Search a Substring in String(Special

This is a program that i make for searching a substring in string using three variable

1 haystack :The main String

2 needle     :The substring

3 offset       : The starting position of the main string from where substring start search

                        If you set it then it work from specified position other wise it works from 0. 

/*If you have function using less than three variable without using standard function in this stripos function then send me.*/

#include

#include

int stripos(char *haystack,char * needle,int offset)

{

//--------------------------If condition for start the string from given offset-------------------------------------

if(offset>0)

{

haystack=haystack+(offset-1);

}

else

{

offset=1;

}

//------------------------This while loop for check the condition untill the string has characters------

while((*haystack)!='\0')

{

if((*needle)=='\0')   /* This if condition for check for the end of the needle */

{

return offset; 

}

if((*haystack)==(*needle))    /* This condition for matching the character of haystack and needle */

{

if(stripos(haystack+1,needle+1,0)!=-1)    /* This is recursion for checking that all char of needle matched with this*/

{

return offset;

}

else

    break;

}

else

{

if((*(needle-1))!='\0')              /*This condition for returning in the recursion  if */

{

if(*haystack!=*needle)

{

return -1;

}

}

}

haystack++;

offset++;

}

return -1;

}

int main()

{

int pos=0;

pos=stripos("sandeepSinghbisht","Singh",0);

printf("%d",pos);

return 0;

}