nuttx-apps/nshlib/nsh_slcd.c

/****************************************************************************
 * apps/nshlib/nsh_slcd.c
 *
 *   Copyright (C) 2018 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *   Author: Alan Carvalho de Assis <acassis@gmail.com>
 *
 * 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 <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <assert.h>
#include <debug.h>

#include "nsh.h"
#include "nsh_console.h"

#if defined(HAVE_SLCD_CONSOLE)

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: nsh_clone_console
 *
 * Description:
 *   Wait for the USB keyboard device to be ready
 *
 ****************************************************************************/

static int nsh_clone_console(FAR struct console_stdio_s *pstate)
{
  int fd;

  /* Close stdin */

  (void)close(0);

  /* Open the console */

  fd = open("/dev/console", O_RDONLY);
  if (fd < 0)
    {
      return -ENODEV;
    }

  /* Associate /dev/console as stdin */

  (void)dup2(fd, 0);

  /* Close the console device that we just opened */

  if (fd != 0)
    {
      close(fd);
    }

  /* Use /dev/console as console input */

  pstate->cn_confd = 0;

  /* Create a standard C stream on the console device */

  pstate->cn_constream = fdopen(pstate->cn_confd, "r+");

  return OK;
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: nsh_consolemain (USB console version)
 *
 * Description:
 *   This interfaces maybe to called or started with task_start to start a
 *   single an NSH instance that operates on stdin and stdout.  This
 *   function does not return.
 *
 *   This function handles generic /dev/console character devices for output
 *   but uses a special USB keyboard device for input.  The USB keyboard
 *   requires some special operations to handle the cases where the session
 *   input is lost when the USB keyboard is unplugged and restarted when the
 *   USB keyboard is plugged in again.
 *
 * Input Parameters:
 *   Standard task start-up arguments.  These are not used.  argc may be
 *   zero and argv may be NULL.
 *
 * Returned Values:
 *   This function does not return nor does it ever exit (unless the user
 *   executes the NSH exit command).
 *
 ****************************************************************************/

int nsh_consolemain(int argc, char *argv[])
{
  FAR struct console_stdio_s *pstate = nsh_newconsole();
  int ret;

  DEBUGASSERT(pstate);

  /* Execute the one-time start-up script.  Any output will go to /dev/console. */

#ifdef CONFIG_NSH_ROMFSETC
  (void)nsh_initscript(&pstate->cn_vtbl);
#endif

#if defined(CONFIG_NSH_ARCHINIT) && defined(CONFIG_BOARDCTL_FINALINIT)
  /* Perform architecture-specific final-initialization (if configured) */

  (void)boardctl(BOARDIOC_FINALINIT, 0);
#endif

  /* Try to associate /dev/console as stdin because otherwise /dev/slcd0 will be it */

  ret = nsh_clone_console(pstate);

  if (ret < 0)
    {
      return ret;
    }

  /* Execute the session */

  (void)nsh_session(pstate);
}

#endif /* HAVE_SLCD_CONSOLE */