apps/net: add ip address connectivity check API

[zs39]

Summary

The system checks connectivity with the input IP address; if no IP address is provided, it defaults to checking DNS server connectivity.

Impact

N/A

Testing

Use the following test cases for testing.

/****************************************************************************
 * apps/examples/hello/hello_main.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>
#include <stdio.h>

#ifdef CONFIG_NETUTILS_PING
#include "netutils/netlib.h"
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * hello_main
 ****************************************************************************/

int main(int argc, FAR char *argv[])
{
  printf("Hello, World!!\n");

#ifdef CONFIG_NETUTILS_PING
  int replies;
  int timeout = 100;  /* 1 second in milliseconds */
  int retry = 10;        /* 3 ping attempts */

  printf("\n=== Network Connectivity Test ===\n");
  
  /* Test case 1: Ping a specific IP address */
  replies = netlib_check_ipconnectivity("223.5.5.5", timeout, retry);
  
  if (replies > 0)
    {
      printf("SUCCESS - Received %d/%d replies\n", replies, retry);
    }
  else if (replies == 0)
    {
      printf("FAILED - No replies received\n");
    }
  else
    {
      printf("ERROR - Error code: %d\n", replies);
    }

#ifdef CONFIG_NETDB_DNSSERVER_IPv4ADDR
  /* Test case 2: Ping default DNS server (from config) */
  printf("\n=== Test Default DNS Server ===\n");
  replies = netlib_check_ipconnectivity(NULL, timeout, retry);
  
  if (replies > 0)
    {
      printf("SUCCESS - Received %d/%d replies\n", replies, retry);
    }
  else if (replies == 0)
    {
      printf("FAILED - No replies received\n");
    }
  else
    {
      printf("ERROR - Error code: %d\n", replies);
    }
#else
  printf("\nDefault DNS server test skipped (CONFIG_NETDB_DNSSERVER_IPv4ADDR not configured)\n");
#endif

#else
  printf("\nNetwork connectivity test is not available\n");
  printf("(CONFIG_NETUTILS_PING is not enabled)\n");
#endif

  return 0;
}

The execution results are as follows

nsh> hello
Hello, World!!

=== Network Connectivity Test ===
SUCCESS - Received 10/10 replies

=== Test Default DNS Server ===
SUCCESS - Received 10/10 replies

[zs39]

apache/nuttx#17685
Documentation supplement here