//! [ArceOS](https://github.com/arceos-org/arceos) task management module.
//!
//! This module provides primitives for task management, including task
//! creation, scheduling, sleeping, termination, etc. The scheduler algorithm
//! is configurable by cargo features.
//!
//! # Cargo Features
//!
//! - `multitask`: Enable multi-task support. If it's enabled, complex task
//!   management and scheduling is used, as well as more task-related APIs.
//!   Otherwise, only a few APIs with naive implementation is available.
//! - `irq`: Interrupts are enabled. If this feature is enabled, timer-based
//!   APIs can be used, such as [`sleep`], [`sleep_until`], and
//!   [`WaitQueue::wait_timeout`].
//! - `preempt`: Enable preemptive scheduling.
//! - FIFO cooperative scheduler is the default when no scheduler feature is
//!   selected.
//! - `sched-rr`: Use the [Round-robin preemptive scheduler][2]. It also enables
//!   the `multitask` and `preempt` features if it is enabled.
//! - `sched-cfs`: Use the [Completely Fair Scheduler][3]. It also enables the
//!   the `multitask` and `preempt` features if it is enabled.
//! - `host-test`: Use host-safe fallbacks for unit tests.
//!
//! [1]: ax_sched::FifoScheduler
//! [2]: ax_sched::RRScheduler
//! [3]: ax_sched::CFScheduler

#![cfg_attr(any(not(test), target_os = "none"), no_std)]
#![cfg_attr(all(test, target_os = "none"), no_main)]
#![cfg_attr(all(test, target_os = "none"), feature(custom_test_frameworks))]
#![cfg_attr(doc, feature(doc_cfg))]
#![cfg_attr(
    all(test, target_os = "none"),
    test_runner(crate::bare_metal_test_runner)
)]

#[cfg(all(test, not(target_os = "none"), feature = "multitask"))]
mod tests;

#[cfg(all(test, target_os = "none"))]
fn bare_metal_test_runner(_tests: &[&dyn Fn()]) {}

#[cfg(all(test, target_os = "none"))]
#[unsafe(no_mangle)]
extern "C" fn _start() -> ! {
    loop {
        core::hint::spin_loop();
    }
}

#[cfg(all(test, target_os = "none"))]
#[panic_handler]
fn panic(_info: &core::panic::PanicInfo<'_>) -> ! {
    loop {
        core::hint::spin_loop();
    }
}

#[cfg(feature = "multitask")]
mod build_info {
    include!(concat!(env!("OUT_DIR"), "/build_info.rs"));
}

cfg_if::cfg_if! {
    if #[cfg(feature = "multitask")] {
        #[macro_use]
        extern crate log;
        extern crate alloc;

        #[macro_use]
        mod run_queue;
        mod task;
        mod api;
        #[cfg(feature = "lockdep")]
        mod lockdep;
        #[cfg(feature = "tracepoint-hooks")]
        mod sched_tracepoint;
        #[cfg(feature = "irq")]
        mod irq_notify;
        mod wait_queue;

        #[cfg(feature = "irq")]
        mod timers;

        #[cfg(feature = "multitask")]
        pub mod future;

        #[cfg_attr(doc, doc(cfg(feature = "multitask")))]
        pub use self::api::*;
        #[cfg(feature = "irq")]
        pub use self::irq_notify::IrqNotify;
        pub use self::api::{sleep, sleep_until, yield_now};
        #[cfg(feature = "tracepoint-hooks")]
        pub use self::sched_tracepoint::SchedTracepoint;
    } else {
        mod api_s;
        pub use self::api_s::{sleep, sleep_until, yield_now};
    }
}
