Subversion Repositories ao486

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

*                                                                             *

* License Agreement                                                           *

*                                                                             *

* Copyright (c) 2004 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 <unistd.h>

#include "sys/alt_errno.h"

#include "sys/alt_warning.h"

#include "priv/alt_file.h"

#include "os/alt_syscall.h"

#ifdef ALT_USE_DIRECT_DRIVERS

int ALT_CLOSE (int fildes)

{

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

  ALT_STUB_WARNING(close);

  /* Indicate an error */

  ALT_ERRNO = ENOSYS;

  return -1;

}

#else /* !ALT_USE_DIRECT_DRIVERS */

/*

 * close() is called by an application to release a file descriptor. If the

 * associated file system/device has a close() callback function registered

 * then this called. The file descriptor is then marked as free.

 *

 * ALT_CLOSE is mapped onto the close() system call in alt_syscall.h

 */

int ALT_CLOSE (int fildes)

{

  alt_fd* fd;

  int     rval;

  /*

   * 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 = (fildes < 0) ? NULL : &alt_fd_list[fildes];

  if (fd)

  {

    /*

     * If the associated file system/device has a close function, call it so

     * that any necessary cleanup code can run.

     */

    rval = (fd->dev->close) ? fd->dev->close(fd) : 0;

    /* Free the file descriptor structure and return. */

    alt_release_fd (fildes);

    if (rval < 0)

    {

      ALT_ERRNO = -rval;

      return -1;

    }

    return 0;

  }

  else

  {

    ALT_ERRNO = EBADFD;

    return -1;

  }

}

#endif /* ALT_USE_DIRECT_DRIVERS */