Full Code of rust-embedded/embedded-alloc for AI

Repository: rust-embedded/embedded-alloc
Branch: master
Commit: 13c18de83178
Files: 21
Total size: 51.6 KB

Directory structure:
gitextract_10arganv/

├── .cargo/
│   └── config.toml
├── .github/
│   ├── CODEOWNERS
│   └── workflows/
│       └── ci.yml
├── .gitignore
├── CHANGELOG.md
├── CODE_OF_CONDUCT.md
├── Cargo.toml
├── LICENSE-APACHE
├── LICENSE-MIT
├── README.md
├── examples/
│   ├── allocator_api.rs
│   ├── exhaustion.rs
│   ├── global_alloc.rs
│   ├── llff_integration_test.rs
│   ├── tlsf_integration_test.rs
│   └── track_usage.rs
├── memory.x
├── qemu-runner.sh
└── src/
    ├── lib.rs
    ├── llff.rs
    └── tlsf.rs

================================================
FILE CONTENTS
================================================

================================================
FILE: .cargo/config.toml
================================================
[build]
# Common embedded build targets
target = "thumbv7em-none-eabihf"
# target = "thumbv6m-none-eabi"

[target.thumbv7em-none-eabihf]
# used to run the qemu_test.rs example with QEMU
runner = "./qemu-runner.sh --target thumbv7em-none-eabihf"
rustflags = [
  "-Clink-arg=-Tlink.x",
  "-Clink-arg=-Tdefmt.x",
  # Can be useful for debugging and to inspect where the heap memory is placed/linked.
  # "-Clink-args=-Map=app.map"
]

[target.thumbv6m-none-eabi]
# used to run the qemu_test.rs example with QEMU
runner = "./qemu-runner.sh --target thumbv6m-none-eabi"
rustflags = [
  "-Clink-arg=-Tlink.x",
  "-Clink-arg=-Tdefmt.x",
]

[env]
DEFMT_LOG="info"


================================================
FILE: .github/CODEOWNERS
================================================
* @rust-embedded/libs


================================================
FILE: .github/workflows/ci.yml
================================================
on:
  pull_request: # Run CI for PRs on any branch
  merge_group: # Run CI for the GitHub merge queue
  workflow_dispatch: # Run CI when manually requested
  schedule:
    # Run every week at 8am UTC Saturday
    - cron: '0 8 * * SAT'

name: Continuous integration

jobs:
  check:
    runs-on: ubuntu-latest
    env: {"RUSTFLAGS": "-D warnings"}
    strategy:
      matrix:
        target:
          - thumbv6m-none-eabi
          - thumbv7em-none-eabihf
        toolchain:
          - stable
          - nightly

    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@master
        with:
          targets: ${{ matrix.target }}
          toolchain: ${{ matrix.toolchain }}
      - run: cargo check --target=${{ matrix.target }} --example global_alloc
      - if: ${{ matrix.toolchain == 'nightly' }}
        run: cargo check --target=${{ matrix.target }} --examples --all-features
      - uses: imjohnbo/issue-bot@v3
        if: |
          failure()
          && github.event_name == 'schedule'
        with:
          title: CI Failure
          labels: ci
          body: |
            Scheduled CI run failed. Details:
            https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@master
        with:
          targets: thumbv7em-none-eabihf
          toolchain: nightly
      - name: Install QEMU
        run: |
          sudo apt update
          sudo apt install qemu-system-arm
      - run: qemu-system-arm --version
      - run: cargo +nightly run --target thumbv7em-none-eabihf --example llff_integration_test --all-features
      - run: cargo +nightly run --target thumbv7em-none-eabihf --example tlsf_integration_test --all-features

  clippy:
    name: Clippy
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@nightly
        with:
          components: clippy
          toolchain: nightly
          targets: thumbv6m-none-eabi
      - run: cargo clippy --all-features --examples --target=thumbv6m-none-eabi -- --deny warnings

  format:
    name: Format
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@nightly
        with:
          components: rustfmt
      - run: cargo fmt -- --check

  rustdoc:
    name: rustdoc
    runs-on: ubuntu-latest
    env: {"RUSTDOCFLAGS": "-D warnings"}
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@nightly
        with:
          targets: thumbv7em-none-eabihf
          toolchain: nightly
      - name: rustdoc
        run: cargo +nightly rustdoc --all-features


================================================
FILE: .gitignore
================================================
target
Cargo.lock


================================================
FILE: CHANGELOG.md
================================================
# Change Log

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](http://keepachangelog.com/)
and this project adheres to [Semantic Versioning](http://semver.org/).

## [Unreleased]

### Fixed

- Fix panic in `tlsf::Heap::used`.
- Fix panic in `tlsf::Heap::free` in case the value returned from `insert_free_block_ptr`
  does not cover the full memory range passed in.

## [v0.7.0] - 2026-01-03

### Added

- Added a `init` macro to make initialization easier.
- Added `Heap::free` and `Heap::used` for the TLSF heap.

### Changed

- The `Heap::init` methods now panic if they're called more than once or with `size == 0`.

## [v0.6.0] - 2024-09-01

### Added

- Added a Two-Level Segregated Fit heap with the `tlsf` feature.

### Changed

- The `Heap` struct has been renamed to `LlffHeap` and requires the `llff` feature.
- Updated the rust edition from 2018 to 2021.

## [v0.5.1] - 2023-11-04

### Added

- Implemented [`Allocator`] for `Heap` with the `allocator_api` crate feature.
  This feature requires a nightly toolchain for the unstable [`allocator_api`]
  compiler feature.

