Implement device enumeration for WASAPI driver backend

Cargo.toml

@@ -20,6 +20,26 @@ cfg_aliases = "0.2.1"
 [target.'cfg(any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd", target_os = "netbsd"))'.dependencies]
 alsa = "0.9.0"
 
+[target.'cfg(target_os = "windows")'.dependencies]
+windows = { version = "0.58.0", features = [
+    "Win32_Media_Audio",
+    "Win32_Foundation",
+    "Win32_Devices_Properties",
+    "Win32_Media_KernelStreaming",
+    "Win32_System_Com_StructuredStorage",
+    "Win32_System_Threading",
+    "Win32_Security",
+    "Win32_System_SystemServices",
+    "Win32_System_Variant",
+    "Win32_Media_Multimedia",
+    "Win32_UI_Shell_PropertiesSystem"
+]}
+
 [[example]]
 name = "enumerate_alsa"
 path = "examples/enumerate_alsa.rs"
+
+[[example]]
+name = "enumerate_wasapi"
+path = "examples/enumerate_wasapi.rs"
+

build.rs

@@ -5,6 +5,7 @@ fn main() {
     cfg_aliases! {
         wasm: { any(target_os = "wasm32") },
         os_alsa: { any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd",
-            target_os = "netbsd") }
+            target_os = "netbsd") },
+        os_wasapi: { target_os = "windows" }
     }
 }

examples/enumerate_alsa.rs

@@ -1,9 +1,7 @@
-use std::error::Error;
-
 mod util;
 
 #[cfg(os_alsa)]
-fn main() -> Result<(), Box<dyn Error>> {
+fn main() -> Result<(), Box<dyn std::error::Error>> {
     use crate::util::enumerate::enumerate_devices;
     use interflow::backends::alsa::AlsaDriver;
     enumerate_devices(AlsaDriver::default())
@@ -13,4 +11,3 @@ fn main() -> Result<(), Box<dyn Error>> {
 fn main() {
     println!("ALSA driver is not available on this platform");
 }
-

examples/enumerate_wasapi.rs

@@ -0,0 +1,13 @@
+mod util;
+
+#[cfg(os_wasapi)]
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    use crate::util::enumerate::enumerate_devices;
+    use interflow::backends::wasapi::WasapiDriver;
+    enumerate_devices(WasapiDriver)
+}
+
+#[cfg(not(os_wasapi))]
+fn main() {
+    println!("WASAPI driver is not available on this platform");
+}

examples/sine_wave.rs

@@ -13,13 +13,15 @@ fn main() -> Result<()> {
     };
     assert!(device.is_config_supported(&config));
     println!("Using device {}", device.name());
-    let stream = device.create_output_stream(
-        config,
-        SineWave {
-            frequency: 440.,
-            phase: 0.,
-        },
-    ).unwrap();
+    let stream = device
+        .create_output_stream(
+            config,
+            SineWave {
+                frequency: 440.,
+                phase: 0.,
+            },
+        )
+        .unwrap();
     println!("Press Enter to stop");
     std::io::stdin().read_line(&mut String::new())?;
     stream.eject().unwrap();
@@ -33,7 +35,10 @@ struct SineWave {
 
 impl AudioOutputCallback for SineWave {
     fn on_output_data(&mut self, context: AudioCallbackContext, mut output: AudioOutput<f32>) {
-        eprintln!("Callback called, timestamp: {:2.3} s", context.timestamp.as_seconds());
+        eprintln!(
+            "Callback called, timestamp: {:2.3} s",
+            context.timestamp.as_seconds()
+        );
         let sr = context.timestamp.samplerate as f32;
         for i in 0..output.buffer.num_samples() {
             output.buffer.set_mono(i, self.next_sample(sr));

examples/util/enumerate.rs

@@ -1,7 +1,10 @@
 use interflow::{AudioDevice, AudioDriver, DeviceType};
 use std::error::Error;
 
-pub fn enumerate_devices<Driver: AudioDriver>(driver: Driver) -> Result<(), Box<dyn Error>> where <Driver as AudioDriver>::Error: 'static {
+pub fn enumerate_devices<Driver: AudioDriver>(driver: Driver) -> Result<(), Box<dyn Error>>
+where
+    <Driver as AudioDriver>::Error: 'static,
+{
     eprintln!("Driver name   : {}", Driver::DISPLAY_NAME);
     eprintln!("Driver version: {}", driver.version()?);
     eprintln!("Default device");
@@ -19,4 +22,4 @@ pub fn enumerate_devices<Driver: AudioDriver>(driver: Driver) -> Result<(), Box<
         eprintln!("\t{} ({:?})", device.name(), device.device_type());
     }
     Ok(())
-}
+}

examples/util/mod.rs

@@ -1 +1 @@
-pub mod enumerate;
+pub mod enumerate;

