text: /****************************************************************************
   * apps/nshlib/nsh_stdsession.c
   *
   *   Copyright (C) 2013-2014, 2016 Gregory Nutt. All rights reserved.
   *   Author: Gregory Nutt <gnutt@nuttx.org>
   *
   * 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 Gregory Nutt 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>
  
  #ifdef CONFIG_NSH_CLE
  #  include "system/cle.h"
  #else
  #  include "system/readline.h"
  #endif
  
  #include "nsh.h"
  #include "nsh_console.h"
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nsh_session
   *
   * Description:
   *   This is the common session logic or an NSH session that uses only stdin
   *   and stdout.
   *
   *   This function:
   *   - Executes the NSH logic script
   *   - Presents a greeting
   *   - Then provides a prompt then gets and processes the command line.
   *   - This continues until an error occurs, then the session returns.
   *
   * Input Parameters:
   *   pstate - Abstracts the underlying session.
   *
   * Returned Values:
   *   EXIT_SUCCESS only
   *
   ****************************************************************************/
  
  int nsh_session(FAR struct console_stdio_s *pstate)
  {
    FAR struct nsh_vtbl_s *vtbl;
    int ret;
  
    DEBUGASSERT(pstate);
    vtbl = &pstate->cn_vtbl;
  
  #ifdef CONFIG_NSH_CONSOLE_LOGIN
    /* Login User and Password Check */
  
    if (nsh_stdlogin(pstate) != OK)
      {
        nsh_exit(vtbl, 1);
        return -1; /* nsh_exit does not return */
      }
  #endif /* CONFIG_NSH_CONSOLE_LOGIN */
  
    /* Present a greeting and possibly a Message of the Day (MOTD) */
  
    printf("%s", g_nshgreeting);
  
  #ifdef CONFIG_NSH_MOTD
  # ifdef CONFIG_NSH_PLATFORM_MOTD
    /* Output the platform message of the day */
  
    platform_motd(vtbl->iobuffer, IOBUFFERSIZE);
    printf("%s\n", vtbl->iobuffer);
  
  # else
    /* Output the fixed message of the day */
  
    printf("%s\n", g_nshmotd);
  
  # endif
  #endif
  
    /* Then enter the command line parsing loop */
  
    for (;;)
      {
        /* For the case of debugging the USB console... dump collected USB trace data */
  
  #ifdef CONFIG_NSH_USBDEV_TRACE
        nsh_usbtrace();
  #endif
  
        /* Display the prompt string */
  
        printf("%s", g_nshprompt);
  
        /* Get the next line of input. readline() returns EOF on end-of-file
         * or any read failure.
         */
  
  #ifdef CONFIG_NSH_CLE
        ret = cle(pstate->cn_line, CONFIG_NSH_LINELEN,
                  stdin, stdout);
  #else
        ret = std_readline(pstate->cn_line, CONFIG_NSH_LINELEN);
  #endif
        if (ret != EOF)
          {
            /* Parse process the command */
  
            (void)nsh_parse(vtbl, pstate->cn_line);
          }
  
        /* Readline normally returns the number of characters read,
         * but will return EOF on end of file or if an error occurs.
         * EOF will cause the session to terminate.
         */
  
        else
          {
            printf(g_fmtcmdfailed, "nsh_session", "readline", NSH_ERRNO_OF(-ret));
            return EXIT_SUCCESS;
          }
      }
  
    /* We do not get here, but this is necessary to keep some compilers happy.
     * But others will complain that this code is not reachable.
     */
  
    return EXIT_SUCCESS;
  }
  