349 lines
9.8 KiB
C
349 lines
9.8 KiB
C
/* Demangler for the Rust programming language
|
|
Copyright (C) 2016-2019 Free Software Foundation, Inc.
|
|
Written by David Tolnay (dtolnay@gmail.com).
|
|
|
|
This file is part of the libiberty library.
|
|
Libiberty is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2 of the License, or (at your option) any later version.
|
|
|
|
In addition to the permissions in the GNU Library General Public
|
|
License, the Free Software Foundation gives you unlimited permission
|
|
to link the compiled version of this file into combinations with other
|
|
programs, and to distribute those combinations without any restriction
|
|
coming from the use of this file. (The Library Public License
|
|
restrictions do apply in other respects; for example, they cover
|
|
modification of the file, and distribution when not linked into a
|
|
combined executable.)
|
|
|
|
Libiberty is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with libiberty; see the file COPYING.LIB.
|
|
If not, see <http://www.gnu.org/licenses/>. */
|
|
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include "safe-ctype.h"
|
|
|
|
#include <sys/types.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
|
|
#ifdef HAVE_STRING_H
|
|
#include <string.h>
|
|
#else
|
|
extern size_t strlen(const char *s);
|
|
extern int strncmp(const char *s1, const char *s2, size_t n);
|
|
extern void *memset(void *s, int c, size_t n);
|
|
#endif
|
|
|
|
#include <demangle.h>
|
|
#include "libiberty.h"
|
|
|
|
|
|
/* Mangled Rust symbols look like this:
|
|
_$LT$std..sys..fd..FileDesc$u20$as$u20$core..ops..Drop$GT$::drop::hc68340e1baa4987a
|
|
|
|
The original symbol is:
|
|
<std::sys::fd::FileDesc as core::ops::Drop>::drop
|
|
|
|
The last component of the path is a 64-bit hash in lowercase hex,
|
|
prefixed with "h". Rust does not have a global namespace between
|
|
crates, an illusion which Rust maintains by using the hash to
|
|
distinguish things that would otherwise have the same symbol.
|
|
|
|
Any path component not starting with a XID_Start character is
|
|
prefixed with "_".
|
|
|
|
The following escape sequences are used:
|
|
|
|
"," => $C$
|
|
"@" => $SP$
|
|
"*" => $BP$
|
|
"&" => $RF$
|
|
"<" => $LT$
|
|
">" => $GT$
|
|
"(" => $LP$
|
|
")" => $RP$
|
|
" " => $u20$
|
|
"\"" => $u22$
|
|
"'" => $u27$
|
|
"+" => $u2b$
|
|
";" => $u3b$
|
|
"[" => $u5b$
|
|
"]" => $u5d$
|
|
"{" => $u7b$
|
|
"}" => $u7d$
|
|
"~" => $u7e$
|
|
|
|
A double ".." means "::" and a single "." means "-".
|
|
|
|
The only characters allowed in the mangled symbol are a-zA-Z0-9 and _.:$ */
|
|
|
|
static const char *hash_prefix = "::h";
|
|
static const size_t hash_prefix_len = 3;
|
|
static const size_t hash_len = 16;
|
|
|
|
static int is_prefixed_hash (const char *start);
|
|
static int looks_like_rust (const char *sym, size_t len);
|
|
static int unescape (const char **in, char **out, const char *seq, char value);
|
|
|
|
/* INPUT: sym: symbol that has been through C++ (gnu v3) demangling
|
|
|
|
This function looks for the following indicators:
|
|
|
|
1. The hash must consist of "h" followed by 16 lowercase hex digits.
|
|
|
|
2. As a sanity check, the hash must use between 5 and 15 of the 16
|
|
possible hex digits. This is true of 99.9998% of hashes so once
|
|
in your life you may see a false negative. The point is to
|
|
notice path components that could be Rust hashes but are
|
|
probably not, like "haaaaaaaaaaaaaaaa". In this case a false
|
|
positive (non-Rust symbol has an important path component
|
|
removed because it looks like a Rust hash) is worse than a false
|
|
negative (the rare Rust symbol is not demangled) so this sets
|
|
the balance in favor of false negatives.
