1  /* Test interface name <-> index conversions.
       2     Copyright (C) 1997-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <errno.h>
      20  #include <stdio.h>
      21  #include <stdlib.h>
      22  #include <string.h>
      23  #include <net/if.h>
      24  
      25  static int
      26  do_test (void)
      27  {
      28    int failures = 0;
      29    struct if_nameindex *idx = if_nameindex (), *p;
      30    if (idx == NULL)
      31      {
      32        if (errno != ENOSYS)
      33  	{
      34  	  printf ("Couldn't get any interfaces.\n");
      35  	  exit (1);
      36  	}
      37        /* The function is simply not implemented.  */
      38        exit (0);
      39      }
      40  
      41    printf ("Idx            Name | Idx           Name\n");
      42  
      43    for (p = idx; p->if_index || p->if_name; ++p)
      44      {
      45        char buf[IFNAMSIZ];
      46        unsigned int ni;
      47        int result;
      48        printf ("%3d %15s | ", p->if_index, p->if_name);
      49        printf ("%3d", ni = if_nametoindex (p->if_name));
      50        printf ("%15s", if_indextoname (p->if_index, buf));
      51        result = (ni != p->if_index || (strcmp (buf, p->if_name)));
      52        if (ni == p->if_index)
      53  	/* We have to make sure that this is not an alias with the
      54  	   same interface number.  */
      55  	if (p->if_index == if_nametoindex (buf))
      56  	  result = 0;
      57        printf ("%10s", result ? "fail" : "okay");
      58        printf ("\n");
      59        failures += result;
      60      }
      61    if_freenameindex (idx);
      62    return failures ? 1 : 0;
      63  }
      64  
      65  #define TEST_FUNCTION do_test ()
      66  #include "../test-skeleton.c"