From 2355f4bb2487162bbd4e6c5ae05f710415f88d3e Mon Sep 17 00:00:00 2001
From: Abdellatif IDIRY <aidiry@dream.fr>
Date: Mon, 25 Oct 2021 10:45:22 +0200
Subject: [PATCH] mdns : Add mdns_build_subtype_service_domain() function that
 build a domain name of subtype service

---
 src/apps/mdns/mdns_domain.c         | 26 ++++++++++++++++++++++++++
 src/include/lwip/apps/mdns.h        |  2 +-
 src/include/lwip/apps/mdns_domain.h |  2 +-
 3 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/src/apps/mdns/mdns_domain.c b/src/apps/mdns/mdns_domain.c
index 265b5e6a..1839ee2b 100644
--- a/src/apps/mdns/mdns_domain.c
+++ b/src/apps/mdns/mdns_domain.c
@@ -632,4 +632,30 @@ mdns_write_domain(struct mdns_outpacket *outpkt, struct mdns_domain *domain)
   return ERR_OK;
 }
 
+/**
+ * Build domain name for a subtype service
+ * @param domain Where to write the domain name
+ * @param service The service struct, containing service name, type and protocol
+ * @param include_name Whether to include the service name in the domain
+ * @return ERR_OK if domain was written. If service name is included,
+ *         \<subType\>.\<_sub\>.\<type\>.\<proto\>.local. will be written, otherwise \<type\>.\<proto\>.local.
+ *         An err_t is returned on error.
+ */
+err_t
+mdns_build_subtype_service_domain(struct mdns_domain *domain, struct mdns_service *service, int subTypes_index)
+{
+  err_t res;
+  LWIP_UNUSED_ARG(res);
+  memset(domain, 0, sizeof(struct mdns_domain));
+  res = mdns_domain_add_label(domain, service->subTypes[subTypes_index], strlen(service->subTypes[subTypes_index]));
+  LWIP_ERROR("mdns_build_service_domain: Failed to add label", (res == ERR_OK), return res);
+  res = mdns_domain_add_label(domain, "_sub", 4);
+  LWIP_ERROR("mdns_build_service_domain: Failed to add label", (res == ERR_OK), return res);
+  res = mdns_domain_add_label(domain, service->service, (u8_t)strlen(service->service));
+  LWIP_ERROR("mdns_build_service_domain: Failed to add label", (res == ERR_OK), return res);
+  res = mdns_domain_add_label(domain, dnssd_protos[service->proto], (u8_t)strlen(dnssd_protos[service->proto]));
+  LWIP_ERROR("mdns_build_service_domain: Failed to add label", (res == ERR_OK), return res);
+  return mdns_add_dotlocal(domain);
+}
+
 #endif /* LWIP_MDNS_RESPONDER */
diff --git a/src/include/lwip/apps/mdns.h b/src/include/lwip/apps/mdns.h
index 6c9648b6..9480415d 100644
--- a/src/include/lwip/apps/mdns.h
+++ b/src/include/lwip/apps/mdns.h
@@ -112,7 +112,7 @@ err_t mdns_resp_remove_netif(struct netif *netif);
 err_t mdns_resp_rename_netif(struct netif *netif, const char *hostname);
 int mdns_resp_netif_active(struct netif *netif);
 
-s8_t  mdns_resp_add_service(struct netif *netif, const char *name, const char *service, enum mdns_sd_proto proto, u16_t port, service_get_txt_fn_t txt_fn, void *txt_data, char **subTypes,  u8_t subtypes_nbr )
+s8_t  mdns_resp_add_service(struct netif *netif, const char *name, const char *service, enum mdns_sd_proto proto, u16_t port, service_get_txt_fn_t txt_fn, void *txt_data, char **subTypes,  u8_t subtypes_nbr );
 err_t mdns_resp_del_service(struct netif *netif, u8_t slot);
 err_t mdns_resp_rename_service(struct netif *netif, u8_t slot, const char *name);
 
diff --git a/src/include/lwip/apps/mdns_domain.h b/src/include/lwip/apps/mdns_domain.h
index 9fa804e6..140029b3 100644
--- a/src/include/lwip/apps/mdns_domain.h
+++ b/src/include/lwip/apps/mdns_domain.h
@@ -70,7 +70,7 @@ err_t mdns_build_request_domain(struct mdns_domain *domain, struct mdns_request
 #endif
 u16_t mdns_compress_domain(struct pbuf *pbuf, u16_t *offset, struct mdns_domain *domain);
 err_t mdns_write_domain(struct mdns_outpacket *outpkt, struct mdns_domain *domain);
-
+err_t mdns_build_subtype_service_domain(struct mdns_domain *domain, struct mdns_service *service, int subTypes_index);
 #endif /* LWIP_MDNS_RESPONDER */
 
 #ifdef __cplusplus