[`Allocator`]: https://doc.rust-lang.org/core/alloc/trait.Allocator.html
[`allocator_api`]: https://doc.rust-lang.org/beta/unstable-book/library-features/allocator-api.html

### Changed

- Updated `linked_list_allocator` dependency to 0.10.5, which allows
  compiling with stable rust.

## [v0.5.0] - 2022-12-06

### Changed

- Renamed crate from `alloc-cortex-m` to `embedded-alloc`.
- Renamed `CortexMHeap` to `Heap`.
- Use `critical-section` to lock the heap, instead of `cortex_m::interrupt::free()`.
  This allows using this crate on non-Cortex-M systems, or on
  Cortex-M systems that require a custom critical section implementation.

## [v0.4.3] - 2022-11-03

### Changed

- Updated `linked_list_allocator` dependency to 0.10.4, which fixes
  CVE-2022-36086/RUSTSEC-2022-0063.

## [v0.4.2] - 2022-01-04

### Changed

- Updated `cortex-m` dependency to 0.7.2.

## [v0.4.1] - 2021-01-02

### Added

- `const_mut_refs` feature to the dependency `linked_list_allocator` crate.

### Changed

- Bumped the dependency of the `linked_list_allocator` crate to v0.8.11.

## [v0.4.0] - 2020-06-05

- Bumped the `cortex-m` dependency to v0.6.2.
- Bumped the dependency of the `linked_list_allocator` crate to v0.8.1.
- Removed `#![feature(alloc)]` to supress compiler warning about stability for alloc.

## [v0.3.5] - 2018-06-19

### Fixed

- To work with recent nightly

## [v0.3.4] - 2018-05-12

### Changed

- Update the example in the crate level documentation to show how to define the new `oom` lang item.

## [v0.3.3] - 2018-04-23

- Bumped the dependency of the `linked_list_allocator` crate to v0.6.0.

## [v0.3.2] - 2018-02-26

### Changed

- Bumped the dependency of the `linked_list_allocator` crate to v0.5.0.

## [v0.3.1] - 2017-10-07

### Fixed

- The example in the documentation.

## [v0.3.0] - 2017-10-07

### Changed

- [breaking-change] Switched to the new allocator system. See documentation for details.

## [v0.2.2] - 2017-04-29

### Added

- a `__rust_allocate_zeroed` symbol as it's needed on recent nightlies.

## [v0.2.1] - 2016-11-27

### Fixed

- The heap size is `end_addr` - `start_addr`. Previously, it was wrongly
  calculated as `end_addr - start_addr - 1`.

## [v0.2.0] - 2016-11-19

### Changed

- [breaking-change] Hid the HEAP variable. We now only expose an `init` function to
  initialize the allocator.

## v0.1.0 - 2016-11-19

### Added

- Initial version of the allocator

[Unreleased]: https://github.com/rust-embedded/embedded-alloc/compare/v0.7.0...HEAD
[v0.7.0]: https://github.com/rust-embedded/embedded-alloc/compare/v0.6.0...v0.7.0
[v0.6.0]: https://github.com/rust-embedded/embedded-alloc/compare/v0.5.1...v0.6.0
[v0.5.1]: https://github.com/rust-embedded/embedded-alloc/compare/v0.5.0...v0.5.1
[v0.5.0]: https://github.com/rust-embedded/embedded-alloc/compare/v0.4.3...v0.5.0
[v0.4.3]: https://github.com/rust-embedded/embedded-alloc/compare/v0.4.2...v0.4.3
[v0.4.2]: https://github.com/rust-embedded/embedded-alloc/compare/v0.4.1...v0.4.2
[v0.4.1]: https://github.com/rust-embedded/embedded-alloc/compare/v0.4.0...v0.4.1
[v0.4.0]: https://github.com/rust-embedded/embedded-alloc/compare/v0.3.5...v0.4.0
[v0.3.5]: https://github.com/rust-embedded/embedded-alloc/compare/v0.3.4...v0.3.5
[v0.3.4]: https://github.com/rust-embedded/embedded-alloc/compare/v0.3.3...v0.3.4
[v0.3.3]: https://github.com/rust-embedded/embedded-alloc/compare/v0.3.2...v0.3.3
[v0.3.2]: https://github.com/rust-embedded/embedded-alloc/compare/v0.3.1...v0.3.2
[v0.3.1]: https://github.com/rust-embedded/embedded-alloc/compare/v0.3.0...v0.3.1
[v0.3.0]: https://github.com/rust-embedded/embedded-alloc/compare/v0.2.2...v0.3.0
[v0.2.2]: https://github.com/rust-embedded/embedded-alloc/compare/v0.2.1...v0.2.2
[v0.2.1]: https://github.com/rust-embedded/embedded-alloc/compare/v0.2.0...v0.2.1
[v0.2.0]: https://github.com/rust-embedded/embedded-alloc/compare/v0.1.0...v0.2.0


================================================
FILE: CODE_OF_CONDUCT.md
================================================
# The Rust Code of Conduct

## Conduct

**Contact**: [Libs team](https://github.com/rust-embedded/wg#the-libs-team)

* We are committed to providing a friendly, safe and welcoming environment for all, regardless of level of experience, gender identity and expression, sexual orientation, disability, personal appearance, body size, race, ethnicity, age, religion, nationality, or other similar characteristic.
* On IRC, please avoid using overtly sexual nicknames or other nicknames that might detract from a friendly, safe and welcoming environment for all.
* Please be kind and courteous. There's no need to be mean or rude.
* Respect that people have differences of opinion and that every design or implementation choice carries a trade-off and numerous costs. There is seldom a right answer.
* Please keep unstructured critique to a minimum. If you have solid ideas you want to experiment with, make a fork and see how it works.
* We will exclude you from interaction if you insult, demean or harass anyone. That is not welcome behavior. We interpret the term "harassment" as including the definition in the [Citizen Code of Conduct](http://citizencodeofconduct.org/); if you have any lack of clarity about what might be included in that concept, please read their definition. In particular, we don't tolerate behavior that excludes people in socially marginalized groups.
* Private harassment is also unacceptable. No matter who you are, if you feel you have been or are being harassed or made uncomfortable by a community member, please contact one of the channel ops or any of the [Libs team][team] immediately. Whether you're a regular contributor or a newcomer, we care about making this community a safe place for you and we've got your back.
* Likewise any spamming, trolling, flaming, baiting or other attention-stealing behavior is not welcome.

