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Wildcard string compare (globbing)

By , 15 Feb 2005
 

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

About the Author

Jack Handy
Web Developer
United States United States
Member
No Biography provided

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QuestionPathMatchSpec instead?memberkintz25 Mar '09 - 8:55 
If you have ability to use Windows code you can use PathMatchSpec:
 
http://msdn.microsoft.com/en-us/library/bb773727(VS.85).aspx[^]
AnswerRe: PathMatchSpec instead?memberMandatoryDefault31 Aug '09 - 10:39 
I recommend against PathMatchSpec(). I used that function in my own code and it just bit me. Its wildcard behavior is broken for all but the simplest cases. For example, these two commands incorrectly return false:
 
::PathMatchSpec("C:\\Windows", "C:\\Windows.*");
 
::PathMatchSpec("C:\\Windows", "C:\\Windows.");
Questionwchar_t version?memberrmorales8729 Nov '08 - 20:16 
Anyone tried converting this to using wchar_t* (essentially Unicode) instead of char*?
AnswerRe: wchar_t version?memberrazvar31 Mar '11 - 21:49 
This is great and got my 5 because is simple, fast and useful!
 
Here is the wchar_t version:
 
int wildcmp(const wchar_t *wild, const wchar_t *string)
  {
  const wchar_t *cp = NULL, *mp = NULL;
 
  while ((*string) && (*wild != L'*')) {
    if ((towlower(*wild) != towlower(*string)) && (*wild != L'?')) {
      return 0;
    }
    wild++;
    string++;
  }
 
  while (*string) {
    if (*wild == L'*') {
      if (!*++wild) {
        return 1;
      }
      mp = wild;
      cp = string+1;
    } else if ((towlower(*wild) == towlower(*string)) || (*wild == L'?')) {
      wild++;
      string++;
    } else {
      wild = mp;
      string = cp++;
    }
  }
 
  while (*wild == L'*') {
    wild++;
  }
  return !*wild;
}
 
Example:
 
if (wildcmp(L"*bl?h.*", L"asblah.plm")) {
  //we have a match!
   MessageBox(0,"we have a match!","wildcmp wide",MB_TOPMOST);
} else {
  //no match =(
      MessageBox(0,"no match!","wildcmp wide",MB_TOPMOST);
}

Generalwildcmp in XBLitememberCodeGibbon27 Nov '08 - 13:56 
This is the version of the wildcmp function in XBLite programming language:
 
FUNCTION SBYTE wildcmp( wildcard$, search$)
  ' wildcmp(const char *wild, const char *string)
  ' Written by Jack Handy - jakkhandy@hotmail.com
 
  ULONG cp
  ULONG mp
  
  STRING s_txt$
  ULONG  sp 
  
  STRING w_txt$
  ULONG  wp
 
  IFZ search$   THEN RETURN $$FALSE  
  IFZ wildcard$ THEN RETURN $$FALSE
  
  w_txt$ = wildcard$ + "\0\0"   ' Just to be sure
  s_txt$ = search$   + "\0\0"
  
  DO WHILE (s_txt${sp}) && (w_txt${wp} != '*') 
    IF (w_txt${wp} != s_txt${sp} )  && (w_txt${wp} != '?') THEN RETURN $$FALSE
    
    INC wp
    INC sp
  LOOP
    
  DO WHILE (s_txt${sp})
    IF ( w_txt${wp} == '*' ) THEN    
      INC wp
      IF !(w_txt${wp}) THEN RETURN $$TRUE      
      
      mp = wp     
      cp = sp + 1 
    ELSE 
      IF (w_txt${wp} == s_txt${sp} )  || (w_txt${wp} == '?') THEN    
        INC wp
        INC sp
      ELSE
        wp = mp
      
        sp = cp                   
        IF s_txt${sp} THEN INC cp 
       
      ENDIF
    ENDIF  
  LOOP
    
  DO WHILE (w_txt${wp} == '*' )    
    INC wp
  LOOP
  
  RETURN !w_txt${wp} 
 
END FUNCTION
 

GeneralWildcard string compare in C#memberhaiquang10 Nov '08 - 22:15 
I had converted the wildcmp to C#, it's very easy to wildcard string, thanks so much.
 

