fs/fs_ioctl.c

/****************************************************************************
 * fs/fs_ioctl.c
 *
 *   Copyright (C) 2007-2010 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * 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>

#include <sys/ioctl.h>
#include <sched.h>
#include <errno.h>

#include <net/if.h>

#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
# include <nuttx/net.h>
#endif

#include "fs_internal.h"

/****************************************************************************
 * Global Functions
 ****************************************************************************/

/****************************************************************************
 * Name: ioctl
 *
 * Description:
 *   Perform device specific operations.
 *
 * Parameters:
 *   fd       File/socket descriptor of device
 *   req      The ioctl command
 *   arg      The argument of the ioctl cmd
 *
 * Return:
 *   >=0 on success (positive non-zero values are cmd-specific)
 *   -1 on failure withi errno set properly:
 *
 *   EBADF
 *     'fd' is not a valid descriptor.
 *   EFAULT
 *     'arg' references an inaccessible memory area.
 *   EINVAL
 *     'cmd' or 'arg' is not valid.
 *   ENOTTY
 *     'fd' is not associated with a character special device.
 *   ENOTTY
 *      The specified request does not apply to the kind of object that the
 *      descriptor 'fd' references.
 *
 ****************************************************************************/

int ioctl(int fd, int req, unsigned long arg)
{
  int err;
#if CONFIG_NFILE_DESCRIPTORS > 0
  FAR struct filelist *list;
  FAR struct file     *this_file;
  FAR struct inode    *inode;
  int                  ret = OK;

  /* Did we get a valid file descriptor? */

  if ((unsigned int)fd >= CONFIG_NFILE_DESCRIPTORS)
#endif
    {
      /* Perform the socket ioctl */

#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
      if ((unsigned int)fd < (CONFIG_NFILE_DESCRIPTORS+CONFIG_NSOCKET_DESCRIPTORS))
        {
          return netdev_ioctl(fd, req, arg);
        }
      else
#endif
        {
          err = EBADF;
          goto errout;
        }
    }

#if CONFIG_NFILE_DESCRIPTORS > 0
  /* Get the thread-specific file list */

  list = sched_getfiles();
  if (!list)
    {
      err = EMFILE;
      goto errout;
    }

  /* Is a driver registered? Does it support the ioctl method? */

  this_file = &list->fl_files[fd];
  inode     = this_file->f_inode;

  if (inode && inode->u.i_ops && inode->u.i_ops->ioctl)
    {
      /* Yes, then let it perform the ioctl */

      ret = (int)inode->u.i_ops->ioctl(this_file, req, arg);
      if (ret < 0)
        {
          err = -ret;
          goto errout;
        }
    }
  return ret;
#endif

errout:
  *get_errno_ptr() = err;
  return ERROR;
}