## Moderation

These are the policies for upholding our community's standards of conduct.

1. Remarks that violate the Rust standards of conduct, including hateful, hurtful, oppressive, or exclusionary remarks, are not allowed. (Cursing is allowed, but never targeting another user, and never in a hateful manner.)
2. Remarks that moderators find inappropriate, whether listed in the code of conduct or not, are also not allowed.
3. Moderators will first respond to such remarks with a warning.
4. If the warning is unheeded, the user will be "kicked," i.e., kicked out of the communication channel to cool off.
5. If the user comes back and continues to make trouble, they will be banned, i.e., indefinitely excluded.
6. Moderators may choose at their discretion to un-ban the user if it was a first offense and they offer the offended party a genuine apology.
7. If a moderator bans someone and you think it was unjustified, please take it up with that moderator, or with a different moderator, **in private**. Complaints about bans in-channel are not allowed.
8. Moderators are held to a higher standard than other community members. If a moderator creates an inappropriate situation, they should expect less leeway than others.

In the Rust community we strive to go the extra step to look out for each other. Don't just aim to be technically unimpeachable, try to be your best self. In particular, avoid flirting with offensive or sensitive issues, particularly if they're off-topic; this all too often leads to unnecessary fights, hurt feelings, and damaged trust; worse, it can drive people away from the community entirely.

And if someone takes issue with something you said or did, resist the urge to be defensive. Just stop doing what it was they complained about and apologize. Even if you feel you were misinterpreted or unfairly accused, chances are good there was something you could've communicated better — remember that it's your responsibility to make your fellow Rustaceans comfortable. Everyone wants to get along and we are all here first and foremost because we want to talk about cool technology. You will find that people will be eager to assume good intent and forgive as long as you earn their trust.

The enforcement policies listed above apply to all official embedded WG venues; including official IRC channels (#rust-embedded); GitHub repositories under rust-embedded; and all forums under rust-embedded.org (forum.rust-embedded.org).

*Adapted from the [Node.js Policy on Trolling](http://blog.izs.me/post/30036893703/policy-on-trolling) as well as the [Contributor Covenant v1.3.0](https://www.contributor-covenant.org/version/1/3/0/).*

[team]: https://github.com/rust-embedded/wg#the-libs-team


================================================
FILE: Cargo.toml
================================================
[package]
authors = [
    "The Cortex-M Team <cortex-m@teams.rust-embedded.org>",
    "Jonathan Pallant <github@thejpster.org.uk>",
    "Jorge Aparicio <jorge@japaric.io>",
    "Sébastien Béchet <sebastien.bechet@osinix.com>",
]

description = "A heap allocator for embedded systems"
repository = "https://github.com/rust-embedded/embedded-alloc"
documentation = "https://docs.rs/embedded-alloc"
readme = "README.md"
edition = "2021"

keywords = [
    "allocator",
    "embedded",
    "arm",
    "riscv",
    "cortex-m",
]
license = "MIT OR Apache-2.0"
name = "embedded-alloc"
version = "0.7.0"

[features]
default = ["llff", "tlsf"]
allocator_api = []

# Use the Two-Level Segregated Fit allocator
tlsf = ["rlsf", "const-default"]
# Use the LinkedList first-fit allocator
llff = ["linked_list_allocator"]

[dependencies]
critical-section = "1.0"
linked_list_allocator = { version = "0.10.5", default-features = false, optional = true }
rlsf = { version = "0.2.1", default-features = false, features = ["unstable"], optional = true }
const-default = { version = "1.0.0", default-features = false, optional = true }

[dev-dependencies]
cortex-m = { version = "0.7.6", features = ["critical-section-single-core"] }
cortex-m-rt = "0.7"
defmt = "1.0"
defmt-semihosting = "0.3.0"
semihosting = { version = "0.1.20", features = ["stdio"] }

# thumbv6m-none-eabi only
[target.thumbv6m-none-eabi.dev-dependencies]
portable-atomic = { version = "1", features = ["unsafe-assume-single-core"] }

# every other target gets the crate without the feature
[target.'cfg(not(target = "thumbv6m-none-eabi"))'.dev-dependencies]
portable-atomic = { version = "1" }

[[example]]
name = "allocator_api"
required-features = ["allocator_api", "llff"]

[[example]]
name = "llff_integration_test"
required-features = ["allocator_api", "llff"]

[[example]]
name = "tlsf_integration_test"
required-features = ["allocator_api", "tlsf"]

[[example]]
name = "global_alloc"
required-features = ["llff"]


================================================
FILE: LICENSE-APACHE
================================================
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================================================
FILE: LICENSE-MIT
================================================
Copyright (c) 2016-2018 Jorge Aparicio

Permission is hereby granted, free of charge, to any
person obtaining a copy of this software and associated
documentation files (the "Software"), to deal in the
Software without restriction, including without
limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software
is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice
shall be included in all copies or substantial portions
of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.