bool WildCompare(string strWild, string strEmail)
{
int cp = 0;
int mp = 0;
 
int wildIndex = 0;
int emailIndex = 0;
 
while ((!ValueIsNullOrEmpty(strEmail, emailIndex)) && (ValueAt(strWild, wildIndex) != '*'))
{
if ((ValueAt(strWild, wildIndex) != ValueAt(strEmail, emailIndex)) && (ValueAt(strWild, wildIndex) != '?'))
{
return false;
}
wildIndex++;
emailIndex++;
}
 
while (!ValueIsNullOrEmpty(strEmail,emailIndex))
{
if (ValueAt( strWild, wildIndex) == '*')
{
wildIndex++;
if (ValueIsNullOrEmpty(strWild,wildIndex ))
{
return true;
}
mp = wildIndex;
cp = emailIndex + 1;
}
else if ((ValueAt(strWild, wildIndex).Equals(ValueAt(strEmail, emailIndex)) || (ValueAt(strWild, wildIndex) == '?')))
{
wildIndex++;
emailIndex++;
}
else
{
wildIndex = mp;
emailIndex = cp++;
}
}
 
while (ValueAt(strWild, wildIndex) == '*')
{
wildIndex++;
}
return ValueIsNullOrEmpty(strWild, wildIndex);
}
 

Cry | :(( Sniff | :^) Frown | :( Unsure | :~
GeneralRe: Wildcard string compare in C#memberhaiquang3 Aug '09 - 22:22 
is it good converted?
 
Take SharePoint to new height

GeneralC# Direct Portmemberhempels23 Sep '08 - 15:10 
Well, as direct as I could come up with anyway. Makes use of unsafe to enable pointer arithmetic. Unfortunately, because fixed is required to prevent the GC from moving the pointers, I had to change it to use increment indexers instead of directly manipulating the pointers. Alternatively, you could use stackalloc to instantiate two native char[]'s and copy the values, but that seems contrary to this function's low-memory footprint, high performance goals.
 
Has been tested against every test case presented in the comments section as well as some additional cases I threw in.
 
public unsafe static bool GlobCompare( string glob, string path )
{
      fixed ( char* pGlob = glob, pPath = path )
      {
            int pGlobInc = 0;
            int pPathInc = 0;
 
            int mp = 0;
            int cp = 0;
 
            while ( ( *( pPath + pPathInc ) != 0 ) && ( *( pGlob + pGlobInc ) != '*' ) )
            {
                  if ( ( *( pGlob + pGlobInc ) != *( pPath + pPathInc ) ) && ( *( pGlob + pGlobInc ) != '?' ) )
                  {
                        return false;
                  }
                  pGlobInc++;
                  pPathInc++;
            }
 
            while ( *( pPath + pPathInc ) != 0 )
            {
                  if ( *( pGlob + pGlobInc ) == '*' )
                  {
                        if ( 0 == *( pGlob + ++pGlobInc ) )
                        {
                              return true;
                        }
                        mp = pGlobInc;
                        cp = pPathInc + 1;
                  }
                  else if ( ( *( pGlob + pGlobInc ) == *( pPath + pPathInc ) ) || ( *( pGlob + pGlobInc ) == '?' ) )
                  {
                        pGlobInc++;
                        pPathInc++;
                  }
                  else
                  {
                        pGlobInc = mp;
                        pPathInc = cp++;
                  }
            }
 
            while ( *( pGlob + pGlobInc ) == '*' )
            {
                  pGlobInc++;
            }
            return ( 0 == *( pGlob + pGlobInc ) );
      }
}
General...and yet another C# port [modified]memberDVF27 Aug '10 - 16:59 
public static bool WildcardMatch(string strCompare, string strWild, bool bIgnoreCase)
{
    if (bIgnoreCase)
    {
        strWild = strWild.ToUpper();
        strCompare = strCompare.ToUpper();
    }
 
    // Lengths of strings
    int iWildLen = strWild.Length;
    int iCompareLen = strCompare.Length;
 
    // Used to save position when '*' found in strWild
    // Initialized to invalid values
    int iWildMatched = iWildLen;
    int iCompareBase = iCompareLen;
 
    int iWild = 0;
    int iCompare = 0;
 
