process.rs

//! Process management syscalls
use crate::{
    task::{exit_current_and_run_next, suspend_current_and_run_next, find_syscall_times},
    timer::get_time_us,
};

#[repr(C)]
#[derive(Debug)]
pub struct TimeVal {
    pub sec: usize,
    pub usec: usize,
}

/// task exits and submit an exit code
pub fn sys_exit(exit_code: i32) -> ! {
    trace!("[kernel] Application exited with code {}", exit_code);
    exit_current_and_run_next();
    panic!("Unreachable in sys_exit!");
}

/// current task gives up resources for other tasks
pub fn sys_yield() -> isize {
    trace!("kernel: sys_yield");
    suspend_current_and_run_next();
    0
}

/// get time with second and microsecond
pub fn sys_get_time(ts: *mut TimeVal, _tz: usize) -> isize {
    trace!("kernel: sys_get_time");
    let us = get_time_us();
    unsafe {
        *ts = TimeVal {
            sec: us / 1_000_000,
            usec: us % 1_000_000,
        };
    }
    0
}

/// get the information of syscall and do some change
pub fn sys_trace(_trace_request: usize, _id: usize, _data: usize) -> isize {
    trace!("kernel: sys_trace");
    match _trace_request {
        0 => {
            let ptr = _id as *const u8;
            unsafe {
                *ptr as isize
            }
        },
        1 => {
            let ptr = _id as *mut u8;
            unsafe {
                *ptr = (_data & 0xFF) as u8;
            }
            0
        },
        2 => {
            find_syscall_times(_id) as isize
        },
        _ => {
            -1
        }
    }
}