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Wildcard string compare (globbing)

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4.90/5 (82 votes)
15 Feb 2005 1.1M   96   144
Matches a string against a wildcard string such as "*.*" or "bl?h.*" etc. This is good for file globbing or to match hostmasks.

Usage:

This is a fast, lightweight, and simple pattern matching function.

if (wildcmp("bl?h.*", "blah.jpg")) {
  //we have a match!
} else {
  //no match =(
}

Function:

int wildcmp(const char *wild, const char *string) {
  // Written by Jack Handy - <A href="mailto:jakkhandy@hotmail.com">jakkhandy@hotmail.com</A>
  const char *cp = NULL, *mp = NULL;

  while ((*string) && (*wild != '*')) {
    if ((*wild != *string) && (*wild != '?')) {
      return 0;
    }
    wild++;
    string++;
  }

  while (*string) {
    if (*wild == '*') {
      if (!*++wild) {
        return 1;
      }
      mp = wild;
      cp = string+1;
    } else if ((*wild == *string) || (*wild == '?')) {
      wild++;
      string++;
    } else {
      wild = mp;
      string = cp++;
    }
  }

  while (*wild == '*') {
    wild++;
  }
  return !*wild;
}

License

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Comments and Discussions

 
SuggestionModification with '#' as wildcard joker for digits Pin
Thomas Haase25-Sep-11 23:16
Thomas Haase25-Sep-11 23:16 
First of all I like this code, it is small and fully stand-alone.
I have modified it, because I need an additional wildcard joker that represents digits. Finally the modified function accepts '*', '?' and '#' as joker characters.

int wildcmp_ex(const char *wild, const char *string) {
  const char *cp = NULL, *mp = NULL;

  while (*string) {
    if (*wild == '*') {
      if (!*++wild) {
        return 1;
      }
      mp = wild;
      cp = string+1;
    } else if (((*wild == *string) && (*wild != '#')) || (*wild == '?') || ((*wild == '#') && isdigit(*string))) {
      wild++;
      string++;
    } else {
      if (mp)
      {
        wild = mp;
        string = cp++;
      }
      else
      {
        return 0;
      }
    }
  }

  while (*wild == '*') {
    wild++;
  }
  return !*wild;
}

Thomas Haase


modified 29-Sep-11 8:26am.

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