// For RTLD_NEXT
#define _GNU_SOURCE

#include <stdio.h>
#include <dlfcn.h>
#include <stdlib.h>
#include <string.h>

static FILE *(*real_fopen)(const char *, const char *) = NULL;

#define SEARCH_TOKEN_SIZE 6
char mySearchToken[SEARCH_TOKEN_SIZE] = "That's";

void *searchData(char *data, int len, void *start, void *end) {
  void *i;

  for(i = start; i < end; i += 1) {
    if (memcmp(i, data, len) == 0 && i != (void *)data) {
      return i;
    }
  }

  return NULL;
}


FILE * fopen ( const char * filename, const char * mode ) {
  printf("HUEBR, GIBE DATA PLOS, OR I REPORT U HUEHUE\n");
  printf("MI NO LIK U FIL, MI UPEN HUE.TXT\n");

  return real_fopen("hue.txt", "w");
}

void __attribute__((constructor)) initialize(void) {
  real_fopen = dlsym(RTLD_NEXT, "fopen");

  if (real_fopen == NULL) {
    printf("What? We couldn't find our fopen!!!!\n");
    exit(255); // This will crash the program since it isn't expecting to exit in the constructor
  }

  void *addr = searchData(mySearchToken, SEARCH_TOKEN_SIZE, (void *)0x4006e0, (void*)0x400791 ); // Thats for 64 bit.

  printf("Token Addr: %p\n", addr);
}