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-rw-r--r--vendor/rustc-demangle/src/v0.rs1530
1 files changed, 0 insertions, 1530 deletions
diff --git a/vendor/rustc-demangle/src/v0.rs b/vendor/rustc-demangle/src/v0.rs
deleted file mode 100644
index 3e88fa6..0000000
--- a/vendor/rustc-demangle/src/v0.rs
+++ /dev/null
@@ -1,1530 +0,0 @@
-use core::convert::TryFrom;
-use core::{char, fmt, iter, mem, str};
-
-#[allow(unused_macros)]
-macro_rules! write {
- ($($ignored:tt)*) => {
- compile_error!(
- "use `self.print(value)` or `fmt::Trait::fmt(&value, self.out)`, \
- instead of `write!(self.out, \"{...}\", value)`"
- )
- };
-}
-
-// Maximum recursion depth when parsing symbols before we just bail out saying
-// "this symbol is invalid"
-const MAX_DEPTH: u32 = 500;
-
-/// Representation of a demangled symbol name.
-pub struct Demangle<'a> {
- inner: &'a str,
-}
-
-#[derive(PartialEq, Eq, Debug)]
-pub enum ParseError {
- /// Symbol doesn't match the expected `v0` grammar.
- Invalid,
-
- /// Parsing the symbol crossed the recursion limit (see `MAX_DEPTH`).
- RecursedTooDeep,
-}
-
-/// De-mangles a Rust symbol into a more readable version
-///
-/// This function will take a **mangled** symbol and return a value. When printed,
-/// the de-mangled version will be written. If the symbol does not look like
-/// a mangled symbol, the original value will be written instead.
-pub fn demangle(s: &str) -> Result<(Demangle, &str), ParseError> {
- // First validate the symbol. If it doesn't look like anything we're
- // expecting, we just print it literally. Note that we must handle non-Rust
- // symbols because we could have any function in the backtrace.
- let inner;
- if s.len() > 2 && s.starts_with("_R") {
- inner = &s[2..];
- } else if s.len() > 1 && s.starts_with('R') {
- // On Windows, dbghelp strips leading underscores, so we accept "R..."
- // form too.
- inner = &s[1..];
- } else if s.len() > 3 && s.starts_with("__R") {
- // On OSX, symbols are prefixed with an extra _
- inner = &s[3..];
- } else {
- return Err(ParseError::Invalid);
- }
-
- // Paths always start with uppercase characters.
- match inner.as_bytes()[0] {
- b'A'..=b'Z' => {}
- _ => return Err(ParseError::Invalid),
- }
-
- // only work with ascii text
- if inner.bytes().any(|c| c & 0x80 != 0) {
- return Err(ParseError::Invalid);
- }
-
- // Verify that the symbol is indeed a valid path.
- let try_parse_path = |parser| {
- let mut dummy_printer = Printer {
- parser: Ok(parser),
- out: None,
- bound_lifetime_depth: 0,
- };
- dummy_printer
- .print_path(false)
- .expect("`fmt::Error`s should be impossible without a `fmt::Formatter`");
- dummy_printer.parser
- };
- let mut parser = Parser {
- sym: inner,
- next: 0,
- depth: 0,
- };
- parser = try_parse_path(parser)?;
-
- // Instantiating crate (paths always start with uppercase characters).
- if let Some(&(b'A'..=b'Z')) = parser.sym.as_bytes().get(parser.next) {
- parser = try_parse_path(parser)?;
- }
-
- Ok((Demangle { inner }, &parser.sym[parser.next..]))
-}
-
-impl<'s> fmt::Display for Demangle<'s> {
- fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- let mut printer = Printer {
- parser: Ok(Parser {
- sym: self.inner,
- next: 0,
- depth: 0,
- }),
- out: Some(f),
- bound_lifetime_depth: 0,
- };
- printer.print_path(true)
- }
-}
-
-struct Ident<'s> {
- /// ASCII part of the identifier.
- ascii: &'s str,
- /// Punycode insertion codes for Unicode codepoints, if any.
- punycode: &'s str,
-}
-
-const SMALL_PUNYCODE_LEN: usize = 128;
-
-impl<'s> Ident<'s> {
- /// Attempt to decode punycode on the stack (allocation-free),
- /// and pass the char slice to the closure, if successful.
- /// This supports up to `SMALL_PUNYCODE_LEN` characters.
- fn try_small_punycode_decode<F: FnOnce(&[char]) -> R, R>(&self, f: F) -> Option<R> {
- let mut out = ['\0'; SMALL_PUNYCODE_LEN];
- let mut out_len = 0;
- let r = self.punycode_decode(|i, c| {
- // Check there's space left for another character.
- out.get(out_len).ok_or(())?;
-
- // Move the characters after the insert position.
- let mut j = out_len;
- out_len += 1;
-
- while j > i {
- out[j] = out[j - 1];
- j -= 1;
- }
-
- // Insert the new character.
- out[i] = c;
-
- Ok(())
- });
- if r.is_ok() {
- Some(f(&out[..out_len]))
- } else {
- None
- }
- }
-
- /// Decode punycode as insertion positions and characters
- /// and pass them to the closure, which can return `Err(())`
- /// to stop the decoding process.
- fn punycode_decode<F: FnMut(usize, char) -> Result<(), ()>>(
- &self,
- mut insert: F,
- ) -> Result<(), ()> {
- let mut punycode_bytes = self.punycode.bytes().peekable();
- if punycode_bytes.peek().is_none() {
- return Err(());
- }
-
- let mut len = 0;
-
- // Populate initial output from ASCII fragment.
- for c in self.ascii.chars() {
- insert(len, c)?;
- len += 1;
- }
-
- // Punycode parameters and initial state.
- let base = 36;
- let t_min = 1;
- let t_max = 26;
- let skew = 38;
- let mut damp = 700;
- let mut bias = 72;
- let mut i: usize = 0;
- let mut n: usize = 0x80;
-
- loop {
- // Read one delta value.
