63 lines
1.6 KiB
Rust
63 lines
1.6 KiB
Rust
#![feature(allocator)]
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#![feature(const_fn)]
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#![allocator]
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#![no_std]
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use spin::Mutex;
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use linked_list_allocator::Heap;
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extern crate spin;
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extern crate linked_list_allocator;
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static HEAP: Mutex<Option<Heap>> = Mutex::new(None);
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pub unsafe fn init(offset: usize, size: usize) {
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*HEAP.lock() = Some(Heap::new(offset, size));
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}
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#[no_mangle]
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pub extern fn __rust_allocate(size: usize, align: usize) -> *mut u8 {
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if let Some(ref mut heap) = *HEAP.lock() {
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heap.allocate_first_fit(size, align).expect("out of memory")
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} else {
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panic!("__rust_allocate: heap not initialized");
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}
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}
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#[no_mangle]
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pub extern fn __rust_deallocate(ptr: *mut u8, size: usize, align: usize) {
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if let Some(ref mut heap) = *HEAP.lock() {
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unsafe { heap.deallocate(ptr, size, align) };
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} else {
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panic!("__rust_deallocate: heap not initialized");
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}
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}
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#[no_mangle]
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pub extern fn __rust_usable_size(size: usize, _align: usize) -> usize {
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size
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}
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#[no_mangle]
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pub extern fn __rust_reallocate_inplace(_ptr: *mut u8, size: usize,
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_new_size: usize, _align: usize) -> usize
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{
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size
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}
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#[no_mangle]
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pub extern fn __rust_reallocate(ptr: *mut u8, size: usize, new_size: usize,
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align: usize) -> *mut u8 {
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use core::{ptr, cmp};
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// from: https://github.com/rust-lang/rust/blob/
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// c66d2380a810c9a2b3dbb4f93a830b101ee49cc2/
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// src/liballoc_system/lib.rs#L98-L101
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let new_ptr = __rust_allocate(new_size, align);
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unsafe { ptr::copy(ptr, new_ptr, cmp::min(size, new_size)) };
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__rust_deallocate(ptr, size, align);
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new_ptr
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}
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