esp_http_client: add a get HTTP client session errno api for esp_http_client

components/esp_http_client/esp_http_client.c

@@ -904,6 +904,15 @@ error:
     return ret;
 }
 
+int esp_http_client_get_errno(esp_http_client_handle_t client)
+{
+    if (!client) {
+        ESP_LOGE(TAG, "Invalid client handle");
+        return -1;
+    }
+    return esp_transport_get_errno(client->transport);
+}
+
 esp_err_t esp_http_client_set_method(esp_http_client_handle_t client, esp_http_client_method_t method)
 {
     client->connection_info.method = method;

components/esp_http_client/include/esp_http_client.h

@@ -344,6 +344,17 @@ esp_err_t esp_http_client_set_password(esp_http_client_handle_t client, const ch
  */
 esp_err_t esp_http_client_set_authtype(esp_http_client_handle_t client, esp_http_client_auth_type_t auth_type);
 
+/**
+ * @brief      Get HTTP client session errno
+ *
+ * @param[in]  client  The esp_http_client handle
+ *
+ * @return
+ *         - (-1) if invalid argument
+ *         - errno
+ */
+int esp_http_client_get_errno(esp_http_client_handle_t client);
+
 /**
  * @brief      Set http request method
  *