wildcards.c

/*
  Copyright (C) 1996, 1997, 1998, 1999, 2000 Florian Schintke

  This 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 2, or (at your option) any later
  version.

  This 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 with
  the c2html, java2html, pas2html or perl2html source package as the
  file COPYING. If not, write to the Free Software Foundation, Inc.,
  59 Temple Place - Suite 330, Boston, MA
  02111-1307, USA.
*/

/* Documenttitle and purpose:                                       */
/*   Implementation of the UN*X wildcards in C. So they are         */
/*   available in a portable way and can be used whereever          */
/*   needed.                                                        */
/*                                                                  */
/* Version:                                                         */
/*   1.2                                                            */
/*                                                                  */
/* Test cases:                                                      */
/*   Please look into the Shellscript testwildcards.main            */
/*                                                                  */
/* Author(s):                                                       */
/*   Florian Schintke (schintke@gmx.de)                             */
/*                                                                  */
/* Tester:                                                          */
/*   Florian Schintke (schintke@gmx.de)                             */
/*                                                                  */
/* Testing state:                                                   */
/*   tested with the atac tool                                      */
/*   Latest test state is documented in testwildcards.report        */
/*   The program that tested this functions is available as         */
/*   testwildcards.c                                                */
/*                                                                  */
/* Dates:                                                           */
/*   First editing: unknown, but before 04/02/1997                  */
/*   Last Change  : 04/07/2000                                      */
/*                                                                  */
/* Known Bugs:                                                      */
/*                                                                  */

#include <stdio.h>
#include "wildcards.h"

int set (char **wildcard, char **test);
/* Scans a set of characters and returns 0 if the set mismatches at this */
/* position in the teststring and 1 if it is matching                    */
/* wildcard is set to the closing ] and test is unmodified if mismatched */
/* and otherwise the char pointer is pointing to the next character      */

int asterisk (char **wildcard, char **test);
/* scans an asterisk */

int wildcardfit (char *wildcard, char *test)
{
  int fit = 1;

  for (; ('\000' != *wildcard) && (1 == fit) && ('\000' != *test); wildcard++)
    {
      switch (*wildcard)
        {
//!        Skip Square Brackets, as we want to treat these as normal characters rather than set checks.
//!        case '[':
//!      wildcard++; /* leave out the opening square bracket */
//!          fit = set (&wildcard, &test);
//!      /* we don't need to decrement the wildcard as in case */
//!      /* of asterisk because the closing ] is still there */
//!          break;
        case '?':
          test++;
          break;
        case '*':
          fit = asterisk (&wildcard, &test);
      /* the asterisk was skipped by asterisk() but the loop will */
      /* increment by itself. So we have to decrement */
      wildcard--;
          break;
        default:
          fit = (int) (*wildcard == *test);
          test++;
        }
    }
  while ((*wildcard == '*') && (1 == fit))
    /* here the teststring is empty otherwise you cannot */
    /* leave the previous loop */
    wildcard++;
  return (int) ((1 == fit) && ('\0' == *test) && ('\0' == *wildcard));
}

int set (char **wildcard, char **test)
{
  int fit = 0;
  int negation = 0;
  int at_beginning = 1;

  if ('!' == **wildcard)
    {
      negation = 1;
      (*wildcard)++;
    }
  while ((']' != **wildcard) || (1 == at_beginning))
    {
      if (0 == fit)
        {
          if (('-' == **wildcard)
              && ((*(*wildcard - 1)) < (*(*wildcard + 1)))
              && (']' != *(*wildcard + 1))
          && (0 == at_beginning))
            {
              if (((**test) >= (*(*wildcard - 1)))
                  && ((**test) <= (*(*wildcard + 1))))
                {
                  fit = 1;
                  (*wildcard)++;
                }
            }
          else if ((**wildcard) == (**test))
            {
              fit = 1;
            }
        }
      (*wildcard)++;
      at_beginning = 0;
    }
  if (1 == negation)
    /* change from zero to one and vice versa */
    fit = 1 - fit;
  if (1 == fit)
    (*test)++;

  return (fit);
}

int asterisk (char **wildcard, char **test)
{
  /* Warning: uses multiple returns */
  int fit = 1;

  /* erase the leading asterisk */
  (*wildcard)++;
  while (('\000' != (**test))
     && (('?' == **wildcard)
         || ('*' == **wildcard)))
    {
      if ('?' == **wildcard)
    (*test)++;
      (*wildcard)++;
    }
  /* Now it could be that test is empty and wildcard contains */
  /* aterisks. Then we delete them to get a proper state */
  while ('*' == (**wildcard))
    (*wildcard)++;

  if (('\0' == (**test)) && ('\0' != (**wildcard)))
    return (fit = 0);
  if (('\0' == (**test)) && ('\0' == (**wildcard)))
    return (fit = 1);
  else
    {
      /* Neither test nor wildcard are empty!          */
      /* the first character of wildcard isn't in [*?] */
      if (0 == wildcardfit(*wildcard, (*test)))
    {
      do
        {
          (*test)++;
          /* skip as much characters as possible in the teststring */
          /* stop if a character match occurs */
          while (((**wildcard) != (**test))
             && ('['  != (**wildcard))
             && ('\0' != (**test)))
        (*test)++;
        }
      while ((('\0' != **test))?
         (0 == wildcardfit (*wildcard, (*test)))
         : (0 != (fit = 0)));
    }
      if (('\0' == **test) && ('\0' == **wildcard))
    fit = 1;
      return (fit);
    }
}