use core::fmt;
pub struct Demangle<'a> {
inner: &'a str,
elements: usize,
}
pub fn demangle(s: &str) -> Result<Demangle, ()> {
let inner;
if s.len() > 4 && s.starts_with("_ZN") && s.ends_with('E') {
inner = &s[3..s.len() - 1];
} else if s.len() > 3 && s.starts_with("ZN") && s.ends_with('E') {
inner = &s[2..s.len() - 1];
} else if s.len() > 5 && s.starts_with("__ZN") && s.ends_with('E') {
inner = &s[4..s.len() - 1];
} else {
return Err(());
}
if inner.bytes().any(|c| c & 0x80 != 0) {
return Err(());
}
let mut elements = 0;
let mut chars = inner.chars().peekable();
loop {
let mut i = 0usize;
while let Some(&c) = chars.peek() {
if !c.is_digit(10) {
break
}
chars.next();
let next = i.checked_mul(10)
.and_then(|i| i.checked_add(c as usize - '0' as usize));
i = match next {
Some(i) => i,
None => {
return Err(());
}
};
}
if i == 0 {
if !chars.next().is_none() {
return Err(());
}
break;
} else if chars.by_ref().take(i).count() != i {
return Err(());
} else {
elements += 1;
}
}
Ok(Demangle {
inner: inner,
elements: elements,
})
}
fn is_rust_hash(s: &str) -> bool {
s.starts_with('h') && s[1..].chars().all(|c| c.is_digit(16))
}
impl<'a> fmt::Display for Demangle<'a> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut inner = self.inner;
for element in 0..self.elements {
let mut rest = inner;
while rest.chars().next().unwrap().is_digit(10) {
rest = &rest[1..];
}
let i: usize = inner[..(inner.len() - rest.len())].parse().unwrap();
inner = &rest[i..];
rest = &rest[..i];
if f.alternate() && element+1 == self.elements && is_rust_hash(&rest) {
break;
}
if element != 0 {
try!(f.write_str("::"));
}
if rest.starts_with("_$") {
rest = &rest[1..];
}
while !rest.is_empty() {
if rest.starts_with('.') {
if let Some('.') = rest[1..].chars().next() {
try!(f.write_str("::"));
rest = &rest[2..];
} else {
try!(f.write_str("."));
rest = &rest[1..];
}
} else if rest.starts_with('$') {
macro_rules! demangle {
($($pat:expr => $demangled:expr,)*) => ({
$(if rest.starts_with($pat) {
try!(f.write_str($demangled));
rest = &rest[$pat.len()..];
} else)*
{
try!(f.write_str(rest));
break;
}
})
}
demangle! {
"$SP$" => "@",
"$BP$" => "*",
"$RF$" => "&",
"$LT$" => "<",
"$GT$" => ">",
"$LP$" => "(",
"$RP$" => ")",
"$C$" => ",",
"$u7e$" => "~",
"$u20$" => " ",
"$u27$" => "'",
"$u3d$" => "=",
"$u5b$" => "[",
"$u5d$" => "]",
"$u7b$" => "{",
"$u7d$" => "}",
"$u3b$" => ";",
"$u2b$" => "+",
"$u21$" => "!",
"$u22$" => "\"",
}
} else {
let idx = match rest.char_indices().find(|&(_, c)| c == '$' || c == '.') {
None => rest.len(),
Some((i, _)) => i,
};
try!(f.write_str(&rest[..idx]));
rest = &rest[idx..];
}
}
}
Ok(())
}
}
#[cfg(test)]
mod tests {
use std::prelude::v1::*;
macro_rules! t {
($a:expr, $b:expr) => (assert!(ok($a, $b)))
}
macro_rules! t_err {
($a:expr) => (assert!(ok_err($a)))
}
macro_rules! t_nohash {
($a:expr, $b:expr) => ({
assert_eq!(format!("{:#}", ::demangle($a)), $b);
})
}
fn ok(sym: &str, expected: &str) -> bool {
match ::try_demangle(sym) {
Ok(s) => {
if s.to_string() == expected {
true
} else {
println!("\n{}\n!=\n{}\n", s, expected);
false
}
}
Err(_) => {
println!("error demangling");
false
}
}
}
fn ok_err(sym: &str) -> bool {
match ::try_demangle(sym) {
Ok(_) => {
println!("succeeded in demangling");
false
}
Err(_) => ::demangle(sym).to_string() == sym,
}
}
#[test]
fn demangle() {
t_err!("test");
t!("_ZN4testE", "test");
t_err!("_ZN4test");
t!("_ZN4test1a2bcE", "test::a::bc");
}
#[test]
fn demangle_dollars() {
t!("_ZN4$RP$E", ")");
t!("_ZN8$RF$testE", "&test");
t!("_ZN8$BP$test4foobE", "*test::foob");
t!("_ZN9$u20$test4foobE", " test::foob");
