net_util: Implement FromStr for MacAddr

This allows it to be used with str::parse().

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

net_util/src/mac.rs

@@ -9,6 +9,7 @@ use rand::Rng;
 use std::fmt;
 use std::io;
 use std::result::Result;
+use std::str::FromStr;
 
 use serde::de::{Deserialize, Deserializer, Error};
 use serde::ser::{Serialize, Serializer};
@@ -120,6 +121,18 @@ impl<'de> Deserialize<'de> for MacAddr {
     }
 }
 
+pub enum MacAddrParseError {
+    InvalidValue(String),
+}
+
+impl FromStr for MacAddr {
+    type Err = MacAddrParseError;
+
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        MacAddr::parse_str(s).map_err(|_| MacAddrParseError::InvalidValue(s.to_owned()))
+    }
+}
+
 #[cfg(test)]
 mod tests {
     extern crate serde_json;