    // Match until first wildcard '*'
    while (iCompare < iCompareLen && (iWild >= iWildLen || strWild[iWild] != '*'))
    {
        if (iWild >= iWildLen || (strWild[iWild] != strCompare[iCompare] && strWild[iWild] != '?'))
            return false;
 
        iWild++;
        iCompare++;
    }
 
    // Process wildcard
    while (iCompare < iCompareLen)
    {
        if (iWild < iWildLen)
        {
            if (strWild[iWild] == '*')
            {
                iWild++;
 
                if (iWild == iWildLen)
                    return true;
 
                iWildMatched = iWild;
                iCompareBase = iCompare + 1;
 
                continue;
            }
 
            if (strWild[iWild] == strCompare[iCompare] || strWild[iWild] == '?')
            {
                iWild++;
                iCompare++;
 
                continue;
            }
        }
 
        iWild = iWildMatched;
        iCompare = iCompareBase++;
    }
 
    while (iWild < iWildLen && strWild[iWild] == '*')
        iWild++;
 
    if (iWild < iWildLen)
        return false;
 
    return true;
}

modified on Saturday, August 28, 2010 10:10 PM

GeneralRe: ...and yet another C# portmemberVUnreal21 Sep '10 - 11:22 
Works quite well.
General[Message Removed]memberstonber18 Sep '08 - 14:22 
Spam message removed
GeneralUsing in Artistic Stylememberjimp023 Apr '08 - 4:43 
I am using this in Artistic Style, a popular multi-platform code formatter available at SourceForge.
 
http://astyle.sourceforge.net/
 
Release 1.22 added directory recursion to the project. Wildcard processing was made internal to the program. Linux has a glob function but Windows doesn't. I just used this for both of them. It let me process both platforms in a similar manner.
 
A minor change was made for Windows to make the comparison case insensitive. Linux was left case sensitive.
 
Thanks for making it available. Using this was a lot easier than writing my own. I doubt that mine would have been this sophisticated.
GeneralGeez...memberlarryfr5 Mar '08 - 9:39 
D'Oh! | :doh: Boy do I feel stupid. I worked on an algorithm like this for days, and never got it quite right. Then, I see the wonderful, and simplistic work of someone like this, and it reminds me that sometimes we all are guilty of 'over-engineering'...
 
Thanks Mr. Handy!
QuestionConvert to a replace?memberwilliaps20 Mar '07 - 8:31 
How can this code be converted to do a replace? I need to provide a find/replace dialog in an application and I don't want to jump through the hoops of the Boost library. Can anyone help?
 
Patrick
GeneralC# RexExp versionmemberspinsane4 Nov '06 - 6:30 
Here's RegExp version (may be easily ported to C++).
Pros: More readable, Relies on proven RegExp
Cons: Maybe slower?, If eval string contains RegExp keywords then it might result in unexpected result
 

public static bool Match(string eval, string pattern, bool caseSensitive)
{
bool match = false;
 
// Make input parameters lower-case if case is not an issue
if (!caseSensitive)
{
eval = eval.ToLower();
pattern = pattern.ToLower();
}
 
// Escape regexp special character in pattern
pattern = pattern.Replace(".", @"\.");
 
// Replace valid wildcards with regexp equivalents
pattern = pattern.Replace('?', '.').Replace("*", ".*");
 
// Add boundaries to pattern
pattern = @"\A" + pattern + @"\z";
 
// Search for a match
try
{
match = Regex.IsMatch(eval, pattern);
}
catch /* (ArgumentException ex) */
{
// Syntax error in the regular expression
}
 
// Return result
return match;
}

GeneralKudosmemberquantumred14 Oct '06 - 4:37 
This is tight and clever. Thanks for sharing it.
GeneralRe: Kudosmembermilkplus24 Feb '10 - 11:19 
I agree. This is excellent.
Generalwildcmp(&quot;*&amp;lt;*&amp;gt;&quot;, &quot;&amp;lt;field1&amp;gt;&amp;lt;field2&amp;gt;&quot;) not working [modified]memberDaniel B.6 Sep '06 - 13:14 
Hi,
 
wildcmp("*<*>", "<field1><field2>") return 1 while I think it should return 0 (I maybe wrong, so please tell me).
 
