xref: /netbsd-src/external/bsd/bc/dist/main.c (revision 341df6449e0758ecbc5c5009a483a1f5c365efea)

/*	$NetBSD: main.c,v 1.2 2017/04/18 04:35:18 maya Exp $ */

/*
 * Copyright (C) 1991-1994, 1997, 2006, 2008, 2012-2017 Free Software Foundation, Inc.
 * Copyright (C) 2016-2017 Philip A. Nelson.
 * All rights reserved.
 *
 * 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. The names Philip A. Nelson and Free Software Foundation may not be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY PHILIP A. NELSON ``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 PHILIP A. NELSON OR THE FREE SOFTWARE FOUNDATION 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.
 */

/* main.c: The main program for bc.  */

#include "bcdefs.h"
#include <signal.h>
#include <errno.h>
#include "proto.h"
#include "getopt.h"


/* Variables for processing multiple files. */
static char first_file;

/* Points to the last node in the file name list for easy adding. */
static file_node *last = NULL;

#if defined(LIBEDIT)
/* The prompt for libedit. */
char el_pmtchars[] = "";
static char *el_pmtfunc(void);
static char *el_pmtfunc(void) { return el_pmtchars; }
#endif

/* long option support */
static struct option long_options[] =
{
  {"compile",     0, &compile_only, TRUE},
  {"help",        0, 0,             'h'},
  {"interactive", 0, 0,             'i'},
  {"mathlib",     0, &use_math,     TRUE},
  {"quiet",       0, &quiet,        TRUE},
  {"standard",    0, &std_only,     TRUE},
  {"version",     0, 0,             'v'},
  {"warn",        0, &warn_not_std, TRUE},

  {0, 0, 0, 0}
};


static void
usage (const char *progname)
{
  printf ("usage: %s [options] [file ...]\n%s%s%s%s%s%s%s", progname,
          "  -h  --help         print this usage and exit\n",
	  "  -i  --interactive  force interactive mode\n",
	  "  -l  --mathlib      use the predefined math routines\n",
	  "  -q  --quiet        don't print initial banner\n",
	  "  -s  --standard     non-standard bc constructs are errors\n",
	  "  -w  --warn         warn about non-standard bc constructs\n",
	  "  -v  --version      print version information and exit\n");
}


static void
parse_args (int argc, char **argv)
{
  int optch;
  int long_index;
  file_node *temp;

  /* Force getopt to initialize.  Depends on GNU getopt. */
  optind = 0;

  /* Parse the command line */
  while (1)
    {
      optch = getopt_long (argc, argv, "chilqswv", long_options, &long_index);

      if (optch == EOF)  /* End of arguments. */
	break;

      switch (optch)
	{
	case 0: /* Long option setting a var. */
	  break;

	case 'c':  /* compile only */
	  compile_only = TRUE;
	  break;

	case 'h':  /* help */
	  usage(argv[0]);
	  bc_exit (0);
	  /* NOTREACHED */

	case 'i':  /* force interactive */
	  interactive = TRUE;
	  break;

	case 'l':  /* math lib */
	  use_math = TRUE;
	  break;

	case 'q':  /* quiet mode */
	  quiet = TRUE;
	  break;

	case 's':  /* Non standard features give errors. */
	  std_only = TRUE;
	  break;

	case 'v':  /* Print the version. */
	  show_bc_version ();
	  bc_exit (0);
	  /* NOTREACHED */

	case 'w':  /* Non standard features give warnings. */
	  warn_not_std = TRUE;
	  break;

	default:
	  usage(argv[0]);
	  bc_exit (1);
	}
    }

#ifdef QUIET
  quiet = TRUE;
#endif

  /* Add file names to a list of files to process. */
  while (optind < argc)
    {
      temp = bc_malloc(sizeof(file_node));
      temp->name = argv[optind];
      temp->next = NULL;
      if (last == NULL)
	file_names = temp;
      else
	last->next = temp;
      last = temp;
      optind++;
    }
}

/* The main program for bc. */
int
main (int argc, char **argv)
{
  char *env_value;
  char *env_argv[30];
  int   env_argc;

  /* Interactive? */
  if (isatty(0) && isatty(1))
    interactive = TRUE;

#ifdef HAVE_SETVBUF
  /* attempt to simplify interaction with applications such as emacs */
  (void) setvbuf(stdout, NULL, _IOLBF, 0);
#endif

