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/******************************************************************************

*                                                                             *

* License Agreement                                                           *

*                                                                             *

* Copyright (c) 2006 Altera Corporation, San Jose, California, USA.           *

* All rights reserved.                                                        *

*                                                                             *

* Permission is hereby granted, free of charge, to any person obtaining a     *

* copy of this software and associated documentation files (the "Software"),  *

* to deal in the Software without restriction, including without limitation   *

* the rights to use, copy, modify, merge, publish, distribute, sublicense,    *

* and/or sell copies of the Software, and to permit persons to whom the       *

* Software is furnished to do so, subject to the following conditions:        *

*                                                                             *

* The above copyright notice and this permission notice shall be included in  *

* all copies or substantial portions of the Software.                         *

*                                                                             *

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR  *

* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,    *

* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE *

* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER      *

* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING     *

* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER         *

* DEALINGS IN THE SOFTWARE.                                                   *

*                                                                             *

* This agreement shall be governed in all respects by the laws of the State   *

* of California and by the laws of the United States of America.              *

*                                                                             *

* Altera does not recommend, suggest or require that this reference design    *

* file be used in conjunction or combination with any other product.          *

******************************************************************************/

#include <stddef.h>

#include "sys/ioctl.h"

#include "sys/alt_errno.h"

#include "sys/alt_warning.h"

#include "priv/alt_file.h"

#include "os/alt_syscall.h"

/*

 * The ioctl() system call is provided so that application code can manipulate

 * the i/o capabilities of a device in device specific ways. This is identical

 * to the standard posix ioctl() function.

 *

 * In general this implementation simply vectors ioctl requests to the

 * apropriate drivers ioctl function (as registered in the drivers alt_dev

 * structure).

 *

 * However in the case of devices (as oposed to filesystem), the TIOCEXCL and

 * TIOCNXCL requests are handled without reference to the driver. These

 * requests are used to lock/release a device for exclusive access.

 *

 * Handling these requests centrally eases the task of device driver

 * development.

 *

 * ALT_IOCTL is mapped onto the ioctl() system call in alt_syscall.h

 */

#ifdef ALT_USE_DIRECT_DRIVERS

#include "system.h"

#include "sys/alt_driver.h"

/*

 * Provide minimal version that calls ioctl routine of provided stdio devices.

 */

int ALT_IOCTL (int file, int req, void* arg)

{

#ifdef ALT_STDIN_PRESENT

    ALT_DRIVER_IOCTL_EXTERNS(ALT_STDIN_DEV);

#endif

#ifdef ALT_STDOUT_PRESENT

    ALT_DRIVER_IOCTL_EXTERNS(ALT_STDOUT_DEV);

#endif

#ifdef ALT_STDERR_PRESENT

    ALT_DRIVER_IOCTL_EXTERNS(ALT_STDERR_DEV);

#endif

#if !defined(ALT_STDIN_PRESENT) && !defined(ALT_STDOUT_PRESENT) && !defined(ALT_STDERR_PRESENT)

    /* Generate a link time warning, should this function ever be called. */

    ALT_STUB_WARNING(ioctl);

#endif

    switch (file) {

#ifdef ALT_STDIN_PRESENT

    case 0: /* stdin file descriptor */

        return ALT_DRIVER_IOCTL(ALT_STDIN_DEV, req, arg);

#endif /* ALT_STDIN_PRESENT */

#ifdef ALT_STDOUT_PRESENT

    case 1: /* stdout file descriptor */

        return ALT_DRIVER_IOCTL(ALT_STDOUT_DEV, req, arg);

#endif /* ALT_STDOUT_PRESENT */

#ifdef ALT_STDERR_PRESENT

    case 2: /* stderr file descriptor */

        return ALT_DRIVER_IOCTL(ALT_STDERR_DEV, req, arg);

#endif /* ALT_STDERR_PRESENT */

    default:

        ALT_ERRNO = EBADFD;

        return -1;

    }

}

#else /* !ALT_USE_DIRECT_DRIVERS */

int ALT_IOCTL (int file, int req, void* arg)

{

  alt_fd* fd;

  int     rc;

  /*

   * A common error case is that when the file descriptor was created, the call

   * to open() failed resulting in a negative file descriptor. This is trapped

   * below so that we don't try and process an invalid file descriptor.

   */

  fd = (file < 0) ? NULL : &alt_fd_list[file];

  if (fd)

  {

    /*

     * In the case of device drivers (not file systems) handle the TIOCEXCL

     * and TIOCNXCL requests as special cases.

     */

    if (fd->fd_flags & ALT_FD_DEV)

    {

      if (req == TIOCEXCL)

      {

        rc = alt_fd_lock (fd);

        goto ioctl_done;

      }

      else if (req == TIOCNXCL)

      {

        rc = alt_fd_unlock (fd);

        goto ioctl_done;

      }

    }

    /*

     * If the driver provides an ioctl() function, call that to handle the

     * request, otherwise set the return code to indicate that the request

     * could not be processed.

     */

    if (fd->dev->ioctl)

    {

      rc = fd->dev->ioctl(fd, req, arg);

    }

    else

    {

      rc = -ENOTTY;

    }

  }

  else

  {

    rc = -EBADFD;

  }

ioctl_done:

  if (rc < 0)

  {

    ALT_ERRNO = -rc;

  }

  return rc;

}

#endif /* ALT_USE_DIRECT_DRIVERS */