src/audio_buffer.rs

@@ -54,7 +54,7 @@ impl<S: DataOwned> Default for AudioBufferBase<S> {
     }
 }
 
-impl<S: Data, S2: Data<Elem=S::Elem>> PartialEq<AudioBufferBase<S2>> for AudioBufferBase<S>
+impl<S: Data, S2: Data<Elem = S::Elem>> PartialEq<AudioBufferBase<S2>> for AudioBufferBase<S>
 where
     S::Elem: PartialEq<S::Elem>,
 {
@@ -178,7 +178,7 @@ impl<S: DataMut> AudioBufferBase<S> {
     pub fn channels_mut(&mut self) -> impl '_ + Iterator<Item = ArrayViewMut1<S::Elem>> {
         self.storage.rows_mut().into_iter()
     }
-    
+
     pub fn as_interleaved_mut(&mut self) -> ArrayViewMut2<S::Elem> {
         self.storage.view_mut().reversed_axes()
     }
@@ -374,11 +374,8 @@ impl<'a, T: Sample> AudioMut<'a, T> {
         }
     }
 
-    pub fn mix(
-        &mut self,
-        other: AudioRef<T>,
-        other_amplitude: T::Float,
-    ) where
+    pub fn mix(&mut self, other: AudioRef<T>, other_amplitude: T::Float)
+    where
         T: AddAssign<T>,
     {
         for (mut ch_a, ch_b) in self.channels_mut().zip(other.channels()) {

src/backends/alsa.rs

@@ -1,21 +1,21 @@
 use core::fmt;
-use std::{borrow::Cow, convert::Infallible, ffi::CStr};
-use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Arc;
 use std::thread::JoinHandle;
 use std::time::Duration;
+use std::{borrow::Cow, convert::Infallible, ffi::CStr};
 
 use alsa::{device_name::HintIter, pcm, PCM};
 use thiserror::Error;
 
+use crate::audio_buffer::{AudioMut, AudioRef};
+use crate::channel_map::{Bitset, ChannelMap32};
+use crate::timestamp::Timestamp;
 use crate::{
     AudioCallbackContext, AudioDevice, AudioDriver, AudioInput, AudioInputCallback,
     AudioInputDevice, AudioOutput, AudioOutputCallback, AudioOutputDevice, AudioStreamHandle,
     Channel, DeviceType, StreamConfig,
 };
-use crate::audio_buffer::{AudioMut, AudioRef};
-use crate::channel_map::{Bitset, ChannelMap32};
-use crate::timestamp::Timestamp;
 
 #[derive(Debug, Error)]
 #[error("ALSA error: ")]
@@ -236,7 +236,7 @@ impl<Callback: 'static + Send + AudioInputCallback> AlsaStream<Callback> {
                     let input = AudioInput { buffer, timestamp };
                     callback.on_input_data(context, input);
                     timestamp += frames as u64;
-                    
+
                     match device.pcm.state() {
                         pcm::State::Suspended => {
                             if hwp.can_resume() {

src/backends/mod.rs

@@ -1,11 +1,18 @@
-use crate::{AudioDevice, AudioDriver, AudioInputDevice, AudioOutputCallback, AudioOutputDevice, DeviceType};
+use crate::{
+    AudioDevice, AudioDriver, AudioInputDevice, AudioOutputCallback, AudioOutputDevice, DeviceType,
+};
 
 #[cfg(os_alsa)]
 pub mod alsa;
 
+#[cfg(os_wasapi)]
+pub mod wasapi;
+
 pub fn default_driver() -> impl AudioDriver {
     #[cfg(os_alsa)]
-    alsa::AlsaDriver
+    return alsa::AlsaDriver;
+    #[cfg(os_wasapi)]
+    return wasapi::WasapiDriver;
 }
 
 pub fn default_input_device_from<Driver: AudioDriver>(driver: &Driver) -> Driver::Device
@@ -24,7 +31,9 @@ where
 
 pub fn default_input_device() -> impl AudioInputDevice {
     #[cfg(os_alsa)]
-    default_input_device_from(&alsa::AlsaDriver)
+    return default_input_device_from(&alsa::AlsaDriver);
+    #[cfg(os_wasapi)]
+    return default_input_device_from(&wasapi::WasapiDriver);
 }
 
 pub fn default_output_device_from<Driver: AudioDriver>(driver: &Driver) -> Driver::Device
@@ -40,5 +49,7 @@ where
 
 pub fn default_output_device() -> impl AudioOutputDevice {
     #[cfg(os_alsa)]
-    default_output_device_from(&alsa::AlsaDriver)
+    return default_output_device_from(&alsa::AlsaDriver);
+    #[cfg(os_wasapi)]
+    return default_output_device_from(&wasapi::WasapiDriver);
 }