================================================
FILE: README.md
================================================
[![crates.io](https://img.shields.io/crates/d/embedded-alloc.svg)](https://crates.io/crates/embedded-alloc)
[![crates.io](https://img.shields.io/crates/v/embedded-alloc.svg)](https://crates.io/crates/embedded-alloc) -
 [Documentation](https://docs.rs/embedded-alloc) - [Change log](https://github.com/rust-embedded/embedded-alloc/blob/master/CHANGELOG.md)

# `embedded-alloc`

> A heap allocator for embedded systems.

This project is developed and maintained by the [libs team][team].

## Example

```rust
#![no_std]
#![no_main]

extern crate alloc;

use cortex_m_rt::entry;
use embedded_alloc::LlffHeap as Heap;

#[global_allocator]
static HEAP: Heap = Heap::empty();

#[entry]
fn main() -> ! {
    // Initialize the allocator BEFORE you use it
    unsafe {
        embedded_alloc::init!(HEAP, 1024);
    }
    // Alternatively, you can write the code directly to meet specific requirements.
    {
        use core::mem::MaybeUninit;
        const HEAP_SIZE: usize = 1024;
        static mut HEAP_MEM: [MaybeUninit<u8>; HEAP_SIZE] = [MaybeUninit::uninit(); HEAP_SIZE];
        unsafe { HEAP.init(&raw mut HEAP_MEM as usize, HEAP_SIZE) }
    }

    // now the allocator is ready types like Box, Vec can be used.

    loop { /* .. */ }
}
```

For a full usage example, see [`examples/global_alloc.rs`](https://github.com/rust-embedded/embedded-alloc/blob/master/examples/global_alloc.rs).

For this to work, an implementation of [`critical-section`](https://github.com/rust-embedded/critical-section) must be provided.

For simple use cases with Cortex-M CPUs you may enable the `critical-section-single-core` feature in the [cortex-m](https://github.com/rust-embedded/cortex-m) crate.
Please refer to the documentation of [`critical-section`](https://docs.rs/critical-section) for further guidance.

## Features

There are two heaps available to use:

* `llff`: Provides `LlffHeap`, a Linked List First Fit heap.
* `tlsf`: Provides `TlsfHeap`, a Two-Level Segregated Fit heap.

The best heap to use will depend on your application, see [#78](https://github.com/rust-embedded/embedded-alloc/pull/78) for more discussion.

## License

Licensed under either of

- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
  <http://www.apache.org/licenses/LICENSE-2.0>)
- MIT license ([LICENSE-MIT](LICENSE-MIT) or <http://opensource.org/licenses/MIT>)

at your option.

### Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.

## Code of Conduct

Contribution to this crate is organized under the terms of the [Rust Code of
Conduct][CoC], the maintainer of this crate, the [libs team][team], promises
to intervene to uphold that code of conduct.

[CoC]: CODE_OF_CONDUCT.md
[team]: https://github.com/rust-embedded/wg#the-libs-team


================================================
FILE: examples/allocator_api.rs
================================================
//! This examples requires nightly for the allocator API.
#![feature(allocator_api)]
#![no_std]
#![no_main]

extern crate alloc;

use core::{mem::MaybeUninit, panic::PanicInfo};
use cortex_m as _;
use cortex_m_rt::entry;
use defmt_semihosting as _;
use embedded_alloc::LlffHeap as Heap;

// This is not used, but as of 2023-10-29 allocator_api cannot be used without
// a global heap
#[global_allocator]
static HEAP: Heap = Heap::empty();

#[entry]
fn main() -> ! {
    const HEAP_SIZE: usize = 16;
    static mut HEAP_MEM: [MaybeUninit<u8>; HEAP_SIZE] = [MaybeUninit::uninit(); HEAP_SIZE];
    let heap: Heap = Heap::empty();
    unsafe { heap.init(&raw mut HEAP_MEM as usize, HEAP_SIZE) }

    let mut vec = alloc::vec::Vec::new_in(heap);
    vec.push(1);

    defmt::info!("Allocated vector: {:?}", vec.as_slice());

    semihosting::process::exit(0);
}

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    defmt::error!("{}", info);
    semihosting::process::exit(-1);
}


================================================
FILE: examples/exhaustion.rs
================================================
//! Example which shows behavior on pool exhaustion. It simply panics.
#![no_std]
#![no_main]

extern crate alloc;

use cortex_m as _;
use cortex_m_rt::entry;
use defmt::Debug2Format;
use defmt_semihosting as _;

use core::panic::PanicInfo;
use embedded_alloc::TlsfHeap as Heap;

#[global_allocator]
static HEAP: Heap = Heap::empty();

#[entry]
fn main() -> ! {
    // Initialize the allocator BEFORE you use it
    unsafe {
        embedded_alloc::init!(HEAP, 16);
    }

    let _vec = alloc::vec![0; 16];

    defmt::error!("unexpected vector allocation success");

    // Panic is expected here.
    semihosting::process::exit(-1);
}

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    defmt::warn!("received expected heap exhaustion panic");
    defmt::warn!("{}: {}", info, Debug2Format(&info.message()));
    semihosting::process::exit(0);
}


================================================
FILE: examples/global_alloc.rs
================================================
#![no_std]
#![no_main]

extern crate alloc;

use cortex_m as _;
use cortex_m_rt::entry;
use defmt_semihosting as _;

use core::panic::PanicInfo;
// Linked-List First Fit Heap allocator (feature = "llff")
use embedded_alloc::LlffHeap as Heap;
// Two-Level Segregated Fit Heap allocator (feature = "tlsf")
// use embedded_alloc::TlsfHeap as Heap;