- let mut delta: usize = 0;
- let mut w = 1;
- let mut k: usize = 0;
- loop {
- use core::cmp::{max, min};
-
- k += base;
- let t = min(max(k.saturating_sub(bias), t_min), t_max);
-
- let d = match punycode_bytes.next() {
- Some(d @ b'a'..=b'z') => d - b'a',
- Some(d @ b'0'..=b'9') => 26 + (d - b'0'),
- _ => return Err(()),
- };
- let d = d as usize;
- delta = delta.checked_add(d.checked_mul(w).ok_or(())?).ok_or(())?;
- if d < t {
- break;
- }
- w = w.checked_mul(base - t).ok_or(())?;
- }
-
- // Compute the new insert position and character.
- len += 1;
- i = i.checked_add(delta).ok_or(())?;
- n = n.checked_add(i / len).ok_or(())?;
- i %= len;
-
- let n_u32 = n as u32;
- let c = if n_u32 as usize == n {
- char::from_u32(n_u32).ok_or(())?
- } else {
- return Err(());
- };
-
- // Insert the new character and increment the insert position.
- insert(i, c)?;
- i += 1;
-
- // If there are no more deltas, decoding is complete.
- if punycode_bytes.peek().is_none() {
- return Ok(());
- }
-
- // Perform bias adaptation.
- delta /= damp;
- damp = 2;
-
- delta += delta / len;
- let mut k = 0;
- while delta > ((base - t_min) * t_max) / 2 {
- delta /= base - t_min;
- k += base;
- }
- bias = k + ((base - t_min + 1) * delta) / (delta + skew);
- }
- }
-}
-
-impl<'s> fmt::Display for Ident<'s> {
- fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- self.try_small_punycode_decode(|chars| {
- for &c in chars {
- c.fmt(f)?;
- }
- Ok(())
- })
- .unwrap_or_else(|| {
- if !self.punycode.is_empty() {
- f.write_str("punycode{")?;
-
- // Reconstruct a standard Punycode encoding,
- // by using `-` as the separator.
- if !self.ascii.is_empty() {
- f.write_str(self.ascii)?;
- f.write_str("-")?;
- }
- f.write_str(self.punycode)?;
-
- f.write_str("}")
- } else {
- f.write_str(self.ascii)
- }
- })
- }
-}
-
-/// Sequence of lowercase hexadecimal nibbles (`0-9a-f`), used by leaf consts.
-struct HexNibbles<'s> {
- nibbles: &'s str,
-}
-
-impl<'s> HexNibbles<'s> {
- /// Decode an integer value (with the "most significant nibble" first),
- /// returning `None` if it can't fit in an `u64`.
- // FIXME(eddyb) should this "just" use `u128` instead?
- fn try_parse_uint(&self) -> Option<u64> {
- let nibbles = self.nibbles.trim_start_matches("0");
-
- if nibbles.len() > 16 {
- return None;
- }
-
- let mut v = 0;
- for nibble in nibbles.chars() {
- v = (v << 4) | (nibble.to_digit(16).unwrap() as u64);
- }
- Some(v)
- }
-
- /// Decode a UTF-8 byte sequence (with each byte using a pair of nibbles)
- /// into individual `char`s, returning `None` for invalid UTF-8.
- fn try_parse_str_chars(&self) -> Option<impl Iterator<Item = char> + 's> {
- if self.nibbles.len() % 2 != 0 {
- return None;
- }
-
- // FIXME(eddyb) use `array_chunks` instead, when that becomes stable.
- let mut bytes = self
- .nibbles
- .as_bytes()
- .chunks_exact(2)
- .map(|slice| match slice {
- [a, b] => [a, b],
- _ => unreachable!(),
- })
- .map(|[&hi, &lo]| {
- let half = |nibble: u8| (nibble as char).to_digit(16).unwrap() as u8;
- (half(hi) << 4) | half(lo)
- });
-
- let chars = iter::from_fn(move || {
- // As long as there are any bytes left, there's at least one more
- // UTF-8-encoded `char` to decode (or the possibility of error).
- bytes.next().map(|first_byte| -> Result<char, ()> {
- // FIXME(eddyb) this `enum` and `fn` should be somewhere in `core`.
- enum Utf8FirstByteError {
- ContinuationByte,
- TooLong,
- }
- fn utf8_len_from_first_byte(byte: u8) -> Result<usize, Utf8FirstByteError> {
- match byte {
- 0x00..=0x7f => Ok(1),
- 0x80..=0xbf => Err(Utf8FirstByteError::ContinuationByte),
- 0xc0..=0xdf => Ok(2),
- 0xe0..=0xef => Ok(3),
- 0xf0..=0xf7 => Ok(4),
- 0xf8..=0xff => Err(Utf8FirstByteError::TooLong),
- }
- }
-
- // Collect the appropriate amount of bytes (up to 4), according
- // to the UTF-8 length implied by the first byte.
- let utf8_len = utf8_len_from_first_byte(first_byte).map_err(|_| ())?;
- let utf8 = &mut [first_byte, 0, 0, 0][..utf8_len];
- for i in 1..utf8_len {
- utf8[i] = bytes.next().ok_or(())?;
- }
-
- // Fully validate the UTF-8 sequence.
- let s = str::from_utf8(utf8).map_err(|_| ())?;
-
- // Since we included exactly one UTF-8 sequence, and validation
- // succeeded, `str::chars` should return exactly one `char`.
- let mut chars = s.chars();
- match (chars.next(), chars.next()) {
- (Some(c), None) => Ok(c),
- _ => unreachable!(
- "str::from_utf8({:?}) = {:?} was expected to have 1 char, \
- but {} chars were found",
- utf8,
- s,
- s.chars().count()
- ),
- }
- })
- });
-
- // HACK(eddyb) doing a separate validation iteration like this might be
- // wasteful, but it's easier to avoid starting to print a string literal
- // in the first place, than to abort it mid-string.
