Implement disk space sensor

src/sensors/disk.rs

@@ -0,0 +1,28 @@
+use super::Sensor;
+use std::process::Command;
+
+pub struct DiskSensor {
+    mount: String
+}
+
+impl DiskSensor {
+    pub fn new(mount: &str) -> DiskSensor {
+        DiskSensor { mount: mount.to_string() }
+    }
+}
+
+impl Sensor for DiskSensor {
+    fn status(&mut self) -> String {
+        let output = Command::new("df")
+          .arg("--output=avail")
+          .arg("-h")
+          .arg(&self.mount)
+          .output()
+          .ok()
+          .expect("Could not run df");
+
+        let output = String::from_utf8_lossy(&output.stdout);
+        let space = output.lines().nth(1).expect("Could not get space");
+        space.trim().to_string()
+    }
+}

src/sensors/mod.rs

@@ -1,4 +1,5 @@
 mod battery;
+mod disk;
 mod time;
 mod temperature;
 
@@ -7,6 +8,7 @@ use comm::Channel;
 use config::Config;
 use std::thread;
 use self::battery::BatterySensor;
+use self::disk::DiskSensor;
 use self::temperature::TempSensor;
 use self::time::TimeSensor;
 
@@ -20,6 +22,7 @@ pub fn sensors(tx: &Channel, config: &Config) {
 
 
     let mut sensors: Vec<Box<Sensor>> = vec![
+        Box::new(DiskSensor::new("/")),
         Box::new(TempSensor::new(zone)),
         Box::new(TimeSensor::new("UTC %H:%M", true)),
         Box::new(TimeSensor::new("%Y-%m-%d %H:%M", false))