If someone knows how to fix it, I will appreciate.
 
Regards

GeneralRe: wildcmp(&quot;*&amp;lt;*&amp;gt;&quot;, &quot;&amp;lt;field1&amp;gt;&amp;lt;field2&amp;gt;&quot;) not workingmemberradboudp16 Feb '07 - 0:35 
Sure it matches. The first '*' matches ''. '<*>' matches ''
 
Regards,
Radboud
Generalreturn value typememberwdx048 Jan '06 - 15:49 
I think it's better to make the function return a bool value. Anyway, many string comparision functions return 0 when the strings equal.
General*? case matchmembertalimu3 Nov '05 - 23:42 
if wild = "*?.abc", str = "abc.abc"
wildcmp(wild, str) not work
 
but if wild = "?*.abc", str = "abc.abc"
wildcmp(wild, str) do work
 
does anyone have any idea about the case?
GeneralRe: *? case matchmemberkuhnm15 Sep '06 - 2:18 
Having similar problems with "*Hallo 200? ueberalles*.ddd".
It doesn´t work. I think, when the first * is finished, it does not expect an other wildcard in the pattern to follow.
GeneralRe: *? case matchmemberkuhnm18 Sep '06 - 4:48 
Ignore my last email,
like usually the problem sits in front of the screen.
(I mixed a project built with multibyte Chars with this code which was only chars. And of course I used a Umlaut instead of 'ue' in my tests. So no wonder, why it crashed after the '?' )
I´m very sorry!
GeneralGets my 5memberFranc Morales18 Oct '05 - 17:05 
Simple, fast, useful, AND fun to figure out.
 
Well done.
Generalmp and cpmembertwopieman15 Mar '05 - 11:59 
i got the overall flow of the program I didnt get the logic of the second loop completely. I understand that in the second loop it checks if there is nothing after * if so then it is a match but if there is something it stores them in the two pointers and then goes on.
also in the final else it goes like else
{
wild = mp;
string = cp++;
}
am sorry but am not getting the logic totally.
can someone please explain?
GeneralRe: mp and cpmemberradboudp16 Feb '07 - 1:14 
In case you are matching something like the following:
 
"*.abc" to "ab.de.abc"
 
In the second loop it looks for the first character after the asterisk that is the same in the string. At first it matches "*" against "ab". mp = ".abc" during this. Now wild = ".abc" and string = ".de.abc". Obvious no match. On the next loop the first characters do match (both '.') and wild becomes "abc" and string "de.abc". The next loop there is no match and it falls to the else. Here it resets wild to the last mp (mask pattern??) and string to the last cp (character pattern) WITHOUT THE FIRST CHARACTER. (It actually advances cp one position.)
 
Why does it do this. After matching the * against part of the string and encountering a possible poisiton where to match the remainder of the pattern, it continued comparing characters from both to each other. This fialed. Since right before the position of mp there was a *, it is still allowed to add characters to the part that is matched against that. Basically, it goes back to that position but decides that the character that occurs in both strings is not the next character in the pattern but part of the '*' wildcard.
 
In the end it has matched '*' with 'ab.de'.
GeneralOK, but ...memberSam Levy16 Feb '05 - 4:48 
what was changed?
QuestionWhy make 3 loop ?memberDarkYoda Mickael2 Feb '05 - 22:22 
Hello,
 
i think this post is very interesting because is very simple and make very cool work !
 
BUT !
 
I don't understand why you make 3 loop to do it ?
 
I think i don't see all case, because for me only the 2 loop make all the work ?
 
I'm trying to understand all the process to add optionnal char with the ^ escape sequence, for exemple : ^-* match -12 or 12 Wink | ;)
 
Thanks
AnswerRe: Why make 3 loop ?memberJack Handy13 Feb '05 - 10:02 
DarkYoda Mickael wrote:
I don't understand why you make 3 loop to do it ?
 
I think i don't see all case, because for me only the 2 loop make all the work ?

 
The third loop:
 
while (*wild == '*') {
    wild++;
}

 
is there to take care of trailing *'s. Since * means 0 or more chars, "test*" should match "test" just fine. That loop takes care of this case.
 
