1 files changed, 68 insertions, 0 deletions
diff --git a/src/libcore/rt/logging.rs b/src/libcore/rt/logging.rs
new file mode 100644
index 00000000000..a0d05397689
--- /dev/null
+++ b/src/libcore/rt/logging.rs
@@ -0,0 +1,68 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use either::*;
+
+pub trait Logger {
+    fn log(&mut self, msg: Either<~str, &'static str>);
+}
+
+pub struct StdErrLogger;
+
+impl Logger for StdErrLogger {
+    fn log(&mut self, msg: Either<~str, &'static str>) {
+        use io::{Writer, WriterUtil};
+
+        let s: &str = match msg {
+            Left(ref s) => {
+                let s: &str = *s;
+                s
+            }
+            Right(ref s) => {
+                let s: &str = *s;
+                s
+            }
+        };
+        let dbg = ::libc::STDERR_FILENO as ::io::fd_t;
+        dbg.write_str(s);
+        dbg.write_str("\n");
+        dbg.flush();
+    }
+}
+
+/// Configure logging by traversing the crate map and setting the
+/// per-module global logging flags based on the logging spec
+pub fn init(crate_map: *u8) {
+    use os;
+    use str;
+    use ptr;
+    use option::{Some, None};
+    use libc::c_char;
+
+    let log_spec = os::getenv("RUST_LOG");
+    match log_spec {
+        Some(spec) => {
+            do str::as_c_str(spec) |s| {
+                unsafe {
+                    rust_update_log_settings(crate_map, s);
+                }
+            }
+        }
+        None => {
+            unsafe {
+                rust_update_log_settings(crate_map, ptr::null());
+            }
+        }
+    }
+
+    extern {
+        fn rust_update_log_settings(crate_map: *u8, settings: *c_char);
+    }
+}