1960 lines
65 KiB
C++
1960 lines
65 KiB
C++
// Copyright 2018 The Abseil Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// https://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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// For reference check out:
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// https://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling
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//
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// Note that we only have partial C++11 support yet.
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#include "absl/debugging/internal/demangle.h"
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#include <cstdint>
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#include <cstdio>
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#include <limits>
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namespace absl {
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ABSL_NAMESPACE_BEGIN
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namespace debugging_internal {
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typedef struct {
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const char *abbrev;
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const char *real_name;
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// Number of arguments in <expression> context, or 0 if disallowed.
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int arity;
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} AbbrevPair;
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// List of operators from Itanium C++ ABI.
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static const AbbrevPair kOperatorList[] = {
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// New has special syntax (not currently supported).
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{"nw", "new", 0},
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{"na", "new[]", 0},
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// Works except that the 'gs' prefix is not supported.
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{"dl", "delete", 1},
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{"da", "delete[]", 1},
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{"ps", "+", 1}, // "positive"
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{"ng", "-", 1}, // "negative"
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{"ad", "&", 1}, // "address-of"
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{"de", "*", 1}, // "dereference"
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{"co", "~", 1},
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{"pl", "+", 2},
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{"mi", "-", 2},
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{"ml", "*", 2},
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{"dv", "/", 2},
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{"rm", "%", 2},
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{"an", "&", 2},
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{"or", "|", 2},
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{"eo", "^", 2},
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{"aS", "=", 2},
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{"pL", "+=", 2},
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{"mI", "-=", 2},
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{"mL", "*=", 2},
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{"dV", "/=", 2},
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{"rM", "%=", 2},
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{"aN", "&=", 2},
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{"oR", "|=", 2},
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{"eO", "^=", 2},
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{"ls", "<<", 2},
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{"rs", ">>", 2},
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{"lS", "<<=", 2},
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{"rS", ">>=", 2},
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{"eq", "==", 2},
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{"ne", "!=", 2},
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{"lt", "<", 2},
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{"gt", ">", 2},
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{"le", "<=", 2},
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{"ge", ">=", 2},
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{"nt", "!", 1},
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{"aa", "&&", 2},
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{"oo", "||", 2},
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{"pp", "++", 1},
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{"mm", "--", 1},
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{"cm", ",", 2},
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{"pm", "->*", 2},
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{"pt", "->", 0}, // Special syntax
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{"cl", "()", 0}, // Special syntax
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{"ix", "[]", 2},
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{"qu", "?", 3},
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{"st", "sizeof", 0}, // Special syntax
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{"sz", "sizeof", 1}, // Not a real operator name, but used in expressions.
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{nullptr, nullptr, 0},
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};
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// List of builtin types from Itanium C++ ABI.
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//
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// Invariant: only one- or two-character type abbreviations here.
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static const AbbrevPair kBuiltinTypeList[] = {
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{"v", "void", 0},
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{"w", "wchar_t", 0},
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{"b", "bool", 0},
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{"c", "char", 0},
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{"a", "signed char", 0},
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{"h", "unsigned char", 0},
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{"s", "short", 0},
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{"t", "unsigned short", 0},
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{"i", "int", 0},
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{"j", "unsigned int", 0},
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{"l", "long", 0},
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{"m", "unsigned long", 0},
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{"x", "long long", 0},
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{"y", "unsigned long long", 0},
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{"n", "__int128", 0},
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{"o", "unsigned __int128", 0},
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{"f", "float", 0},
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{"d", "double", 0},
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{"e", "long double", 0},
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{"g", "__float128", 0},
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{"z", "ellipsis", 0},
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{"De", "decimal128", 0}, // IEEE 754r decimal floating point (128 bits)
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{"Dd", "decimal64", 0}, // IEEE 754r decimal floating point (64 bits)
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{"Dc", "decltype(auto)", 0},
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{"Da", "auto", 0},
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{"Dn", "std::nullptr_t", 0}, // i.e., decltype(nullptr)
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{"Df", "decimal32", 0}, // IEEE 754r decimal floating point (32 bits)
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{"Di", "char32_t", 0},
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{"Du", "char8_t", 0},
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{"Ds", "char16_t", 0},
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{"Dh", "float16", 0}, // IEEE 754r half-precision float (16 bits)
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{nullptr, nullptr, 0},
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};
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// List of substitutions Itanium C++ ABI.