- if chars.clone().any(|r| r.is_err()) {
- None
- } else {
- Some(chars.map(Result::unwrap))
- }
- }
-}
-
-fn basic_type(tag: u8) -> Option<&'static str> {
- Some(match tag {
- b'b' => "bool",
- b'c' => "char",
- b'e' => "str",
- b'u' => "()",
- b'a' => "i8",
- b's' => "i16",
- b'l' => "i32",
- b'x' => "i64",
- b'n' => "i128",
- b'i' => "isize",
- b'h' => "u8",
- b't' => "u16",
- b'm' => "u32",
- b'y' => "u64",
- b'o' => "u128",
- b'j' => "usize",
- b'f' => "f32",
- b'd' => "f64",
- b'z' => "!",
- b'p' => "_",
- b'v' => "...",
-
- _ => return None,
- })
-}
-
-struct Parser<'s> {
- sym: &'s str,
- next: usize,
- depth: u32,
-}
-
-impl<'s> Parser<'s> {
- fn push_depth(&mut self) -> Result<(), ParseError> {
- self.depth += 1;
- if self.depth > MAX_DEPTH {
- Err(ParseError::RecursedTooDeep)
- } else {
- Ok(())
- }
- }
-
- fn pop_depth(&mut self) {
- self.depth -= 1;
- }
-
- fn peek(&self) -> Option<u8> {
- self.sym.as_bytes().get(self.next).cloned()
- }
-
- fn eat(&mut self, b: u8) -> bool {
- if self.peek() == Some(b) {
- self.next += 1;
- true
- } else {
- false
- }
- }
-
- fn next(&mut self) -> Result<u8, ParseError> {
- let b = self.peek().ok_or(ParseError::Invalid)?;
- self.next += 1;
- Ok(b)
- }
-
- fn hex_nibbles(&mut self) -> Result<HexNibbles<'s>, ParseError> {
- let start = self.next;
- loop {
- match self.next()? {
- b'0'..=b'9' | b'a'..=b'f' => {}
- b'_' => break,
- _ => return Err(ParseError::Invalid),
- }
- }
- Ok(HexNibbles {
- nibbles: &self.sym[start..self.next - 1],
- })
- }
-
- fn digit_10(&mut self) -> Result<u8, ParseError> {
- let d = match self.peek() {
- Some(d @ b'0'..=b'9') => d - b'0',
- _ => return Err(ParseError::Invalid),
- };
- self.next += 1;
- Ok(d)
- }
-
- fn digit_62(&mut self) -> Result<u8, ParseError> {
- let d = match self.peek() {
- Some(d @ b'0'..=b'9') => d - b'0',
- Some(d @ b'a'..=b'z') => 10 + (d - b'a'),
- Some(d @ b'A'..=b'Z') => 10 + 26 + (d - b'A'),
- _ => return Err(ParseError::Invalid),
- };
- self.next += 1;
- Ok(d)
- }
-
- fn integer_62(&mut self) -> Result<u64, ParseError> {
- if self.eat(b'_') {
- return Ok(0);
- }
-
- let mut x: u64 = 0;
- while !self.eat(b'_') {
- let d = self.digit_62()? as u64;
- x = x.checked_mul(62).ok_or(ParseError::Invalid)?;
- x = x.checked_add(d).ok_or(ParseError::Invalid)?;
- }
- x.checked_add(1).ok_or(ParseError::Invalid)
- }
-
- fn opt_integer_62(&mut self, tag: u8) -> Result<u64, ParseError> {
- if !self.eat(tag) {
- return Ok(0);
- }
- self.integer_62()?.checked_add(1).ok_or(ParseError::Invalid)
- }
-
- fn disambiguator(&mut self) -> Result<u64, ParseError> {
- self.opt_integer_62(b's')
- }
-
- fn namespace(&mut self) -> Result<Option<char>, ParseError> {
- match self.next()? {
- // Special namespaces, like closures and shims.
- ns @ b'A'..=b'Z' => Ok(Some(ns as char)),
-
- // Implementation-specific/unspecified namespaces.
- b'a'..=b'z' => Ok(None),
-
- _ => Err(ParseError::Invalid),
- }
- }
-
- fn backref(&mut self) -> Result<Parser<'s>, ParseError> {
- let s_start = self.next - 1;
- let i = self.integer_62()?;
- if i >= s_start as u64 {
- return Err(ParseError::Invalid);
- }
- let mut new_parser = Parser {
- sym: self.sym,
- next: i as usize,
- depth: self.depth,
- };
- new_parser.push_depth()?;
- Ok(new_parser)
- }
-
- fn ident(&mut self) -> Result<Ident<'s>, ParseError> {
- let is_punycode = self.eat(b'u');
- let mut len = self.digit_10()? as usize;
- if len != 0 {
- while let Ok(d) = self.digit_10() {
- len = len.checked_mul(10).ok_or(ParseError::Invalid)?;
- len = len.checked_add(d as usize).ok_or(ParseError::Invalid)?;
- }
- }
-
- // Skip past the optional `_` separator.
- self.eat(b'_');
-
- let start = self.next;
- self.next = self.next.checked_add(len).ok_or(ParseError::Invalid)?;
- if self.next > self.sym.len() {
- return Err(ParseError::Invalid);
- }
-
- let ident = &self.sym[start..self.next];
-
- if is_punycode {
- let ident = match ident.bytes().rposition(|b| b == b'_') {
- Some(i) => Ident {
- ascii: &ident[..i],
- punycode: &ident[i + 1..],
- },
- None => Ident {
- ascii: "",
- punycode: ident,
- },
- };
- if ident.punycode.is_empty() {
- return Err(ParseError::Invalid);
- }
- Ok(ident)
- } else {
- Ok(Ident {
- ascii: ident,
- punycode: "",
- })
- }
- }
-}
-
-struct Printer<'a, 'b: 'a, 's> {
- /// The input parser to demangle from, or `Err` if any (parse) error was
- /// encountered (in order to disallow further likely-incorrect demangling).
- ///
- /// See also the documentation on the `invalid!` and `parse!` macros below.
- parser: Result<Parser<'s>, ParseError>,
-
- /// The output formatter to demangle to, or `None` while skipping printing.
- out: Option<&'a mut fmt::Formatter<'b>>,
-
- /// Cumulative number of lifetimes bound by `for<...>` binders ('G'),
- /// anywhere "around" the current entity (e.g. type) being demangled.
- /// This value is not tracked while skipping printing, as it'd be unused.
- ///
- /// See also the documentation on the `Printer::in_binder` method.
