ic-canister-kit 1.0.15

use std::{borrow::BorrowMut, cell::RefCell};

thread_local! {
    static CALL_ONCE: RefCell<bool> = RefCell::new(false);
}

/// 拦截对象
pub struct CallOnceGuard;

impl Drop for CallOnceGuard {
    fn drop(&mut self) {
        CALL_ONCE.with_borrow_mut(|o| *o.borrow_mut() = false)
    }
}

/// 调用一次
#[inline]
pub fn call_once_guard() -> CallOnceGuard {
    if CALL_ONCE.with(|o| *o.borrow()) {
        #[allow(clippy::panic)] // ? SAFETY
        {
            panic!("Too many request.")
        }
    }

    CALL_ONCE.with_borrow_mut(|o| *o.borrow_mut() = true);

    CallOnceGuard
}