58 lines
1.2 KiB
Rust
58 lines
1.2 KiB
Rust
//! How to use the heap and a dynamic memory allocator
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//!
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//! This example depends on the alloc-cortex-m crate so you'll have to add it to your Cargo.toml:
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//!
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//! ``` text
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//! # or edit the Cargo.toml file manually
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//! $ cargo add alloc-cortex-m
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//! ```
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//!
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//! ---
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#![feature(alloc)]
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#![feature(alloc_error_handler)]
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#![no_main]
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#![no_std]
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extern crate alloc;
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extern crate panic_halt;
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use self::alloc::vec;
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use core::alloc::Layout;
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use alloc_cortex_m::CortexMHeap;
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use cortex_m::asm;
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use cortex_m_rt::entry;
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use cortex_m_semihosting::hprintln;
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// this is the allocator the application will use
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#[global_allocator]
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static ALLOCATOR: CortexMHeap = CortexMHeap::empty();
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const HEAP_SIZE: usize = 1024; // in bytes
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#[entry]
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fn main() -> ! {
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// Initialize the allocator BEFORE you use it
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unsafe { ALLOCATOR.init(cortex_m_rt::heap_start() as usize, HEAP_SIZE) }
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// Growable array allocated on the heap
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let xs = vec![0, 1, 2];
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hprintln!("{:?}", xs).unwrap();
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// exit QEMU
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// NOTE do not run this on hardware; it can corrupt OpenOCD state
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debug::exit(debug::EXIT_SUCCESS);
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loop {}
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}
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// define what happens in an Out Of Memory (OOM) condition
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#[alloc_error_handler]
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fn alloc_error(_layout: Layout) -> ! {
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asm::bkpt();
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loop {}
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}
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