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

*                                                                             *

* 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 <stddef.h>

#include <stdio.h>

#include <unistd.h>

#include <fcntl.h>

#include "sys/alt_dev.h"

#include "priv/alt_file.h"

/*

 * alt_open_fd() is similar to open() in that it is used to obtain a file

 * descriptor for the file named "name". The "flags" and "mode" arguments are

 * identical to the "flags" and "mode" arguments of open().

 *

 * The distinction between the two functions is that the file descriptor

 * structure to use is passed in as an argument, rather than allocated from the

 * list of free file descriptors.

 *

 * This is used by alt_io_redirect() to redirect the stdin, stdout and stderr

 * file descriptors to point to new devices.

 *

 * If the device can not be succesfully opened, then the input file descriptor

 * remains unchanged.

 */

static void alt_open_fd(alt_fd* fd, const char* name, int flags, int mode)

{

  int old;

  old = open (name, flags, mode);

  if (old >= 0)

  {

    fd->dev      = alt_fd_list[old].dev;

    fd->priv     = alt_fd_list[old].priv;

    fd->fd_flags = alt_fd_list[old].fd_flags;

    alt_release_fd (old);

  }

}

/*

 * alt_io_redirect() is called once the device/filesystem lists have been

 * initialised, but before main(). Its function is to redirect standard in,

 * standard out and standard error so that they point to the devices selected by

 * the user (as defined in system.h).

 *

 * Prior to the call to this function, io is directed towards /dev/null. If

 * i/o can not be redirected to the requested device, for example if the device

 * does not exist, then it remains directed at /dev/null.

 */

void alt_io_redirect(const char* stdout_dev,

                     const char* stdin_dev,

                     const char* stderr_dev)

{

  /* Redirect the channels */

  alt_open_fd (&alt_fd_list[STDOUT_FILENO], stdout_dev, O_WRONLY, 0777);

  alt_open_fd (&alt_fd_list[STDIN_FILENO], stdin_dev, O_RDONLY, 0777);

  alt_open_fd (&alt_fd_list[STDERR_FILENO], stderr_dev, O_WRONLY, 0777);

}