Merge pull request #2165 from ljedrz/feat/custom_catch_hook

Use a custom panic hook for caught halting
ProvableHQ · Nov 15, 2023 · 0608677 · 0608677
2 parents f06c915 + 00aaa56
commit 0608677
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Showing 4 changed files with 41 additions and 6 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/synthesizer/process/Cargo.toml b/synthesizer/process/Cargo.toml
@@ -83,6 +83,11 @@ package = "snarkvm-synthesizer-snark"
 path = "../../synthesizer/snark"
 version = "=0.16.9"
 
+[dependencies.utilities]
+package = "snarkvm-utilities"
+path = "../../utilities"
+version = "=0.16.8"
+
 [dependencies.aleo-std]
 version = "0.1.18"
 default-features = false

diff --git a/synthesizer/process/src/finalize.rs b/synthesizer/process/src/finalize.rs
@@ -15,6 +15,7 @@
 use super::*;
 use console::program::{Future, Register};
 use synthesizer_program::{Await, FinalizeRegistersState, Operand};
+use utilities::handle_halting;
 
 impl<N: Network> Process<N> {
     /// Finalizes the deployment and fee.
@@ -224,7 +225,7 @@ fn finalize_transition<N: Network, P: FinalizeStorage<N>>(
             // Finalize the command.
             match &command {
                 Command::BranchEq(branch_eq) => {
-                    let result = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
+                    let result = handle_halting!(panic::AssertUnwindSafe(|| {
                         branch_to(counter, branch_eq, finalize, stack, &registers)
                     }));
                     match result {
@@ -238,7 +239,7 @@ fn finalize_transition<N: Network, P: FinalizeStorage<N>>(
                     }
                 }
                 Command::BranchNeq(branch_neq) => {
-                    let result = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
+                    let result = handle_halting!(panic::AssertUnwindSafe(|| {
                         branch_to(counter, branch_neq, finalize, stack, &registers)
                     }));
                     match result {
@@ -276,7 +277,7 @@ fn finalize_transition<N: Network, P: FinalizeStorage<N>>(
                         None => bail!("Transition ID '{transition_id}' not found in call graph"),
                     };
 
-                    let callee_state = match std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
+                    let callee_state = match handle_halting!(panic::AssertUnwindSafe(|| {
                         // Set up the finalize state for the await.
                         setup_await(state, await_, stack, &registers, child_transition_id)
                     })) {
@@ -306,9 +307,8 @@ fn finalize_transition<N: Network, P: FinalizeStorage<N>>(
                     break;
                 }
                 _ => {
-                    let result = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
-                        command.finalize(stack, store, &mut registers)
-                    }));
+                    let result =
+                        handle_halting!(panic::AssertUnwindSafe(|| { command.finalize(stack, store, &mut registers) }));
                     match result {
                         // If the evaluation succeeds with an operation, add it to the list.
                         Ok(Ok(Some(finalize_operation))) => finalize_operations.push(finalize_operation),

diff --git a/utilities/src/error.rs b/utilities/src/error.rs
@@ -37,3 +37,32 @@ impl Error for crate::String {}
 
 #[cfg(not(feature = "std"))]
 impl Error for crate::io::Error {}
+
+/// This purpose of this macro is to catch the instances of halting
+/// without producing logs looking like unexpected panics. It prints
+/// to stderr using the format: "Halted at <location>: <halt message>".
+#[macro_export]
+macro_rules! handle_halting {
+    ($e:expr) => {{
+        use std::panic;
+
+        // Set a custom hook before calling catch_unwind to
+        // indicate that the panic was expected and handled.
+        panic::set_hook(Box::new(|e| {
+            let msg = e.to_string();
+            let msg = msg.split_ascii_whitespace().skip_while(|&word| word != "panicked").collect::<Vec<&str>>();
+            let mut msg = msg.join(" ");
+            msg = msg.replacen("panicked", "Halted", 1);
+            eprintln!("{msg}");
+        }));
+
+        // Perform the operation that may panic.
+        let result = panic::catch_unwind($e);
+
+        // Restore the standard panic hook.
+        let _ = panic::take_hook();
+
+        // Return the result, allowing regular error-handling.
+        result
+    }};
+}