FrozenCore

Custom implementations and core utilities for frozen codebases.

Index

• ff
• fm
• fe
• hints
• notes

FrozenFile

FF is a custom implementation of std::fs::File.

To use the ff module, add it as a dependency in your Cargo.toml:

[dependencies]
frozen-core = { version = "0.0.2", features = ["ff"] }

FF is currently available for following platforms,

Example usage,

use frozen_core::ff::{FF, FFCfg};

const MODULE_ID: u8 = 1;

fn main() {
    let path = "/tmp/example/data.bin".into();
    let ff = FF::new(FFCfg::new(path, MODULE_ID), 16).expect("create");

    let data = 42u64.to_le_bytes();
    ff.write(data.as_ptr(), 0, data.len()).expect("write");
    ff.sync().expect("sync");

    let mut buf = [0u8; 8];
    ff.read(buf.as_mut_ptr(), 0, buf.len()).expect("read");

    assert_eq!(u64::from_le_bytes(buf), 42);
}

FrozenMMap

FM is a custom implementation of mmap.

To use the fm module, add it as a dependency in your Cargo.toml:

[dependencies]
frozen-core = { version = "0.0.2", features = ["fm"] }

FM is currently available for following platforms,

Example usage,

use frozen_core::fm::{FM, FMCfg};
use frozen_core::ff::{FF, FFCfg};

const MODULE_ID: u8 = 1;

fn main() {
    let path = "/tmp/example/data.bin".into();
    let ff = FF::new(FFCfg::new(path, MODULE_ID), 8).expect("file");
    let fm = FM::new(ff.fd(), 8, FMCfg::new(MODULE_ID)).expect("mmap");

    {
        let w = fm.writer::<u64>(0).expect("writer");
        w.write(|v| *v = 0xDEADBEEF).expect("write");
    }

    fm.sync().expect("sync");

    let r = fm.reader::<u64>(0).expect("reader");
    let value = r.read(|v| *v);

    assert_eq!(value, 0xDEADBEEF);
}

FrozenError

FRes & FErr are custom implementation's for result and error propogation.

The fe module is available by deafult. Add it as a dependency in your Cargo.toml:

[dependencies]
frozen-core = "0.0.2"

Hints

The hints module provides stable friendly implementations of likely and unlikely branch hints functions.

The hints module is available by deafult. Add it as a dependency in your Cargo.toml:

[dependencies]
frozen-core = "0.0.2"

Example usage,

use frozen_core::hints::{likely, unlikely};

fn main() {
    let enabled = true;
    let values = [1, 2, 3, -1, 4];

    // Hot configuration path
    if likely(enabled) {
        fast_path();
    }

    // Hot loop with rare error case
    for v in values {
        if unlikely(v < 0) {
            continue; // rare invalid value
        }
        process(v);
    }
}

#[inline]
fn fast_path() {
    // expected fast path
}

#[inline]
fn process(_v: i32) {
    // normal processing
}

Notes

[!IMPORTANT] frozen-core is primarily created for frozen-lab projects. External use is discouraged, but not prohibited, given you asume all the risks.

This project is licensed under the Apache-2.0 and MIT License. See the LICENSE-APACHE and LICENSE-MIT file for more details.

Contributions are welcome! Please feel free to submit a PR or open an issue if you have any feedback or suggestions.