Infinite loop...

[Imadatobanisa]

Hi guys!

Currently I'm making a "Find" function using an infinite loop. But when I run code, it always fails.
I have no idea because I looked and checked function code errors many times....

Here, the code :

#define EXITPOINT -1
//////////////////////////////////////////////////////////////////////////////////////////////
inline int Find(const char *string, int nStart = 0, unsigned int stringlen = 0, char *strTemp = 0, bool bAcceptAll = false) const {
unsigned size = Text.size(); //Get current string size
	if(stringlen == false)stringlen = strlen(string);
	if(stringlen == false || size < stringlen)return EXITPOINT;bool bTemp; 
	if(!strTemp){strTemp = new char[stringlen+1];bTemp = true;}else bTemp = false;
	size-=stringlen-1; //Avoid crash error
//////////////////////////////////////////////////////////////////////////////////
for(unsigned int i = nStart;i < size;i++){
		for(unsigned int j =0;j < stringlen;j++)
			strTemp[j] = (char)Text[i+j].chr;strTemp[j]=0; //Buffer copy
//////////////////////////////////////////////////////////////////////////////////
		if(bAcceptAll == true){
			if(stricmp(strTemp,string) == 0){if(bTemp)delete strTemp;return i;}}else 
			if(strcmp(strTemp,string == 0)){if(bTemp)delete strTemp;return i;}
}
	if(bTemp)delete strTemp; //Free memory if needed
return EXITPOINT;
}

And the code : (I don't know the error which causes the infinite program loop)

#define EXITPOINT -1
CopyText(Text,"aeeossvHellosv!!!");
char *string = "os"; //char *
int nIndex = 0;
/////////////////////////////////////////////////////////////////////////////////////////////
while((nIndex = Find(string,nIndex,0,0),false) != EXITPOINT)
{Delete(nIndex);Delete(nIndex);} //Delete the string "os" 

(Any help would be greatly appreciated).

[helios]

What's wrong with std::string::find() or strstr()?

[Imadatobanisa]

helios wrote:

What's wrong with std::string::find() or strstr()?

No, std::string::find() and strstr() have no errors. :)
But, here are Text and WText structures :

struct TextData
{
	unsigned short chr;
	float size;
	float width;
	float height;
	POINT pt;
};
vector <TextData> Text;
vector <TextData> WText;

So, if I used strstr(), I would analyze the string first, then next step I have to determine the string Index. If I changed a character element, I would re-calculate the character size, character width and character height.

It would be very helpful If someone can detect the error which causes the infinite program loop. :)

[JLBorges]

#include <algorithm>

inline std::ptrdiff_t Find( const unsigned short* string, const std::vector<TextData>& WText,
                             std::size_t nStart = 0, std::size_t stringlen = 0 )
{
    if(!stringlen) { auto p = string ; while(*p++) ++stringlen ; }

    auto pos = std::search( WText.begin()+nStart, WText.end(), string, string+stringlen,
                          [] ( const TextData& t, unsigned short s ) { return t.chr==s ; } ) ;

    return pos == WText.end() ? -1 : pos - WText.begin() ;
}

[Imadatobanisa]

Thanks you, JLBorges. I compiled your code.
This is the output I've just gotten :

error C2958: the left parenthesis '(' found at 'FontClass.cpp(270)' was not matched correctly

auto pos = std::search( WText.begin()+nStart, WText.end(), string, string+stringlen,
                          [] ( const TextData& t, unsigned short s ) { return t.chr==s ; } ) ;

The problem is : I could not find the redundant parenthesis which causes the compiling error the left parenthesis was not matched correctly.

[JLBorges]

An antiquated compiler without support for type inference and lambda expressions?

C++98:

struct textdata_equals
{
    bool operator() ( const TextData& t, unsigned short s ) const
    { return t.chr==s ; }
} ;

inline std::ptrdiff_t Find( const unsigned short* string, const std::vector<TextData>& WText,
                             std::size_t nStart = 0, std::size_t stringlen = 0 )
{
    if(!stringlen) { /*auto*/ const unsigned short* p = string ; while(*p++) ++stringlen ; }

    //auto pos = std::search( WText.begin()+nStart, WText.end(), string, string+stringlen,
    //                      [] ( const TextData& t, unsigned short s ) { return t.chr==s ; } ) ;

    std::vector<TextData>::const_iterator pos = std::search( WText.begin()+nStart, WText.end(),
                                                 string, string+stringlen, textdata_equals() ) ;
    return pos == WText.end() ? -1 : pos - WText.begin() ;
}

[Imadatobanisa]

Wow! So awesome!!! Thanks you so much so much JLBorges!!!