#[global_allocator]
static HEAP: Heap = Heap::empty();

#[entry]
fn main() -> ! {
    // Initialize the allocator BEFORE you use it
    unsafe {
        embedded_alloc::init!(HEAP, 1024);
    }

    let vec = alloc::vec![1];

    defmt::info!("Allocated vector: {:?}", vec.as_slice());

    let string = alloc::string::String::from("Hello, world!");

    defmt::info!("Allocated string: {:?}", string.as_str());

    semihosting::process::exit(0);
}

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    defmt::error!("{}", info);
    semihosting::process::exit(-1);
}


================================================
FILE: examples/llff_integration_test.rs
================================================
//! This is a very basic smoke test that runs in QEMU
//! Reference the QEMU section of the [Embedded Rust Book] for more information
//!
//! This only tests integration of the allocator on an embedded target.
//! Comprehensive allocator tests are located in the allocator dependency.
//!
//! After toolchain installation this test can be run with:
//!
//! ```bash
//! cargo +nightly run --target thumbv7m-none-eabi --example llff_integration_test --all-features
//! ```
//!
//! [Embedded Rust Book]: https://docs.rust-embedded.org/book/intro/index.html

#![feature(allocator_api)]
#![no_main]
#![no_std]

extern crate alloc;

use alloc::vec::Vec;
use core::{
    mem::{size_of, MaybeUninit},
    panic::PanicInfo,
};
use cortex_m as _;
use cortex_m_rt::entry;
use defmt_semihosting as _;
use embedded_alloc::LlffHeap as Heap;

#[global_allocator]
static HEAP: Heap = Heap::empty();

fn test_global_heap() {
    assert_eq!(HEAP.used(), 0);

    let mut xs: Vec<i32> = alloc::vec![1];
    xs.push(2);
    xs.extend(&[3, 4]);

    // do not optimize xs
    core::hint::black_box(&mut xs);

    assert_eq!(xs.as_slice(), &[1, 2, 3, 4]);
    assert_eq!(HEAP.used(), size_of::<i32>() * xs.len());
}

fn test_allocator_api() {
    // small local heap
    const HEAP_SIZE: usize = 16;
    let mut heap_mem: [MaybeUninit<u8>; HEAP_SIZE] = [MaybeUninit::uninit(); HEAP_SIZE];
    let local_heap: Heap = Heap::empty();
    unsafe { local_heap.init(&raw mut heap_mem as usize, HEAP_SIZE) }

    assert_eq!(local_heap.used(), 0);

    let mut v: Vec<u16, Heap> = Vec::new_in(local_heap);
    v.push(0xCAFE);
    v.extend(&[0xDEAD, 0xFEED]);

    // do not optimize v
    core::hint::black_box(&mut v);

    assert_eq!(v.as_slice(), &[0xCAFE, 0xDEAD, 0xFEED]);
}

pub type TestTable<'a> = &'a [(fn() -> (), &'static str)];

#[entry]
fn main() -> ! {
    unsafe {
        embedded_alloc::init!(HEAP, 1024);
    }

    let tests: TestTable = &[
        (test_global_heap, "test_global_heap"),
        (test_allocator_api, "test_allocator_api"),
    ];

    for (test_fn, test_name) in tests {
        defmt::info!("{}: start", test_name);
        test_fn();
        defmt::info!("{}: pass", test_name);
    }

    // exit QEMU with a success status
    semihosting::process::exit(0);
}

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    defmt::error!("{}", info);
    semihosting::process::exit(-1);
}


================================================
FILE: examples/tlsf_integration_test.rs
================================================
//! This is a very basic smoke test that runs in QEMU
//! Reference the QEMU section of the [Embedded Rust Book] for more information
//!
//! This only tests integration of the allocator on an embedded target.
//! Comprehensive allocator tests are located in the allocator dependency.
//!
//! After toolchain installation this test can be run with:
//!
//! ```bash
//! cargo +nightly run --target thumbv7m-none-eabi --example tlsf_integration_test --all-features
//! ```
//!
//! [Embedded Rust Book]: https://docs.rust-embedded.org/book/intro/index.html

#![feature(allocator_api)]
#![no_main]
#![no_std]

extern crate alloc;
use defmt_semihosting as _;

use alloc::collections::LinkedList;
use core::{mem::MaybeUninit, panic::PanicInfo};
use cortex_m as _;
use cortex_m_rt::entry;
use embedded_alloc::TlsfHeap as Heap;

#[global_allocator]
static HEAP: Heap = Heap::empty();
const HEAP_SIZE: usize = 30 * 1024;

pub type TestTable<'a> = &'a [(fn() -> (), &'static str)];

fn test_global_heap() {
    const ELEMS: usize = 250;
    assert_eq!(HEAP_SIZE, HEAP.free() + HEAP.used());
    let initial_free = HEAP.free();

    let mut allocated = LinkedList::new();
    for _ in 0..ELEMS {
        allocated.push_back(0);
    }
    for i in 0..ELEMS {
        allocated.push_back(i as i32);
    }

    assert_eq!(allocated.len(), 2 * ELEMS);

    for _ in 0..ELEMS {
        allocated.pop_front();
    }

    for i in 0..ELEMS {
        assert_eq!(allocated.pop_front().unwrap(), i as i32);
    }
    assert_eq!(HEAP_SIZE, HEAP.free() + HEAP.used());
    assert_eq!(initial_free, HEAP.free());
}

fn test_allocator_api() {
    // small local heap
    const HEAP_SIZE: usize = 256;
    let mut heap_mem: [MaybeUninit<u8>; HEAP_SIZE] = [MaybeUninit::uninit(); HEAP_SIZE];
    let local_heap: Heap = Heap::empty();
    unsafe { local_heap.init(heap_mem.as_mut_ptr() as usize, HEAP_SIZE) }

    const ELEMS: usize = 2;

    let mut allocated = LinkedList::new_in(local_heap);
    for _ in 0..ELEMS {
        allocated.push_back(0);
    }
    for i in 0..ELEMS {
        allocated.push_back(i as i32);
    }

    assert_eq!(allocated.len(), 2 * ELEMS);

    for _ in 0..ELEMS {
        allocated.pop_front();
    }

    for i in 0..ELEMS {
        assert_eq!(allocated.pop_front().unwrap(), i as i32);
    }
}

