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())

examples/enumerate_wasapi.rs

@@ -0,0 +1,14 @@
+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");
+}
+

src/backends/mod.rs

@@ -1,4 +1,6 @@
-use crate::{AudioDevice, AudioDriver, AudioInputDevice, AudioOutputCallback, AudioOutputDevice, DeviceType};
+use crate::{
+    AudioDevice, AudioDriver, AudioInputDevice, AudioOutputCallback, AudioOutputDevice, DeviceType,
+};
 
 #[cfg(os_alsa)]
 pub mod alsa;
@@ -42,3 +44,5 @@ pub fn default_output_device() -> impl AudioOutputDevice {
     #[cfg(os_alsa)]
     default_output_device_from(&alsa::AlsaDriver)
 }
+#[cfg(os_wasapi)]
+pub mod wasapi;