vendor/hashbrown-0.11.2/src/raw/alloc.rs

   1 pub(crate) use self::inner::{do_alloc, Allocator, Global};
   2
   3 #[cfg(feature = "nightly")]
   4 mod inner {
   5     use crate::alloc::alloc::Layout;
   6     pub use crate::alloc::alloc::{Allocator, Global};
   7     use core::ptr::NonNull;
   8
   9     #[allow(clippy::map_err_ignore)]
  10     pub fn do_alloc<A: Allocator>(alloc: &A, layout: Layout) -> Result<NonNull<u8>, ()> {
  11         alloc
  12             .allocate(layout)
  13             .map(|ptr| ptr.as_non_null_ptr())
  14             .map_err(|_| ())
  15     }
  16
  17     #[cfg(feature = "bumpalo")]
  18     unsafe impl Allocator for crate::BumpWrapper<'_> {
  19         #[inline]
  20         fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, core::alloc::AllocError> {
  21             match self.0.try_alloc_layout(layout) {
  22                 Ok(ptr) => Ok(NonNull::slice_from_raw_parts(ptr, layout.size())),
  23                 Err(_) => Err(core::alloc::AllocError),
  24             }
  25         }
  26         #[inline]
  27         unsafe fn deallocate(&self, _ptr: NonNull<u8>, _layout: Layout) {}
  28     }
  29 }
  30
  31 #[cfg(not(feature = "nightly"))]
  32 mod inner {
  33     use crate::alloc::alloc::{alloc, dealloc, Layout};
  34     use core::ptr::NonNull;
  35
  36     pub unsafe trait Allocator {
  37         fn allocate(&self, layout: Layout) -> Result<NonNull<u8>, ()>;
  38         unsafe fn deallocate(&self, ptr: NonNull<u8>, layout: Layout);
  39     }
  40
  41     #[derive(Copy, Clone)]
  42     pub struct Global;
  43     unsafe impl Allocator for Global {
  44         #[inline]
  45         fn allocate(&self, layout: Layout) -> Result<NonNull<u8>, ()> {
  46             unsafe { NonNull::new(alloc(layout)).ok_or(()) }
  47         }
  48         #[inline]
  49         unsafe fn deallocate(&self, ptr: NonNull<u8>, layout: Layout) {
  50             dealloc(ptr.as_ptr(), layout)
  51         }
  52     }
  53     impl Default for Global {
  54         #[inline]
  55         fn default() -> Self {
  56             Global
  57         }
  58     }
  59
  60     pub fn do_alloc<A: Allocator>(alloc: &A, layout: Layout) -> Result<NonNull<u8>, ()> {
  61         alloc.allocate(layout)
  62     }
  63
  64     #[cfg(feature = "bumpalo")]
  65     unsafe impl Allocator for crate::BumpWrapper<'_> {
  66         #[allow(clippy::map_err_ignore)]
  67         fn allocate(&self, layout: Layout) -> Result<NonNull<u8>, ()> {
  68             self.0.try_alloc_layout(layout).map_err(|_| ())
  69         }
  70         unsafe fn deallocate(&self, _ptr: NonNull<u8>, _layout: Layout) {}
  71     }
  72 }