#[entry]
fn main() -> ! {
    unsafe {
        embedded_alloc::init!(HEAP, HEAP_SIZE);
    }

    let tests: TestTable = &[
        (test_global_heap, "test_global_heap"),
        (test_allocator_api, "test_allocator_api"),
    ];

    for (test_fn, test_name) in tests {
        defmt::info!("{}: start", test_name);
        test_fn();
        defmt::info!("{}: pass", test_name);
    }

    // exit QEMU with a success status
    semihosting::process::exit(0);
}

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    defmt::error!("{}", info);
    semihosting::process::exit(-1);
}


================================================
FILE: examples/track_usage.rs
================================================
#![no_std]
#![no_main]

extern crate alloc;

use cortex_m as _;
use cortex_m_rt::entry;
use defmt::Debug2Format;
use defmt_semihosting as _;

use core::{mem::MaybeUninit, panic::PanicInfo};
use embedded_alloc::TlsfHeap as Heap;
//use embedded_alloc::LlffHeap as Heap;

#[global_allocator]
static HEAP: Heap = Heap::empty();

#[entry]
fn main() -> ! {
    // Initialize the allocator BEFORE you use it
    const HEAP_SIZE: usize = 4096;
    static mut HEAP_MEM: [MaybeUninit<u8>; HEAP_SIZE] = [MaybeUninit::uninit(); HEAP_SIZE];
    unsafe { HEAP.init(&raw mut HEAP_MEM as usize, HEAP_SIZE) }

    let mut alloc_vecs = alloc::vec::Vec::new();
    let mut free_memory = HEAP_SIZE;
    // Keep allocating until we are getting low on memory. It doesn't have to end in a panic.
    while free_memory > 512 {
        defmt::info!(
            "{} of {} heap memory allocated so far...",
            HEAP_SIZE - free_memory,
            HEAP_SIZE
        );
        let new_vec = alloc::vec![1_u8; 64];
        alloc_vecs.push(new_vec);
        free_memory = HEAP.free();
    }

    drop(alloc_vecs);

    defmt::info!(
        "{} of {} heap memory are allocated after drop",
        HEAP_SIZE - HEAP.free(),
        HEAP_SIZE
    );

    semihosting::process::exit(0);
}

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    defmt::error!("{}: {}", info, Debug2Format(&info.message()));
    semihosting::process::exit(-1);
}


================================================
FILE: memory.x
================================================
MEMORY
{
  /* These values correspond to the LM3S6965, one of the few devices QEMU can emulate */
  FLASH : ORIGIN = 0x00000000, LENGTH = 256K
  RAM : ORIGIN = 0x20000000, LENGTH = 64K
}


================================================
FILE: qemu-runner.sh
================================================
#!/bin/bash

# This requires you to previously run `cargo install defmt-print`

# See https://ferroussystems.hackmd.io/@jonathanpallant/ryA1S6QDJx for a description of all the relevant QEMU machines
TARGET=""
ELF_BINARY=""

# very small argument parser
while [[ $# -gt 0 ]]; do
    case "$1" in
        --target)   TARGET="$2"; shift 2 ;;
        *)          ELF_BINARY="$1"; shift ;;
    esac
done

# default to the target cargo is currently building for
TARGET="${TARGET:-thumbv7em-none-eabihf}"

case "$TARGET" in
    thumbv6m-none-eabi)
        MACHINE="-cpu cortex-m3 -machine mps2-an385" ;;
    thumbv7em-none-eabihf)
        # All suitable for thumbv7em-none-eabihf
        MACHINE="-cpu cortex-m4 -machine mps2-an386" ;;
        # MACHINE="-cpu cortex-m7 -machine mps2-387" ;;
        # MACHINE="-cpu cortex-m7 -machine mps2-500"
    *)
        echo "Unsupported target: $TARGET" >&2
        exit 1 ;;
esac

LOG_FORMAT='{[{L}]%bold} {s} {({ff}:{l:1})%dimmed}'

echo "Running on '$MACHINE'..."
echo "------------------------------------------------------------------------"
qemu-system-arm $MACHINE -semihosting-config enable=on,target=native -nographic -kernel $ELF_BINARY | defmt-print -e $ELF_BINARY --log-format="$LOG_FORMAT"
echo "------------------------------------------------------------------------"


================================================
FILE: src/lib.rs
================================================
#![doc = include_str!("../README.md")]
#![no_std]
#![cfg_attr(feature = "allocator_api", feature(allocator_api))]
#![warn(missing_docs)]

#[cfg(feature = "llff")]
mod llff;
#[cfg(feature = "tlsf")]
mod tlsf;

#[cfg(feature = "llff")]
pub use llff::Heap as LlffHeap;
#[cfg(feature = "tlsf")]
pub use tlsf::Heap as TlsfHeap;

