Support pipewire as host

.github/actions/determine-msrv/action.yml

@@ -12,6 +12,10 @@ inputs:
     description: The MSRV for PulseAudio backend (optional, Linux only)
     required: false
     default: ''
+  pipewire-msrv:
+    description: The MSRV for Pipewire backend (optional, Linux only)
+    required: false
+    default: ''
 
 outputs:
   all-features:
@@ -28,11 +32,15 @@ runs:
         PLATFORM_MSRV="${{ inputs.platform-msrv }}"
         JACK_MSRV="${{ inputs.jack-msrv }}"
         PULSEAUDIO_MSRV="${{ inputs.pulseaudio-msrv }}"
+        PIPEWIRE_MSRV="${{ inputs.pipewire-msrv }}"
         # Use sort -V to find the maximum version
         VERSIONS="$PLATFORM_MSRV $JACK_MSRV"
         if [ -n "$PULSEAUDIO_MSRV" ]; then
           VERSIONS="$VERSIONS $PULSEAUDIO_MSRV"
         fi
+        if [ -n "$PIPEWIRE_MSRV" ]; then
+          VERSIONS="$VERSIONS $PIPEWIRE_MSRV"
+        fi
         MAX_MSRV=$(printf '%s\n' $VERSIONS | sort -V | tail -n1)
         echo "all-features=$MAX_MSRV" >> $GITHUB_OUTPUT
-        echo "Platform MSRV: $PLATFORM_MSRV, JACK MSRV: $JACK_MSRV, PulseAudio MSRV: $PULSEAUDIO_MSRV, Using for --all-features: $MAX_MSRV"
+        echo "Platform MSRV: $PLATFORM_MSRV, JACK MSRV: $JACK_MSRV, PulseAudio MSRV: $PULSEAUDIO_MSRV, PIPEWIRE_MSRV: $PIPEWIRE_MSRV, Using for --all-features: $MAX_MSRV"

.github/workflows/platforms.yml

@@ -29,11 +29,12 @@ env:
   MSRV_COREAUDIO: "1.80"
   MSRV_JACK: "1.82"
   MSRV_PULSEAUDIO: "1.88"
+  MSRV_PIPEWIRE: "1.82"
   MSRV_WASIP1: "1.78"
   MSRV_WASM: "1.82"
   MSRV_WINDOWS: "1.82"
 
-  PACKAGES_LINUX: libasound2-dev libjack-jackd2-dev libjack-jackd2-0 libdbus-1-dev
+  PACKAGES_LINUX: libasound2-dev libjack-jackd2-dev libjack-jackd2-0 libdbus-1-dev libpipewire-0.3-dev
 
   ANDROID_COMPILE_SDK: "30"
   ANDROID_BUILD_TOOLS: "30.0.3"
@@ -66,6 +67,7 @@ jobs:
           platform-msrv: ${{ env.MSRV_ALSA }}
           jack-msrv: ${{ env.MSRV_JACK }}
           pulseaudio-msrv: ${{ env.MSRV_PULSEAUDIO }}
+          pipewire-msrv: ${{ env.MSRV_PIPEWIRE }}
 
       - name: Install Rust MSRV (${{ env.MSRV_ALSA }})
         uses: dtolnay/rust-toolchain@master
@@ -153,10 +155,10 @@ jobs:
         run: cross +${{ env.MSRV_ALSA }} test --no-default-features --workspace --verbose --target ${{ env.TARGET }}
 
       - name: Run tests (all features)
-        run: cross +${{ steps.msrv.outputs.all-features }} test --all-features --workspace --verbose --target ${{ env.TARGET }}
+        run: cross +${{ steps.msrv.outputs.all-features }} test --features=jack,pulseaudio --workspace --verbose --target ${{ env.TARGET }}
 
       - name: Check examples (all features)
-        run: cross +${{ steps.msrv.outputs.all-features }} test --all-features --workspace --verbose --target ${{ env.TARGET }}
+        run: cross +${{ steps.msrv.outputs.all-features }} test --features=jack,pulseaudio --workspace --verbose --target ${{ env.TARGET }}
 
   # Windows (x86_64 and i686)
   windows:

.github/workflows/quality.yml

@@ -92,7 +92,7 @@ jobs:
         if: runner.os == 'Linux'
         uses: awalsh128/cache-apt-pkgs-action@latest
         with:
-          packages: libasound2-dev libjack-jackd2-dev libjack-jackd2-0 libdbus-1-dev
+          packages: libasound2-dev libjack-jackd2-dev libjack-jackd2-0 libdbus-1-dev libpipewire-0.3-dev
 
       - name: Setup ASIO SDK
         if: runner.os == 'Windows'
@@ -128,7 +128,7 @@ jobs:
       - name: Cache Linux audio packages
         uses: awalsh128/cache-apt-pkgs-action@latest
         with:
-          packages: libasound2-dev libjack-jackd2-dev libjack-jackd2-0 libdbus-1-dev
+          packages: libasound2-dev libjack-jackd2-dev libjack-jackd2-0 libdbus-1-dev libpipewire-0.3-dev
 
       - name: Install Rust toolchain
         uses: dtolnay/rust-toolchain@nightly

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `DeviceBusy` error variant to `SupportedStreamConfigsError`, `DefaultStreamConfigError`, and
   `BuildStreamError` for retryable device access errors (EBUSY, EAGAIN).
 - **PulseAudio**: New host for Linux and some BSDs using the PulseAudio API.
+- **Pipewire**: New host for Linux and some BSDs using the Pipewire API.
 
