_req(struct coap_client *client, int sock, const struct sockaddr
 	ret = coap_client_init_request(client, req, internal_req, false);
 	if (ret < 0) {
 		LOG_ERR("Failed to initialize coap request");
-		goto out;
+		goto release;
 	}
 
 	if (client->send_echo) {
@@ -405,7 +409,7 @@ int coap_client_req(struct coap_client *client, int sock, const struct sockaddr
 						client->echo_option.value, client->echo_option.len);
 		if (ret < 0) {
 			LOG_ERR("Failed to append echo option");
-			goto out;
+			goto release;
 		}
 		client->send_echo = false;
 	}
@@ -413,28 +417,36 @@ int coap_client_req(struct coap_client *client, int sock, const struct sockaddr
 	ret = coap_client_schedule_poll(client, sock, req, internal_req);
 	if (ret < 0) {
 		LOG_ERR("Failed to schedule polling");
-		goto out;
+		goto release;
 	}
 
-	/* only TYPE_CON messages need pending tracking */
-	if (coap_header_get_type(&internal_req->request) == COAP_TYPE_CON) {
-		ret = coap_pending_init(&internal_req->pending, &internal_req->request,
-					&client->address, params);
+	ret = coap_pending_init(&internal_req->pending, &internal_req->request,
+				&client->address, params);
 
-		if (ret < 0) {
-			LOG_ERR("Failed to initialize pending struct");
-			goto out;
-		}
+	if (ret < 0) {
+		LOG_ERR("Failed to initialize pending struct");
+		goto release;
+	}
 
-		coap_pending_cycle(&internal_req->pending);
-		internal_req->is_observe = coap_request_is_observe(&internal_req->request);
-		LOG_DBG("Request is_observe %d", internal_req->is_observe);
+	/* Non-Confirmable messages are not retried, but we still track the lifetime as
+	 * replies are acceptable.
+	 */
+	if (coap_header_get_type(&internal_req->request) == COAP_TYPE_NON_CON) {
+		internal_req->pending.retries = 0;
 	}
+	coap_pending_cycle(&internal_req->pending);
+	internal_req->is_observe = coap_request_is_observe(&internal_req->request);
+	LOG_DBG("Request is_observe %d", internal_req->is_observe);
 
 	ret = send_request(sock, internal_req->request.data, internal_req->request.offset, 0,
 			  &client->address, client->socklen);
 	if (ret < 0) {
-		LOG_ERR("Transmission failed: %d", errno);
+		ret = -errno;
+	}
+
+release:
+	if (ret < 0) {
+		LOG_ERR("Failed to send request: %d", ret);
 		reset_internal_request(internal_req);
 	} else {
 		/* Do not return the number of bytes sent */
@@ -521,6 +533,11 @@ static void coap_client_resend_handler(struct coap_client *client)
 
 	for (int i = 0; i < CONFIG_COAP_CLIENT_MAX_REQUESTS; i++) {
 		if (timeout_expired(&client->requests[i])) {
+			if (!client->requests[i].coap_request.confirmable) {
+				release_internal_request(&client->requests[i]);
+				continue;
+			}
+
 			ret = resend_request(client, &client->requests[i]);
 			if (ret < 0) {
 				report_callback_error(&client->requests[i], ret);