[](https://crates.io/crates/embedded-alloc)
[](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