t!("_ZN35Bar$LT$$u5b$u32$u3b$$u20$4$u5d$$GT$E", "Bar<[u32; 4]>");
}
#[test]
fn demangle_many_dollars() {
t!("_ZN13test$u20$test4foobE", "test test::foob");
t!("_ZN12test$BP$test4foobE", "test*test::foob");
}
#[test]
fn demangle_osx() {
t!("__ZN5alloc9allocator6Layout9for_value17h02a996811f781011E", "alloc::allocator::Layout::for_value::h02a996811f781011");
t!("__ZN38_$LT$core..option..Option$LT$T$GT$$GT$6unwrap18_MSG_FILE_LINE_COL17haf7cb8d5824ee659E", "<core::option::Option<T>>::unwrap::_MSG_FILE_LINE_COL::haf7cb8d5824ee659");
t!("__ZN4core5slice89_$LT$impl$u20$core..iter..traits..IntoIterator$u20$for$u20$$RF$$u27$a$u20$$u5b$T$u5d$$GT$9into_iter17h450e234d27262170E", "core::slice::<impl core::iter::traits::IntoIterator for &'a [T]>::into_iter::h450e234d27262170");
}
#[test]
fn demangle_windows() {
t!("ZN4testE", "test");
t!("ZN13test$u20$test4foobE", "test test::foob");
t!("ZN12test$RF$test4foobE", "test&test::foob");
}
#[test]
fn demangle_elements_beginning_with_underscore() {
t!("_ZN13_$LT$test$GT$E", "<test>");
t!("_ZN28_$u7b$$u7b$closure$u7d$$u7d$E", "{{closure}}");
t!("_ZN15__STATIC_FMTSTRE", "__STATIC_FMTSTR");
}
#[test]
fn demangle_trait_impls() {
t!("_ZN71_$LT$Test$u20$$u2b$$u20$$u27$static$u20$as$u20$foo..Bar$LT$Test$GT$$GT$3barE",
"<Test + 'static as foo::Bar<Test>>::bar");
}
#[test]
fn demangle_without_hash() {
let s = "_ZN3foo17h05af221e174051e9E";
t!(s, "foo::h05af221e174051e9");
t_nohash!(s, "foo");
}
#[test]
fn demangle_without_hash_edgecases() {
t_nohash!("_ZN3fooE", "foo");
t_nohash!("_ZN3foo3barE", "foo::bar");
t_nohash!("_ZN3foo20h05af221e174051e9abcE", "foo");
t_nohash!("_ZN3foo5h05afE", "foo");
t_nohash!("_ZN17h05af221e174051e93fooE", "h05af221e174051e9::foo");
t_nohash!("_ZN3foo16ffaf221e174051e9E", "foo::ffaf221e174051e9");
t_nohash!("_ZN3foo17hg5af221e174051e9E", "foo::hg5af221e174051e9");
}
#[test]
fn demangle_thinlto() {
t!("_ZN3fooE.llvm.9D1C9369", "foo");
t!("_ZN3fooE.llvm.9D1C9369@@16", "foo");
t_nohash!("_ZN9backtrace3foo17hbb467fcdaea5d79bE.llvm.A5310EB9", "backtrace::foo");
}
#[test]
fn demangle_llvm_ir_branch_labels() {
t!("_ZN4core5slice77_$LT$impl$u20$core..ops..index..IndexMut$LT$I$GT$$u20$for$u20$$u5b$T$u5d$$GT$9index_mut17haf9727c2edfbc47bE.exit.i.i", "core::slice::<impl core::ops::index::IndexMut<I> for [T]>::index_mut::haf9727c2edfbc47b.exit.i.i");
t_nohash!("_ZN4core5slice77_$LT$impl$u20$core..ops..index..IndexMut$LT$I$GT$$u20$for$u20$$u5b$T$u5d$$GT$9index_mut17haf9727c2edfbc47bE.exit.i.i", "core::slice::<impl core::ops::index::IndexMut<I> for [T]>::index_mut.exit.i.i");
}
#[test]
fn demangle_ignores_suffix_that_doesnt_look_like_a_symbol() {
t_err!("_ZN3fooE.llvm moocow");
}
#[test]
fn dont_panic() {
::demangle("_ZN2222222222222222222222EE").to_string();
::demangle("_ZN5*70527e27.ll34csaғE").to_string();
::demangle("_ZN5*70527a54.ll34_$b.1E").to_string();
::demangle("\
_ZN5~saäb4e\n\
2734cOsbE\n\
5usage20h)3\0\0\0\0\0\0\07e2734cOsbE\
").to_string();
}
#[test]
fn invalid_no_chop() {
t_err!("_ZNfooE");
}
#[test]
fn handle_assoc_types() {
t!("_ZN151_$LT$alloc..boxed..Box$LT$alloc..boxed..FnBox$LT$A$C$$u20$Output$u3d$R$GT$$u20$$u2b$$u20$$u27$a$GT$$u20$as$u20$core..ops..function..FnOnce$LT$A$GT$$GT$9call_once17h69e8f44b3723e1caE", "<alloc::boxed::Box<alloc::boxed::FnBox<A, Output=R> + 'a> as core::ops::function::FnOnce<A>>::call_once::h69e8f44b3723e1ca");
}
#[test]
fn handle_bang() {
t!(
"_ZN88_$LT$core..result..Result$LT$$u21$$C$$u20$E$GT$$u20$as$u20$std..process..Termination$GT$6report17hfc41d0da4a40b3e8E",
"<core::result::Result<!, E> as std::process::Termination>::report::hfc41d0da4a40b3e8"
);
}
}