diff --git a/ctru-rs/src/applets/error.rs b/ctru-rs/src/applets/error.rs index ac9a3db..6fa7efc 100644 --- a/ctru-rs/src/applets/error.rs +++ b/ctru-rs/src/applets/error.rs @@ -91,31 +91,50 @@ impl PopUp { /// Sets a custom panic hook that uses the error applet to display panic messages. You can also choose to have /// messages printed over stderr along with the pop-up display. /// -/// # Safety -/// -/// The error applet requires that both the [`Apt`] and [`Gfx`] services are active whenever it launches. -/// By calling this function, you promise that you will keep those services alive until either the program ends or -/// you unregister this hook with [`std::panic::take_hook`](https://doc.rust-lang.org/std/panic/fn.take_hook.html). -pub unsafe fn set_panic_hook(use_stderr: bool) { +/// If the `Gfx` service is not initialized during a panic, the error applet will not be displayed and the panic +/// message will be printed over stderr. +pub fn set_panic_hook(use_stderr: bool) { + use crate::services::gfx::GFX_ACTIVE; + + use std::io::Write; + use std::sync::TryLockError; + std::panic::set_hook(Box::new(move |panic_info| { - let mut popup = PopUp::new(Kind::Top); + let _apt = Apt::new(); let thread = std::thread::current(); let name = thread.name().unwrap_or(""); - let payload = format!("thread '{name}' {panic_info}"); + // If we get a `WouldBlock` error, we know that the `Gfx` service has been initialized. + // Otherwise fallback to printing over stderr. + match GFX_ACTIVE.try_lock() { + Err(TryLockError::WouldBlock) => { + if use_stderr { + print_to_stderr(name, panic_info); + } - popup.set_text(&payload); + let payload = format!("thread '{name}' {panic_info}"); - if use_stderr { - eprintln!("{payload}"); - } + let mut popup = PopUp::new(Kind::Top); - unsafe { - popup.launch_unchecked(); + popup.set_text(&payload); + + unsafe { + popup.launch_unchecked(); + } + } + _ => { + print_to_stderr(name, panic_info); + } } - })) + })); + + fn print_to_stderr(name: &str, panic_info: &std::panic::PanicInfo) { + let mut stderr = std::io::stderr().lock(); + + let _ = writeln!(stderr, "thread '{name}' {panic_info}"); + } } impl std::fmt::Display for Error { diff --git a/ctru-rs/src/services/gfx.rs b/ctru-rs/src/services/gfx.rs index 7a6ec6e..9799665 100644 --- a/ctru-rs/src/services/gfx.rs +++ b/ctru-rs/src/services/gfx.rs @@ -239,7 +239,7 @@ pub struct Gfx { _service_handler: ServiceReference, } -static GFX_ACTIVE: Mutex<()> = Mutex::new(()); +pub(crate) static GFX_ACTIVE: Mutex<()> = Mutex::new(()); impl Gfx { /// Initialize a new default service handle.