- bound_lifetime_depth: u32,
-}
-
-impl ParseError {
- /// Snippet to print when the error is initially encountered.
- fn message(&self) -> &str {
- match self {
- ParseError::Invalid => "{invalid syntax}",
- ParseError::RecursedTooDeep => "{recursion limit reached}",
- }
- }
-}
-
-/// Mark the parser as errored (with `ParseError::Invalid`), print the
-/// appropriate message (see `ParseError::message`) and return early.
-macro_rules! invalid {
- ($printer:ident) => {{
- let err = ParseError::Invalid;
- $printer.print(err.message())?;
- $printer.parser = Err(err);
- return Ok(());
- }};
-}
-
-/// Call a parser method (if the parser hasn't errored yet),
-/// and mark the parser as errored if it returns `Err`.
-///
-/// If the parser errored, before or now, this returns early,
-/// from the current function, after printing either:
-/// * for a new error, the appropriate message (see `ParseError::message`)
-/// * for an earlier error, only `?` - this allows callers to keep printing
-/// the approximate syntax of the path/type/const, despite having errors,
-/// e.g. `Vec<[(A, ?); ?]>` instead of `Vec<[(A, ?`
-macro_rules! parse {
- ($printer:ident, $method:ident $(($($arg:expr),*))*) => {
- match $printer.parser {
- Ok(ref mut parser) => match parser.$method($($($arg),*)*) {
- Ok(x) => x,
- Err(err) => {
- $printer.print(err.message())?;
- $printer.parser = Err(err);
- return Ok(());
- }
- }
- Err(_) => return $printer.print("?"),
- }
- };
-}
-
-impl<'a, 'b, 's> Printer<'a, 'b, 's> {
- /// Eat the given character from the parser,
- /// returning `false` if the parser errored.
- fn eat(&mut self, b: u8) -> bool {
- self.parser.as_mut().map(|p| p.eat(b)) == Ok(true)
- }
-
- /// Skip printing (i.e. `self.out` will be `None`) for the duration of the
- /// given closure. This should not change parsing behavior, only disable the
- /// output, but there may be optimizations (such as not traversing backrefs).
- fn skipping_printing<F>(&mut self, f: F)
- where
- F: FnOnce(&mut Self) -> fmt::Result,
- {
- let orig_out = self.out.take();
- f(self).expect("`fmt::Error`s should be impossible without a `fmt::Formatter`");
- self.out = orig_out;
- }
-
- /// Print the target of a backref, using the given closure.
- /// When printing is being skipped, the backref will only be parsed,
- /// ignoring the backref's target completely.
- fn print_backref<F>(&mut self, f: F) -> fmt::Result
- where
- F: FnOnce(&mut Self) -> fmt::Result,
- {
- let backref_parser = parse!(self, backref);
-
- if self.out.is_none() {
- return Ok(());
- }
-
- let orig_parser = mem::replace(&mut self.parser, Ok(backref_parser));
- let r = f(self);
- self.parser = orig_parser;
- r
- }
-
- fn pop_depth(&mut self) {
- if let Ok(ref mut parser) = self.parser {
- parser.pop_depth();
- }
- }
-
- /// Output the given value to `self.out` (using `fmt::Display` formatting),
- /// if printing isn't being skipped.
- fn print(&mut self, x: impl fmt::Display) -> fmt::Result {
- if let Some(out) = &mut self.out {
- fmt::Display::fmt(&x, out)?;
- }
- Ok(())
- }
-
- /// Output the given `char`s (escaped using `char::escape_debug`), with the
- /// whole sequence wrapped in quotes, for either a `char` or `&str` literal,
- /// if printing isn't being skipped.
- fn print_quoted_escaped_chars(
- &mut self,
- quote: char,
- chars: impl Iterator<Item = char>,
- ) -> fmt::Result {
- if let Some(out) = &mut self.out {
- use core::fmt::Write;
-
- out.write_char(quote)?;
- for c in chars {
- // Special-case not escaping a single/double quote, when
- // inside the opposite kind of quote.
- if matches!((quote, c), ('\'', '"') | ('"', '\'')) {
- out.write_char(c)?;
- continue;
- }
-
- for escaped in c.escape_debug() {
- out.write_char(escaped)?;
- }
- }
- out.write_char(quote)?;
- }
- Ok(())
- }
-
- /// Print the lifetime according to the previously decoded index.
- /// An index of `0` always refers to `'_`, but starting with `1`,
- /// indices refer to late-bound lifetimes introduced by a binder.
- fn print_lifetime_from_index(&mut self, lt: u64) -> fmt::Result {
- // Bound lifetimes aren't tracked when skipping printing.
- if self.out.is_none() {
- return Ok(());
- }
-
- self.print("'")?;
- if lt == 0 {
- return self.print("_");
- }
- match (self.bound_lifetime_depth as u64).checked_sub(lt) {
- Some(depth) => {
- // Try to print lifetimes alphabetically first.
- if depth < 26 {
- let c = (b'a' + depth as u8) as char;
- self.print(c)
- } else {
- // Use `'_123` after running out of letters.
- self.print("_")?;
- self.print(depth)
- }
- }
- None => invalid!(self),
- }
- }
-
- /// Optionally enter a binder ('G') for late-bound lifetimes,
- /// printing e.g. `for<'a, 'b> ` before calling the closure,
- /// and make those lifetimes visible to it (via depth level).
- fn in_binder<F>(&mut self, f: F) -> fmt::Result
- where
- F: FnOnce(&mut Self) -> fmt::Result,
- {
- let bound_lifetimes = parse!(self, opt_integer_62(b'G'));
-
- // Don't track bound lifetimes when skipping printing.
- if self.out.is_none() {
- return f(self);
- }
-
- if bound_lifetimes > 0 {
- self.print("for<")?;
- for i in 0..bound_lifetimes {
- if i > 0 {
- self.print(", ")?;
- }
- self.bound_lifetime_depth += 1;
- self.print_lifetime_from_index(1)?;
- }
- self.print("> ")?;
- }
-
- let r = f(self);
-
- // Restore `bound_lifetime_depth` to the previous value.
