piecrust-uplink 0.21.0

// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
//
// Copyright (c) DUSK NETWORK. All rights reserved.

use core::fmt::Write;
use core::panic::PanicInfo;

unsafe extern "C" {
    pub fn panic(arg_len: u32);
}

#[panic_handler]
unsafe fn handle_panic(info: &PanicInfo) -> ! {
    // SAFETY: This is a panic handler that calls the host's panic function.
    // The ArgbufWriter writes to a known valid buffer, and the panic function
    // is provided by the host runtime.
    unsafe {
        let mut w = crate::ArgbufWriter::default();

        // If we fail in writing to the argument buffer, we just call `panic`
        // after writing a standard message instead.

        if w.write_fmt(format_args!("{}", info.message())).is_err() {
            w = crate::ArgbufWriter::default();
            let _ = write!(w, "PANIC INFO TOO LONG");
        }

        panic(w.ofs() as u32);
        unreachable!()
    }
}