/**
 * malloc-info
 *   Some experiments to see what information we can learn from malloc.
 */

// +---------+--------------------------------------------------------
// | Headers |
// +---------+

#include <stdlib.h>     // For malloc and free
#include <malloc.h>     // For malloc_stats
#include <stdio.h>      // For printf and such
#include "expt.h"       // For EXPERIMENT and PRINT_PTR


// +--------+---------------------------------------------------------
// | Macros |
// +--------+

/**
 * MEMINFO () - Print information on memory usage.
 */
#define MEMINFO() \
  BLOCK ( 						\
    PRINT_INT (mem_allocated ()); 			\
  )

// The next two lines may be added as desired.
    // EXPERIMENT (malloc_stats ()());			\
    // EXPERIMENT (mem_info ());			\


// +---------+--------------------------------------------------------
// | Helpers |
// +---------+

/**
 * Determine how much memory has been allocated by malloc.
 */
int
mem_allocated ()
{
  struct mallinfo info = mallinfo ();
  return info.uordblks;
} // mem_allocated

/**
 * Print out the mallinfo struct.
 */
void
mem_info ()
{
  struct mallinfo info = mallinfo ();
  fprintf (stderr, "arena:     %d\n", info.arena);
  fprintf (stderr, "ordblks:   %d\n", info.ordblks);
  fprintf (stderr, "smblks:    %d\n", info.smblks);
  fprintf (stderr, "hblks:     %d\n", info.hblks);
  fprintf (stderr, "hblkhd:    %d\n", info.hblkhd);
  fprintf (stderr, "usmblks:   %d\n", info.smblks);
  fprintf (stderr, "uordblks:  %d\n", info.uordblks);
  fprintf (stderr, "fordblks:  %d\n", info.fordblks);
  fprintf (stderr, "keepcost:  %d\n", info.keepcost);
} // mem_info


// +------+-----------------------------------------------------------
// | Main |
// +------+

int 
main ()
{
  char *p1;
  char *p2;

  MEMINFO();

  EXPERIMENT (p1 = (char *) malloc (100));
  PRINT_PTR (p1);
  MEMINFO ();

  EXPERIMENT (p2 = (char *) malloc (32));
  PRINT_PTR (p2);
  MEMINFO ();

  EXPERIMENT (free (p1));
  MEMINFO ();

  EXPERIMENT (free (p2));
  MEMINFO ();

  return 0;
} // main