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static const AbbrevPair kSubstitutionList[] = {
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{"St", "", 0},
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{"Sa", "allocator", 0},
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{"Sb", "basic_string", 0},
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// std::basic_string<char, std::char_traits<char>,std::allocator<char> >
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{"Ss", "string", 0},
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// std::basic_istream<char, std::char_traits<char> >
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{"Si", "istream", 0},
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// std::basic_ostream<char, std::char_traits<char> >
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{"So", "ostream", 0},
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// std::basic_iostream<char, std::char_traits<char> >
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{"Sd", "iostream", 0},
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{nullptr, nullptr, 0},
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};
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// State needed for demangling. This struct is copied in almost every stack
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// frame, so every byte counts.
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typedef struct {
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int mangled_idx; // Cursor of mangled name.
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int out_cur_idx; // Cursor of output string.
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int prev_name_idx; // For constructors/destructors.
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signed int prev_name_length : 16; // For constructors/destructors.
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signed int nest_level : 15; // For nested names.
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unsigned int append : 1; // Append flag.
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// Note: for some reason MSVC can't pack "bool append : 1" into the same int
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// with the above two fields, so we use an int instead. Amusingly it can pack
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// "signed bool" as expected, but relying on that to continue to be a legal
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// type seems ill-advised (as it's illegal in at least clang).
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} ParseState;
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static_assert(sizeof(ParseState) == 4 * sizeof(int),
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"unexpected size of ParseState");
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// One-off state for demangling that's not subject to backtracking -- either
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// constant data, data that's intentionally immune to backtracking (steps), or
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// data that would never be changed by backtracking anyway (recursion_depth).
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//
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// Only one copy of this exists for each call to Demangle, so the size of this
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// struct is nearly inconsequential.
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typedef struct {
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const char *mangled_begin; // Beginning of input string.
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char *out; // Beginning of output string.
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int out_end_idx; // One past last allowed output character.
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int recursion_depth; // For stack exhaustion prevention.
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int steps; // Cap how much work we'll do, regardless of depth.
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ParseState parse_state; // Backtrackable state copied for most frames.
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} State;
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namespace {
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// Prevent deep recursion / stack exhaustion.
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// Also prevent unbounded handling of complex inputs.
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class ComplexityGuard {
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public:
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explicit ComplexityGuard(State *state) : state_(state) {
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++state->recursion_depth;
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++state->steps;
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}
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~ComplexityGuard() { --state_->recursion_depth; }
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// 256 levels of recursion seems like a reasonable upper limit on depth.
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// 128 is not enough to demagle synthetic tests from demangle_unittest.txt:
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// "_ZaaZZZZ..." and "_ZaaZcvZcvZ..."
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static constexpr int kRecursionDepthLimit = 256;
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// We're trying to pick a charitable upper-limit on how many parse steps are
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// necessary to handle something that a human could actually make use of.
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// This is mostly in place as a bound on how much work we'll do if we are
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// asked to demangle an mangled name from an untrusted source, so it should be
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// much larger than the largest expected symbol, but much smaller than the
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// amount of work we can do in, e.g., a second.
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//
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// Some real-world symbols from an arbitrary binary started failing between
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// 2^12 and 2^13, so we multiply the latter by an extra factor of 16 to set
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// the limit.
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//
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// Spending one second on 2^17 parse steps would require each step to take
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// 7.6us, or ~30000 clock cycles, so it's safe to say this can be done in
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// under a second.