- self.bound_lifetime_depth -= bound_lifetimes as u32;
-
- r
- }
-
- /// Print list elements using the given closure and separator,
- /// until the end of the list ('E') is found, or the parser errors.
- /// Returns the number of elements printed.
- fn print_sep_list<F>(&mut self, f: F, sep: &str) -> Result<usize, fmt::Error>
- where
- F: Fn(&mut Self) -> fmt::Result,
- {
- let mut i = 0;
- while self.parser.is_ok() && !self.eat(b'E') {
- if i > 0 {
- self.print(sep)?;
- }
- f(self)?;
- i += 1;
- }
- Ok(i)
- }
-
- fn print_path(&mut self, in_value: bool) -> fmt::Result {
- parse!(self, push_depth);
-
- let tag = parse!(self, next);
- match tag {
- b'C' => {
- let dis = parse!(self, disambiguator);
- let name = parse!(self, ident);
-
- self.print(name)?;
- if let Some(out) = &mut self.out {
- if !out.alternate() {
- out.write_str("[")?;
- fmt::LowerHex::fmt(&dis, out)?;
- out.write_str("]")?;
- }
- }
- }
- b'N' => {
- let ns = parse!(self, namespace);
-
- self.print_path(in_value)?;
-
- // HACK(eddyb) if the parser is already marked as having errored,
- // `parse!` below will print a `?` without its preceding `::`
- // (because printing the `::` is skipped in certain conditions,
- // i.e. a lowercase namespace with an empty identifier),
- // so in order to get `::?`, the `::` has to be printed here.
- if self.parser.is_err() {
- self.print("::")?;
- }
-
- let dis = parse!(self, disambiguator);
- let name = parse!(self, ident);
-
- match ns {
- // Special namespaces, like closures and shims.
- Some(ns) => {
- self.print("::{")?;
- match ns {
- 'C' => self.print("closure")?,
- 'S' => self.print("shim")?,
- _ => self.print(ns)?,
- }
- if !name.ascii.is_empty() || !name.punycode.is_empty() {
- self.print(":")?;
- self.print(name)?;
- }
- self.print("#")?;
- self.print(dis)?;
- self.print("}")?;
- }
-
- // Implementation-specific/unspecified namespaces.
- None => {
- if !name.ascii.is_empty() || !name.punycode.is_empty() {
- self.print("::")?;
- self.print(name)?;
- }
- }
- }
- }
- b'M' | b'X' | b'Y' => {
- if tag != b'Y' {
- // Ignore the `impl`'s own path.
- parse!(self, disambiguator);
- self.skipping_printing(|this| this.print_path(false));
- }
-
- self.print("<")?;
- self.print_type()?;
- if tag != b'M' {
- self.print(" as ")?;
- self.print_path(false)?;
- }
- self.print(">")?;
- }
- b'I' => {
- self.print_path(in_value)?;
- if in_value {
- self.print("::")?;
- }
- self.print("<")?;
- self.print_sep_list(Self::print_generic_arg, ", ")?;
- self.print(">")?;
- }
- b'B' => {
- self.print_backref(|this| this.print_path(in_value))?;
- }
- _ => invalid!(self),
- }
-
- self.pop_depth();
- Ok(())
- }
-
- fn print_generic_arg(&mut self) -> fmt::Result {
- if self.eat(b'L') {
- let lt = parse!(self, integer_62);
- self.print_lifetime_from_index(lt)
- } else if self.eat(b'K') {
- self.print_const(false)
- } else {
- self.print_type()
- }
- }
-
- fn print_type(&mut self) -> fmt::Result {
- let tag = parse!(self, next);
-
- if let Some(ty) = basic_type(tag) {
- return self.print(ty);
- }
-
- parse!(self, push_depth);
-
- match tag {
- b'R' | b'Q' => {
- self.print("&")?;
- if self.eat(b'L') {
- let lt = parse!(self, integer_62);
- if lt != 0 {
- self.print_lifetime_from_index(lt)?;
- self.print(" ")?;
- }
- }
- if tag != b'R' {
- self.print("mut ")?;
- }
- self.print_type()?;
- }
-
- b'P' | b'O' => {
- self.print("*")?;
- if tag != b'P' {
- self.print("mut ")?;
- } else {
- self.print("const ")?;
- }
- self.print_type()?;
- }
-
- b'A' | b'S' => {
- self.print("[")?;
- self.print_type()?;
- if tag == b'A' {
- self.print("; ")?;
- self.print_const(true)?;
- }
- self.print("]")?;
- }
- b'T' => {
- self.print("(")?;
- let count = self.print_sep_list(Self::print_type, ", ")?;
- if count == 1 {
- self.print(",")?;
- }
- self.print(")")?;
- }
- b'F' => self.in_binder(|this| {
- let is_unsafe = this.eat(b'U');
- let abi = if this.eat(b'K') {
- if this.eat(b'C') {
- Some("C")
- } else {
- let abi = parse!(this, ident);
- if abi.ascii.is_empty() || !abi.punycode.is_empty() {
- invalid!(this);
- }
- Some(abi.ascii)
- }
- } else {
- None
- };
-
- if is_unsafe {
- this.print("unsafe ")?;
- }
-
- if let Some(abi) = abi {
- this.print("extern \"")?;
-
- // If the ABI had any `-`, they were replaced with `_`,
- // so the parts between `_` have to be re-joined with `-`.
- let mut parts = abi.split('_');
- this.print(parts.next().unwrap())?;
- for part in parts {
- this.print("-")?;
- this.print(part)?;
- }
-
- this.print("\" ")?;
- }
-
- this.print("fn(")?;
- this.print_sep_list(Self::print_type, ", ")?;
- this.print(")")?;
-
- if this.eat(b'u') {
- // Skip printing the return type if it's 'u', i.e. `()`.
- } else {
- this.print(" -> ")?;
- this.print_type()?;
- }
-
- Ok(())
- })?,
- b'D' => {
- self.print("dyn ")?;
- self.in_binder(|this| {
- this.print_sep_list(Self::print_dyn_trait, " + ")?;
- Ok(())
- })?;
-
- if !self.eat(b'L') {
- invalid!(self);
- }
- let lt = parse!(self, integer_62);
- if lt != 0 {
- self.print(" + ")?;
- self.print_lifetime_from_index(lt)?;
- }
- }
- b'B' => {
- self.print_backref(Self::print_type)?;
- }
- _ => {
- // Go back to the tag, so `print_path` also sees it.
