/*
    Copyright (C) 1990-2002 by Jarkko Oikarinen, Thomas Helvey,
    Douglas A Lewis and the hybrid ircd development team.  Minor
    changes were made by and are copyrighted by Robert Levin of
    the dancer-ircd development team.
    
    This program 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 1
    of the License, or (at your option) any later version.
    
    This program 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, write to the Free
    Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA  02111-1307, USA.
   
*/

#include <assert.h>
#include <stdio.h>

#ifdef STDC_HEADERS
# include <stdarg.h>
# include <string.h>
#endif

#include <time.h>
#include <unistd.h>

#include "match.h"

#define ToLower(c) (ToLowerTab[(unsigned char)(c)])

const unsigned char ToLowerTab[] =
   {
      0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa,
      0xb, 0xc, 0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14,
      0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d,
      0x1e, 0x1f,
      ' ', '!', '"', '#', '$', '%', '&', 0x27, '(', ')',
      '*', '+', ',', '-', '.', '/',
      '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
      ':', ';', '<', '=', '>', '?',
      '@', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
      'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's',
      't', 'u', 'v', 'w', 'x', 'y', 'z', '[', '\\', ']', '^',
      '_',
      '`', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
      'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's',
      't', 'u', 'v', 'w', 'x', 'y', 'z', '{', '|', '}', '~',
      0x7f,
      0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
      0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
      0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
      0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
      0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9,
      0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
      0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9,
      0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
      0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9,
      0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
      0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9,
      0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
      0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
      0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
      0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9,
      0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
   };

#define MATCH_MAX_CALLS 512  /* ACK! This dies when it's less that this and

we have long lines to parse */

/*
 * Compare if a given string (name) matches the given mask (which can
 * contain wild cards: '*' - match any number of chars, '?' - match any
 * single character.
 *
 * return 1, if match
 *        0, if no match
 */

/*
 * match()
 * Iterative matching function, rather than recursive.
 * Written by Douglas A Lewis (dalewis@acsu.buffalo.edu)
 *
 * behavior change - (Thomas Helvey <tomh@inxpress.net>)
 *
 * removed escape handling, none of the masks used with this function
 * should contain an escape '\\' unless you are searching for one, it is no
 * longer possible to escape * and ?.
 *
 * Moved calls rollup to function body, since match isn't recursive there
 * isn't any reason to have it exposed to the file, this change also has
 * the added benefit of making match reentrant. :)
 *
 * Added asserts, mask and name cannot be null.
 *
 * Changed ma and na to unsigned to get rid of casting.
 *
 * NOTICE: match is now a boolean operation, not a lexical comparison; if a
 * line matches a mask, true (1) is returned, otherwise false (0) is
 * returned.
 */

int match(const char *mask, const char *name)
{
   const unsigned char *m = (const unsigned char *)  mask;
   const unsigned char *n = (const unsigned char *)  name;
   const unsigned char *ma = (const unsigned char *) mask;
   const unsigned char *na = (const unsigned char *) name;
   int wild  = 0;
   int calls = 0;

   assert(0 != mask);
   assert(0 != name);

   if (!mask || !name)
      return 0;

   while (calls++ < MATCH_MAX_CALLS)
   {
      if (*m == '*')
      {
         /* XXX - shouldn't need to spin here, the mask
          * should have been collapsed before match is
          * called
          */
         while (*m == '*')
            m++;

         wild = 1;
         ma = m;
         na = n;
      }

      if (!*m)
      {
         if (!*n)
            return 1;

         for (m--; (m > (const unsigned char *) mask) && (*m == '?'); m--)
            ; /* empty loop */

         if ((*m == '*') && (m > (const unsigned char *) mask))
            return 1;

         if (!wild)
            return 0;

         m = ma;
         n = ++na;
      }
      else if (!*n)
      {
         /* XXX - shouldn't need to spin here, the mask
          * should have been collapsed before match is
          * called
          */
         while (*m == '*')
            m++;

         return (*m == 0);
      }

      if (ToLower(*m) != ToLower(*n) && *m != '?')
      {
         if (!wild)
            return 0;

         m = ma;
         n = ++na;
      }
      else
      {
         if (*m)
            m++;

         if (*n)
            n++;
      }
   }
   return 0;
}


/*
 * collapse a pattern string into minimal components.
 * This particular version is "in place", so that it changes the pattern
 * which is to be reduced to a "minimal" size.
 *
 * behavior modification (Thomas Helvey <tomh@inxpress.net>)
 * Removed mask escapes, we don't escape wildcards or call match on a mask.
 * This change is somewhat subtle, the old version converted \\*** to \\**,
 * the new version blindly converts it to \\*.
 *
 * Removed code that did a lot of work but achieved nothing, testing showed
 * that the code in test for '?' produced exactly the same results as code
 * that ignored '?'. The only thing you can do with a mask is to remove
 * adjacent '*' characters, attempting anything else breaks the re.
 *
 * convert adjacent *'s to a single *
 */
char *collapse(char *pattern)
{
   char *s = pattern;
   char *s1;
   char *t;

   /* XXX - null pointers OK? */
   if (s)
   {
      for (; *s; s++)
      {
         if ('*' == *s)
         {
            t = s1 = s + 1;
            while ('*' == *t)
               ++t;

            if (s1 != t)
            {
               while ((*s1++ = *t++))
                  ; /* empty loop */
            }
         }
      }
   }
   return pattern;
}



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