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static constexpr int kParseStepsLimit = 1 << 17;
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bool IsTooComplex() const {
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return state_->recursion_depth > kRecursionDepthLimit ||
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state_->steps > kParseStepsLimit;
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}
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private:
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State *state_;
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};
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} // namespace
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// We don't use strlen() in libc since it's not guaranteed to be async
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// signal safe.
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static size_t StrLen(const char *str) {
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size_t len = 0;
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while (*str != '\0') {
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++str;
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++len;
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}
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return len;
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}
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// Returns true if "str" has at least "n" characters remaining.
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static bool AtLeastNumCharsRemaining(const char *str, int n) {
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for (int i = 0; i < n; ++i) {
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if (str[i] == '\0') {
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return false;
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}
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}
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return true;
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}
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// Returns true if "str" has "prefix" as a prefix.
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static bool StrPrefix(const char *str, const char *prefix) {
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size_t i = 0;
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while (str[i] != '\0' && prefix[i] != '\0' && str[i] == prefix[i]) {
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++i;
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}
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return prefix[i] == '\0'; // Consumed everything in "prefix".
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}
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static void InitState(State *state, const char *mangled, char *out,
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int out_size) {
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state->mangled_begin = mangled;
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state->out = out;
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state->out_end_idx = out_size;
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state->recursion_depth = 0;
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state->steps = 0;
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state->parse_state.mangled_idx = 0;
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state->parse_state.out_cur_idx = 0;
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state->parse_state.prev_name_idx = 0;
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state->parse_state.prev_name_length = -1;
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state->parse_state.nest_level = -1;
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state->parse_state.append = true;
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}
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static inline const char *RemainingInput(State *state) {
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return &state->mangled_begin[state->parse_state.mangled_idx];
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}
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// Returns true and advances "mangled_idx" if we find "one_char_token"
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// at "mangled_idx" position. It is assumed that "one_char_token" does
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// not contain '\0'.
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static bool ParseOneCharToken(State *state, const char one_char_token) {
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ComplexityGuard guard(state);
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if (guard.IsTooComplex()) return false;
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if (RemainingInput(state)[0] == one_char_token) {
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++state->parse_state.mangled_idx;
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return true;
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}
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return false;
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}
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// Returns true and advances "mangled_cur" if we find "two_char_token"
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// at "mangled_cur" position. It is assumed that "two_char_token" does
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// not contain '\0'.
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static bool ParseTwoCharToken(State *state, const char *two_char_token) {
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ComplexityGuard guard(state);
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if (guard.IsTooComplex()) return false;
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if (RemainingInput(state)[0] == two_char_token[0] &&
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RemainingInput(state)[1] == two_char_token[1]) {
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state->parse_state.mangled_idx += 2;
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return true;
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}
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return false;
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}
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// Returns true and advances "mangled_cur" if we find any character in
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// "char_class" at "mangled_cur" position.
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static bool ParseCharClass(State *state, const char *char_class) {
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ComplexityGuard guard(state);
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if (guard.IsTooComplex()) return false;
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if (RemainingInput(state)[0] == '\0') {
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return false;
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}
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const char *p = char_class;
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for (; *p != '\0'; ++p) {
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if (RemainingInput(state)[0] == *p) {
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++state->parse_state.mangled_idx;
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return true;
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}
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}
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return false;
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}
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static bool ParseDigit(State *state, int *digit) {
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char c = RemainingInput(state)[0];
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if (ParseCharClass(state, "0123456789")) {
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if (digit != nullptr) {
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*digit = c - '0';
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}
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return true;
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}
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return false;
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}
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// This function is used for handling an optional non-terminal.
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static bool Optional(bool /*status*/) { return true; }
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// This function is used for handling <non-terminal>+ syntax.
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typedef bool (*ParseFunc)(State *);
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static bool OneOrMore(ParseFunc parse_func, State *state) {
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if (parse_func(state)) {
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while (parse_func(state)) {
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}
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return true;
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}
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return false;
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}
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// This function is used for handling <non-terminal>* syntax. The function
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// always returns true and must be followed by a termination token or a
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// terminating sequence not handled by parse_func (e.g.
