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Wildcard string compare (globbing)

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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

 
GeneralImproved matching with end-of-text Pin
Anders Heie11-May-09 15:20
Anders Heie11-May-09 15:20 
Great code, but when trying this I realized that the following pattern is a match:

Search: ????????
Text to search: ABC

The problem is that the pattern can be LONGER than the text searched, in which case it should return a not found, but instead returns found.

Also, this example succeeds:

Search: y*n
Text to search: yessir

But of course should fail, since I'm looking for a text that ends with n

So I re-wrote your program to this, to correctly handle this situation.

bool StrWildCmp(char* wildstring, char *matchstring){

	
	char stopstring[1];
	*stopstring = 0;

	while(*matchstring) {
		if (*wildstring == '*') {
		  if (!*++wildstring) {
			return true;
		  } else {
			  *stopstring = *wildstring;
		  }
		}

		if(*stopstring) {
			if(*stopstring == *matchstring ) {
				wildstring++;
				matchstring++;
				*stopstring = 0;
			} else {
				matchstring++;
			}
		} else if((*wildstring == *matchstring) || (*wildstring == '?')) {
				wildstring++;
				matchstring++;
		} else {
			return false;
		}

		if(!*matchstring && *wildstring && *wildstring != '*') {
			// matchstring too short
			return false;
		}
	}

  return true;
}


Thanks again for the inspiration. Cool | :cool:
GeneralRe: Improved matching with end-of-text: some cases don't work properly! Pin
roadrunner31412-Aug-09 3:35
roadrunner31412-Aug-09 3:35 
GeneralRe: Improved matching with end-of-text: some cases don't work properly! Pin
sdiazdiaz20-Jun-13 1:50
sdiazdiaz20-Jun-13 1:50 

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