interpreters/minibasic/script.c

/****************************************************************************
 * apps/interpreters/minibasic/sript.c
 * Driver file for MiniBasic.
 *
 *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
 *
 * This file was taken from Mini Basic, versino 1.0 developed by Malcolm
 * McLean, Leeds University.  Mini Basic version 1.0 was released the
 * Creative Commons Attribution license which, from my reading, appears to
 * be compatible with the NuttX BSD-style license:
 *
 * 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 <errno.h>

#include "interpreters/minibasic.h"

/****************************************************************************
 * Private Data
 ****************************************************************************/

#ifdef CONFIG_INTERPRETER_MINIBASIC_TESTSCRIPT
/* Here is a simple script to play with */

static FAR char *script =
  "10 REM Test Script\n"
  "20 REM Tests the Interpreter\n"
  "30 REM By Malcolm Mclean\n"
  "35 PRINT \"HERE\"\n"
  "40 PRINT INSTR(\"FRED\", \"ED\", 4)\n"
  "50 PRINT VALLEN(\"12a\"), VALLEN(\"xyz\")\n"
  "60 LET x = SQRT(3.0) * SQRT(3.0)\n"
  "65 LET x = INT(x + 0.5)\n"
  "70 PRINT MID$(\"1234567890\", x, -1)\n";
#endif

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

/****************************************************************************
 * Name: leftstring
 *
 * Description:
 *   Function to slurp in an ASCII file
 *   Params: path - path to file
 *   Returns: malloced string containing whole file
 *
 ****************************************************************************/

static FAR char *loadfile(FAR char *path)
{
  FILE *fp;
  int ch;
  long i = 0;
  long size = 0;
  FAR char *answer;

  fp = fopen(path, "r");
  if (!fp)
    {
      fprintf(stderr, "ERROR: Failed to open %s: %d\n", path, errno);
      return 0;
    }

  fseek(fp, 0, SEEK_END);
  size = ftell(fp);
  fseek(fp, 0, SEEK_SET);

  answer = malloc(size + 100);
  if (!answer)
    {
      fprintf(stderr, "ERROR: Out of memory\n");
      fclose(fp);
      return 0;
    }

  while ((ch = fgetc(fp)) != EOF)
    {
      answer[i++] = ch;
    }

  answer[i++] = 0;

  fclose(fp);
  return answer;
}

/****************************************************************************
 * Name: leftstring
 *
 * Description:
 *
 *
 ****************************************************************************/

static void usage(void)
{
  fprintf(stderr, "MiniBasic: a BASIC interpreter\n");
  fprintf(stderr, "usage:\n");
  fprintf(stderr, "Basic <script>\n");
  fprintf(stderr, "See documentation for BASIC syntax.\n");
  exit(EXIT_FAILURE);
}

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

/****************************************************************************
 * Name: main/basic_main
 *
 * Description:
 *   Call with the name of the Minibasic script file
 *
 ****************************************************************************/

int main(int argc, FAR char *argv[])
{
  FAR char *scr;

  if (argc == 1)
    {
#ifdef CONFIG_INTERPRETER_MINIBASIC_TESTSCRIPT
      basic(script, stdin, stdout, stderr);
#else
      fprintf(stderr, "ERROR: Missing argument.\n");
      usage();
#endif
    }
  else if (argc == 2)
    {
      scr = loadfile(argv[1]);
      if (scr)
        {
          basic(scr, stdin, stdout, stderr);
          free(scr);
        }
    }
  else
    {
      fprintf(stderr, "ERROR: Too many arguments.\n");
      usage();
    }

  return 0;
}