- let _ = self.parser.as_mut().map(|p| p.next -= 1);
- self.print_path(false)?;
- }
- }
-
- self.pop_depth();
- Ok(())
- }
-
- /// A trait in a trait object may have some "existential projections"
- /// (i.e. associated type bindings) after it, which should be printed
- /// in the `<...>` of the trait, e.g. `dyn Trait<T, U, Assoc=X>`.
- /// To this end, this method will keep the `<...>` of an 'I' path
- /// open, by omitting the `>`, and return `Ok(true)` in that case.
- fn print_path_maybe_open_generics(&mut self) -> Result<bool, fmt::Error> {
- if self.eat(b'B') {
- // NOTE(eddyb) the closure may not run if printing is being skipped,
- // but in that case the returned boolean doesn't matter.
- let mut open = false;
- self.print_backref(|this| {
- open = this.print_path_maybe_open_generics()?;
- Ok(())
- })?;
- Ok(open)
- } else if self.eat(b'I') {
- self.print_path(false)?;
- self.print("<")?;
- self.print_sep_list(Self::print_generic_arg, ", ")?;
- Ok(true)
- } else {
- self.print_path(false)?;
- Ok(false)
- }
- }
-
- fn print_dyn_trait(&mut self) -> fmt::Result {
- let mut open = self.print_path_maybe_open_generics()?;
-
- while self.eat(b'p') {
- if !open {
- self.print("<")?;
- open = true;
- } else {
- self.print(", ")?;
- }
-
- let name = parse!(self, ident);
- self.print(name)?;
- self.print(" = ")?;
- self.print_type()?;
- }
-
- if open {
- self.print(">")?;
- }
-
- Ok(())
- }
-
- fn print_const(&mut self, in_value: bool) -> fmt::Result {
- let tag = parse!(self, next);
-
- parse!(self, push_depth);
-
- // Only literals (and the names of `const` generic parameters, but they
- // don't get mangled at all), can appear in generic argument position
- // without any disambiguation, all other expressions require braces.
- // To avoid duplicating the mapping between `tag` and what syntax gets
- // used (especially any special-casing), every case that needs braces
- // has to call `open_brace(self)?` (and the closing brace is automatic).
- let mut opened_brace = false;
- let mut open_brace_if_outside_expr = |this: &mut Self| {
- // If this expression is nested in another, braces aren't required.
- if in_value {
- return Ok(());
- }
-
- opened_brace = true;
- this.print("{")
- };
-
- match tag {
- b'p' => self.print("_")?,
-
- // Primitive leaves with hex-encoded values (see `basic_type`).
- b'h' | b't' | b'm' | b'y' | b'o' | b'j' => self.print_const_uint(tag)?,
- b'a' | b's' | b'l' | b'x' | b'n' | b'i' => {
- if self.eat(b'n') {
- self.print("-")?;
- }
-
- self.print_const_uint(tag)?;
- }
- b'b' => match parse!(self, hex_nibbles).try_parse_uint() {
- Some(0) => self.print("false")?,
- Some(1) => self.print("true")?,
- _ => invalid!(self),
- },
- b'c' => {
- let valid_char = parse!(self, hex_nibbles)
- .try_parse_uint()
- .and_then(|v| u32::try_from(v).ok())
- .and_then(char::from_u32);
- match valid_char {
- Some(c) => self.print_quoted_escaped_chars('\'', iter::once(c))?,
- None => invalid!(self),
- }
- }
- b'e' => {
- // NOTE(eddyb) a string literal `"..."` has type `&str`, so
- // to get back the type `str`, `*"..."` syntax is needed
- // (even if that may not be valid in Rust itself).
- open_brace_if_outside_expr(self)?;
- self.print("*")?;
-
- self.print_const_str_literal()?;
- }
-
- b'R' | b'Q' => {
- // NOTE(eddyb) this prints `"..."` instead of `&*"..."`, which
- // is what `Re..._` would imply (see comment for `str` above).
- if tag == b'R' && self.eat(b'e') {
- self.print_const_str_literal()?;
- } else {
- open_brace_if_outside_expr(self)?;
- self.print("&")?;
- if tag != b'R' {
- self.print("mut ")?;
- }
- self.print_const(true)?;
- }
- }
- b'A' => {
- open_brace_if_outside_expr(self)?;
- self.print("[")?;
- self.print_sep_list(|this| this.print_const(true), ", ")?;
- self.print("]")?;
- }
- b'T' => {
- open_brace_if_outside_expr(self)?;
- self.print("(")?;
- let count = self.print_sep_list(|this| this.print_const(true), ", ")?;
- if count == 1 {
- self.print(",")?;
- }
- self.print(")")?;
- }
- b'V' => {
- open_brace_if_outside_expr(self)?;
- self.print_path(true)?;
- match parse!(self, next) {
- b'U' => {}
- b'T' => {
- self.print("(")?;
- self.print_sep_list(|this| this.print_const(true), ", ")?;
- self.print(")")?;
- }
- b'S' => {
- self.print(" { ")?;
- self.print_sep_list(
- |this| {
- parse!(this, disambiguator);
- let name = parse!(this, ident);
- this.print(name)?;
- this.print(": ")?;
- this.print_const(true)
- },
- ", ",
- )?;
- self.print(" }")?;
- }
- _ => invalid!(self),
- }
- }
- b'B' => {
- self.print_backref(|this| this.print_const(in_value))?;
- }
- _ => invalid!(self),
- }
-
- if opened_brace {
- self.print("}")?;
- }
-
- self.pop_depth();
- Ok(())
- }
-
- fn print_const_uint(&mut self, ty_tag: u8) -> fmt::Result {
- let hex = parse!(self, hex_nibbles);
-
- match hex.try_parse_uint() {
- Some(v) => self.print(v)?,
-
- // Print anything that doesn't fit in `u64` verbatim.