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// ParseOneCharToken(state, 'E')).
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static bool ZeroOrMore(ParseFunc parse_func, State *state) {
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while (parse_func(state)) {
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}
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return true;
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}
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// Append "str" at "out_cur_idx". If there is an overflow, out_cur_idx is
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// set to out_end_idx+1. The output string is ensured to
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// always terminate with '\0' as long as there is no overflow.
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static void Append(State *state, const char *const str, const int length) {
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for (int i = 0; i < length; ++i) {
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if (state->parse_state.out_cur_idx + 1 <
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state->out_end_idx) { // +1 for '\0'
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state->out[state->parse_state.out_cur_idx++] = str[i];
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} else {
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// signal overflow
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state->parse_state.out_cur_idx = state->out_end_idx + 1;
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break;
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}
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}
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if (state->parse_state.out_cur_idx < state->out_end_idx) {
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state->out[state->parse_state.out_cur_idx] =
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'\0'; // Terminate it with '\0'
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}
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}
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// We don't use equivalents in libc to avoid locale issues.
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static bool IsLower(char c) { return c >= 'a' && c <= 'z'; }
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static bool IsAlpha(char c) {
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return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
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}
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static bool IsDigit(char c) { return c >= '0' && c <= '9'; }
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// Returns true if "str" is a function clone suffix. These suffixes are used
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// by GCC 4.5.x and later versions (and our locally-modified version of GCC
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// 4.4.x) to indicate functions which have been cloned during optimization.
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// We treat any sequence (.<alpha>+.<digit>+)+ as a function clone suffix.
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// Additionally, '_' is allowed along with the alphanumeric sequence.
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static bool IsFunctionCloneSuffix(const char *str) {
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size_t i = 0;
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while (str[i] != '\0') {
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bool parsed = false;
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// Consume a single [.<alpha> | _]*[.<digit>]* sequence.
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if (str[i] == '.' && (IsAlpha(str[i + 1]) || str[i + 1] == '_')) {
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parsed = true;
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i += 2;
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while (IsAlpha(str[i]) || str[i] == '_') {
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++i;
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}
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}
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if (str[i] == '.' && IsDigit(str[i + 1])) {
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parsed = true;
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i += 2;
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while (IsDigit(str[i])) {
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++i;
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}
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}
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if (!parsed)
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return false;
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}
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return true; // Consumed everything in "str".
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}
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static bool EndsWith(State *state, const char chr) {
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return state->parse_state.out_cur_idx > 0 &&
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state->parse_state.out_cur_idx < state->out_end_idx &&
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chr == state->out[state->parse_state.out_cur_idx - 1];
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}
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// Append "str" with some tweaks, iff "append" state is true.
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static void MaybeAppendWithLength(State *state, const char *const str,
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const int length) {
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if (state->parse_state.append && length > 0) {
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// Append a space if the output buffer ends with '<' and "str"
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// starts with '<' to avoid <<<.
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if (str[0] == '<' && EndsWith(state, '<')) {
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Append(state, " ", 1);
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}
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// Remember the last identifier name for ctors/dtors,
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// but only if we haven't yet overflown the buffer.
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if (state->parse_state.out_cur_idx < state->out_end_idx &&
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(IsAlpha(str[0]) || str[0] == '_')) {
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state->parse_state.prev_name_idx = state->parse_state.out_cur_idx;
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state->parse_state.prev_name_length = length;
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}
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Append(state, str, length);
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}
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}
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// Appends a positive decimal number to the output if appending is enabled.
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static bool MaybeAppendDecimal(State *state, unsigned int val) {
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// Max {32-64}-bit unsigned int is 20 digits.
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constexpr size_t kMaxLength = 20;
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char buf[kMaxLength];
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// We can't use itoa or sprintf as neither is specified to be
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// async-signal-safe.
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if (state->parse_state.append) {
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// We can't have a one-before-the-beginning pointer, so instead start with
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// one-past-the-end and manipulate one character before the pointer.
