clean up SASL code

src/sasl/mechanisms/plain.rs

@@ -0,0 +1,30 @@
+//! Provides the SASL "PLAIN" mechanism.
+
+use sasl::SaslMechanism;
+
+pub struct Plain {
+    name: String,
+    password: String,
+}
+
+impl Plain {
+    pub fn new<N: Into<String>, P: Into<String>>(name: N, password: P) -> Plain {
+        Plain {
+            name: name.into(),
+            password: password.into(),
+        }
+    }
+}
+
+impl SaslMechanism for Plain {
+    fn name() -> &'static str { "PLAIN" }
+
+    fn initial(&mut self) -> Vec<u8> {
+        let mut auth = Vec::new();
+        auth.push(0);
+        auth.extend(self.name.bytes());
+        auth.push(0);
+        auth.extend(self.password.bytes());
+        auth
+    }
+}