koan-core 0.60.12

Core library for koan — bit-perfect music player. Audio engine, player, database, format strings.
Documentation 
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pub mod analyzer;
pub mod backend;
pub mod buffer;
#[cfg(target_os = "macos")]
pub mod coreaudio_backend;
#[cfg(target_os = "linux")]
pub mod cpal_backend;
#[cfg(target_os = "macos")]
pub mod device;
pub mod dsp;
// AUHAL on macOS, RemoteIO on iOS and tvOS — one engine, two output components.
#[cfg(any(target_os = "macos", target_os = "ios", target_os = "tvos"))]
pub mod engine;
pub mod fade;
// Built on macOS for its tests: the rate it reports is the session's, and that
// logic needs no phone.
#[cfg(any(target_os = "ios", target_os = "tvos", all(test, target_os = "macos")))]
#[cfg_attr(not(any(target_os = "ios", target_os = "tvos")), allow(dead_code))]
pub mod ios_backend;
pub mod opus;
pub mod replaygain;
pub mod streaming;
#[cfg(target_os = "tvos")]
mod toolbox;
pub mod viz;

use backend::{AudioBackend, BackendError, DeviceInfo};

/// Construct the platform-appropriate audio backend.
pub fn platform_backend() -> Box<dyn AudioBackend> {
    #[cfg(target_os = "macos")]
    {
        Box::new(coreaudio_backend::CoreAudioBackend)
    }
    #[cfg(target_os = "linux")]
    {
        Box::new(cpal_backend::CpalBackend::new())
    }
    #[cfg(any(target_os = "ios", target_os = "tvos"))]
    {
        Box::new(ios_backend::IosAudioBackend)
    }
}

/// Whether output holds the platform's audio session: on iOS and tvOS, since
/// the engine last started and until the player releases it. Never elsewhere,
/// where there is no session to hold.
pub(crate) fn session_held() -> bool {
    #[cfg(any(target_os = "ios", target_os = "tvos"))]
    {
        ios_backend::session_held()
    }
    #[cfg(not(any(target_os = "ios", target_os = "tvos")))]
    {
        false
    }
}

pub(crate) fn release_session() {
    #[cfg(any(target_os = "ios", target_os = "tvos"))]
    ios_backend::release_session();
}

/// The platform's audio route changed: on iOS and tvOS, ask the new one for
/// the output's rate and report what it runs at.
pub(crate) fn follow_route() {
    #[cfg(any(target_os = "ios", target_os = "tvos"))]
    ios_backend::follow_route();
}

/// Cross-platform facade: list output devices via the platform backend.
pub fn list_output_devices() -> Result<Vec<DeviceInfo>, BackendError> {
    platform_backend().list_devices()
}

/// Cross-platform facade: get the default output device.
pub fn default_output_device() -> Result<DeviceInfo, BackendError> {
    platform_backend().default_device()
}