-Jack
 

There are 10 types of people in this world, those that understand binary and those who don't.


GeneralC# versionmemberSancy26 Oct '04 - 6:23 
Hi, i have a stupid question, could someone give me the c# version Smile | :)
thanks in advance
GeneralRe: C# versionsussPsyk6621 Dec '04 - 3:39 
	private bool wildcmp(string wild, string str) 
	{
		int cp=0, mp=0;
	
		int i=0;
		int j=0;
		while ((i<str.Length) && (wild[j] != '*')) 
		{
			if ((wild[j] != str[i]) && (wild[j] != '?')) 
			{
				return false;
			}
			i++;
			j++;
		}
		
		while (i<str.Length) 
		{
			if (j<wild.Length && wild[j] == '*') 
			{
				if ((j++)>=wild.Length) 
				{
					return true;
				}
				mp = j;
				cp = i+1;
			} 
			else if (j<wild.Length && (wild[j] == str[i] || wild[j] == '?')) 
			{
				j++;
				i++;
			} 
			else 
			{
				j = mp;
				i = cp++;
			}
		}
		
		while (j<wild.Length && wild[j] == '*') 
		{
			j++;
		}
		return j>=wild.Length;
	}
 
This C# version works. I'm sure there are loads of improvements to be made though. Don't flame me for such bad code, I only started C# yesterday;)
GeneralRe: C# versionmemberIonut FIlip22 Feb '05 - 6:15 
A small fix:
   while ((i<str.Length) && (wild[j] != '*'))
should be
   while (i < str.Length && j < wild.Length && wild[j] != '*')
 
And a small improvement for case sensitivity:
private bool wildcmp(string wild, string str, bool case_sensitive)
{
   if (! case_sensitive)
   {
      wild = wild.ToLower();
      str = str.ToLower();
   }
 
   // rest of the code is the same
}

 
Ionut Filip
GeneralRe: C# versionmemberrobagar3 Apr '06 - 16:58 
hiya
 
Just thought I'd share my version of this code
 
- put the whole shebang into a class with public static methods
- fixed a bug where the pattern '?' matches all strings
- added an early-exit test for patterns that don't actually contain wildcards so it just defaults to normal string comparison
 
cheers
Rob
 

 

     /// <summary>
     /// Class providing wildcard string matching.
     /// </summary>
     public class Wildcard
     {
          private Wildcard()
          {
          }
 
          /// <summary>
          /// Array of valid wildcards
          /// </summary>
          private static char[] Wildcards = new char[]{'*', '?'};
 
          /// <summary>
          /// Returns true if the string matches the pattern which may contain * and ? wildcards.
          /// Matching is done without regard to case.
          /// </summary>
          /// <param name="pattern"></param>
          /// <param name="s"></param>
          /// <returns></returns>
          public static bool Match(string pattern, string s)
          {
               return Match(pattern, s, false);
          }
 
          /// <summary>
          /// Returns true if the string matches the pattern which may contain * and ? wildcards.
          /// </summary>
          /// <param name="pattern"></param>
          /// <param name="s"></param>
          /// <param name="caseSensitive"></param>
          /// <returns></returns>
          public static bool Match(string pattern, string s, bool caseSensitive)
          {
               // if not concerned about case, convert both string and pattern
               // to lower case for comparison
               if (!caseSensitive)
               {
                    pattern = pattern.ToLower();
                    s = s.ToLower();
               }
 
               // if pattern doesn't actually contain any wildcards, use simple equality
               if (pattern.IndexOfAny(Wildcards) == -1)
                    return (s == pattern);
 
               // otherwise do pattern matching
               int i=0;
               int j=0;
               while (i < s.Length && j < pattern.Length && pattern[j] != '*')
               {
                    if ((pattern[j] != s[i]) && (pattern[j] != '?'))
                    {
                         return false;
                    }
                    i++;
                    j++;
               }
 