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char *p = &buf[kMaxLength];
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do { // val=0 is the only input that should write a leading zero digit.
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*--p = (val % 10) + '0';
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val /= 10;
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} while (p > buf && val != 0);
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// 'p' landed on the last character we set. How convenient.
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Append(state, p, kMaxLength - (p - buf));
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}
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return true;
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}
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// A convenient wrapper around MaybeAppendWithLength().
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// Returns true so that it can be placed in "if" conditions.
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static bool MaybeAppend(State *state, const char *const str) {
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if (state->parse_state.append) {
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int length = StrLen(str);
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MaybeAppendWithLength(state, str, length);
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}
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return true;
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}
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// This function is used for handling nested names.
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static bool EnterNestedName(State *state) {
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state->parse_state.nest_level = 0;
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return true;
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}
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// This function is used for handling nested names.
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|
static bool LeaveNestedName(State *state, int16_t prev_value) {
|
|
state->parse_state.nest_level = prev_value;
|
|
return true;
|
|
}
|
|
|
|
// Disable the append mode not to print function parameters, etc.
|
|
static bool DisableAppend(State *state) {
|
|
state->parse_state.append = false;
|
|
return true;
|
|
}
|
|
|
|
// Restore the append mode to the previous state.
|
|
static bool RestoreAppend(State *state, bool prev_value) {
|
|
state->parse_state.append = prev_value;
|
|
return true;
|
|
}
|
|
|
|
// Increase the nest level for nested names.
|
|
static void MaybeIncreaseNestLevel(State *state) {
|
|
if (state->parse_state.nest_level > -1) {
|
|
++state->parse_state.nest_level;
|
|
}
|
|
}
|
|
|
|
// Appends :: for nested names if necessary.
|
|
static void MaybeAppendSeparator(State *state) {
|
|
if (state->parse_state.nest_level >= 1) {
|
|
MaybeAppend(state, "::");
|
|
}
|
|
}
|
|
|
|
// Cancel the last separator if necessary.
|
|
static void MaybeCancelLastSeparator(State *state) {
|
|
if (state->parse_state.nest_level >= 1 && state->parse_state.append &&
|
|
state->parse_state.out_cur_idx >= 2) {
|
|
state->parse_state.out_cur_idx -= 2;
|
|
state->out[state->parse_state.out_cur_idx] = '\0';
|
|
}
|
|
}
|
|
|
|
// Returns true if the identifier of the given length pointed to by
|
|
// "mangled_cur" is anonymous namespace.
|
|
static bool IdentifierIsAnonymousNamespace(State *state, int length) {
|
|
// Returns true if "anon_prefix" is a proper prefix of "mangled_cur".
|
|
static const char anon_prefix[] = "_GLOBAL__N_";
|
|
return (length > static_cast<int>(sizeof(anon_prefix) - 1) &&
|
|
StrPrefix(RemainingInput(state), anon_prefix));
|
|
}
|
|
|
|
// Forward declarations of our parsing functions.