/// Initialize the global heap.
///
/// This macro creates a static, uninitialized memory buffer of the specified size and
/// initializes the heap instance with that buffer.
///
/// # Parameters
///
/// - `$heap:ident`: The identifier of the global heap instance to initialize.
/// - `$size:expr`: An expression evaluating to a `usize` that specifies the size of the
///   static memory buffer in bytes. It must be **greater than zero**.
///
/// # Safety
///
/// This macro must be called first, before any operations on the heap, and **only once**.
/// It internally calls `Heap::init(...)` on the heap,
/// so `Heap::init(...)` should not be called directly if this macro is used.
///
/// # Panics
///
/// This macro will panic if either of the following are true:
///
/// - this function is called more than ONCE.
/// - `size == 0`.
///
/// # Example
///
/// ```rust
/// use cortex_m_rt::entry;
/// use embedded_alloc::LlffHeap as Heap;
///
/// #[global_allocator]
/// static HEAP: Heap = Heap::empty();
///
/// #[entry]
/// fn main() -> ! {
///     // Initialize the allocator BEFORE you use it
///     unsafe {
///         embedded_alloc::init!(HEAP, 1024);
///     }
///     let mut xs = Vec::new();
///     // ...
/// }
/// ```
#[macro_export]
macro_rules! init {
    ($heap:ident, $size:expr) => {
        static mut HEAP_MEM: [::core::mem::MaybeUninit<u8>; $size] =
            [::core::mem::MaybeUninit::uninit(); $size];
        $heap.init(&raw mut HEAP_MEM as usize, $size)
    };
}


================================================
FILE: src/llff.rs
================================================
use core::alloc::{GlobalAlloc, Layout};
use core::cell::RefCell;
use core::ptr::{self, NonNull};

use critical_section::Mutex;
use linked_list_allocator::Heap as LLHeap;

/// A linked list first fit heap.
pub struct Heap {
    heap: Mutex<RefCell<(LLHeap, bool)>>,
}

impl Heap {
    /// Create a new UNINITIALIZED heap allocator
    ///
    /// You must initialize this heap using the
    /// [`init`](Self::init) method before using the allocator.
    pub const fn empty() -> Heap {
        Heap {
            heap: Mutex::new(RefCell::new((LLHeap::empty(), false))),
        }
    }

    /// Initializes the heap
    ///
    /// This function must be called BEFORE you run any code that makes use of the
    /// allocator.
    ///
    /// `start_addr` is the address where the heap will be located.
    ///
    /// `size` is the size of the heap in bytes.
    ///
    /// Note that:
    ///
    /// - The heap grows "upwards", towards larger addresses. Thus `start_addr` will
    ///   be the smallest address used.
    ///
    /// - The largest address used is `start_addr + size - 1`, so if `start_addr` is
    ///   `0x1000` and `size` is `0x30000` then the allocator won't use memory at
    ///   addresses `0x31000` and larger.
    ///
    /// # Safety
    ///
    /// This function is safe if the following invariants hold:
    ///
    /// - `start_addr` points to valid memory.
    /// - `size` is correct.
    ///
    /// # Panics
    ///
    /// This function will panic if either of the following are true:
    ///
    /// - this function is called more than ONCE.
    /// - `size == 0`.
    pub unsafe fn init(&self, start_addr: usize, size: usize) {
        assert!(size > 0);
        critical_section::with(|cs| {
            let mut heap = self.heap.borrow_ref_mut(cs);
            assert!(!heap.1);
            heap.1 = true;
            heap.0.init(start_addr as *mut u8, size);
        });
    }

    /// Returns an estimate of the amount of bytes in use.
    pub fn used(&self) -> usize {
        critical_section::with(|cs| self.heap.borrow_ref_mut(cs).0.used())
    }

    /// Returns an estimate of the amount of bytes available.
    pub fn free(&self) -> usize {
        critical_section::with(|cs| self.heap.borrow_ref_mut(cs).0.free())
    }

    fn alloc(&self, layout: Layout) -> Option<NonNull<u8>> {
        critical_section::with(|cs| {
            self.heap
                .borrow_ref_mut(cs)
                .0
                .allocate_first_fit(layout)
                .ok()
        })
    }

    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
        critical_section::with(|cs| {
            self.heap
                .borrow_ref_mut(cs)
                .0
                .deallocate(NonNull::new_unchecked(ptr), layout)
        });
    }
}

unsafe impl GlobalAlloc for Heap {
    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
        self.alloc(layout)
            .map_or(ptr::null_mut(), |allocation| allocation.as_ptr())
    }

    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
        self.dealloc(ptr, layout);
    }
}

#[cfg(feature = "allocator_api")]
mod allocator_api {
    use super::*;
    use core::alloc::{AllocError, Allocator};

    unsafe impl Allocator for Heap {
        fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> {
            match layout.size() {
                0 => Ok(NonNull::slice_from_raw_parts(layout.dangling_ptr(), 0)),
                size => self.alloc(layout).map_or(Err(AllocError), |allocation| {
                    Ok(NonNull::slice_from_raw_parts(allocation, size))
                }),
            }
        }

        unsafe fn deallocate(&self, ptr: NonNull<u8>, layout: Layout) {
            if layout.size() != 0 {
                self.dealloc(ptr.as_ptr(), layout);
            }
        }
    }
}


================================================
FILE: src/tlsf.rs
================================================
use core::alloc::{GlobalAlloc, Layout};
use core::cell::RefCell;
use core::ptr::{self, NonNull};

use const_default::ConstDefault;
use critical_section::Mutex;
use rlsf::Tlsf;

type TlsfHeap = Tlsf<'static, usize, usize, { usize::BITS as usize }, { usize::BITS as usize }>;

struct Inner {
    tlsf: TlsfHeap,
    initialized: bool,
    raw_block: Option<NonNull<[u8]>>,
    raw_block_size: usize,
}