               // if we have reached the end of the pattern without finding a * wildcard,
               // the match must fail if the string is longer or shorter than the pattern
               if (j == pattern.Length)
                    return s.Length == pattern.Length;
         
               int cp=0;
               int mp=0;
               while (i < s.Length)
               {
                    if (j < pattern.Length && pattern[j] == '*')
                    {
                         if ((j++)>=pattern.Length)
                         {
                              return true;
                         }
                         mp = j;
                         cp = i+1;
                    }
                    else if (j < pattern.Length && (pattern[j] == s[i] || pattern[j] == '?'))
                    {
                         j++;
                         i++;
                    }
                    else
                    {
                         j = mp;
                         i = cp++;
                    }
               }
         
               while (j < pattern.Length && pattern[j] == '*')
               {
                    j++;
               }
 
               return j >= pattern.Length;
          }
     }

GeneralRe: C# versionmemberSancy5 Jun '06 - 16:01 
Thanks a lot. This is just what i've been looking for. Smile | :)
 
And it fades like the shadow in the night.
 
PhoeniX
GeneralConvert to java base on C# version [modified, better look :~ ]memberquangtin321 Mar '08 - 21:13 
Java version
We (Qn & Qg) just search and replace to procedure this java version,
    public static boolean matcher(String value, String pattern) {
        if (pattern == null || value == null) {
            return false;
        }
 
        char[] Wildcards = new char[]{'*', '?'};
 
        pattern = pattern.toLowerCase();
        value = value.toLowerCase();
 
        // if pattern doesn't actually contain any wildcards, use simple equality
        if (pattern.indexOf(Wildcards[0]) == -1 && pattern.indexOf(Wildcards[1]) == -1) {
            return value.equals(pattern);
        }
 
        // otherwise do pattern matching
        int i = 0;
        int j = 0;
        while (i < value.length() && j < pattern.length() && pattern.charAt(j) != '*') {
            if (pattern.charAt(j) != value.charAt(i) && pattern.charAt(j) != '?') {
                return false;
            }
            i++;
            j++;
        }
 
        // if we have reached the end of the pattern without finding a * wildcard,
        // the match must fail if the String is longer or shorter than the pattern
        if (j == pattern.length()) {
            return value.length() == pattern.length();
        }
 
        int cp = 0;
        int mp = 0;
        while (i < value.length()) {
            if (j < pattern.length() && pattern.charAt(j) == '*') {
                if ((j++) >= pattern.length()) {
                    return true;
                }
                mp = j;
                cp = i + 1;
            }
            else if (j < pattern.length() && (pattern.charAt(j) == value.charAt(i) || pattern.charAt(j) == '?')) {
                j++;
                i++;
            }
            else {
                j = mp;
                i = cp++;
            }
        }
 
        while (j < pattern.length() && pattern.charAt(j) == '*') {
            j++;
        }
 
        return j >= pattern.length();
    }
 
Unit test
  public void testmatcher() {
        System.out.println("testmatcher");
 
        String[][] matchPaire = {
            {"", ""},
            {"aa", "aa"},
            {"aa", "*"}, //value,pattern
            {"a", "?"},
            {"sdwerporasl;df", "*"},
            {"absdf zzzy", "*zzy"},
            {"abc", "*?"}};
 
        String[][] notMatchPaire = {
            {"", "?"},
            {"ab", "?"},
            {null, null},
            {"", "*a"},
            {"bsadfasdfwer234", "a*"},
            {"a fwer234", "*a"},
            };
 
        for (int i = 0; i < matchPaire.length; i++) {
            System.out.print("paire " + matchPaire[i][0] + " " + matchPaire[i][1]);
            assertTrue(ExchUtils.matcher(matchPaire[i][0], matchPaire[i][1]));
            System.out.println(" ok");
        }
 
        for (int i = 0; i < notMatchPaire.length; i++) {
            System.out.print("paire " + notMatchPaire[i][0] + " " + notMatchPaire[i][1]);
            assertFalse(ExchUtils.matcher(notMatchPaire[i][0], notMatchPaire[i][1]));
            System.out.println(" ok");
        }
    }
 
thank you all.
 
ktmt's member.
modified on Sunday, March 30, 2008 12:42 PM

GeneralRe: C# version - an error!memberMark T.4 Jul '08 - 14:37 
Be aware that there is a bug in this C# version.
I am still working on figuring it out fully, but:
 
in this code segment
int cp=0;
int mp=0;
while (i < s.Length)
{
  if (j < pattern.Length && pattern[j] == '*')
  {
    if ((j++)>=pattern.Length)
      return true;
 
Going into the final "if" line shown here, the maximum value that j may have is (pattern.length-1), due to the first "if" test. Then we see (j++) compared. But, the value of (j++) is the value of "j" BEFORE being incremented and thus is a maximum of (pattern.length-1) and is therefore NEVER >= pattern.length. Only after the if test is completed is j actually incremented.
So the following return is never taken.
 