 ### Changed
 

Cargo.toml

@@ -32,6 +32,12 @@ pulseaudio = ["dep:pulseaudio", "dep:futures"]
 # Note: JACK must be installed separately on all platforms
 jack = ["dep:jack"]
 
+# PipeWire backend
+# Provides audio I/O on Linux and some BSDs via the PipeWire multimedia server
+# Requires: PipeWire server and client libraries installed on the system
+# Platform: Linux, DragonFly BSD, FreeBSD, NetBSD
+pipewire = ["dep:pipewire"]
+
 # Audio thread priority elevation
 # Raises the audio callback thread to real-time priority for lower latency and fewer glitches
 # Requires: On Linux, either rtkit or appropriate user permissions (e.g. limits.conf or capabilities)
@@ -103,6 +109,7 @@ audio_thread_priority = { version = "0.34", optional = true }
 jack = { version = "0.13", optional = true }
 pulseaudio = { version = "0.3", optional = true }
 futures = { version = "0.3", optional = true }
+pipewire = { version = "0.9", optional = true, features = ["v0_3_53"] }
 
 [target.'cfg(target_vendor = "apple")'.dependencies]
 mach2 = "0.5"

Cross.toml

@@ -2,6 +2,4 @@
 dockerfile = "Dockerfile"
 
 [target.armv7-unknown-linux-gnueabihf.env]
-passthrough = [
-    "RUSTFLAGS",
-]
+passthrough = ["RUSTFLAGS"]

Dockerfile

@@ -7,4 +7,5 @@ ENV PKG_CONFIG_PATH=/usr/lib/arm-linux-gnueabihf/pkgconfig/
 RUN dpkg --add-architecture armhf && \
     apt-get update && \
     apt-get install libasound2-dev:armhf -y && \
-    apt-get install libjack-jackd2-dev:armhf libjack-jackd2-0:armhf -y \
+    apt-get install libjack-jackd2-dev:armhf libjack-jackd2-0:armhf -y
+# TODO: now the cross-rs is based on ubuntu:20.04, so it does not contain pipewire-0.3-dev

README.md

@@ -112,6 +112,17 @@ Enables the PulseAudio backend. PulseAudio is a sound server commonly used on Li
 - 
 **Usage:** See the [beep example](examples/beep.rs) for selecting the PulseAudio host at runtime.
 
+### `pipewire`
+
+**Platform:** Linux, DragonFly BSD, FreeBSD, NetBSD
+
+Enables the Pipewire backend. Pipewire is a media server commonly used on Linux desktops.
+
+**Requirements:**
+- Pipewire server and client libraries must be installed on the system
+- 
+**Usage:** See the [beep example](examples/beep.rs) for selecting the Pipewire host at runtime.
+
 ### `wasm-bindgen`
 
 **Platform:** WebAssembly (wasm32-unknown-unknown)
@@ -198,6 +209,7 @@ If you receive errors about no default input or output device:
 
 - **Linux/ALSA:** Ensure your user is in the `audio` group and that ALSA is properly configured
 - **Linux/PulseAudio:** Check that PulseAudio is running: `pulseaudio --check`
+- **Linux/Pipewire:** Check that Pipewire is running: `systemd --user status pipewire`
 - **Windows:** Verify your audio device is enabled in Sound Settings
 - **macOS:** Check System Preferences > Sound for available devices
 - **Mobile (iOS/Android):** Ensure your app has microphone/audio permissions
@@ -236,6 +248,8 @@ For platform-specific features, enable the relevant features:
 ```bash
 cargo run --example beep --features asio  # Windows ASIO
 cargo run --example beep --features jack  # JACK backend
+cargo run --example beep --features pulseaudio  # PulseAudio backend
+cargo run --example beep --features pipewire  # Pipewire backend
 ```
 
 ## Contributing

examples/beep.rs

@@ -31,6 +31,10 @@ struct Opt {
     /// Use the PulseAudio host. Requires `--features pulseaudio`.
     #[arg(long, default_value_t = false)]
     pulseaudio: bool,
+
+    /// Use the Pipewire host. Requires `--features pipewire`
+    #[arg(long, default_value_t = false)]
+    pipewire: bool,
 }
 
 fn main() -> anyhow::Result<()> {
@@ -42,7 +46,8 @@ fn main() -> anyhow::Result<()> {
     let mut jack_host_id = Err(HostUnavailable);
     #[allow(unused_mut, unused_assignments)]
     let mut pulseaudio_host_id = Err(HostUnavailable);
-
+    #[allow(unused_mut, unused_assignments)]
+    let mut pipewire_host_id = Err(HostUnavailable);
     #[cfg(any(
         target_os = "linux",
         target_os = "dragonfly",
@@ -59,6 +64,10 @@ fn main() -> anyhow::Result<()> {
         {
             pulseaudio_host_id = Ok(cpal::HostId::PulseAudio);
         }
+        #[cfg(feature = "pipewire")]
+        {
+            pipewire_host_id = Ok(cpal::HostId::PipeWire);
+        }
     }
 
