#include <stdio.h>

typedef unsigned char U8;

#define MEMSIZE (128*1024)
#define CHUNKSIZE 8  // bytes
U8 mem[MEMSIZE];


void find_repeat(void)
{
    int start, comp1, comp2;
    int repcount;
    U8 firstbyte;
    
    for(start = 0; start < MEMSIZE - CHUNKSIZE; start += CHUNKSIZE) {
        repcount = 0;
        /* find how many times the memory at start is found in memory */
        firstbyte = mem[start];
        for(comp1 = 0; comp1 < MEMSIZE - CHUNKSIZE; comp1++) {
            if(mem[comp1] == firstbyte) {  // quick optimization
                for(comp2 = 1; comp2<CHUNKSIZE; comp2++) {       /* start at +1 because we've already checked 1st byte */
                    if(mem[comp1+comp2] != mem[start+comp2]) {
                        comp2 = CHUNKSIZE*2;   /* doesn't match - mark it and quit loop */
                    }    
                }
                if(comp2 == CHUNKSIZE) {       /* all bytes match */
                    repcount++;
                }
            }
        }
        // output repcount. 
#if 0        
        printf("%05x: %d\n", start, repcount);
#else
        if(start % (CHUNKSIZE * 64) == 0) {
            printf("\n%05x: ", start);
        }
        if(repcount ==  1) {
            printf(".");
        } else if(repcount < 10) {
            printf("%c", '0'+repcount);
        } else if (repcount < 36) {
            printf("%c", 'A'+repcount-10);
        } else {
            printf("*");
        }
#endif
    }
}

int main() {
    FILE *fin = fopen("FIRMWARE.BIN", "rb");
    
    if(fin == NULL) {
        printf("Could not find FIRMWARE.BIN\n");
        return(-1);
    }
    fread(mem, 1, MEMSIZE, fin);
    fclose(fin);
    find_repeat();
    return 0; 
}