public void deallocating_everything_in_an_arena_resets_it()
{
var mem = new MemorySimulator(Mega.Bytes(1));
var subject = new Allocator(100, Mega.Bytes(1), mem);
long ptr1 = subject.Alloc(512).Value;
long ptr2 = subject.Alloc(512).Value;
long ptr3 = subject.Alloc(512).Value;
subject.Deref(ptr1);
subject.Deref(ptr2);
long ptr4 = subject.Alloc(512).Value;
subject.Deref(ptr3);
subject.Deref(ptr4);
// should be reset now, and next alloc goes back to start
long ptrFinal = subject.Alloc(512).Value;
Assert.That(ptrFinal, Is.EqualTo(ptr1));
}
public void deallocating_an_old_allocation_does_nothing()
{
// Older items just hang around until the entire arena is abandoned
var mem = new MemorySimulator(Mega.Bytes(1));
var subject = new Allocator(100, Mega.Bytes(10), mem);
long ptr1 = subject.Alloc(byteCount: 256).Value;
long ptr2 = subject.Alloc(byteCount: 256).Value;
subject.Deref(ptr1);
long ptr3 = subject.Alloc(byteCount: 512).Value;
Assert.That(ptr3, Is.GreaterThan(ptr2));
}
public void can_directly_deallocate_a_pointer()
{
var mem = new MemorySimulator(Mega.Bytes(1));
var subject = new Allocator(100, Mega.Bytes(10), mem);
long ptr = subject.Alloc(byteCount: 256).Value;
subject.Deref(ptr);
var ar = subject.CurrentArena();
var refs = subject.ArenaRefCount(ar);
Assert.That(refs.Value, Is.Zero);
}
public void can_add_and_remove_current_referenced_pointers()
{
// This increments and decrements ref counts?
// Free is the equivalent of directly setting ref count to zero? Or is it just a synonym for Deref?
// We can keep an overall refcount for the arena and ignore the individual references (except for the head, as an optimisation)
// We don't protect from double-free
var mem = new MemorySimulator(Mega.Bytes(1));
var subject = new Allocator(100, Mega.Bytes(1), mem);
long ptr = subject.Alloc(byteCount: 256).Value;
subject.Reference(ptr);
subject.Reference(ptr);
subject.Deref(ptr);
Assert.Pass();
}
