iceoryx2_pal_testing/memory.rs
1// Copyright (c) 2024 Contributors to the Eclipse Foundation
2//
3// See the NOTICE file(s) distributed with this work for additional
4// information regarding copyright ownership.
5//
6// This program and the accompanying materials are made available under the
7// terms of the Apache Software License 2.0 which is available at
8// https://www.apache.org/licenses/LICENSE-2.0, or the MIT license
9// which is available at https://opensource.org/licenses/MIT.
10//
11// SPDX-License-Identifier: Apache-2.0 OR MIT
12
13use alloc::alloc::{alloc, dealloc};
14use core::alloc::Layout;
15
16/// Allocates uninitialized memory on the heap. When it goes out of scope the memory is released.
17/// The user has to ensure that the memory is initialized.
18pub struct RawMemory<T> {
19 memory: *mut T,
20}
21
22impl<T> Drop for RawMemory<T> {
23 fn drop(&mut self) {
24 unsafe { dealloc(self.memory.cast(), Layout::new::<T>()) }
25 }
26}
27
28impl<T> RawMemory<T> {
29 /// Allocates memory to fit in a T and fills the memory with values provided by the fill
30 /// callback.
31 pub fn new<F: FnMut(usize) -> u8>(mut fill: F) -> Self {
32 let layout = Layout::new::<T>();
33 let memory = unsafe { alloc(layout) };
34
35 for i in 0..layout.size() {
36 unsafe { memory.add(i).write(fill(i)) }
37 }
38
39 Self {
40 memory: memory.cast(),
41 }
42 }
43
44 /// Allocates zeroed memory to fit in a T.
45 pub fn new_zeroed() -> Self {
46 Self::new(|_| 0u8)
47 }
48
49 /// Allocates memory filled with a given value to fit in a T.
50 pub fn new_filled(value: u8) -> Self {
51 Self::new(|_| value)
52 }
53
54 /// Returns a const pointer to T
55 pub fn as_ptr(&self) -> *const T {
56 self.memory
57 }
58
59 /// Returns a mutable pointer to T
60 pub fn as_mut_ptr(&self) -> *mut T {
61 self.memory
62 }
63
64 /// Returns a const reference to T
65 ///
66 /// # Safety
67 ///
68 /// * T must have been constructed manually before calling this function.
69 pub unsafe fn assume_init(&self) -> &T {
70 unsafe { &*self.memory }
71 }
72
73 /// Returns a mutable reference to T
74 ///
75 /// # Safety
76 ///
77 /// * T must have been constructed manually before calling this function.
78 pub unsafe fn assume_init_mut(&mut self) -> &mut T {
79 unsafe { &mut *self.memory }
80 }
81
82 /// Returns a slice to the underlying memory
83 pub fn as_slice(&self) -> &[u8] {
84 unsafe { core::slice::from_raw_parts(self.memory.cast(), core::mem::size_of::<T>()) }
85 }
86
87 /// Returns a mutable slice to the underlying memory
88 pub fn as_slice_mut(&mut self) -> &mut [u8] {
89 unsafe { core::slice::from_raw_parts_mut(self.memory.cast(), core::mem::size_of::<T>()) }
90 }
91}