|
|
|
|
3. There must be no characters other than a-zA-Z0-9 and _.:$
|
|
|
|
4. There must be no unrecognized $-sign sequences.
|
|
|
|
5. There must be no sequence of three or more dots in a row ("..."). */
|
|
|
|
int
|
|
rust_is_mangled (const char *sym)
|
|
{
|
|
size_t len, len_without_hash;
|
|
|
|
if (!sym)
|
|
return 0;
|
|
|
|
len = strlen (sym);
|
|
if (len <= hash_prefix_len + hash_len)
|
|
/* Not long enough to contain "::h" + hash + something else */
|
|
return 0;
|
|
|
|
len_without_hash = len - (hash_prefix_len + hash_len);
|
|
if (!is_prefixed_hash (sym + len_without_hash))
|
|
return 0;
|
|
|
|
return looks_like_rust (sym, len_without_hash);
|
|
}
|
|
|
|
/* A hash is the prefix "::h" followed by 16 lowercase hex digits. The
|
|
hex digits must comprise between 5 and 15 (inclusive) distinct
|
|
digits. */
|
|
|
|
static int
|
|
is_prefixed_hash (const char *str)
|
|
{
|
|
const char *end;
|
|
char seen[16];
|
|
size_t i;
|
|
int count;
|
|
|
|
if (strncmp (str, hash_prefix, hash_prefix_len))
|
|
return 0;
|
|
str += hash_prefix_len;
|
|
|
|
memset (seen, 0, sizeof(seen));
|
|
for (end = str + hash_len; str < end; str++)
|
|
if (*str >= '0' && *str <= '9')
|
|
seen[*str - '0'] = 1;
|
|
else if (*str >= 'a' && *str <= 'f')
|
|
seen[*str - 'a' + 10] = 1;
|
|
else
|
|
return 0;
|
|
|
|
/* Count how many distinct digits seen */
|
|
count = 0;
|
|
for (i = 0; i < 16; i++)
|
|
if (seen[i])
|
|
count++;
|
|
|
|
return count >= 5 && count <= 15;
|
|
}
|
|
|
|
static int
|
|
looks_like_rust (const char *str, size_t len)
|
|
{
|
|
const char *end = str + len;
|
|
|
|
while (str < end)
|
|
switch (*str)
|
|
{
|
|
case '$':
|
|
if (!strncmp (str, "$C$", 3))
|
|
str += 3;
|
|
else if (!strncmp (str, "$SP$", 4)
|
|
|| !strncmp (str, "$BP$", 4)
|
|
|| !strncmp (str, "$RF$", 4)
|
|
|| !strncmp (str, "$LT$", 4)
|
|
|| !strncmp (str, "$GT$", 4)
|
|
|| !strncmp (str, "$LP$", 4)
|
|
|| !strncmp (str, "$RP$", 4))
|
|
str += 4;
|
|
else if (!strncmp (str, "$u20$", 5)
|
|
|| !strncmp (str, "$u22$", 5)
|
|
|| !strncmp (str, "$u27$", 5)
|
|
|| !strncmp (str, "$u2b$", 5)
|
|
|| !strncmp (str, "$u3b$", 5)
|
|
|| !strncmp (str, "$u5b$", 5)
|
|
|| !strncmp (str, "$u5d$", 5)
|
|
|| !strncmp (str, "$u7b$", 5)
|
|
|| !strncmp (str, "$u7d$", 5)
|
|
|| !strncmp (str, "$u7e$", 5))
|
|
str += 5;
|
|
else
|
|
return 0;
|
|
break;
|
|
case '.':
|
|
/* Do not allow three or more consecutive dots */
|
|
if (!strncmp (str, "...", 3))
|
|
return 0;
|
|
/* Fall through */
|
|
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
|
|
case 'g': case 'h': case 'i': case 'j': case 'k': case 'l':
|
|
case 'm': case 'n': case 'o': case 'p': case 'q': case 'r':
|
|
case 's': case 't': case 'u': case 'v': case 'w': case 'x':
|
|
case 'y': case 'z':
|
|
case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
|
|
case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
|
|
case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
|
|
case 'S': case 'T': case 'U': case 'V': case 'W': case 'X':
|
|
case 'Y': case 'Z':
|
|
case '0': case '1': case '2': case '3': case '4': case '5':
|
|
case '6': case '7': case '8': case '9':
|
|
case '_':
|
|
case ':':
|
|
str++;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
INPUT: sym: symbol for which rust_is_mangled(sym) returned 1.
