Initial changes for adding visionOS support

.github/workflows/coreaudio-rs.yml

@@ -52,6 +52,30 @@ jobs:
     - name: Build iphonesimulator feedback example
       run: cd examples/ios && xcodebuild ONLY_ACTIVE_ARCH=NO ARCHS=x86_64 -scheme coreaudio-ios-example -configuration Debug -derivedDataPath build -sdk iphonesimulator
 
+  apple-tier-3-check:
+    runs-on: macOS-14
+    strategy:
+      matrix:
+        target: [
+          aarch64-apple-visionos,
+          aarch64-apple-visionos-sim,
+        ]
+    steps:
+    - uses: actions/checkout@v4
+
+    - uses: dtolnay/rust-toolchain@master
+      with:
+        toolchain: nightly
+        components: rust-src
+
+    - name: Install Xcode Command Line Tools
+      # TODO: Remove this when xcode 15.2 or later is the default in
+      # https://github.com/actions/runner-images/blob/main/images/macos/macos-14-arm64-Readme.md#xcode
+      run: sudo xcode-select --switch /Applications/Xcode_15.4.app/Contents/Developer
+
+    - name: Build for visionOS target ${{matrix.target}}
+      run: cargo +nightly build -Z build-std --target=${{matrix.target}}
+
   # Build the docs with all features to make sure docs.rs will work.
   macos-docs:
     runs-on: macOS-latest

Cargo.toml

@@ -3,7 +3,7 @@ name = "coreaudio-rs"
 version = "0.12.0"
 authors = ["mitchmindtree <mitchell.nordine@gmail.com>", "yupferris <jake@fusetools.com>"]
 description = "A friendly rust interface for Apple's CoreAudio API."
-keywords = ["core", "audio", "unit", "osx", "ios"]
+keywords = ["core", "audio", "unit", "osx", "ios", "visionos"]
 readme = "README.md"
 license = "MIT/Apache-2.0"
 edition = '2018'
@@ -30,3 +30,6 @@ core-foundation-sys = "0.8.3"
 all-features = true
 default-target = "x86_64-apple-darwin"
 targets = ["x86_64-apple-darwin", "x86_64-apple-ios"]
+
+[patch.crates-io]
+coreaudio-sys = { git = "https://github.com/simlay/coreaudio-sys.git", branch = "tier-3-more-apple-targets"}

src/audio_unit/macos_helpers.rs

@@ -1,5 +1,5 @@
 /// This is a collection of helper functions for performing common tasks on macOS.
-/// These functions are only implemented for macOS, not iOS.
+/// These functions are only implemented for macOS, not iOS or visionOS.
 use crate::error::Error;
 use std::collections::VecDeque;
 use std::ffi::CStr;

src/audio_unit/mod.rs

@@ -382,6 +382,7 @@ pub fn set_property<T>(
 /// Gets the value of an **AudioUnit** property.
 ///
 /// **Available** in iOS 2.0 and later.
+/// **Available** in visionOS 1.0 and later.
 ///
 /// Parameters
 /// ----------
@@ -414,12 +415,13 @@ pub fn get_property<T>(
 /// Gets the value of a specified audio session property.
 ///
 /// **Available** in iOS 2.0 and later.
+/// **Available** in visionOS 1.0 and later.
 ///
 /// Parameters
 /// ----------
 ///
 /// - **id**: The identifier of the property.
-#[cfg(target_os = "ios")]
+#[cfg(any(target_os = "ios", target_os = "visionos"))]
 pub fn audio_session_get_property<T>(id: u32) -> Result<T, Error> {
     let mut size = ::std::mem::size_of::<T>() as u32;
     unsafe {

src/audio_unit/render_callback.rs

@@ -559,7 +559,10 @@ impl AudioUnit {
             let buffer_frame_size: u32 = self.get_property(id, Scope::Global, Element::Output)?;
             buffer_frame_size
         };
-        #[cfg(target_os = "ios")]
+
+        // TODO: watchOS and tvOS. It's unclear how to get the frame buffer size on watchOS or
+        // tvOS.
+        #[cfg(any(target_os = "ios", target_os = "visionos"))]
         let mut buffer_frame_size: u32 = {
             let id = sys::kAudioSessionProperty_CurrentHardwareIOBufferDuration;
             let seconds: f32 = super::audio_session_get_property(id)?;