A standalone, #![no_std]-friendly Logger crate. Based on the design of the logger built into the bootloader crate and meant to be used in OS kernels.

To use this crate, specify it as a dependency in your kernel's Cargo.toml, then initialize it.

Initialization

The logger needs to be initialized in order to be used. To do that, one must first create a global instance, using a crate like conquer_once:

pub static PRINTK: OnceCell
   
     = OnceCell::uninit();

   

After this, the log crate needs to be attached to it. This requires the following 3 steps:

1. Use the get_or_init method to unwrap the LockedPrintk object from its outer OnceCell
2. Use log::set_logger to tell the log crate what to attach to
3. Use log::set_max_level to tell the log crate how many levels of logging you want to do

Here's an example function demonstrating how this is done in pure Rust:

pub fn printk_init(buffer: &'static mut [u8], info: FrameBufferInfo) {
    let kernel_logger = printk::PRINTK.get_or_init(move || printk::LockedPrintk::new(buffer, info));
    log::set_logger(kernel_logger).expect("logger already set");
    log::set_max_level(log::LevelFilter::Trace);
    log::info!("Hello, Kernel!");
}

Contributing

If you have any functionality to add, feel free to create a pull request. I'll gladly test and accept it. Also, if you have any bugs to report, that is also what GitHub is for.