feat(lwip): softap can get sta ip from arp table

components/esp_wifi/include/esp_wifi_ap_get_sta_list.h

@@ -36,7 +36,8 @@ typedef struct {
 /**
  * @brief  Get IP information for stations connected to the Wi-Fi AP interface
  *
- * @note   If `CONFIG_LWIP_DHCPS` is disabled then `ip` address field will not be populated in sta list
+ * @note   If `CONFIG_LWIP_DHCPS` is disabled then DHCP lookup is skipped; IPv4 may still be filled from the lwIP ARP cache when available.
+ *         After DHCP (when enabled), any station still without an IP is resolved via ARP table on the same interface.
  *
  * @warning This API works only for the default Wi-Fi AP interface, i.e. esp-netif with key="WIFI_AP_DEF"
  *

components/esp_wifi/remote/include/injected/esp_wifi_ap_get_sta_list.h

@@ -0,0 +1,56 @@
+/*
+ * SPDX-FileCopyrightText: 2026 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include "esp_netif_types.h"
+#include "esp_wifi_types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef ESP_WIFI_MAX_CONN_NUM
+// Number of maximum wifi connection may be undefined if we have no native wifi support on this target
+//   and at the same time there's no native interface injected by the wifi_remote component.
+// In this case, we just let the header compilable, since no wifi API could be used (let's make a sanity check)
+#if !CONFIG_SOC_WIFI_SUPPORTED && !CONFIG_ESP_WIFI_REMOTE_ENABLED && !CONFIG_ESP_HOST_WIFI_ENABLED
+#define ESP_WIFI_MAX_CONN_NUM  (15)
+typedef struct wifi_sta_list_t wifi_sta_list_t;
+#else
+#error WiFi header mismatch! Please make sure you use the correct version of WiFi API
+#endif
+#endif // ESP_WIFI_MAX_CONN_NUM
+
+/**
+ * @brief station list structure
+ */
+typedef struct {
+    int num;                                                /**< Number of connected stations */
+    esp_netif_pair_mac_ip_t sta[ESP_WIFI_MAX_CONN_NUM];     /**< Connected stations */
+} wifi_sta_mac_ip_list_t;
+
+/**
+ * @brief  Get IP information for stations connected to the Wi-Fi AP interface
+ *
+ * @note   If `CONFIG_LWIP_DHCPS` is disabled then DHCP lookup is skipped; IPv4 may still be filled from the lwIP ARP cache when available.
+ *         After DHCP (when enabled), any station still without an IP is resolved via ARP table on the same interface.
+ *
+ * @warning This API works only for the default Wi-Fi AP interface, i.e. esp-netif with key="WIFI_AP_DEF"
+ *
+ * @param[in]   wifi_sta_list Wi-Fi station info list, returned from esp_wifi_ap_get_sta_list()
+ * @param[out]  wifi_sta_ip_mac_list IP layer station info list, corresponding to MAC addresses provided in wifi_sta_list
+ *
+ * @return
+ *         - ESP_OK
+ *         - ESP_ERR_ESP_NETIF_NO_MEM
+ *         - ESP_ERR_ESP_NETIF_INVALID_PARAMS
+ */
+esp_err_t esp_wifi_ap_get_sta_list_with_ip(const wifi_sta_list_t *wifi_sta_list, wifi_sta_mac_ip_list_t *wifi_sta_ip_mac_list);
+
+#ifdef __cplusplus
+}
+#endif

components/esp_wifi/src/wifi_default_ap.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2019-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2019-2026 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -30,7 +30,17 @@ esp_err_t esp_wifi_ap_get_sta_list_with_ip(const wifi_sta_list_t *wifi_sta_list,
         memcpy(wifi_sta_ip_mac_list->sta[i].mac, wifi_sta_list->sta[i].mac, 6);
         memset(&wifi_sta_ip_mac_list->sta[i].ip, 0, sizeof(esp_ip4_addr_t));
     }
-    return esp_netif_dhcps_get_clients_by_mac(ap, num, wifi_sta_ip_mac_list->sta);
+    esp_err_t err = esp_netif_dhcps_get_clients_by_mac(ap, num, wifi_sta_ip_mac_list->sta);
+    if (err != ESP_OK && err != ESP_ERR_NOT_SUPPORTED) {
+        return err;
+    }
+    for (int i = 0; i < num; i++) {
+        if (wifi_sta_ip_mac_list->sta[i].ip.addr == 0) {
+            // Try to get the IP from the ARP table, and not care about the result
+            esp_netif_arp_get_client_by_mac(ap, &wifi_sta_ip_mac_list->sta[i]);
+        }
+    }
+    return ESP_OK;
 #else
     return ESP_ERR_NOT_SUPPORTED;
 #endif