flex_alloc/storage/
spill.rs

1use core::alloc::Layout;
2use core::marker::PhantomData;
3use core::ptr::{self, NonNull};
4
5use crate::alloc::{AllocError, AllocateIn, Allocator, AllocatorDefault, Fixed, Spill};
6
7/// An allocator which consumes the provided fixed storage before deferring to the
8/// contained `A` instance allocator for further allocations
9#[derive(Debug, Default, Clone)]
10pub struct SpillStorage<'a, I: 'a, A> {
11    pub(crate) buffer: I,
12    pub(crate) alloc: A,
13    _pd: PhantomData<&'a mut ()>,
14}
15
16impl<I, A: Allocator> SpillStorage<'_, I, A> {
17    #[inline]
18    pub(crate) fn new_in(buffer: I, alloc: A) -> Self {
19        Self {
20            buffer,
21            alloc,
22            _pd: PhantomData,
23        }
24    }
25}
26
27impl<'a, I, A> AllocateIn for SpillStorage<'a, I, A>
28where
29    I: AllocateIn<Alloc = Fixed<'a>>,
30    A: Allocator,
31{
32    type Alloc = Spill<'a, A>;
33
34    #[inline]
35    fn allocate_in(self, layout: Layout) -> Result<(NonNull<[u8]>, Self::Alloc), AllocError> {
36        match self.buffer.allocate_in(layout) {
37            Ok((ptr, fixed)) => {
38                let alloc = Spill::new(self.alloc, ptr.as_ptr().cast(), fixed);
39                Ok((ptr, alloc))
40            }
41            Err(_) => {
42                let ptr = self.alloc.allocate(layout)?;
43                let alloc = Spill::new(self.alloc, ptr::null(), Fixed::DEFAULT);
44                Ok((ptr, alloc))
45            }
46        }
47    }
48}
flex_alloc/storage/spill.rs

flex_alloc/storage/
spill.rs
