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Wildcard string compare (globbing)

, 15 Feb 2005
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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

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here

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About the Author

Jack Handy
Web Developer
United States United States
No Biography provided

Comments and Discussions

 
Generaldelphi port [modified] Pin
vovach777 at 23-Dec-14 4:38
membervovach77723-Dec-14 4:38 
QuestionMy vote of 5+ Pin
Sanmayce at 29-Nov-13 8:47
memberSanmayce29-Nov-13 8:47 
GeneralMy vote of 5 Pin
Franc Morales at 29-May-13 16:47
memberFranc Morales29-May-13 16:47 
Questionhelp required for wilcard matching * and # Pin
SaimaAsif at 24-Feb-12 0:56
memberSaimaAsif24-Feb-12 0:56 
GeneralMy vote of 5 Pin
Plamen Petrov at 13-Dec-11 22:37
memberPlamen Petrov13-Dec-11 22:37 
SuggestionModification with '#' as wildcard joker for digits [modified] Pin
Thomas Haase at 26-Sep-11 0:16
memberThomas Haase26-Sep-11 0:16 
QuestionLicence Question Pin
randommark at 23-Nov-10 1:33
memberrandommark23-Nov-10 1:33 
AnswerAnother C# version, with a twist Pin
tomlev at 29-Jun-10 15:50
membertomlev29-Jun-10 15:50 
GeneralObscurity Pin
Chuck O'Toole at 25-Apr-10 19:18
memberChuck O'Toole25-Apr-10 19:18 
AnswerMy C# contribution - recursive, of course! Pin
RenniePet at 26-Mar-10 6:21
memberRenniePet26-Mar-10 6:21 
This strikes me as an obvious place to use recursion. So here goes...

   public class MString
   {
      /// <summary>
      /// Function to compare two strings, where strA may contain wildcard characters '*' and 
      /// '?'. http://en.wikipedia.org/wiki/Wildcard_character
      /// </summary>
      /// <param name="strA">string which may contain wildcards, may be empty, must not be null</param>
      /// <param name="strB">string to compare to, no wildcard processing, may be empty, must not be null</param>
      /// <param name="ignoreCase">true = ignore upper/lower case, false = don't ignore case</param>
      /// <returns>true = match, false = non-match</returns>
      public static bool CompareWWc(string strA, string strB, bool ignoreCase)
      {
         if (ignoreCase)
            return CompareWWc(strA.ToLower(), strB.ToLower());
         else 
            return CompareWWc(strA, strB);
      }
 

      /// <summary>
      /// Recursive function to compare two strings, where strA may contain wildcard characters 
      /// '*' and '?'. http://en.wikipedia.org/wiki/Wildcard_character
      /// </summary>
      /// <param name="strA">string which may contain wildcards, may be empty, must not be null</param>
      /// <param name="strB">string to compare to, no wildcard processing, may be empty, must not be null</param>
      /// <returns>true = match, false = non-match</returns>
      public static bool CompareWWc(string strA, string strB)
      {
         // Top of loop to scan across strA (and strB)
         for (int i = 0; i < strA.Length; i++)
         {
            // Special processing when we hit a '*' in strA
            if (strA[i] == '*')
            {
               // If the '*' is at the end of strA then result = true irrespective of strB
               if (i == strA.Length - 1)
                  return true;  
 
               // Do recursive calls to try to find a match somewhere to the right in strB
               strA = strA.Substring(i + 1);  // The part of strA beyond the '*'
               for (int j = i; j < strB.Length; j++)
                  if (CompareWWc(strA, strB.Substring(j)))
                     return true;
               return false;
            }
 
            // Normal processing for non-'*' characters in strA
            if (i >= strB.Length || (strA[i] != strB[i] && strA[i] != '?'))
               return false;
         }
 
         // We've reached the end of strA and the last character is not '*'
         return strA.Length == strB.Length;
      }
 
