Never trap for LED operations (#434)

google · Apr 20, 2024 · f75edc9 · f75edc9
1 parent 33fe483
commit f75edc9
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Showing 4 changed files with 20 additions and 7 deletions.
diff --git a/crates/prelude/CHANGELOG.md b/crates/prelude/CHANGELOG.md
@@ -4,6 +4,7 @@
 
 ### Minor
 
+- Change `led::{get,set}()` to never trap and return an error instead
 - Document all public API
 - Remove deprecated `println!` macro
 - Add `Sha384` and `HmacSha384` to the `rust-crypto` feature

diff --git a/crates/prelude/src/led.rs b/crates/prelude/src/led.rs
@@ -32,6 +32,7 @@ pub fn count() -> usize {
 /// Returns the status of a LED.
 ///
 /// The `led` argument is the index of the LED. It must be less than [count()].
+#[track_caller]
 pub fn get(led: usize) -> api::Status {
     let status = convert_bool(unsafe { api::get(api::get::Params { led }) }).unwrap();
     match status {
@@ -44,6 +45,7 @@ pub fn get(led: usize) -> api::Status {
 ///
 /// The `led` argument is the index of the LED. It must be less than [count()]. The `status`
 /// argument is the new status.
+#[track_caller]
 pub fn set(led: usize, status: api::Status) {
     let params = api::set::Params { led, status: status as usize };
     convert_unit(unsafe { api::set(params) }).unwrap();

diff --git a/crates/scheduler/CHANGELOG.md b/crates/scheduler/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## 0.3.1-git
 
+### Minor
+
+- Change `led::{get,set}()` to never trap and return an error instead
+
 ### Patch
 
 - Simplify `#[cfg(all)]` attributes between board and applet features

diff --git a/crates/scheduler/src/call/led.rs b/crates/scheduler/src/call/led.rs
@@ -18,9 +18,9 @@ use wasefire_board_api::led::Api as _;
 use wasefire_board_api::Api as Board;
 #[cfg(feature = "board-api-led")]
 use wasefire_board_api::{self as board, Id, Support};
-
 #[cfg(feature = "board-api-led")]
-use crate::Trap;
+use wasefire_error::{Code, Error};
+
 use crate::{DispatchSchedulerCall, SchedulerCall};
 
 pub fn process<B: Board>(call: Api<DispatchSchedulerCall<B>>) {
@@ -44,8 +44,10 @@ fn count<B: Board>(call: SchedulerCall<B, api::count::Sig>) {
 fn get<B: Board>(call: SchedulerCall<B, api::get::Sig>) {
     let api::get::Params { led } = call.read();
     let result = try {
-        let id = Id::new(*led as usize).ok_or(Trap)?;
-        board::Led::<B>::get(id)
+        match Id::new(*led as usize) {
+            Some(id) => board::Led::<B>::get(id),
+            None => Err(Error::user(Code::InvalidArgument)),
+        }
     };
     call.reply(result);
 }
@@ -54,9 +56,13 @@ fn get<B: Board>(call: SchedulerCall<B, api::get::Sig>) {
 fn set<B: Board>(call: SchedulerCall<B, api::set::Sig>) {
     let api::set::Params { led, status } = call.read();
     let result = try {
-        let id = Id::new(*led as usize).ok_or(Trap)?;
-        let on = matches!(api::Status::try_from(*status)?, api::Status::On);
-        board::Led::<B>::set(id, on)
+        match Id::new(*led as usize) {
+            Some(id) => {
+                let on = matches!(api::Status::try_from(*status)?, api::Status::On);
+                board::Led::<B>::set(id, on)
+            }
+            None => Err(Error::user(Code::InvalidArgument)),
+        }
     };
     call.reply(result);
 }