// Safety: The whole inner type is wrapped by a [Mutex].
unsafe impl Sync for Inner {}
unsafe impl Send for Inner {}

/// A two-Level segregated fit heap.
pub struct Heap {
    heap: Mutex<RefCell<Inner>>,
}

impl Heap {
    /// Create a new UNINITIALIZED heap allocator
    ///
    /// You must initialize this heap using the
    /// [`init`](Self::init) method before using the allocator.
    pub const fn empty() -> Heap {
        Heap {
            heap: Mutex::new(RefCell::new(Inner {
                tlsf: ConstDefault::DEFAULT,
                initialized: false,
                raw_block: None,
                raw_block_size: 0,
            })),
        }
    }

    /// Initializes the heap
    ///
    /// This function must be called BEFORE you run any code that makes use of the
    /// allocator.
    ///
    /// `start_addr` is the address where the heap will be located.
    ///
    /// `size` is the size of the heap in bytes.
    ///
    /// Note that:
    ///
    /// - The heap grows "upwards", towards larger addresses. Thus `start_addr` will
    ///   be the smallest address used.
    ///
    /// - The largest address used is `start_addr + size - 1`, so if `start_addr` is
    ///   `0x1000` and `size` is `0x30000` then the allocator won't use memory at
    ///   addresses `0x31000` and larger.
    ///
    /// # Safety
    ///
    /// This function is safe if the following invariants hold:
    ///
    /// - `start_addr` points to valid memory.
    /// - `size` is correct.
    ///
    /// # Panics
    ///
    /// This function will panic if either of the following are true:
    ///
    /// - this function is called more than ONCE.
    /// - `size`, after aligning start and end to `rlsf::GRANULARITY`, is smaller than `rlsf::GRANULARITY * 2`.
    pub unsafe fn init(&self, start_addr: usize, size: usize) {
        assert!(size > 0);
        critical_section::with(|cs| {
            let mut heap = self.heap.borrow_ref_mut(cs);
            assert!(!heap.initialized);
            let block: NonNull<[u8]> =
                NonNull::slice_from_raw_parts(NonNull::new_unchecked(start_addr as *mut u8), size);
            let Some(actual_size) = heap.tlsf.insert_free_block_ptr(block) else {
                panic!("Allocation too small for heap");
            };
            let block: NonNull<[u8]> = NonNull::slice_from_raw_parts(
                NonNull::new_unchecked(start_addr as *mut u8),
                actual_size.get(),
            );
            heap.initialized = true;
            heap.raw_block = Some(block);
            heap.raw_block_size = size;
        });
    }

    fn alloc(&self, layout: Layout) -> Option<NonNull<u8>> {
        critical_section::with(|cs| self.heap.borrow_ref_mut(cs).tlsf.allocate(layout))
    }

    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
        critical_section::with(|cs| {
            self.heap
                .borrow_ref_mut(cs)
                .tlsf
                .deallocate(NonNull::new_unchecked(ptr), layout.align())
        })
    }

    unsafe fn realloc(&self, ptr: *mut u8, new_layout: Layout) -> Option<NonNull<u8>> {
        critical_section::with(|cs| {
            self.heap
                .borrow_ref_mut(cs)
                .tlsf
                .reallocate(NonNull::new_unchecked(ptr), new_layout)
        })
    }

    /// Get the amount of bytes used by the allocator.
    pub fn used(&self) -> usize {
        critical_section::with(|cs| {
            let free = self.free_with_cs(cs);
            self.heap.borrow_ref_mut(cs).raw_block_size - free
        })
    }

    /// Get the amount of free bytes in the allocator.
    pub fn free(&self) -> usize {
        critical_section::with(|cs| self.free_with_cs(cs))
    }

    fn free_with_cs(&self, cs: critical_section::CriticalSection) -> usize {
        let inner_mut = self.heap.borrow_ref_mut(cs);
        if !inner_mut.initialized {
            return 0;
        }
        // Safety: We pass the memory block we previously initialized the heap with
        // to the `iter_blocks` method.
        unsafe {
            inner_mut
                .tlsf
                .iter_blocks(inner_mut.raw_block.unwrap())
                .filter(|block_info| !block_info.is_occupied())
                .map(|block_info| block_info.max_payload_size())
                .sum::<usize>()
        }
    }
}

unsafe impl GlobalAlloc for Heap {
    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
        self.alloc(layout)
            .map_or(ptr::null_mut(), |allocation| allocation.as_ptr())
    }

    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
        self.dealloc(ptr, layout)
    }

    unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 {
        // SAFETY: `layout.align()` is a power of two, and the size precondition
        // is upheld by the caller.
        let new_layout =
            unsafe { core::alloc::Layout::from_size_align_unchecked(new_size, layout.align()) };
        self.realloc(ptr, new_layout)
            .map_or(ptr::null_mut(), |allocation| allocation.as_ptr())
    }
}

#[cfg(feature = "allocator_api")]
mod allocator_api {
    use super::*;
    use core::alloc::{AllocError, Allocator};

    unsafe impl Allocator for Heap {
        fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> {
            match layout.size() {
                0 => Ok(NonNull::slice_from_raw_parts(layout.dangling_ptr(), 0)),
                size => self.alloc(layout).map_or(Err(AllocError), |allocation| {
                    Ok(NonNull::slice_from_raw_parts(allocation, size))
                }),
            }
        }

        unsafe fn deallocate(&self, ptr: NonNull<u8>, layout: Layout) {
            if layout.size() != 0 {
                self.dealloc(ptr.as_ptr(), layout);
            }
        }
    }
}