1  // Copyright (c) 2025 ADnet Contributors
 2  // This file is part of the AlphaVM library.
 3  
 4  // Licensed under the Apache License, Version 2.0 (the "License");
 5  // you may not use this file except in compliance with the License.
 6  // You may obtain a copy of the License at:
 7  
 8  // http://www.apache.org/licenses/LICENSE-2.0
 9  
10  // Unless required by applicable law or agreed to in writing, software
11  // distributed under the License is distributed on an "AS IS" BASIS,
12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  // See the License for the specific language governing permissions and
14  // limitations under the License.
15  
16  pub use std::error::Error;
17  
18  /// This macro provides a VM runtime environment which will safely halt
19  /// without producing logs that look like unexpected behavior.
20  /// In debug mode, it prints to stderr using the format: "VM safely halted at {location}: {halt message}".
21  #[macro_export]
22  macro_rules! try_vm_runtime {
23      ($e:expr) => {{
24          use std::panic;
25  
26          // Store the previous hook (if any).
27          let previous_hook = panic::take_hook();
28  
29          // Set a custom hook before calling catch_unwind to
30          // indicate that the panic was expected and handled.
31          panic::set_hook(Box::new(|err| {
32              #[cfg(debug_assertions)]
33              {
34                  // Remove all words up to "panicked".
35                  let trimmed = err
36                      .to_string()
37                      .split_ascii_whitespace()
38                      .skip_while(|&word| word != "panicked")
39                      .collect::<Vec<&str>>()
40                      .join(" ");
41  
42                  // Have the message start with "VM safely halted".
43                  let msg = trimmed.replacen("panicked", "VM safely halted", 1);
44                  eprintln!("{msg}");
45              }
46          }));
47  
48          // Perform the operation that may panic.
49          let result = panic::catch_unwind(panic::AssertUnwindSafe($e));
50  
51          // Restore the standard panic hook.
52          panic::set_hook(previous_hook);
53  
54          // Return the result, allowing regular error-handling.
55          result
56      }};
57  }