#include <stdio.h>
#include <malloc.h>
#include <string.h>

#ifndef DEBUG_MODE
#define DEBUG_MODE 0
#endif

#define DEBUG(format, ...)                           \
do {                                                 \
        if (DEBUG_MODE==1) {                         \
                printf( format "\n", ##__VA_ARGS__); \
        }                                            \
} while (0)

void sub_str( char *srcTemp, char *dstTemp, int chrStart, int strLength)
{
        int strCount;
        strCount = 0;
        while ( (strLength != 0) || (*srcTemp != '\0')) {
                if (strCount >= chrStart)
                {
                        *dstTemp = *srcTemp;
//                        DEBUG("%s[%d]: s- %s d- %s ", __FUNCTION__,
//                                     __LINE__, *srcTemp, *dstTemp);
                }
                DEBUG("%s[%d]: LOOP(%d)", __FUNCTION__, __LINE__, strCount);

                strCount++;
                *srcTemp++;
                *dstTemp++;
                --strLength;

        }
        *dstTemp = '\0';
}

void token_get( char *srcTemp, char *dstTemp, char *tokChr, int tokNum )
{
        int tokCnt;
        while ( (*srcTemp != '\0') || (tokNum != 0))
        {
                if (*srcTemp == *tokChr)
                {     tokCnt++;
                      tokNum--;
                }

                if (tokNum > 0) {
                        DEBUG("%s[%d]: s- %s d- %s ", __FUNCTION__,
                                     __LINE__, *srcTemp, *dstTemp);
                        *dstTemp = *srcTemp;
                        *dstTemp++;
                }

        *srcTemp++;
        }


 *dstTemp = '\0';
}

int main(void) {

       // Tokenizer demonstation
       char tok0_src[] = "abcdef123gijkl";
       char *tok0_dest = malloc( 4 );
       char tok1_src[] = "!SUBSTRINGS RULE!";
       char *tok1_dest = malloc( strlen( tok1_src)-1 );
       char *t = "!";

       sub_str(tok0_src, tok0_dest, 7, 9);
       printf( "%s[%d]: %s\n", __FILE__, __LINE__, tok0_dest);

       token_get( tok1_src, tok1_dest, t, 1);
       printf( "%s[%d]: T: %s\n", __FILE__, __LINE__, tok1_dest);

}