Added signal handler to handle WebAssembly traps properly

Please read more about this here: bytecodealliance/wasmtime#15
Code inspired by: pepyakin/wasmtime@625a2b6

Author: syrusakbary

Cargo.lock

@@ -42,6 +42,7 @@ spin = "0.4.10"
 log = "0.4.5"
 target-lexicon = { version = "0.0.3", default-features = false }
 libc = "0.2"
+nix = "0.11"
 
 [build-dependencies]
 wabt = "0.6.0"

Cargo.toml

@@ -4,7 +4,12 @@
 #[macro_export]
 macro_rules! get_instance_function {
     ($instance:expr, $func_index:expr) => {{
+        use crate::sighandler::install_sighandler;
         use std::mem;
+
+        unsafe {
+            install_sighandler();
+        };
         let func_addr = $instance.get_function_pointer($func_index);
         unsafe { mem::transmute(func_addr) }
     }};

src/macros.rs

@@ -12,6 +12,7 @@ extern crate cranelift_wasm;
 extern crate wabt;
 #[macro_use]
 extern crate target_lexicon;
+extern crate nix;
 extern crate spin;
 
 // use std::alloc::System;
@@ -37,6 +38,7 @@ use wabt::wat2wasm;
 mod macros;
 pub mod common;
 pub mod integrations;
+pub mod sighandler;
 #[cfg(test)]
 mod spectests;
 pub mod webassembly;

src/main.rs

@@ -0,0 +1,39 @@
+//! We install signal handlers to handle WebAssembly traps within
+//! our Rust code. Otherwise we will have errors that stop the Rust process
+//! such as `process didn't exit successfully: ... (signal: 8, SIGFPE: erroneous arithmetic operation)`
+//!
+//! Please read more about this here: https://github.com/CraneStation/wasmtime/issues/15
+//! This code is inspired by: https://github.com/pepyakin/wasmtime/commit/625a2b6c0815b21996e111da51b9664feb174622
+use nix::sys::signal::{
+    sigaction, SaFlags, SigAction, SigHandler, SigSet, SIGBUS, SIGFPE, SIGILL, SIGSEGV,
+};
+
+pub unsafe fn install_sighandler() {
+    let sa = SigAction::new(
+        SigHandler::Handler(signal_trap_handler),
+        SaFlags::empty(),
+        SigSet::empty(),
+    );
+    sigaction(SIGFPE, &sa).unwrap();
+    sigaction(SIGILL, &sa).unwrap();
+    sigaction(SIGSEGV, &sa).unwrap();
+    sigaction(SIGBUS, &sa).unwrap();
+    let result = setjmp((&mut setjmp_buffer[..]).as_mut_ptr() as *mut ::nix::libc::c_void);
+    if result != 0 {
+        panic!("Signal Error: {}", result);
+    }
+}
+
+static mut setjmp_buffer: [::nix::libc::c_int; 27] = [0; 27];
+extern "C" {
+    fn setjmp(env: *mut ::nix::libc::c_void) -> ::nix::libc::c_int;
+    fn longjmp(env: *mut ::nix::libc::c_void, val: ::nix::libc::c_int);
+}
+extern "C" fn signal_trap_handler(_: ::nix::libc::c_int) {
+    unsafe {
+        longjmp(
+            (&mut setjmp_buffer).as_mut_ptr() as *mut ::nix::libc::c_void,
+            3,
+        );
+    }
+}