`ulog`

A tiny rust logging library, meant for embedded devices with a very small space budget:

no allocations
no global variables
no synchronization
no std
optional formatting
logging levels, helper macros, helper structs

When (not) to use it

This library is especially useful when:

you don't want a global logger (otherwise see rust-lang/log)
you don't want allocations or synchronization (otherwise see slog-rs/slog)
you want to easily opt out of any kind of formatting

Typical scenarios for using this library include embedded programs with very limited resources, or rust functions called through FFI that may not have access to an allocator or global, mutable variables.

Example

To start using this library, simply implement ULog on the struct responsible with logging:

use ulog::{ULog, ULogData};

struct MyLogger;

impl ULog for MyLogger {
    fn log_begin(&self, log_data: &ULogData) {
        print!("[MyLogger {}]", log_data.level.as_short_str());
    }

    fn log_str(&self, _log_data: &ULogData, string: &str) {
        print!(" {string}");
    }

    fn log_format<T: std::fmt::Debug>(&self, _log_data: &ULogData, key: &str, value: &T) {
        print!(" {key} => {value:?}");
    }

    fn log_end(&self, _log_data: &ULogData) {
        println!("");
    }
}

fn main() {
    let logger = MyLogger;

    ulog::info!(logger, "Hello, this is an info!");

    ulog::error!(logger, "Whoops, something went wrong!", "error_code" => 42);
}

You can also pass &impl ULog in a library or function:

use ulog::ULog;

fn fibonacci(n: u32, logger: &impl ULog) -> u32 {
    ulog::info!(logger, "fibonacci", "step" => n);

    if n <= 0 {
        0
    } else if n == 1 {
        1
    } else {
        fibonacci(n - 1, logger) + fibonacci(n - 2, logger)
    }
}

adri326/ulog

ulog

When (not) to use it

Example

`ulog`