net: lib: coap: Add packet pointer to client response callback data

Pass a pointer to the CoAP packet in the response data. This allows
callback function to inspect for CoAP options.

Signed-off-by: Pieter De Gendt <pieter.degendt@basalte.be>

Author: pdgendt

include/zephyr/net/coap_client.h

@@ -41,6 +41,8 @@ struct coap_client_response_data {
 	 * @ref coap_response_code for positive.
 	 */
 	int16_t result_code;
+	/** A pointer to the response CoAP packet. NULL for error result. */
+	const struct coap_packet *packet;
 	/** Payload offset from the beginning of a blockwise transfer. */
 	size_t offset;
 	/** Buffer containing the payload from the response. NULL for empty payload. */

subsys/net/lib/coap/coap_client.c

@@ -956,6 +956,7 @@ static int handle_response(struct coap_client *client, const struct coap_packet
 		if (!atomic_set(&internal_req->in_callback, 1)) {
 			const struct coap_client_response_data resp_data = {
 				.result_code = response_code,
+				.packet = response,
 				.offset = internal_req->offset,
 				.payload = payload,
 				.payload_len = payload_len,