incubator-nuttx/libs/libc/net/lib_nameindex.c

87 lines
2.8 KiB
C

/****************************************************************************
* libs/libc/net/lib_nameindex.c
*
* 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 <net/if.h>
#include <errno.h>
#include "libc.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: if_nameindex
*
* Description:
* The if_nameindex() function returns an array of if_nameindex structures,
* each containing information about one of the network interfaces on the
* local system. The if_nameindex structure contains at least the following
* entries:
* unsigned int if_index;
* FAR char *if_name;
* The if_index field contains the interface index. The if_name field
* points to the null-terminated interface name. The end of the array
* is indicated by entry with if_index set to zero and if_name set to NULL.
*
* Input Parameters:
* None
*
* Returned Value:
* On success, if_nameindex() returns pointer to the array; on error, NULL
* is returned, and errno is set to indicate the error.
*
****************************************************************************/
FAR struct if_nameindex *if_nameindex(void)
{
FAR struct if_nameindex *ifn;
FAR char *buf;
int i = 0;
int j;
ifn = lib_malloc((sizeof(*ifn) + IF_NAMESIZE) * MAX_IFINDEX);
if (ifn == NULL)
{
set_errno(ENOBUFS);
return NULL;
}
buf = (FAR char *)(ifn + MAX_IFINDEX);
for (j = 1; j <= MAX_IFINDEX; j++)
{
ifn[i].if_name = if_indextoname(j, buf);
if (ifn[i].if_name)
{
ifn[i++].if_index = j;
buf += IF_NAMESIZE;
}
}
ifn[i].if_name = NULL;
ifn[i].if_index = 0;
return ifn;
}