fluencelabs/wasmer
1
0
Fork 0
mirror of https://github.com/fluencelabs/wasmer synced 2025-06-12 08:31:21 +00:00
Code Issues Projects Releases Wiki Activity

Look up exception tables in trap handler.

Browse Source
This commit is contained in:
losfair
2020-01-09 01:42:50 +08:00
parent 5c15ff9673
commit f44517b9fb
1 changed files with 28 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

29
lib/runtime-core/src/fault.rs
View File

@ -375,15 +375,23 @@ extern "C" fn signal_trap_handler(
_ => {}
}
// Now we have looked up all possible handler tables but failed to find a handler
// for this exception that allows a normal return.
//
// So here we check whether this exception is caused by a suspend signal, return the
// state image if so, or throw the exception out otherwise.
let ctx: &mut vm::Ctx = &mut **CURRENT_CTX.with(|x| x.get());
let es_image = fault
.read_stack(None)
.expect("fault.read_stack() failed. Broken invariants?");
if is_suspend_signal {
// If this is a suspend signal, we parse the runtime state and return the resulting image.
let image = build_instance_image(ctx, es_image);
unwind_result = Box::new(image);
} else {
// Otherwise, this is a real exception and we just throw it to the caller.
if es_image.frames.len() > 0 {
eprintln!(
"\n{}",
@ -391,7 +399,26 @@ extern "C" fn signal_trap_handler(
);
es_image.print_backtrace_if_needed();
}
// Just let the error propagate otherwise
// Look up the exception tables and try to find an exception code.
let exc_code = CURRENT_CODE_VERSIONS.with(|versions| {
let versions = versions.borrow();
for v in versions.iter() {
if let Some(table) = v.runnable_module.get_exception_table() {
let ip = fault.ip.get();
let end = v.base + v.msm.total_size;
if ip >= v.base && ip < end {
if let Some(exc_code) = table.offset_to_code.get(&(ip - v.base)) {
return Some(*exc_code);
}
}
}
}
None
});
if let Some(code) = exc_code {
unwind_result = Box::new(code);
}
}
true