perf(alsa): reduce playback wakeups via cpal buffer tuning

src-tauri/vendor/cpal/build.rs

@@ -0,0 +1,14 @@
+use std::env;
+
+const CPAL_ASIO_DIR: &str = "CPAL_ASIO_DIR";
+
+fn main() {
+    println!("cargo:rerun-if-env-changed={}", CPAL_ASIO_DIR);
+
+    // If ASIO directory isn't set silently return early
+    // otherwise set the asio config flag
+    match env::var(CPAL_ASIO_DIR) {
+        Err(_) => {}
+        Ok(_) => println!("cargo:rustc-cfg=asio"),
+    };
+}