feat(mdns): Add APIs for looking up self hosted services and getting the self hostname

components/mdns/include/mdns.h

@@ -128,6 +128,19 @@ void mdns_free(void);
  */
 esp_err_t mdns_hostname_set(const char *hostname);
 
+/**
+ * @brief Get the hostname for mDNS server
+ *
+ * @param hostname      pointer to the hostname, it should be allocated
+ *                      and hold at least MDNS_NAME_BUF_LEN chars
+ *
+ * @return
+ *     - ESP_OK success
+ *     - ESP_ERR_INVALID_ARG Parameter error
+ *     - ESP_ERR_INVALID_STATE when mdns is not initialized
+ */
+esp_err_t mdns_hostname_get(char *hostname);
+
 /**
  * @brief  Adds a hostname and address to be delegated
  *         A/AAAA queries will be replied for the hostname and
@@ -703,6 +716,24 @@ esp_err_t mdns_query_txt(const char *instance_name, const char *service_type, co
 esp_err_t mdns_lookup_delegated_service(const char *instance, const char *service_type, const char *proto, size_t max_results,
                                         mdns_result_t **result);
 
+/**
+ * @brief Look up self hosted services.
+ *
+ * @param  instance         instance name (NULL for uncertain instance)
+ * @param  service_type     service type (_http, _ftp, etc)
+ * @param  proto            service protocol (_tcp, _udp)
+ * @param  max_results      maximum results to be collected
+ * @param  result           pointer to the result of the search
+ *
+ * @return
+ *     - ESP_OK success
+ *     - ESP_ERR_INVALID_STATE  mDNS is not running
+ *     - ESP_ERR_NO_MEM         memory error
+ *     - ESP_ERR_INVALID_ARG    parameter error
+ */
+esp_err_t mdns_lookup_selfhosted_service(const char *instance, const char *service_type, const char *proto, size_t max_results,
+        mdns_result_t **result);
+
 /**
  * @brief  Query mDNS for A record
  *