|
|
|
|
The input is demangled in-place because the mangled name is always
|
|
longer than the demangled one. */
|
|
|
|
void
|
|
rust_demangle_sym (char *sym)
|
|
{
|
|
const char *in;
|
|
char *out;
|
|
const char *end;
|
|
|
|
if (!sym)
|
|
return;
|
|
|
|
in = sym;
|
|
out = sym;
|
|
end = sym + strlen (sym) - (hash_prefix_len + hash_len);
|
|
|
|
while (in < end)
|
|
switch (*in)
|
|
{
|
|
case '$':
|
|
if (!(unescape (&in, &out, "$C$", ',')
|
|
|| unescape (&in, &out, "$SP$", '@')
|
|
|| unescape (&in, &out, "$BP$", '*')
|
|
|| unescape (&in, &out, "$RF$", '&')
|
|
|| unescape (&in, &out, "$LT$", '<')
|
|
|| unescape (&in, &out, "$GT$", '>')
|
|
|| unescape (&in, &out, "$LP$", '(')
|
|
|| unescape (&in, &out, "$RP$", ')')
|
|
|| unescape (&in, &out, "$u20$", ' ')
|
|
|| unescape (&in, &out, "$u22$", '\"')
|
|
|| unescape (&in, &out, "$u27$", '\'')
|
|
|| unescape (&in, &out, "$u2b$", '+')
|
|
|| unescape (&in, &out, "$u3b$", ';')
|
|
|| unescape (&in, &out, "$u5b$", '[')
|
|
|| unescape (&in, &out, "$u5d$", ']')
|
|
|| unescape (&in, &out, "$u7b$", '{')
|
|
|| unescape (&in, &out, "$u7d$", '}')
|
|
|| unescape (&in, &out, "$u7e$", '~'))) {
|
|
/* unexpected escape sequence, not looks_like_rust. */
|
|
goto fail;
|
|
}
|
|
break;
|
|
case '_':
|
|
/* If this is the start of a path component and the next
|
|
character is an escape sequence, ignore the underscore. The
|
|
mangler inserts an underscore to make sure the path
|
|
component begins with a XID_Start character. */
|
|
if ((in == sym || in[-1] == ':') && in[1] == '$')
|
|
in++;
|
|
else
|
|
*out++ = *in++;
|
|
break;
|
|
case '.':
|
|
if (in[1] == '.')
|
|
{
|
|
/* ".." becomes "::" */
|
|
*out++ = ':';
|
|
*out++ = ':';
|
|
in += 2;
|
|
}
|
|
else
|
|
{
|
|
/* "." becomes "-" */
|
|
*out++ = '-';
|
|
in++;
|
|
}
|
|
break;
|
|
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
|
|
case 'g': case 'h': case 'i': case 'j': case 'k': case 'l':
|
|
case 'm': case 'n': case 'o': case 'p': case 'q': case 'r':
|
|
case 's': case 't': case 'u': case 'v': case 'w': case 'x':
|
|
case 'y': case 'z':
|
|
case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
|
|
case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
|
|
case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
|
|
case 'S': case 'T': case 'U': case 'V': case 'W': case 'X':
|
|
case 'Y': case 'Z':
|
|
case '0': case '1': case '2': case '3': case '4': case '5':
|
|
case '6': case '7': case '8': case '9':
|
|
case ':':
|
|
*out++ = *in++;
|
|
break;
|
|
default:
|
|
/* unexpected character in symbol, not looks_like_rust. */
|
|
goto fail;
|
|
}
|
|
goto done;
|
|
|
|
fail:
|
|
*out++ = '?'; /* This is pretty lame, but it's hard to do better. */
|
|
done:
|
|
*out = '\0';
|
|
}
|
|
|
|
static int
|
|
unescape (const char **in, char **out, const char *seq, char value)
|
|
{
|
|
size_t len = strlen (seq);
|
|
|
|
if (strncmp (*in, seq, len))
|
|
return 0;
|
|
|
|
**out = value;
|
|
|
|
*in += len;
|
|
*out += 1;
|
|
|
|
return 1;
|
|
}
|