- None => {
- self.print("0x")?;
- self.print(hex.nibbles)?;
- }
- }
-
- if let Some(out) = &mut self.out {
- if !out.alternate() {
- let ty = basic_type(ty_tag).unwrap();
- self.print(ty)?;
- }
- }
-
- Ok(())
- }
-
- fn print_const_str_literal(&mut self) -> fmt::Result {
- match parse!(self, hex_nibbles).try_parse_str_chars() {
- Some(chars) => self.print_quoted_escaped_chars('"', chars),
- None => invalid!(self),
- }
- }
-}
-
-#[cfg(test)]
-mod tests {
- use std::prelude::v1::*;
-
- macro_rules! t {
- ($a:expr, $b:expr) => {{
- assert_eq!(format!("{}", ::demangle($a)), $b);
- }};
- }
- macro_rules! t_nohash {
- ($a:expr, $b:expr) => {{
- assert_eq!(format!("{:#}", ::demangle($a)), $b);
- }};
- }
- macro_rules! t_nohash_type {
- ($a:expr, $b:expr) => {
- t_nohash!(concat!("_RMC0", $a), concat!("<", $b, ">"))
- };
- }
- macro_rules! t_const {
- ($mangled:expr, $value:expr) => {
- t_nohash!(
- concat!("_RIC0K", $mangled, "E"),
- concat!("::<", $value, ">")
- )
- };
- }
- macro_rules! t_const_suffixed {
- ($mangled:expr, $value:expr, $value_ty_suffix:expr) => {{
- t_const!($mangled, $value);
- t!(
- concat!("_RIC0K", $mangled, "E"),
- concat!("[0]::<", $value, $value_ty_suffix, ">")
- );
- }};
- }
-
- #[test]
- fn demangle_crate_with_leading_digit() {
- t_nohash!("_RNvC6_123foo3bar", "123foo::bar");
- }
-
- #[test]
- fn demangle_utf8_idents() {
- t_nohash!(
- "_RNqCs4fqI2P2rA04_11utf8_identsu30____7hkackfecea1cbdathfdh9hlq6y",
- "utf8_idents::საჭმელად_გემრიელი_სადილი"
- );
- }
-
- #[test]
- fn demangle_closure() {
- t_nohash!(
- "_RNCNCNgCs6DXkGYLi8lr_2cc5spawn00B5_",
- "cc::spawn::{closure#0}::{closure#0}"
- );
- t_nohash!(
- "_RNCINkXs25_NgCsbmNqQUJIY6D_4core5sliceINyB9_4IterhENuNgNoBb_4iter8iterator8Iterator9rpositionNCNgNpB9_6memchr7memrchrs_0E0Bb_",
- "<core::slice::Iter<u8> as core::iter::iterator::Iterator>::rposition::<core::slice::memchr::memrchr::{closure#1}>::{closure#0}"
- );
- }
-
- #[test]
- fn demangle_dyn_trait() {
- t_nohash!(
- "_RINbNbCskIICzLVDPPb_5alloc5alloc8box_freeDINbNiB4_5boxed5FnBoxuEp6OutputuEL_ECs1iopQbuBiw2_3std",
- "alloc::alloc::box_free::<dyn alloc::boxed::FnBox<(), Output = ()>>"
- );
- }
-
- #[test]
- fn demangle_const_generics_preview() {
- // NOTE(eddyb) this was hand-written, before rustc had working
- // const generics support (but the mangling format did include them).
- t_nohash_type!(
- "INtC8arrayvec8ArrayVechKj7b_E",
- "arrayvec::ArrayVec<u8, 123>"
- );
- t_const_suffixed!("j7b_", "123", "usize");
- }
-
- #[test]
- fn demangle_min_const_generics() {
- t_const!("p", "_");
- t_const_suffixed!("hb_", "11", "u8");
- t_const_suffixed!("off00ff00ff00ff00ff_", "0xff00ff00ff00ff00ff", "u128");
- t_const_suffixed!("s98_", "152", "i16");
- t_const_suffixed!("anb_", "-11", "i8");
- t_const!("b0_", "false");
- t_const!("b1_", "true");
- t_const!("c76_", "'v'");
- t_const!("c22_", r#"'"'"#);
- t_const!("ca_", "'\\n'");
- t_const!("c2202_", "'∂'");
- }
-
- #[test]
- fn demangle_const_str() {
- t_const!("e616263_", "{*\"abc\"}");
- t_const!("e27_", r#"{*"'"}"#);
- t_const!("e090a_", "{*\"\\t\\n\"}");
- t_const!("ee28882c3bc_", "{*\"∂ü\"}");
- t_const!(
- "ee183a1e18390e183ade1839be18394e1839ae18390e183935fe18392e18394e1839b\
- e183a0e18398e18394e1839ae183985fe183a1e18390e18393e18398e1839ae18398_",
- "{*\"საჭმელად_გემრიელი_სადილი\"}"
- );
- t_const!(
- "ef09f908af09fa688f09fa686f09f90ae20c2a720f09f90b6f09f9192e298\
- 95f09f94a520c2a720f09fa7a1f09f929bf09f929af09f9299f09f929c_",
- "{*\"🐊🦈🦆🐮 § 🐶👒☕🔥 § 🧡💛💚💙💜\"}"
- );
- }
-
- // NOTE(eddyb) this uses the same strings as `demangle_const_str` and should
- // be kept in sync with it - while a macro could be used to generate both
- // `str` and `&str` tests, from a single list of strings, this seems clearer.
