internal Arena *
arena_initialize(u64 size, b8 growable)
{
  Arena *result = 0;
  void *backing_buffer = platform_memory_reserve(size);

  if (backing_buffer != NULL)
  {
    platform_memory_commit(backing_buffer, ARENA_INITIAL_COMMIT_SIZE);

    result = (Arena*) backing_buffer;
    result->backing_buffer = backing_buffer;

    // rhjr: immutable arena header
    result->base_pos = sizeof(Arena);
    result->commit_pos = sizeof(Arena);

    result->growable = growable;
    result->size = size;
  }

  // rhjr: arenas should be instantiated early on in the programs lifetime, that
  //       is why this assertion will also be used in production.
  ASSERT(result != 0);
  return result;
}

internal Arena *
arena_initialize_default()
{
  Arena *result = arena_initialize(ARENA_DEFAULT_RESERVE_SIZE, 1);
  return result;
}

internal void *
arena_allocate(Arena *arena, u64 size)
{
}

internal void
arena_release(Arena *arena)
{
  for (Arena *node = arena->current, *prev = 0; node != 0; node = prev)
  {
    prev = node->prev;
    platform_memory_release(node, node->size);
  }
}