   }

And here's a little test sequence:

         if (!MString.CompareWWc("", ""))
            Console.WriteLine("Something wrong!");
 

         if (!MString.CompareWWc("something", "something"))
            Console.WriteLine("Something wrong!");
 
         if (MString.CompareWWc("something", "zomething"))
            Console.WriteLine("Something wrong!");
         
         if (MString.CompareWWc("something", "some"))
            Console.WriteLine("Something wrong!");
         
         if (MString.CompareWWc("something", "something else"))
            Console.WriteLine("Something wrong!");
 

         if (!MString.CompareWWc("s?m?th???", "something"))
            Console.WriteLine("Something wrong!");
         
         if (MString.CompareWWc("s?m?th???", "somethin"))
            Console.WriteLine("Something wrong!");
 

         if (!MString.CompareWWc("*", ""))
            Console.WriteLine("Something wrong!");
         
         if (!MString.CompareWWc("*", "nonsense"))
            Console.WriteLine("Something wrong!");
         
         if (!MString.CompareWWc("non*", "nonsense"))
            Console.WriteLine("Something wrong!");
 

         if (!MString.CompareWWc("*nonsense", "nonsense"))
            Console.WriteLine("Something wrong!");
 
         if (!MString.CompareWWc("non*nse", "nonsense"))
            Console.WriteLine("Something wrong!");
         
         if (MString.CompareWWc("non*nse", "nonsenze"))
            Console.WriteLine("Something wrong!");
         
         if (!MString.CompareWWc("non*n?e", "nonsense"))
            Console.WriteLine("Something wrong!");
 

         if (!MString.CompareWWc("n*on*nse", "nonsense"))
            Console.WriteLine("Something wrong!");
 
         if (!MString.CompareWWc("n*n*nse", "nonsense"))
            Console.WriteLine("Something wrong!");
 
         if (MString.CompareWWc("*non*nse", "nonsenze"))
            Console.WriteLine("Something wrong!");
 
         if (!MString.CompareWWc("n*n*n?e", "nonsense"))
            Console.WriteLine("Something wrong!");
      }

By the way, the name CompareWWc means Compare With Wildcards.
GeneralRe: My C# contribution - recursive, of course! Pin
Erwin de GRoot at 29-Mar-10 2:58
memberErwin de GRoot29-Mar-10 2:58 
GeneralDepends on whether you need to optimize the last few nanoseconds out of it... Pin
RenniePet at 29-Mar-10 8:45
memberRenniePet29-Mar-10 8:45 
GeneralSorry - revised numbers Pin
RenniePet at 29-Mar-10 9:35
memberRenniePet29-Mar-10 9:35 
GeneralRe: Depends on whether you need to optimize the last few nanoseconds out of it... Pin
Erwin de GRoot at 29-Mar-10 9:37
memberErwin de GRoot29-Mar-10 9:37 
GeneralYet another version - 25% faster, I think [modified] Pin
RenniePet at 1-Apr-10 9:24
memberRenniePet1-Apr-10 9:24 
GeneralRe: Yet another version - 25% faster, I think Pin
aleks1k at 21-Sep-11 3:47
memberaleks1k21-Sep-11 3:47 
QuestionI used this function but I how I can catch variables from the * ??? Pin
moh.hijjawi at 20-Oct-09 2:55
membermoh.hijjawi20-Oct-09 2:55 
AnswerRe: I used this function but I how I can catch variables from the * ??? Pin
RenniePet at 1-Apr-10 12:27
memberRenniePet1-Apr-10 12:27 
Questionany updates ? Pin
alhambra-eidos at 2-Jul-09 6:12
memberalhambra-eidos2-Jul-09 6:12 
GeneralImproved matching with end-of-text Pin
Anders Heie at 11-May-09 16:20
memberAnders Heie11-May-09 16:20 
GeneralRe: Improved matching with end-of-text: some cases don't work properly! Pin
roadrunner314 at 12-Aug-09 4:35
memberroadrunner31412-Aug-09 4:35 
GeneralRe: Improved matching with end-of-text: some cases don't work properly! Pin
sdiazdiaz at 20-Jun-13 2:50
membersdiazdiaz20-Jun-13 2:50 
QuestionPathMatchSpec instead? Pin
kintz at 25-Mar-09 9:55
memberkintz25-Mar-09 9:55 
AnswerRe: PathMatchSpec instead? Pin
MandatoryDefault at 31-Aug-09 11:39
memberMandatoryDefault31-Aug-09 11:39 
Questionwchar_t version? Pin
rmorales87 at 29-Nov-08 21:16
memberrmorales8729-Nov-08 21:16 

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