|
|
static bool ParseMangledName(State *state);
|
|
static bool ParseEncoding(State *state);
|
|
static bool ParseName(State *state);
|
|
static bool ParseUnscopedName(State *state);
|
|
static bool ParseNestedName(State *state);
|
|
static bool ParsePrefix(State *state);
|
|
static bool ParseUnqualifiedName(State *state);
|
|
static bool ParseSourceName(State *state);
|
|
static bool ParseLocalSourceName(State *state);
|
|
static bool ParseUnnamedTypeName(State *state);
|
|
static bool ParseNumber(State *state, int *number_out);
|
|
static bool ParseFloatNumber(State *state);
|
|
static bool ParseSeqId(State *state);
|
|
static bool ParseIdentifier(State *state, int length);
|
|
static bool ParseOperatorName(State *state, int *arity);
|
|
static bool ParseSpecialName(State *state);
|
|
static bool ParseCallOffset(State *state);
|
|
static bool ParseNVOffset(State *state);
|
|
static bool ParseVOffset(State *state);
|
|
static bool ParseCtorDtorName(State *state);
|
|
static bool ParseDecltype(State *state);
|
|
static bool ParseType(State *state);
|
|
static bool ParseCVQualifiers(State *state);
|
|
static bool ParseBuiltinType(State *state);
|
|
static bool ParseFunctionType(State *state);
|
|
static bool ParseBareFunctionType(State *state);
|
|
static bool ParseClassEnumType(State *state);
|
|
static bool ParseArrayType(State *state);
|
|
static bool ParsePointerToMemberType(State *state);
|
|
static bool ParseTemplateParam(State *state);
|
|
static bool ParseTemplateTemplateParam(State *state);
|
|
static bool ParseTemplateArgs(State *state);
|
|
static bool ParseTemplateArg(State *state);
|
|
static bool ParseBaseUnresolvedName(State *state);
|
|
static bool ParseUnresolvedName(State *state);
|
|
static bool ParseExpression(State *state);
|
|
static bool ParseExprPrimary(State *state);
|
|
static bool ParseExprCastValue(State *state);
|
|
static bool ParseLocalName(State *state);
|
|
static bool ParseLocalNameSuffix(State *state);
|
|
static bool ParseDiscriminator(State *state);
|
|
static bool ParseSubstitution(State *state, bool accept_std);
|
|
|
|
// Implementation note: the following code is a straightforward
|
|
// translation of the Itanium C++ ABI defined in BNF with a couple of
|
|
// exceptions.
|
|
//
|
|
// - Support GNU extensions not defined in the Itanium C++ ABI
|
|
// - <prefix> and <template-prefix> are combined to avoid infinite loop
|
|
// - Reorder patterns to shorten the code
|
|
// - Reorder patterns to give greedier functions precedence
|
|
// We'll mark "Less greedy than" for these cases in the code
|
|
//
|
|
// Each parsing function changes the parse state and returns true on
|
|
// success, or returns false and doesn't change the parse state (note:
|
|
// the parse-steps counter increases regardless of success or failure).
|
|
// To ensure that the parse state isn't changed in the latter case, we
|
|
// save the original state before we call multiple parsing functions
|
|
// consecutively with &&, and restore it if unsuccessful. See
|
|
// ParseEncoding() as an example of this convention. We follow the
|
|
// convention throughout the code.
|
|
//
|
|
// Originally we tried to do demangling without following the full ABI
|
|
// syntax but it turned out we needed to follow the full syntax to
|
|
// parse complicated cases like nested template arguments. Note that
|
|
// implementing a full-fledged demangler isn't trivial (libiberty's
|
|
// cp-demangle.c has +4300 lines).
|
|
//
|
|
// Note that (foo) in <(foo) ...> is a modifier to be ignored.
|
|
//
|
|
// Reference:
|
|
// - Itanium C++ ABI
|
|
// <https://mentorembedded.github.io/cxx-abi/abi.html#mangling>
|
|
|
|
// <mangled-name> ::= _Z <encoding>
|
|
static bool ParseMangledName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
return ParseTwoCharToken(state, "_Z") && ParseEncoding(state);
|
|
}
|
|
|
|
// <encoding> ::= <(function) name> <bare-function-type>
|
|
// ::= <(data) name>
|
|
// ::= <special-name>
|
|
static bool ParseEncoding(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
// Implementing the first two productions together as <name>
|
|
// [<bare-function-type>] avoids exponential blowup of backtracking.
|
|
//
|
|
// Since Optional(...) can't fail, there's no need to copy the state for
|
|
// backtracking.
|
|
if (ParseName(state) && Optional(ParseBareFunctionType(state))) {
|
|
return true;
|
|
}
|
|
|
|
if (ParseSpecialName(state)) {
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// <name> ::= <nested-name>
|
|
// ::= <unscoped-template-name> <template-args>
|
|
// ::= <unscoped-name>
|
|
// ::= <local-name>
|
|
static bool ParseName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (ParseNestedName(state) || ParseLocalName(state)) {
|
|
return true;
|
|
}
|
|
|
|
// We reorganize the productions to avoid re-parsing unscoped names.