Perhaps it can be fixed by changing j++ to ++j... but I can't tell that until I complete the analysis.
 
On a slightly different topic, I will state my opinion as a professional programmer. This demonstrates the extremely importance of EXTENSIVE COMMENTS in code explaining NOT what the code does, but "what the code is supposed to do" in each section. If such comments were in place, this would be an easy maintenance fix. Without them, I am having to analyze what the code DOES and, from that, try to discern what the programmer INTENDED the code to do. And, I have to consider all the possible wildcard permutations just like the original programmer did. I essentially have to reinvent the wheel... because the user manual is missing.
 
Everyone, especially Gurus, should put extensive comments in their code on "what it is intended to do". The only downside is lack of job security, because now someone other than you can fix the code. If you have that low of opinion of your worth to your employer, and are also lacking all compassion for others, then don't comment your code.
GeneralRe: C# versionmemberwilliamhix17 Oct '08 - 22:28 
I think this:
 
if ((j++) >= pattern.Length) 
{
  return true;
}
 
Needs to change to this:
 
if (++j >= pattern.Length)
{
 return true;
}
 
Otherwise the early break does not happen and the whole string is searched.
GeneralMany thanks, with 1 small gripe ..memberDavid Patrick29 Sep '04 - 8:41 

most C compare functions return zero when the values are equal, but this function returns non-zero.
 
Personally, I find the non-zero to be more intuitive .. but after years of forcing myself to check for zero I find it a bit counter-intuitive.
 
I think I'll just rename the function when I add it to my library Smile | :)
 
But that certainly wont stop me from using this wonderful routine.
 
Many sincere thanks ...
 

GeneralRe: Many thanks, with 1 small gripe ..memberJack Handy6 Oct '04 - 8:13 
David Patrick wrote:
most C compare functions return zero when the values are equal, but this function returns non-zero.
 
You make a good point. I probably should have made it behave like the strcmp() type functions. I'm a bit afraid to change it at this point since it has been posted for so long. It should be an easy fix for you or anyone else who is used to C style string comparisons. The C++ people here probably like the current behavior I would imagine.
 
-Jack
 

There are 10 types of people in this world, those that understand binary and those who don't.


GeneralRe: Many thanks, with 1 small gripe ..memberVic Mackey16 Oct '04 - 19:33 
I disagree. The return value for strcmp() is more than simply a test for equality, it tells you which string is greater than the other. A zero return value for strcmp() makes sense, but not for wildcmp() since the return value is strictly boolean, match or no match. The current implementation is fine (although some people might be picky about the return type, int vs bool). Perhaps to avoid confusion with string comparison functions, the function should be renamed to wildmatch() or something similar.

GeneralRe: Many thanks, with 1 small gripe ..memberVoja Intermajstor24 Nov '04 - 23:26 

You are completely right, Vic.
 
It is interesting that I have renamed the function in my code to wildmatch(). Wink | ;)
It would be a good new name.
 
Regards, Voja
GeneralNice code...membervoja2125 Aug '04 - 2:30 

This is realy nice & and useful code. I used to write something similar, but your example is simplier and shorter.
Because it lacks comments, I spent some time to understand (before I saw comment form Targys Hmmm | :| - real tutorial Wink | ;) ) and it is clear now. Thanks to both of you!
 
To 'wise' guys, flamers, and other people who has nothing to do instead of arguing:
- If the code has a bug, report but don't pretend you are a genius or a guru. If you can do it better, submit an article.
If you don't like the code, don't use it!
 
And about NULL pointers:
Idiot-proofing should be implemented at the level where data (function arguments) is acquired and prepared, not in such low-level function.
Besides that, I tested several functions from string.h with NULL parameters and every single one threw an exception. No further comments...
 
