feat(modem): Add support for pausing netif

Closes https://github.com/espressif/esp-protocols/issues/699

components/esp_modem/include/cxx_include/esp_modem_dce.hpp

@@ -103,6 +103,28 @@ public:
     }
 #endif
 
+    /**
+     * @brief Pauses/Unpauses network temporarily
+     * @param do_pause true to pause, false to unpause
+     * @param force true to ignore command failures and continue
+     * @return command_result of the underlying commands
+     */
+    command_result pause_netif(bool do_pause, bool force = false)
+    {
+        command_result result;
+        if (do_pause) {
+            netif.pause();
+            dte->set_command_callbacks();
+            result = device->set_command_mode();
+        } else {
+            result = device->resume_data_mode();
+            if (result == command_result::OK || force) {
+                netif.resume();
+            }
+        }
+        return result;
+    }
+
 protected:
     std::shared_ptr<DTE> dte;
     std::shared_ptr<SpecificModule> device;

components/esp_modem/include/cxx_include/esp_modem_dte.hpp

@@ -145,6 +145,12 @@ public:
      */
     bool recover();
 
+    /**
+     * @brief Set internal command callbacks to the underlying terminal.
+     * Here we capture command replies to be processed by supplied command callbacks in  struct command_cb.
+     */
+    void set_command_callbacks();
+
 protected:
     /**
      * @brief Allows for locking the DTE
@@ -204,12 +210,6 @@ private:
     } inflatable;
 #endif // CONFIG_ESP_MODEM_USE_INFLATABLE_BUFFER_IF_NEEDED
 
-    /**
-     * @brief Set internal command callbacks to the underlying terminal.
-     * Here we capture command replies to be processed by supplied command callbacks in  struct command_cb.
-     */
-    void set_command_callbacks();
-
     /**
      * @brief This abstracts command callback processing and implements its locking, signaling of completion and timeouts.
      */

components/esp_modem/include/cxx_include/esp_modem_netif.hpp

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -54,6 +54,16 @@ public:
      */
     void stop();
 
+    /**
+     * @brief Pause the network interface
+     */
+    void pause();
+
+    /**
+     * @brief Resume the network interface
+     */
+    void resume();
+
     void receive(uint8_t *data, size_t len);
 
 private: