Add audio_cache_size to set maximum cache size

src/config.rs

@@ -21,6 +21,7 @@ pub struct ConfigValues {
     pub theme: Option<ConfigTheme>,
     pub use_nerdfont: Option<bool>,
     pub audio_cache: Option<bool>,
+    pub audio_cache_size: Option<u32>,
     pub backend: Option<String>,
     pub backend_device: Option<String>,
     pub volnorm: Option<bool>,

src/spotify.rs

@@ -162,7 +162,9 @@ impl Spotify {
         let cache = Cache::new(
             Some(config::cache_path("librespot")),
             audio_cache_path,
-            None,
+            cfg.values()
+                .audio_cache_size
+                .map(|size| (size * 1048576) as u64),
         )
         .expect("Could not create cache");
         debug!("opening spotify session");