Go to file
Bradlee Speice 2e5af84607 Update Cargo.toml 2019-01-01 15:48:43 -05:00
examples Renaming and a new macro 2018-12-06 23:02:44 -05:00
qadapt-macro Update Cargo.toml 2019-01-01 15:48:43 -05:00
qadapt-spin Update Cargo.toml 2019-01-01 15:48:43 -05:00
src Use the system allocator 2018-12-16 16:29:25 -05:00
tests Add an async demonstration 2018-12-08 18:05:46 -05:00
.gitignore Use new CI template 2018-12-02 22:42:29 -05:00
.travis.yml Re-enable rustfmt 2018-12-16 23:34:16 -05:00
CHANGELOG.md Update the changelog for 1.0.1 2019-01-01 14:23:14 -05:00
CONTRIBUTING.md Use new CI template 2018-12-02 22:42:29 -05:00
CONTRIBUTORS.md Use new CI template 2018-12-02 22:42:29 -05:00
Cargo.toml Update Cargo.toml 2019-01-01 15:48:43 -05:00
LICENSE Use new CI template 2018-12-02 22:42:29 -05:00
Makefile Prepare for 1.0 2018-12-15 16:12:06 -05:00
README.md Prepare for 1.0 2018-12-15 16:12:06 -05:00
appveyor.yml Using system allocator doesn't change CircleCI being able to run 2019-01-01 11:23:28 -05:00
rustfmt.toml Use new CI template 2018-12-02 22:42:29 -05:00

README.md

qadapt

crates.io docs.rs codecov travisci appveyor


debug_assert! for your memory usage

This allocator is a helper for writing high-performance code that is memory-sensitive; a thread panic will be triggered if a function annotated with #[no_alloc], or code inside an assert_no_alloc! macro interacts with the allocator in any way. Wanton allocations and unforeseen drops no more - this library lets you focus on writing code without worrying if Rust properly managed to inline the variable into the stack.

Now, an allocator blowing up in production is a scary thought; that's why QADAPT is designed to strip its own code out whenever you're running with a release build. Just like the debug_assert! macro in Rust's standard library, it's safe to use without worrying about a unforeseen circumstance causing your application to crash.

Usage

Actually making use of QADAPT is straight-forward. To set up the allocator, place the following snippet in either your program binaries (main.rs) or tests:

use qadapt::QADAPT;

#[global_allocator]
static Q: QADAPT = QADAPT;

After that, there are two ways of telling QADAPT that it should trigger a panic:

  1. Annotate functions with the #[no_alloc] proc macro:
use qadapt::no_alloc;

// This function is fine, there are no allocations here
#[no_alloc]
fn do_math() -> u8 {
    2 + 2
}

// This function will trigger a panic when called
#[no_alloc]
fn does_panic() -> Box<u32> {
    Box::new(5)
}

fn main() {
    do_math();
    does_panic();
}
  1. Evaluate expressions with the assert_no_alloc! macro
use qadapt::assert_no_alloc;

fn do_work() {
    // This code is allowed to trigger an allocation
    let b = Box::new(8);
    
    // This code would panic if an allocation occurred inside it
    let x = assert_no_alloc!(*b + 2);
    assert_eq!(x, 10);
}