Rename aster-frame to ostd

ostd/src/logger.rs

@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: MPL-2.0
+
+//! Logging support.
+
+use log::{Level, Metadata, Record};
+
+use crate::early_println;
+
+const LOGGER: Logger = Logger {};
+
+/// The log level.
+///
+/// FIXME: The logs should be able to be read from files in the userspace,
+/// and the log level should be configurable.
+pub const INIT_LOG_LEVEL: Level = Level::Error;
+
+struct Logger {}
+
+impl log::Log for Logger {
+    fn enabled(&self, metadata: &Metadata) -> bool {
+        metadata.level() <= INIT_LOG_LEVEL
+    }
+
+    fn log(&self, record: &Record) {
+        if self.enabled(record.metadata()) {
+            early_println!("[{}]: {}", record.level(), record.args());
+        }
+    }
+
+    fn flush(&self) {}
+}
+
+pub(crate) fn init() {
+    log::set_logger(&LOGGER)
+        .map(|()| log::set_max_level(INIT_LOG_LEVEL.to_level_filter()))
+        .unwrap();
+}