artiq/artiq/firmware/runtime/logger.rs

94 lines
3.0 KiB
Rust

use core::{mem, ptr};
use core::cell::{Cell, RefCell};
use log::{self, Log, LogLevel, LogMetadata, LogRecord, LogLevelFilter};
use log_buffer::LogBuffer;
use board;
pub struct BufferLogger {
buffer: RefCell<LogBuffer<&'static mut [u8]>>,
trace_to_uart: Cell<bool>
}
unsafe impl Sync for BufferLogger {}
static mut LOGGER: *const BufferLogger = ptr::null();
impl BufferLogger {
pub fn new(buffer: &'static mut [u8]) -> BufferLogger {
BufferLogger {
buffer: RefCell::new(LogBuffer::new(buffer)),
trace_to_uart: Cell::new(true)
}
}
pub fn register<F: FnOnce()>(&self, f: F) {
// log::set_logger_raw captures a pointer to ourselves, so we must prevent
// ourselves from being moved or dropped after that function is called (and
// before log::shutdown_logger_raw is called).
unsafe {
log::set_logger_raw(|max_log_level| {
max_log_level.set(LogLevelFilter::Trace);
self as *const Log
}).expect("global logger can only be initialized once");
LOGGER = self;
}
f();
log::shutdown_logger_raw().unwrap();
unsafe {
LOGGER = ptr::null();
}
}
pub fn with_instance<R, F: FnOnce(&BufferLogger) -> R>(f: F) -> R {
f(unsafe { mem::transmute::<*const BufferLogger, &BufferLogger>(LOGGER) })
}
pub fn clear(&self) {
borrow_mut!(self.buffer).clear()
}
pub fn extract<R, F: FnOnce(&str) -> R>(&self, f: F) -> R {
f(borrow_mut!(self.buffer).extract())
}
pub fn disable_trace_to_uart(&self) {
if self.trace_to_uart.get() {
trace!("disabling tracing to UART; all further trace messages \
are sent to core log only");
self.trace_to_uart.set(false)
}
}
}
impl Log for BufferLogger {
fn enabled(&self, _metadata: &LogMetadata) -> bool {
true
}
fn log(&self, record: &LogRecord) {
if self.enabled(record.metadata()) {
let force_uart = match self.buffer.try_borrow_mut() {
Ok(mut buffer) => {
use core::fmt::Write;
writeln!(buffer, "[{:12}us] {:>5}({}): {}",
board::clock::get_us(), record.level(),
record.target(), record.args()).unwrap();
false
}
Err(_) => {
// we're trying to log something while sending the log somewhere,
// probably over the network. just let it go to UART.
true
}
};
// Printing to UART is really slow, so avoid doing that when we have an alternative
// route to retrieve the debug messages.
if self.trace_to_uart.get() || record.level() <= LogLevel::Info || force_uart {
println!("[{:12}us] {:>5}({}): {}",
board::clock::get_us(), record.level(), record.target(), record.args());
}
}
}
}