  /* Environment arguments. */
  env_value = getenv ("BC_ENV_ARGS");
  if (env_value != NULL)
    {
      env_argc = 1;
      env_argv[0] = strdup("BC_ENV_ARGS");
      while (*env_value != 0)
	{
	  if (*env_value != ' ')
	    {
	      env_argv[env_argc++] = env_value;
	      while (*env_value != ' ' && *env_value != 0)
		env_value++;
	      if (*env_value != 0)
		{
		  *env_value = 0;
		  env_value++;
		}
	    }
	  else
	    env_value++;
	}
      parse_args (env_argc, env_argv);
    }

  /* Command line arguments. */
  parse_args (argc, argv);

  /* Other environment processing. */
  if (getenv ("POSIXLY_CORRECT") != NULL)
    std_only = TRUE;

  env_value = getenv ("BC_LINE_LENGTH");
  if (env_value != NULL)
    {
      line_size = atoi (env_value);
      if (line_size < 3 && line_size != 0)
	line_size = 70;
    }
  else
    line_size = 70;

  /* Initialize the machine.  */
  init_storage();
  init_load();

  /* Set up interrupts to print a message. */
  if (interactive)
    signal (SIGINT, use_quit);

  /* Initialize the front end. */
  init_tree();
  init_gen ();
  is_std_in = FALSE;
  first_file = TRUE;
  if (!open_new_file ())
    bc_exit (1);

#if defined(LIBEDIT)
  if (interactive) {
    /* Enable libedit support. */
    edit = el_init ("bc", stdin, stdout, stderr);
    hist = history_init();
    el_set (edit, EL_EDITOR, "emacs");
    el_set (edit, EL_HIST, history, hist);
    el_set (edit, EL_PROMPT, el_pmtfunc);
    el_source (edit, NULL);
    history (hist, &histev, H_SETSIZE, INT_MAX);
  }
#endif

#if defined(READLINE)
  if (interactive) {
    /* Readline support.  Set both application name and input file. */
    rl_readline_name = "bc";
    rl_instream = stdin;
    using_history ();
  }
#endif

  /* Do the parse. */
  yyparse ();

  /* End the compile only output with a newline. */
  if (compile_only)
    printf ("\n");

  bc_exit (0);
}


/* This is the function that opens all the files.
   It returns TRUE if the file was opened, otherwise
   it returns FALSE. */

int
open_new_file (void)
{
  FILE *new_file;
  file_node *temp;

  /* Set the line number. */
  line_no = 1;

  /* Check to see if we are done. */
  if (is_std_in) return (FALSE);

  /* Open the other files. */
  if (use_math && first_file)
    {
      /* Load the code from a precompiled version of the math libarary. */
      CONST char **mstr;

      /* These MUST be in the order of first mention of each function.
	 That is why "a" comes before "c" even though "a" is defined after
	 after "c".  "a" is used in "s"! */
      (void) lookup (strdup("e"), FUNCT);
      (void) lookup (strdup("l"), FUNCT);
      (void) lookup (strdup("s"), FUNCT);
      (void) lookup (strdup("a"), FUNCT);
      (void) lookup (strdup("c"), FUNCT);
      (void) lookup (strdup("j"), FUNCT);
      mstr = libmath;
      while (*mstr) {
           load_code (*mstr);
	   mstr++;
      }
    }

  /* One of the argv values. */
  if (file_names != NULL)
    {
      new_file = fopen (file_names->name, "r");
      if (new_file != NULL)
	{
	  new_yy_file (new_file);
	  temp = file_names;
	  file_name  = temp->name;
	  file_names = temp->next;
	  free (temp);
	  return TRUE;
	}
      fprintf (stderr, "File %s is unavailable.\n", file_names->name);
      bc_exit (1);
    }

  /* If we fall through to here, we should return stdin. */
  new_yy_file (stdin);
  is_std_in = TRUE;
  return TRUE;
}


/* Set yyin to the new file. */

void
new_yy_file (FILE *file)
{
  if (!first_file) fclose (yyin);
  yyin = file;
  first_file = FALSE;
}


/* Message to use quit.  */

void
use_quit (int sig)
{
#ifdef DONTEXIT
  int save = errno;
  write (1, "\n(interrupt) use quit to exit.\n", 31);
  signal (SIGINT, use_quit);
  errno = save;
#else
  write (1, "\n(interrupt) Exiting bc.\n", 26);
  bc_exit(0);
#endif
}