#define TINY_ALLOCATOR_IMPLEMENTATION
#include "base/allocator.h"

#include <stdint.h>
#include <stdlib.h>

static size_t fail_index = SIZE_MAX;
static size_t calls;
static size_t outstanding;

static int
should_fail(void)
{
  return calls++ == fail_index;
}

void *
tiny_alloc(size_t size)
{
  void *result;
  if (should_fail())
    {
      return NULL;
    }
  result = malloc(size);
  if (result != NULL)
    {
      outstanding++;
    }
  return result;
}

void *
tiny_calloc(size_t count, size_t size)
{
  void *result;
  if ((size != 0 && count > SIZE_MAX / size) || should_fail())
    {
      return NULL;
    }
  result = calloc(count, size);
  if (result != NULL)
    {
      outstanding++;
    }
  return result;
}

void *
tiny_realloc(void *memory, size_t size)
{
  void *result;
  if (size == 0)
    {
      tiny_free(memory);
      return NULL;
    }
  if (should_fail())
    {
      return NULL;
    }
  result = realloc(memory, size);
  if (result != NULL && memory == NULL)
    {
      outstanding++;
    }
  return result;
}

void
tiny_free(void *memory)
{
  if (memory != NULL)
    {
      free(memory);
      if (outstanding > 0)
        {
          outstanding--;
        }
    }
}

void
tiny_allocator_reset(void)
{
  fail_index = SIZE_MAX;
  calls = 0;
}

void
tiny_allocator_fail_after(size_t allocation_index)
{
  fail_index = allocation_index;
  calls = 0;
}

size_t
tiny_allocator_call_count(void)
{
  return calls;
}

size_t
tiny_allocator_outstanding(void)
{
  return outstanding;
}