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#![no_std]
#![cfg_attr(not(feature = "stable-rust"), feature(rustc_attrs))]
extern crate loca;
use core::mem::{self, ManuallyDrop};
use core::usize;
pub use loca::*;
extern "Rust" {
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_alloc(size: usize, align: usize, err: *mut u8) -> *mut u8;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
#[cold]
fn __rust_oom(err: *const u8) -> !;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_dealloc(ptr: *mut u8, size: usize, align: usize);
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_usable_size(layout: *const u8, min: *mut usize, max: *mut usize);
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_realloc(ptr: *mut u8,
old_size: usize,
old_align: usize,
new_size: usize,
new_align: usize,
err: *mut u8) -> *mut u8;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_alloc_zeroed(size: usize, align: usize, err: *mut u8) -> *mut u8;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_alloc_excess(size: usize,
align: usize,
excess: *mut usize,
err: *mut u8) -> *mut u8;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_realloc_excess(ptr: *mut u8,
old_size: usize,
old_align: usize,
new_size: usize,
new_align: usize,
excess: *mut usize,
err: *mut u8) -> *mut u8;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_grow_in_place(ptr: *mut u8,
old_size: usize,
old_align: usize,
new_size: usize,
new_align: usize) -> u8;
#[cfg_attr(not(feature = "stable-rust"), rustc_allocator_nounwind)]
fn __rust_shrink_in_place(ptr: *mut u8,
old_size: usize,
old_align: usize,
new_size: usize,
new_align: usize) -> u8;
}
#[derive(Copy, Clone, Default, Debug)]
pub struct Heap;
unsafe impl Alloc for Heap {
#[inline]
unsafe fn alloc(&mut self, layout: Layout) -> Result<*mut u8, AllocErr> {
let mut err = ManuallyDrop::new(mem::uninitialized::<AllocErr>());
let ptr =
__rust_alloc(layout.size(), layout.align(), &mut *err as *mut AllocErr as *mut u8);
if ptr.is_null() { Err(ManuallyDrop::into_inner(err)) } else { Ok(ptr) }
}
#[inline]
#[cold]
fn oom(&mut self, err: AllocErr) -> ! {
unsafe { __rust_oom(&err as *const AllocErr as *const u8) }
}
#[inline]
unsafe fn dealloc(&mut self, ptr: *mut u8, layout: Layout) {
__rust_dealloc(ptr, layout.size(), layout.align())
}
#[inline]
fn usable_size(&self, layout: Layout) -> (usize, usize) {
let mut min = 0;
let mut max = 0;
unsafe {
__rust_usable_size(&layout as *const Layout as *const u8, &mut min, &mut max);
}
(min, max)
}
#[inline]
unsafe fn realloc(&mut self, ptr: *mut u8, layout: Layout, new_layout: Layout)
-> Result<*mut u8, AllocErr> {
let mut err = ManuallyDrop::new(mem::uninitialized::<AllocErr>());
let ptr = __rust_realloc(ptr,
layout.size(),
layout.align(),
new_layout.size(),
new_layout.align(),
&mut *err as *mut AllocErr as *mut u8);
if ptr.is_null() {
Err(ManuallyDrop::into_inner(err))
} else {
mem::forget(err);
Ok(ptr)
}
}
#[inline]
unsafe fn alloc_zeroed(&mut self, layout: Layout) -> Result<*mut u8, AllocErr> {
let mut err = ManuallyDrop::new(mem::uninitialized::<AllocErr>());
let ptr = __rust_alloc_zeroed(layout.size(),
layout.align(),
&mut *err as *mut AllocErr as *mut u8);
if ptr.is_null() { Err(ManuallyDrop::into_inner(err)) } else { Ok(ptr) }
}
#[inline]
unsafe fn alloc_excess(&mut self, layout: Layout) -> Result<Excess, AllocErr> {
let mut err = ManuallyDrop::new(mem::uninitialized::<AllocErr>());
let mut size = 0;
let ptr = __rust_alloc_excess(layout.size(),
layout.align(),
&mut size,
&mut *err as *mut AllocErr as *mut u8);
if ptr.is_null() { Err(ManuallyDrop::into_inner(err)) } else { Ok(Excess(ptr, size)) }
}
#[inline]
unsafe fn realloc_excess(&mut self,
ptr: *mut u8,
layout: Layout,
new_layout: Layout) -> Result<Excess, AllocErr> {
let mut err = ManuallyDrop::new(mem::uninitialized::<AllocErr>());
let mut size = 0;
let ptr = __rust_realloc_excess(ptr,
layout.size(),
layout.align(),
new_layout.size(),
new_layout.align(),
&mut size,
&mut *err as *mut AllocErr as *mut u8);
if ptr.is_null() { Err(ManuallyDrop::into_inner(err)) } else { Ok(Excess(ptr, size)) }
}
#[inline]
unsafe fn resize_in_place(&mut self, ptr: *mut u8, layout: Layout, new_layout: Layout)
-> Result<(), CannotReallocInPlace> {
use ::core::cmp::Ord;
use ::core::cmp::Ordering::*;
debug_assert!(new_layout.align() == layout.align());
if 0 == match Ord::cmp(&new_layout.size(), &layout.size()) {
Greater => __rust_grow_in_place(ptr,
layout.size(),
layout.align(),
new_layout.size(),
new_layout.align()),
Less => __rust_shrink_in_place(ptr,
layout.size(),
layout.align(),
new_layout.size(),
new_layout.align()),
Equal => 1,
} { Err(CannotReallocInPlace) } else { Ok(()) }
}
}
#[cfg(test)]
mod tests {
use ::{Heap, Alloc, Layout};
#[test]
fn allocate_zeroed() {
unsafe {
let layout = Layout::from_size_align(1024, 1).unwrap();
let ptr = Heap.alloc_zeroed(layout.clone()).unwrap_or_else(|e| Heap.oom(e));
let end = ptr.offset(layout.size() as isize);
let mut i = ptr;
while i < end {
assert_eq!(*i, 0);
i = i.offset(1);
}
Heap.dealloc(ptr, layout);
}
}
}