- #[test]
- fn demangle_const_ref_str() {
- t_const!("Re616263_", "\"abc\"");
- t_const!("Re27_", r#""'""#);
- t_const!("Re090a_", "\"\\t\\n\"");
- t_const!("Ree28882c3bc_", "\"∂ü\"");
- t_const!(
- "Ree183a1e18390e183ade1839be18394e1839ae18390e183935fe18392e18394e1839b\
- e183a0e18398e18394e1839ae183985fe183a1e18390e18393e18398e1839ae18398_",
- "\"საჭმელად_გემრიელი_სადილი\""
- );
- t_const!(
- "Ref09f908af09fa688f09fa686f09f90ae20c2a720f09f90b6f09f9192e298\
- 95f09f94a520c2a720f09fa7a1f09f929bf09f929af09f9299f09f929c_",
- "\"🐊🦈🦆🐮 § 🐶👒☕🔥 § 🧡💛💚💙💜\""
- );
- }
-
- #[test]
- fn demangle_const_ref() {
- t_const!("Rp", "{&_}");
- t_const!("Rh7b_", "{&123}");
- t_const!("Rb0_", "{&false}");
- t_const!("Rc58_", "{&'X'}");
- t_const!("RRRh0_", "{&&&0}");
- t_const!("RRRe_", "{&&\"\"}");
- t_const!("QAE", "{&mut []}");
- }
-
- #[test]
- fn demangle_const_array() {
- t_const!("AE", "{[]}");
- t_const!("Aj0_E", "{[0]}");
- t_const!("Ah1_h2_h3_E", "{[1, 2, 3]}");
- t_const!("ARe61_Re62_Re63_E", "{[\"a\", \"b\", \"c\"]}");
- t_const!("AAh1_h2_EAh3_h4_EE", "{[[1, 2], [3, 4]]}");
- }
-
- #[test]
- fn demangle_const_tuple() {
- t_const!("TE", "{()}");
- t_const!("Tj0_E", "{(0,)}");
- t_const!("Th1_b0_E", "{(1, false)}");
- t_const!(
- "TRe616263_c78_RAh1_h2_h3_EE",
- "{(\"abc\", 'x', &[1, 2, 3])}"
- );
- }
-
- #[test]
- fn demangle_const_adt() {
- t_const!(
- "VNvINtNtC4core6option6OptionjE4NoneU",
- "{core::option::Option::<usize>::None}"
- );
- t_const!(
- "VNvINtNtC4core6option6OptionjE4SomeTj0_E",
- "{core::option::Option::<usize>::Some(0)}"
- );
- t_const!(
- "VNtC3foo3BarS1sRe616263_2chc78_5sliceRAh1_h2_h3_EE",
- "{foo::Bar { s: \"abc\", ch: 'x', slice: &[1, 2, 3] }}"
- );
- }
-
- #[test]
- fn demangle_exponential_explosion() {
- // NOTE(eddyb) because of the prefix added by `t_nohash_type!` is
- // 3 bytes long, `B2_` refers to the start of the type, not `B_`.
- // 6 backrefs (`B8_E` through `B3_E`) result in 2^6 = 64 copies of `_`.
- // Also, because the `p` (`_`) type is after all of the starts of the
- // backrefs, it can be replaced with any other type, independently.
- t_nohash_type!(
- concat!("TTTTTT", "p", "B8_E", "B7_E", "B6_E", "B5_E", "B4_E", "B3_E"),
- "((((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _)))), \
- ((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _))))), \
- (((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _)))), \
- ((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _))))))"
- );
- }
-
- #[test]
- fn demangle_thinlto() {
- t_nohash!("_RC3foo.llvm.9D1C9369", "foo");
- t_nohash!("_RC3foo.llvm.9D1C9369@@16", "foo");
- t_nohash!("_RNvC9backtrace3foo.llvm.A5310EB9", "backtrace::foo");
- }
-
- #[test]
- fn demangle_extra_suffix() {
- // From alexcrichton/rustc-demangle#27:
- t_nohash!(
- "_RNvNtNtNtNtCs92dm3009vxr_4rand4rngs7adapter9reseeding4fork23FORK_HANDLER_REGISTERED.0.0",
- "rand::rngs::adapter::reseeding::fork::FORK_HANDLER_REGISTERED.0.0"
- );
- }
-
- #[test]
- fn demangling_limits() {
- // Stress tests found via fuzzing.
-
- for sym in include_str!("v0-large-test-symbols/early-recursion-limit")
- .lines()
- .filter(|line| !line.is_empty() && !line.starts_with('#'))
- {
- assert_eq!(
- super::demangle(sym).map(|_| ()),
- Err(super::ParseError::RecursedTooDeep)
- );
- }
-
- assert_contains!(
- ::demangle(
- "RIC20tRYIMYNRYFG05_EB5_B_B6_RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR\
- RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRB_E",
- )
- .to_string(),
- "{recursion limit reached}"
- );
- }
-
- #[test]
- fn recursion_limit_leaks() {
- // NOTE(eddyb) this test checks that both paths and types support the
- // recursion limit correctly, i.e. matching `push_depth` and `pop_depth`,
- // and don't leak "recursion levels" and trip the limit.
- // The test inputs are generated on the fly, using a repeated pattern,
- // as hardcoding the actual strings would be too verbose.
- // Also, `MAX_DEPTH` can be directly used, instead of assuming its value.
- for &(sym_leaf, expected_leaf) in &[("p", "_"), ("Rp", "&_"), ("C1x", "x")] {
- let mut sym = format!("_RIC0p");
- let mut expected = format!("::<_");
- for _ in 0..(super::MAX_DEPTH * 2) {
- sym.push_str(sym_leaf);
- expected.push_str(", ");
- expected.push_str(expected_leaf);
- }
- sym.push('E');
- expected.push('>');
-
- t_nohash!(&sym, expected);
- }
- }
-
- #[test]
- fn recursion_limit_backref_free_bypass() {
- // NOTE(eddyb) this test checks that long symbols cannot bypass the
- // recursion limit by not using backrefs, and cause a stack overflow.
-
- // This value was chosen to be high enough that stack overflows were
- // observed even with `cargo test --release`.
- let depth = 100_000;
-
- // In order to hide the long mangling from the initial "shallow" parse,
- // it's nested in an identifier (crate name), preceding its use.
- let mut sym = format!("_RIC{}", depth);
- let backref_start = sym.len() - 2;
- for _ in 0..depth {
- sym.push('R');
- }
-
- // Write a backref to just after the length of the identifier.
- sym.push('B');
- sym.push(char::from_digit((backref_start - 1) as u32, 36).unwrap());
- sym.push('_');
-
- // Close the `I` at the start.
- sym.push('E');
-
- assert_contains!(::demangle(&sym).to_string(), "{recursion limit reached}");
- }
-}
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