bluetooth: tester: audio: Add NULL checks

- Add NULL checks for broadcast_source_stop
- Add NULL checks for broadcast_source_release
- Return -ESRCH if trying to stop ext_adv before creation

Signed-off-by: Alexander Svensen <alexander.svensen@nordicsemi.no>

tests/bluetooth/tester/src/audio/btp_cap.c

@@ -697,6 +697,11 @@ static uint8_t btp_cap_broadcast_source_release(const void *cmd, uint16_t cmd_le
 
 	LOG_DBG("");
 
+	/* If no source has been created yet, there is nothing to release */
+	if (source == NULL || source->cap_broadcast == NULL) {
+		return BTP_STATUS_SUCCESS;
+	}
+
 	err = bt_cap_initiator_broadcast_audio_delete(source->cap_broadcast);
 	if (err != 0) {
 		LOG_DBG("Unable to delete broadcast source: %d", err);
@@ -744,7 +749,11 @@ static uint8_t btp_cap_broadcast_adv_stop(const void *cmd, uint16_t cmd_len,
 	LOG_DBG("");
 
 	err = tester_gap_padv_stop();
-	if (err != 0) {
+	if (err == -ESRCH) {
+		/* Ext adv hasn't been created yet */
+		return BTP_STATUS_SUCCESS;
+	} else if (err != 0) {
+		LOG_DBG("Failed to stop periodic adv, err: %d", err);
 		return BTP_STATUS_FAILED;
 	}
 
@@ -786,6 +795,11 @@ static uint8_t btp_cap_broadcast_source_stop(const void *cmd, uint16_t cmd_len,
 	struct btp_bap_broadcast_local_source *source =
 		btp_bap_broadcast_local_source_get(cp->source_id);
 
+	/* If no source has been started yet, there is nothing to stop */
+	if (source == NULL || source->cap_broadcast == NULL) {
+		return BTP_STATUS_SUCCESS;
+	}
+
 	err = bt_cap_initiator_broadcast_audio_stop(source->cap_broadcast);
 	if (err != 0) {
 		LOG_ERR("Failed to stop audio source: %d", err);

tests/bluetooth/tester/src/btp_gap.c

@@ -1548,7 +1548,8 @@ int tester_gap_padv_stop(void)
 	int err;
 
 	if (ext_adv == NULL) {
-		return -EINVAL;
+		/* Ext adv not yet created */
+		return -ESRCH;
 	}
 
 	/* Enable Periodic Advertising */