     // Manually check for flags. Can be passed through cargo with -- e.g.
@@ -71,6 +80,10 @@ fn main() -> anyhow::Result<()> {
         pulseaudio_host_id
             .and_then(cpal::host_from_id)
             .expect("make sure `--features pulseaudio` is specified, and the platform is supported")
+    } else if opt.pipewire {
+        pipewire_host_id
+            .and_then(cpal::host_from_id)
+            .expect("make sure `--features pipewire` is specified, and the platform is supported")
     } else {
         cpal::default_host()
     };

examples/record_wav.rs

@@ -4,7 +4,7 @@
 
 use clap::Parser;
 use cpal::traits::{DeviceTrait, HostTrait, StreamTrait};
-use cpal::{FromSample, Sample};
+use cpal::{FromSample, HostUnavailable, Sample};
 use std::fs::File;
 use std::io::BufWriter;
 use std::sync::{Arc, Mutex};
@@ -20,58 +20,70 @@ struct Opt {
     #[arg(long, default_value_t = 3)]
     duration: u64,
 
-    /// Use the JACK host
-    #[cfg(all(
-        any(
-            target_os = "linux",
-            target_os = "dragonfly",
-            target_os = "freebsd",
-            target_os = "netbsd"
-        ),
-        feature = "jack"
-    ))]
-    #[arg(short, long)]
-    #[allow(dead_code)]
+    /// Use the JACK host. Requires `--features jack`.
+    #[arg(long, default_value_t = false)]
     jack: bool,
+
+    /// Use the PulseAudio host. Requires `--features pulseaudio`.
+    #[arg(long, default_value_t = false)]
+    pulseaudio: bool,
+
+    /// Use the Pipewire host. Requires `--features pipewire`
+    #[arg(long, default_value_t = false)]
+    pipewire: bool,
 }
 
 fn main() -> Result<(), anyhow::Error> {
     let opt = Opt::parse();
 
-    // Conditionally compile with jack if the feature is specified.
-    #[cfg(all(
-        any(
-            target_os = "linux",
-            target_os = "dragonfly",
-            target_os = "freebsd",
-            target_os = "netbsd"
-        ),
-        feature = "jack"
+    // Jack/PulseAudio support must be enabled at compile time, and is
+    // only available on some platforms.
+    #[allow(unused_mut, unused_assignments)]
+    let mut jack_host_id = Err(HostUnavailable);
+    #[allow(unused_mut, unused_assignments)]
+    let mut pulseaudio_host_id = Err(HostUnavailable);
+    #[allow(unused_mut, unused_assignments)]
+    let mut pipewire_host_id = Err(HostUnavailable);
+    #[cfg(any(
+        target_os = "linux",
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "netbsd"
     ))]
+    {
+        #[cfg(feature = "jack")]
+        {
+            jack_host_id = Ok(cpal::HostId::Jack);
+        }
+
+        #[cfg(feature = "pulseaudio")]
+        {
+            pulseaudio_host_id = Ok(cpal::HostId::PulseAudio);
+        }
+        #[cfg(feature = "pipewire")]
+        {
+            pipewire_host_id = Ok(cpal::HostId::PipeWire);
+        }
+    }
+
     // Manually check for flags. Can be passed through cargo with -- e.g.
-    // cargo run --release --example beep --features jack -- --jack
+    // cargo run --release --example record_wav --features jack -- --jack
     let host = if opt.jack {
-        cpal::host_from_id(cpal::available_hosts()
-            .into_iter()
-            .find(|id| *id == cpal::HostId::Jack)
-            .expect(
-                "make sure --features jack is specified. only works on OSes where jack is available",
-            )).expect("jack host unavailable")
+        jack_host_id
+            .and_then(cpal::host_from_id)
+            .expect("make sure `--features jack` is specified, and the platform is supported")
+    } else if opt.pulseaudio {
+        pulseaudio_host_id
+            .and_then(cpal::host_from_id)
+            .expect("make sure `--features pulseaudio` is specified, and the platform is supported")
+    } else if opt.pipewire {
+        pipewire_host_id
+            .and_then(cpal::host_from_id)
+            .expect("make sure `--features pipewire` is specified, and the platform is supported")
     } else {
         cpal::default_host()
     };
 
-    #[cfg(any(
-        not(any(
-            target_os = "linux",
-            target_os = "dragonfly",
-            target_os = "freebsd",
-            target_os = "netbsd"
-        )),
-        not(feature = "jack")
-    ))]
-    let host = cpal::default_host();
-
     // Set up the input device and stream with the default input config.
     let device = if let Some(device) = opt.device {
         let id = &device.parse().expect("failed to parse input device id");