ASIO: open control panel

asio-sys/build.rs

@@ -64,6 +64,7 @@ fn main() {
     // Print out links to needed libraries
     println!("cargo:rustc-link-lib=dylib=ole32");
     println!("cargo:rustc-link-lib=dylib=user32");
+    println!("cargo:rustc-link-lib=dylib=Advapi32");
     println!("cargo:rustc-link-search={}", out_dir.display());
     println!("cargo:rustc-link-lib=static=asio");
     println!("cargo:rustc-cfg=asio");
@@ -218,6 +219,7 @@ fn create_bindings(cpal_asio_dir: &PathBuf) {
         .allowlist_function("ASIOStart")
         .allowlist_function("ASIOStop")
         .allowlist_function("ASIODisposeBuffers")
+        .allowlist_function("ASIOControlPanel")
         .allowlist_function("ASIOExit")
         .allowlist_function("load_asio_driver")
         .allowlist_function("remove_current_driver")

asio-sys/src/bindings/mod.rs

@@ -777,6 +777,10 @@ impl Driver {
         let mut mcb = MESSAGE_CALLBACKS.lock().unwrap();
         mcb.retain(|&(id, _)| id != rem_id);
     }
+
+    pub fn open_control_panel(&self) -> Result<(), AsioError> {
+        unsafe { asio_result!(ai::ASIOControlPanel()) }
+    }
 }
 
 impl DriverState {

examples/asio_panel.rs

@@ -0,0 +1,45 @@
+#[cfg(all(windows, feature = "asio"))]
+fn main() -> anyhow::Result<()> {
+    use cpal::platform::asio::AsioDeviceExt;
+    use cpal::traits::{DeviceTrait, HostTrait, StreamTrait};
+    use cpal::HostId;
+
+    let host = cpal::host_from_id(HostId::Asio)?;
+
+    let device = host
+        .default_output_device()
+        .ok_or_else(|| anyhow::anyhow!("No ASIO device found"))?;
+
+    println!(
+        "Opening control panel for: {}",
+        device.description()?.name()
+    );
+
+    let config = device.default_output_config()?;
+
+    let err_fn = move |err| println!("Stream Error: {:?}", err);
+
+    let stream = device.build_output_stream(
+        &config.config(),
+        move |_data: &mut [i32], _: &cpal::OutputCallbackInfo| { /* play silence */ },
+        err_fn,
+        None,
+    )?;
+
+    stream.play()?;
+
+    // This is a blocking call on some devices, so spawn it in its own thread.
+    std::thread::spawn(move || {
+        if let Err(e) = device.asio_open_control_panel() {
+            eprintln!("Could not open panel: {:?}", e);
+        }
+    });
+
+    // Keep the thread alive so the window doesn't close immediately
+    std::thread::sleep(std::time::Duration::from_secs(5));
+
+    Ok(())
+}
+
+#[cfg(not(all(windows, feature = "asio")))]
+fn main() {}

src/platform/asio.rs

@@ -0,0 +1,24 @@
+use crate::platform::DeviceInner;
+use crate::BackendSpecificError;
+use crate::Device;
+
+pub trait AsioDeviceExt {
+    fn asio_open_control_panel(&self) -> Result<(), BackendSpecificError>;
+}
+
+impl AsioDeviceExt for Device {
+    fn asio_open_control_panel(&self) -> Result<(), BackendSpecificError> {
+        if let DeviceInner::Asio(ref asio_device) = self.as_inner() {
+            asio_device
+                .driver
+                .open_control_panel()
+                .map_err(|e| BackendSpecificError {
+                    description: format!("Failed to open control panel: {:?}", e),
+                })
+        } else {
+            Err(BackendSpecificError {
+                description: "Not an ASIO device".to_string(),
+            })
+        }
+    }
+}

src/platform/mod.rs

@@ -10,6 +10,9 @@ pub use self::platform_impl::*;
 #[cfg(feature = "custom")]
 pub use crate::host::custom::{Device as CustomDevice, Host as CustomHost, Stream as CustomStream};
 
+#[cfg(all(target_os = "windows", feature = "asio"))]
+pub mod asio;
+
 /// A macro to assist with implementing a platform's dynamically dispatched [`Host`] type.
 ///
 /// These dynamically dispatched types are necessary to allow for users to switch between hosts at