1 files changed, 52 insertions, 22 deletions

diff --git a/main/mdns_service.c b/main/mdns_service.c
index 761ade5..d389161 100644
--- a/main/mdns_service.c
+++ b/main/mdns_service.c
@@ -14,52 +14,82 @@ static const char *SERVICE   = "_scrypted-viewport";
 static const char *PROTO     = "_tcp";
 static const uint16_t PORT   = 80;
 
-static esp_err_t apply_records(void)
+// Pull the current hostname + TXT values from viewport_state under the lock.
+static void snapshot_state(char *hostname, size_t host_cap,
+                           const char **resolution,
+                           const char **orientation,
+                           char *name, size_t name_cap)
 {
     viewport_state_lock();
     viewport_state_t *st = viewport_state_get();
 
-    char hostname[80];
     if (st->viewport_name[0]) {
-        snprintf(hostname, sizeof(hostname), "viewport-%s", st->viewport_name);
+        snprintf(hostname, host_cap, "viewport-%s", st->viewport_name);
     } else {
-        snprintf(hostname, sizeof(hostname), "viewport");
+        snprintf(hostname, host_cap, "viewport");
     }
-
-    const char *resolution  = viewport_state_resolution_str();
-    const char *orientation = (st->orientation == VIEWPORT_ORIENTATION_PORTRAIT)
-                                  ? "portrait" : "landscape";
-    const char *name_value  = st->viewport_name[0] ? st->viewport_name : "";
+    *resolution  = viewport_state_resolution_str();
+    *orientation = (st->orientation == VIEWPORT_ORIENTATION_PORTRAIT)
+                       ? "portrait" : "landscape";
+    snprintf(name, name_cap, "%s", st->viewport_name[0] ? st->viewport_name : "");
 
     viewport_state_unlock();
+}
+
+static esp_err_t apply_hostname(void)
+{
+    char hostname[80];
+    const char *resolution, *orientation;
+    char name[64];
+    snapshot_state(hostname, sizeof(hostname),
+                   &resolution, &orientation,
+                   name, sizeof(name));
+    return mdns_hostname_set(hostname);
+}
+
+static esp_err_t apply_txt(void)
+{
+    char hostname[80];
+    const char *resolution, *orientation;
+    char name[64];
+    snapshot_state(hostname, sizeof(hostname),
+                   &resolution, &orientation,
+                   name, sizeof(name));
 
     mdns_txt_item_t txt[] = {
         { "version",     VIEWPORT_VERSION },
         { "resolution",  resolution },
         { "orientation", orientation },
-        { "name",        name_value },
+        { "name",        name },
     };
-    const size_t txt_count = sizeof(txt) / sizeof(txt[0]);
-
-    ESP_RETURN_ON_ERROR(mdns_hostname_set(hostname), TAG, "hostname_set");
-    ESP_RETURN_ON_ERROR(mdns_service_txt_set(SERVICE, PROTO, txt, txt_count),
-                       TAG, "txt_set");
-
-    ESP_LOGI(TAG, "advertising %s.local on %s.%s.local:%u",
-             hostname, SERVICE, PROTO, PORT);
-    return ESP_OK;
+    return mdns_service_txt_set(SERVICE, PROTO, txt,
+                                sizeof(txt) / sizeof(txt[0]));
 }
 
 esp_err_t mdns_service_start(void)
 {
-    ESP_RETURN_ON_ERROR(mdns_init(), TAG, "mdns_init");
+    // Order matters: mdns_service_add() rejects with INVALID_ARG if the
+    // hostname isn't set yet. So: init -> hostname -> service_add -> TXT.
+    ESP_RETURN_ON_ERROR(mdns_init(),           TAG, "mdns_init");
+    ESP_RETURN_ON_ERROR(apply_hostname(),       TAG, "hostname_set");
     ESP_RETURN_ON_ERROR(
         mdns_service_add(NULL, SERVICE, PROTO, PORT, NULL, 0),
         TAG, "service_add");
-    return apply_records();
+    ESP_RETURN_ON_ERROR(apply_txt(),            TAG, "txt_set");
+
+    char hostname[80];
+    const char *resolution, *orientation;
+    char name[64];
+    snapshot_state(hostname, sizeof(hostname),
+                   &resolution, &orientation,
+                   name, sizeof(name));
+    ESP_LOGI(TAG, "mDNS up — %s.local advertising %s.%s.local on :%u",
+             hostname, SERVICE, PROTO, PORT);
+    return ESP_OK;
 }
 
 esp_err_t mdns_service_refresh(void)
 {
-    return apply_records();
+    ESP_RETURN_ON_ERROR(apply_hostname(), TAG, "hostname_set");
+    return apply_txt();
 }