[mdns] Modernize to C++17 nested namespace syntax

esphome/components/api/api_frame_helper.h

@@ -84,7 +84,9 @@ class APIFrameHelper {
  public:
   APIFrameHelper() = default;
   explicit APIFrameHelper(std::unique_ptr<socket::Socket> socket, const ClientInfo *client_info)
-      : socket_(std::move(socket)), client_info_(client_info) {}
+      : socket_owned_(std::move(socket)), client_info_(client_info) {
+    socket_ = socket_owned_.get();
+  }
   virtual ~APIFrameHelper() = default;
   virtual APIError init() = 0;
   virtual APIError loop();
@@ -147,8 +149,9 @@ class APIFrameHelper {
   APIError write_raw_(const struct iovec *iov, int iovcnt, socket::Socket *socket, std::vector<uint8_t> &tx_buf,
                       const std::string &info, StateEnum &state, StateEnum failed_state);
 
-  // Socket ownership (4 bytes on 32-bit, 8 bytes on 64-bit)
-  std::unique_ptr<socket::Socket> socket_;
+  // Pointers first (4 bytes each)
+  socket::Socket *socket_{nullptr};
+  std::unique_ptr<socket::Socket> socket_owned_;
 
   // Common state enum for all frame helpers
   // Note: Not all states are used by all implementations

esphome/components/mdns/mdns_component.cpp

@@ -21,8 +21,7 @@
 #include "esphome/components/dashboard_import/dashboard_import.h"
 #endif
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 static const char *const TAG = "mdns";
 
@@ -189,6 +188,5 @@ void MDNSComponent::dump_config() {
 #endif
 }
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 #endif

esphome/components/mdns/mdns_component.h

@@ -6,8 +6,7 @@
 #include "esphome/core/component.h"
 #include "esphome/core/helpers.h"
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 // Helper struct that identifies strings that may be stored in flash storage (similar to LogString)
 struct MDNSString;
@@ -79,6 +78,5 @@ class MDNSComponent : public Component {
   void compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services);
 };
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 #endif

esphome/components/mdns/mdns_esp32.cpp

@@ -7,8 +7,7 @@
 #include "esphome/core/log.h"
 #include "mdns_component.h"
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 static const char *const TAG = "mdns";
 
@@ -56,7 +55,6 @@ void MDNSComponent::on_shutdown() {
   delay(40);  // Allow the mdns packets announcing service removal to be sent
 }
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 
 #endif  // USE_ESP32

esphome/components/mdns/mdns_esp8266.cpp

@@ -9,8 +9,7 @@
 #include "esphome/core/log.h"
 #include "mdns_component.h"
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 void MDNSComponent::setup() {
 #ifdef USE_MDNS_STORE_SERVICES
@@ -52,7 +51,6 @@ void MDNSComponent::on_shutdown() {
   delay(10);
 }
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 
 #endif

esphome/components/mdns/mdns_host.cpp

@@ -6,8 +6,7 @@
 #include "esphome/core/log.h"
 #include "mdns_component.h"
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 void MDNSComponent::setup() {
   // Host platform doesn't have actual mDNS implementation
@@ -15,7 +14,6 @@ void MDNSComponent::setup() {
 
 void MDNSComponent::on_shutdown() {}
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 
 #endif

esphome/components/mdns/mdns_libretiny.cpp

@@ -9,8 +9,7 @@
 
 #include <mDNS.h>
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 void MDNSComponent::setup() {
 #ifdef USE_MDNS_STORE_SERVICES
@@ -46,7 +45,6 @@ void MDNSComponent::setup() {
 
 void MDNSComponent::on_shutdown() {}
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 
 #endif

esphome/components/mdns/mdns_rp2040.cpp

@@ -9,8 +9,7 @@
 
 #include <ESP8266mDNS.h>
 
-namespace esphome {
-namespace mdns {
+namespace esphome::mdns {
 
 void MDNSComponent::setup() {
 #ifdef USE_MDNS_STORE_SERVICES
@@ -51,7 +50,6 @@ void MDNSComponent::on_shutdown() {
   delay(40);
 }
 
-}  // namespace mdns
-}  // namespace esphome
+}  // namespace esphome::mdns
 
 #endif