|
|
// - Inline <unscoped-template-name> productions:
|
|
// <name> ::= <substitution> <template-args>
|
|
// ::= <unscoped-name> <template-args>
|
|
// ::= <unscoped-name>
|
|
// - Merge the two productions that start with unscoped-name:
|
|
// <name> ::= <unscoped-name> [<template-args>]
|
|
|
|
ParseState copy = state->parse_state;
|
|
// "std<...>" isn't a valid name.
|
|
if (ParseSubstitution(state, /*accept_std=*/false) &&
|
|
ParseTemplateArgs(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Note there's no need to restore state after this since only the first
|
|
// subparser can fail.
|
|
return ParseUnscopedName(state) && Optional(ParseTemplateArgs(state));
|
|
}
|
|
|
|
// <unscoped-name> ::= <unqualified-name>
|
|
// ::= St <unqualified-name>
|
|
static bool ParseUnscopedName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (ParseUnqualifiedName(state)) {
|
|
return true;
|
|
}
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseTwoCharToken(state, "St") && MaybeAppend(state, "std::") &&
|
|
ParseUnqualifiedName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <ref-qualifer> ::= R // lvalue method reference qualifier
|
|
// ::= O // rvalue method reference qualifier
|
|
static inline bool ParseRefQualifier(State *state) {
|
|
return ParseCharClass(state, "OR");
|
|
}
|
|
|
|
// <nested-name> ::= N [<CV-qualifiers>] [<ref-qualifier>] <prefix>
|
|
// <unqualified-name> E
|
|
// ::= N [<CV-qualifiers>] [<ref-qualifier>] <template-prefix>
|
|
// <template-args> E
|
|
static bool ParseNestedName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'N') && EnterNestedName(state) &&
|
|
Optional(ParseCVQualifiers(state)) &&
|
|
Optional(ParseRefQualifier(state)) && ParsePrefix(state) &&
|
|
LeaveNestedName(state, copy.nest_level) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// This part is tricky. If we literally translate them to code, we'll
|
|
// end up infinite loop. Hence we merge them to avoid the case.
|
|
//
|
|
// <prefix> ::= <prefix> <unqualified-name>
|
|
// ::= <template-prefix> <template-args>
|
|
// ::= <template-param>
|
|
// ::= <substitution>
|
|
// ::= # empty
|
|
// <template-prefix> ::= <prefix> <(template) unqualified-name>
|
|
// ::= <template-param>
|
|
// ::= <substitution>
|
|
static bool ParsePrefix(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
bool has_something = false;
|
|
while (true) {
|
|
MaybeAppendSeparator(state);
|
|
if (ParseTemplateParam(state) ||
|
|
ParseSubstitution(state, /*accept_std=*/true) ||
|
|
ParseUnscopedName(state) ||
|
|
(ParseOneCharToken(state, 'M') && ParseUnnamedTypeName(state))) {
|
|
has_something = true;
|
|
MaybeIncreaseNestLevel(state);
|
|
continue;
|
|
}
|
|
MaybeCancelLastSeparator(state);
|
|
if (has_something && ParseTemplateArgs(state)) {
|
|
return ParsePrefix(state);
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
// <unqualified-name> ::= <operator-name>
|
|
// ::= <ctor-dtor-name>
|
|
// ::= <source-name>
|
|
// ::= <local-source-name> // GCC extension; see below.
