incubator-nuttx/net/netdev/netdev_default.c

104 lines
3.6 KiB
C

/****************************************************************************
* net/netdev/netdev_default.c
*
* Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
#include <nuttx/net/netdev.h>
#include "utils/utils.h"
#include "netdev/netdev.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: netdev_default
*
* Description:
* Return the default network device. REVISIT: At present this function
* arbitrarily returns the first UP device at the head of the device
* list. Perhaps the default device should be a device name
* configuration option?
*
* So why is this here: It represents my current though for what to do
* if a socket is connected with INADDY_ANY. In this case, I suppose we
* should use the IP address associated with some default device???
*
* Parameters:
* NULL
*
* Returned Value:
* Pointer to default network driver on success; null on failure
*
* Assumptions:
* Called from normal user mode
*
****************************************************************************/
FAR struct net_driver_s *netdev_default(void)
{
FAR struct net_driver_s *dev;
net_lock_t save;
/* Examine each registered network device */
save = net_lock();
for (dev = g_netdevices; dev; dev = dev->flink)
{
/* Is the interface in the "up" state? */
if ((dev->d_flags & IFF_UP) != 0)
{
/* Return a reference to the first device we find that is in the UP
* state.
*/
net_unlock(save);
return dev;
}
}
net_unlock(save);
return NULL;
}
#endif /* CONFIG_NET */