/*
  Copyright (C) 1995-2022 Free Software Foundation, Inc.

  This file is part of GNU Inetutils.

  GNU Inetutils is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or (at
  your option) any later version.

  GNU Inetutils is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see `http://www.gnu.org/licenses/'. */

/*
 * Copyright (c) 1985, 1993, 1994
 *	The Regents of the University of California.  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. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 */

#include <config.h>

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "ftp_var.h"

/* Increase allocated length of `*startl' with `add'
 * beyond `*track',  should present length not suffice.
 * `*track' points to last character in use.  All of
 * the values `*start', `*track', * and `*size' are
 * updated during a successful reallocation.
 * Return zero on success.
 */
static int
lengthen (char **start, char **track, size_t *size, size_t add)
{
  char *new;
  size_t offset = (size_t) (*track - *start);

  if (*track < *start)
    return EXIT_FAILURE;	/* Sanity check.  */

  if (offset + add < *size)
    return EXIT_SUCCESS;	/* Sufficient allocation.  */

  new = realloc (*start, *size + add);
  if (!new)
    return EXIT_FAILURE;	/* Parameters are unchanged here.  */

  *start = new;
  *size += add;
  *track = *start + offset;

  return EXIT_SUCCESS;
}

void
domacro (int argc, char *argv[])
{
  int i, j, count = 2, loopflg = 0, allocflg = 0;
  char *cp1, *cp2;
  char *line2;		/* Saved original of `line'.  */
  size_t line2len;	/* Its allocated length.  */
  struct cmd *c;

  if (argc < 2 && !another (&argc, &argv, "macro name"))
    {
      printf ("Usage: %s macro_name.\n", argv[0]);
      code = -1;
      return;
    }
  for (i = 0; i < macnum; ++i)
    {
      if (!strncmp (argv[1], macros[i].mac_name,
		    sizeof (macros[i].mac_name)))
	{
	  break;
	}
    }
  if (i == macnum)
    {
      printf ("'%s' macro not found.\n", argv[1]);
      code = -1;
      return;
    }

  line2 = line;
  line2len = linelen;

  /* Generate a replacement for `line' to be used during
   * macro evaluation.  There might appear some intr(),
   * so care must be taken before changing `line'.
   * The original is available as LINE2.
   *
   * Initially allocate an amount sufficient for
   * storing a copy of the original `line', which
   * is repeatedly reused once for each text line
   * of the stored macro definition.
   */
  cp2 = malloc (strlen (line2) + 2);
  if (!cp2)
    {
      printf ("System refused resources for macro '%s'.\n", argv[1]);
      line = line2;
      linelen = line2len;
      code = -1;
      return;
    }

  linelen = strlen (line2) + 2;
  line = cp2;
  *line = '\0';

  do
    {
      cp1 = macros[i].mac_start;
      while (cp1 != macros[i].mac_end)
	{
	  /* Skip initial white space on each line of input.  */
	  while (isspace (*cp1))
	    {
	      cp1++;
	    }
	  /* Translate a line of text from macro definition
	   * and put it in `line'.  This global variable is
	   * referenced by some parsing functions, so the
	   * translation target cannot be changed easily.
	   */
	  cp2 = line;
	  while (*cp1 != '\0')
	    {
	      /* Usually two characters suffice.
	       * This covers the default case below.
	       */
	      if (lengthen (&line, &cp2, &linelen, 2))
		{
		  allocflg = 1;
		  goto end_exec;
		}
	      switch (*cp1)
		{
		case '\\':		/* Escaping character.  */
		  *cp2++ = *++cp1;
		  break;
		case '$':		/* Substitution.  */
		  if (isdigit (*(cp1 + 1)))
		    {
		      /* Argument expansion.  */
		      j = 0;
		      while (isdigit (*++cp1))
			j = 10 * j + *cp1 - '0';
		      cp1--;
		      if (argc - 2 >= j)
			{
			  if (lengthen (&line, &cp2, &linelen,
					strlen (argv[j + 1]) + 2))
			    {
			      allocflg = 1;
			      goto end_exec;
			    }
			  strcpy (cp2, argv[j + 1]);
			  cp2 += strlen (argv[j + 1]);
			}
		      break;
		    }
		  if (*(cp1 + 1) == 'i')
		    {
		      /* The loop counter "$i" was detected.  */
		      loopflg = 1;
		      cp1++;		/* Back to last used char.  */
		      if (count < argc)
			{
			  if (lengthen (&line, &cp2, &linelen,
					strlen (argv[count]) + 2))
			    {
			      allocflg = 1;
			      goto end_exec;
			    }
			  strcpy (cp2, argv[count]);
			  cp2 += strlen (argv[count]);
			}
		      break;
		    }
		  /* Intentional fall through, since no acceptable
		   * use of '$' was detected.  Present input is the
		   * dollar sign.
		   */
		  /* FALLTHROUGH */
		default:
		  *cp2++ = *cp1;	/* Copy present character.  */
		  break;
		}
	      /* Advance to next usable character.  */
	      if (*cp1 != '\0')
		cp1++;
	    }
	  *cp2 = '\0';
	  makeargv ();
	  if (margv[0] == NULL)
	    return;
	  c = getcmd (margv[0]);

	  if (c == (struct cmd *) -1)
	    {
	      printf ("?Ambiguous command: '%s'.\n", margv[0]);
	      code = -1;
	      loopflg = 0;
	      break;
	    }
	  else if (c == 0)
	    {
	      printf ("?Invalid command: '%s'.\n", margv[0]);
	      code = -1;
	      loopflg = 0;
	      break;
	    }
	  else if (c->c_conn && !connected)
	    {
	      printf ("Not connected, needed for '%s'.\n", margv[0]);
	      code = -1;
	      loopflg = 0;
	      break;
	    }
	  else
	    {
	      if (verbose)
		printf ("%s\n", line);
	      (*c->c_handler) (margc, margv);
	      if (bell && c->c_bell)
		putchar ('\007');

	      /* The arguments set at the time of invoking
	       * the macro must be recovered, to be used
	       * in parsing next line of macro definition.
	       */
	      strcpy (line, line2);	/* Known to fit.  */
	      makeargv ();		/* Get the arguments.  */
	      argc = margc;
	      argv = margv;
	    }
	  if (cp1 != macros[i].mac_end)
	    cp1++;
	}
    }
  while (loopflg && ++count < argc);

end_exec:
  if (allocflg)
    {
      printf ("Memory allocation failed for macro '%s'.\n", argv[1]);
      code = -1;
    }
  free (line);
  line = line2;
  linelen = line2len;
}
