#include <sys/mman.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct ms {
   char b;
   char *s;
   int i;
} Mystruct;

char buf[100];
char *ctos(char b)
{
  if (b == 0) {sprintf(buf, "'\\0'"); return buf; }
  if (b == '\n') {sprintf(buf, "'\\n'"); return buf; }
  if (b <= 'Z' && b >= 'A') {sprintf(buf, "'%c'", b); return buf; }
  if (b <= 'z' && b >= 'a') {sprintf(buf, "'%c'", b); return buf; }
  if (b <= '9' && b >= '0') {sprintf(buf, "'%c'", b); return buf; }
  if (strchr(".,></?;:[{]}|=+-_)(*&^%$#@!'`~", b) != NULL) {sprintf(buf, "'%c'", b); return buf; }
  sprintf(buf, " -- ");
  return buf;
}

void  printt4(int i)
{
  char *s;

  s = (char *) &i;

  printf("%-4s|", ctos(s[0]));
  printf("%-4s|", ctos(s[1]));
  printf("%-4s|", ctos(s[2]));
  printf("%-4s", ctos(s[3]));
}

void printmemory(char *address, int nn)
{
  int i;
  char c[30];
  int *b;
  double d;

  b = (int *) address;
  for (i = 0; i < nn; i++) {
    sprintf(c, "0x%08x", b[i]);
    memcpy(&d, b+i, 8);
    if (i % 2 == 0) {
      printf("0x%x %13d %13s    ", (unsigned int) (b+i), b[i], c);
    } else {
      printf("0x%x %13d %13s    ", (unsigned int) (b+i), b[i], c);
    }
    printt4(b[i]);
    printf("\n");
  }
}

typedef unsigned long UL;

void pm(char *a)
{
  Mystruct *q;
  char *b;

  q = (Mystruct *) a;

  printf("0: %c\n", q->b);
  printf("1: '%s'\n", q->s);
  printf("2: %d\n", q->i);
  
  q += 3;

  printf("3: %c\n", q->b);
  printf("4: '%s'\n", q->s);
  printf("5: %d\n", q->i);
  
  b = a + 16;
  q = (Mystruct *) b;

  printf("6: '%s'\n", q->s);
  printf("7: %d\n", q->i);
  
  q = (Mystruct *) a;
  q = (Mystruct *) q->s;
  printf("8: %c\n", q->b);
  printf("9: %c\n", q[1].b);

  return;
}

int main(int argc, char **argv)
{
  int i, j;

  void *a;
  char *ac;
  int *ip;
  size_t len;
  int *pointers[7];
  char *chars[9];

  len = 256*256*256;

  
  srand(426);

  a = mmap((void *) 0x61610000, len, PROT_READ | PROT_WRITE, MAP_ANON | MAP_FIXED | MAP_PRIVATE, -1, 0);
  if (a == MAP_FAILED) {
    perror("mmap");
    exit(1);
  }

  ac = (char *) 0x61696f40;
  ip = (int *) ac;
  j = 0;
  pointers[0] = ip+1;
  pointers[1] = ip+4;
  pointers[2] = ip+5;
  pointers[3] = ip+7;
  pointers[4] = ip+9;
  pointers[5] = ip+10;
  pointers[6] = ip+13;
  chars[0] = (char *) (ip);
  chars[1] = (char *) (ip+2);
  chars[2] = (char *) (ip+3);
  chars[3] = (char *) (ip+6);
  chars[4] = (char *) (ip+8);
  chars[5] = (char *) (ip+11);
  chars[6] = (char *) (ip+12);
  chars[7] = (char *) (ip+14);
  chars[8] = (char *) (ip+15);

  for (i = 0; i < 7; i++) pointers[i][0] = (int) (ac + rand()%64);
  for (i = 0; i < 9; i++) {
    for (j = 0; j < 4; j++) {
      chars[i][j] = rand()%26 + 'a';
      if (rand()%3 == 0) if (i != 2 || j != 0) chars[i][j] = 0;
    }
  }
  

  printmemory(ac, 16);
  printf("\n");

  pm(ac);
}