buddy_system_allocator 0.1.0

A bare metal allocator that uses buddy system.
Documentation 
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use crate::linked_list;
use crate::Heap;
use core::alloc::Layout;
use core::mem::size_of;

#[test]
fn test_linked_list() {
    let mut value1: usize = 0;
    let mut value2: usize = 0;
    let mut value3: usize = 0;
    let mut list = linked_list::LinkedList::new();
    unsafe {
        list.push(&mut value1 as *mut usize);
        list.push(&mut value2 as *mut usize);
        list.push(&mut value3 as *mut usize);
    }

    // Test links
    assert_eq!(value3, &value2 as *const usize as usize);
    assert_eq!(value2, &value1 as *const usize as usize);
    assert_eq!(value1, 0);

    // Test iter
    let mut iter = list.iter();
    assert_eq!(iter.next(), Some(&mut value3 as *mut usize));
    assert_eq!(iter.next(), Some(&mut value2 as *mut usize));
    assert_eq!(iter.next(), Some(&mut value1 as *mut usize));
    assert_eq!(iter.next(), None);

    // Test iter_mut

    let mut iter_mut = list.iter_mut();
    assert_eq!(iter_mut.next().unwrap().pop(), &mut value3 as *mut usize);

    // Test pop
    assert_eq!(list.pop(), Some(&mut value2 as *mut usize));
    assert_eq!(list.pop(), Some(&mut value1 as *mut usize));
    assert_eq!(list.pop(), None);
}

#[test]
fn test_empty_heap() {
    let mut heap = Heap::new();
    assert!(heap.alloc(Layout::from_size_align(1, 1).unwrap()).is_err());
}

#[test]
fn test_heap_add() {
    let mut heap = Heap::new();
    assert!(heap.alloc(Layout::from_size_align(1, 1).unwrap()).is_err());

    let space: [usize; 100] = [0; 100];
    unsafe {
        heap.add_to_heap(space.as_ptr() as usize, space.as_ptr().add(100) as usize);
    }
    let addr = heap.alloc(Layout::from_size_align(1, 1).unwrap());
    assert!(addr.is_ok());
}

#[test]
fn test_heap_oom() {
    let mut heap = Heap::new();
    let space: [usize; 100] = [0; 100];
    unsafe {
        heap.add_to_heap(space.as_ptr() as usize, space.as_ptr().add(100) as usize);
    }

    assert!(heap.alloc(Layout::from_size_align(100 * size_of::<usize>(), 1).unwrap()).is_err());
    assert!(heap.alloc(Layout::from_size_align(1, 1).unwrap()).is_ok());
}

#[test]
fn test_heap_alloc_and_free() {
    let mut heap = Heap::new();
    assert!(heap.alloc(Layout::from_size_align(1, 1).unwrap()).is_err());

    let space: [usize; 100] = [0; 100];
    unsafe {
        heap.add_to_heap(space.as_ptr() as usize, space.as_ptr().add(100) as usize);
    }
    for _ in 0..100 {
        let addr = heap.alloc(Layout::from_size_align(1, 1).unwrap()).unwrap();
        heap.dealloc(addr, Layout::from_size_align(1, 1).unwrap());
    }
}