Regards, Voja
GeneralSlight efficiency improvementmemberBill Buklis9 Jul '04 - 6:53 

Great piece of code, but I have one minor improvement. It appears to me that the variable "cp" doesn't do anything and servers no purpose.
 
If I'm correct, then you can safely remove the line:
cp = string+1;
 
and also remove:
string = cp;
 
and replace:
cp = string++;
 
with:
++string;
 

I'm believe the results would be identical.

GeneralRe: Slight efficiency improvementmemberBill Buklis9 Jul '04 - 7:19 
Maybe I posted too soon. I didn't think there was a way for cp to not equal string+1. But, after thinking about it some more I found a pattern type that would:
 
*???c*
 
It's interesting how the loop keeps shifting back and forth with this type of pattern.
 
However, using a test string of "testing" with the above pattern the match still failed (correctly) using both algorithms. But, there easily may be a pattern and string combination that wouldn't work without cp.
QuestionPathMatchSpec (shlwapi.h)?memberpeterchen28 Jun '04 - 6:56 
Just a thought:
the PathMatchSpec SLWU API could provide similar. I guess it does have some differences (e.g. allowing to specify multiple specs, separated by semicolon), but it might be a simple alternative for many similar tasks.
 

 

we are here to help each other get through this thing, whatever it is Vonnegut jr.

sighist || Agile Programming | doxygen

AnswerRe: PathMatchSpec (shlwapi.h)?memberJack Handy13 Feb '05 - 9:56 
peterchen wrote:
Just a thought:
the PathMatchSpec SLWU API could provide similar. I guess it does have some differences (e.g. allowing to specify multiple specs, separated by semicolon), but it might be a simple alternative for many similar tasks.

 
The wildcmp() function is meant to be lightweight and fast.
 
If the extra functionality of multple specs is needed and you don't want to parse the input yourself then you can go ahead and use the PathMatchSpec() API.
 
Just make sure you don't mind these limitations:
 
1. Adding another dependancy to your executable by including the lib
2. Not portable (wildcmp() compiles fine under unix)
3. More memory overhead (larger code footprint)
4. The horrible slowness
 
I have ran some benchmarks and pasted the results below. I can provide the .cpp file for the benchmarks if anyone is interested.
 
-Jack
 
10MM iterations.
Compiled as a console app using vc6 in release mode with /O2 optimization.
Ran on a pM 1.7ghz
 
"C:\\T*s*.t?t", "C:\\Test\\File.txt"
PathMatchSpec MATCH => 20.5090s
wildcmp MATCH => 1.0320s
 
"C:\\T*s*.t??t", "C:\\Test\\File.txt"
PathMatchSpec NO MATCH => 45.7760s
wildcmp NO MATCH => 0.8910s

 

There are 10 types of people in this world, those that understand binary and those who don't.


GeneralDoesnt seem to work well..sussBikram Singh13 May '04 - 1:56 
Tried these wildcards, and they show different results in your code and in Windows Explorer's search command.
 
??x*
*so*
??so*
??so??
 
Lack of comments in the code also make it a bit difficult to understand. On the whole however, good job!

 

Bikram

GeneralRe: Doesnt seem to work well..memberJack Handy21 Jun '04 - 9:13 
The Windows Explorer search is not a straight wildcard match. It essentially adds *'s to either end of your input string so "b?r" matches "foobar.txt". I take a more literal approach. This function does not presume to be smarter than the caller. It is not only meant for files, it is also very useful for checking hostmasks for example.
 
If you think my function is producing bad results, can you paste an example of the string along with the wildcard?
 
Thanks,
 
Jack
 

There are 10 types of people in this world, those that understand binary and those who don't.


GeneralCase Insensitive wildcmpmemberTechiex16 Mar '04 - 9:36 
I want case insenstive wildcmp function. Could anyone help me?
GeneralRe: Case Insensitive wildcmpmemberNeville Franks16 Mar '04 - 9:52 
Simply wrap the code that compares charaters in toupper() calls.
 
eg.
    if ((toupper(*wild) != toupper(*string)) && (*wild != '?')) {

 
Neville Franks, Author of ED for Windows www.getsoft.com and coming soon: Surfulater www.surfulater.com
 

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