Add in-memory logging, retrievable from sys:log

src/scheme/sys/log.rs

@@ -0,0 +1,17 @@
+use alloc::vec::Vec;
+
+use log::LOG;
+use syscall::error::Result;
+
+pub fn resource() -> Result<Vec<u8>> {
+    let mut vec = Vec::new();
+
+    if let Some(ref log) = *LOG.lock() {
+        let slices = log.read();
+        vec.reserve_exact(slices.0.len() + slices.1.len());
+        vec.extend_from_slice(slices.0);
+        vec.extend_from_slice(slices.1);
+    }
+
+    Ok(vec)
+}