fix: stream config validation for all backends

[roderickvd]

Every backend now calls validate_stream_config, so channels: 0, sample_rate: 0, and BufferSize::Fixed(0) return ErrorKind::InvalidInput instead of reaching the driver and silently doing the wrong thing.

Beyond the validation sweep:

• AAudio: channel counts are no longer hardcoded but go up to 8 (ITU-R BS.2051)
• AudioWorklet/WebAudio: switched from a continuous 8–96 kHz range to discrete rates between 3 and 768 kHz; AudioWorklet also gets support for enumerating proper buffer size ranges and reads now renderQuantumSize back from the AudioContext so buffer_size() reflects what the browser actually chose.
• JACK: channel counts are no longer hardcoded but count live system ports from the server
• PulseAudio: playback max buffer size now correctly accounts for the double-buffer (max_length = 2 * tlength).
• WASAPI: supported_*_configs() now report the device scheduling period instead of Range { min: 0, max: u32::MAX }.

[Copilot]

Pull request overview

This PR centralizes basic StreamConfig input validation across backends (rejecting channels = 0, sample_rate = 0, and BufferSize::Fixed(0) with ErrorKind::InvalidInput) and updates several backends’ reported supported configurations (channels, sample rates, and buffer sizing) to better match real platform behavior.

Changes:

• Add validate_stream_config calls across backends’ build_*_stream_raw entry points to prevent invalid configs from reaching drivers.
• Update WebAudio/AudioWorklet supported config enumeration (channels up to 64; discrete standard rates up to 768 kHz) and update WASAPI/PulseAudio/JACK reporting behavior.
• Extend ASIO bindings to expose buffer size preference/step constraints and validate stepped buffer sizes.

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/lib.rs	Keeps validate_stream_config as the shared guard for invalid StreamConfig values.
src/host/webaudio/mod.rs	Switches to discrete sample-rate enumeration and raises channel/rate ceilings; adds validation call.
src/host/audioworklet/mod.rs	Updates supported configs/rates; reads back actual quantum size; adds validation call.
src/host/wasapi/device.rs	Reports software-stack buffer sizing as Unknown and substitutes device period in frames where possible; adds validation call.
src/host/pulseaudio/mod.rs	Corrects playback max buffer sizing for PulseAudio’s double-buffer; adds validation calls and fixed-size checks.
src/host/pipewire/device.rs	Adds upfront config validation and quantum-range validation for fixed buffer sizes.
src/host/jack/device.rs	Enumerates supported channels based on live system port counts; adds config validation.
src/host/coreaudio/macos/device.rs	Adds upfront validation and pre-validates fixed buffer sizes against the device’s reported range.
src/host/coreaudio/ios/mod.rs	Adds upfront validation and explicit fixed buffer-size range validation (256–4096).
src/host/asio/stream.rs	Adds upfront validation and enforces stepped buffer-size constraints from the driver.
src/host/aaudio/mod.rs	Expands channel enumeration up to 8 and switches reported buffer size to Unknown; adds validation call.
CHANGELOG.md	Documents the validation sweep and backend reporting/behavior changes.
asio-sys/src/bindings/mod.rs	Adds BufferPreference and extends BufferSizeRange to carry preferred/step constraints; fixes some c_char pointer typing.
asio-sys/CHANGELOG.md	Documents the BufferPreference/BufferSizeRange API change.

Comments suppressed due to low confidence (1)

src/host/webaudio/mod.rs:240

• The UnsupportedConfig message here omits the sample rate even though valid_config() can reject configurations due to sample_rate (and/or other constraints). Including the offending sample rate and the supported rate constraints would make failures easier to diagnose.

        if !valid_config(config, sample_format) {
            return Err(Error::with_message(
                ErrorKind::UnsupportedConfig,
                format!(
                    "Sample format {sample_format} or channel count {} is not supported",

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[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 5 comments.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated no new comments.