|
|
// ::= <unnamed-type-name>
|
|
static bool ParseUnqualifiedName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
return (ParseOperatorName(state, nullptr) || ParseCtorDtorName(state) ||
|
|
ParseSourceName(state) || ParseLocalSourceName(state) ||
|
|
ParseUnnamedTypeName(state));
|
|
}
|
|
|
|
// <source-name> ::= <positive length number> <identifier>
|
|
static bool ParseSourceName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
int length = -1;
|
|
if (ParseNumber(state, &length) && ParseIdentifier(state, length)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <local-source-name> ::= L <source-name> [<discriminator>]
|
|
//
|
|
// References:
|
|
// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=31775
|
|
// https://gcc.gnu.org/viewcvs?view=rev&revision=124467
|
|
static bool ParseLocalSourceName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'L') && ParseSourceName(state) &&
|
|
Optional(ParseDiscriminator(state))) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <unnamed-type-name> ::= Ut [<(nonnegative) number>] _
|
|
// ::= <closure-type-name>
|
|
// <closure-type-name> ::= Ul <lambda-sig> E [<(nonnegative) number>] _
|
|
// <lambda-sig> ::= <(parameter) type>+
|
|
static bool ParseUnnamedTypeName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
// Type's 1-based index n is encoded as { "", n == 1; itoa(n-2), otherwise }.
|
|
// Optionally parse the encoded value into 'which' and add 2 to get the index.
|
|
int which = -1;
|
|
|
|
// Unnamed type local to function or class.
|
|
if (ParseTwoCharToken(state, "Ut") && Optional(ParseNumber(state, &which)) &&
|
|
which <= std::numeric_limits<int>::max() - 2 && // Don't overflow.
|
|
ParseOneCharToken(state, '_')) {
|
|
MaybeAppend(state, "{unnamed type#");
|
|
MaybeAppendDecimal(state, 2 + which);
|
|
MaybeAppend(state, "}");
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Closure type.
|
|
which = -1;
|
|
if (ParseTwoCharToken(state, "Ul") && DisableAppend(state) &&
|
|
OneOrMore(ParseType, state) && RestoreAppend(state, copy.append) &&
|
|
ParseOneCharToken(state, 'E') && Optional(ParseNumber(state, &which)) &&
|
|
which <= std::numeric_limits<int>::max() - 2 && // Don't overflow.
|
|
ParseOneCharToken(state, '_')) {
|
|
MaybeAppend(state, "{lambda()#");
|
|
MaybeAppendDecimal(state, 2 + which);
|
|
MaybeAppend(state, "}");
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <number> ::= [n] <non-negative decimal integer>
|
|
// If "number_out" is non-null, then *number_out is set to the value of the
|
|
// parsed number on success.
|
|
static bool ParseNumber(State *state, int *number_out) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
bool negative = false;
|
|
if (ParseOneCharToken(state, 'n')) {
|
|
negative = true;
|
|
}
|
|
const char *p = RemainingInput(state);
|
|
uint64_t number = 0;
|
|
for (; *p != '\0'; ++p) {
|
|
if (IsDigit(*p)) {
|
|
number = number * 10 + (*p - '0');
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
// Apply the sign with uint64_t arithmetic so overflows aren't UB. Gives
|
|
// "incorrect" results for out-of-range inputs, but negative values only
|
|
// appear for literals, which aren't printed.
|
|
if (negative) {
|
|
number = ~number + 1;
|
|
}
|
|
if (p != RemainingInput(state)) { // Conversion succeeded.
|
|
state->parse_state.mangled_idx += p - RemainingInput(state);
|
|
if (number_out != nullptr) {
|
|
// Note: possibly truncate "number".
|
|
*number_out = number;
|
|
}
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// Floating-point literals are encoded using a fixed-length lowercase
|
|
// hexadecimal string.
|
|
static bool ParseFloatNumber(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
const char *p = RemainingInput(state);
|
|
for (; *p != '\0'; ++p) {
|
|
if (!IsDigit(*p) && !(*p >= 'a' && *p <= 'f')) {
|
|
break;
|
|
}
|
|
}
|
|
if (p != RemainingInput(state)) { // Conversion succeeded.
|
|
state->parse_state.mangled_idx += p - RemainingInput(state);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// The <seq-id> is a sequence number in base 36,
|
|
// using digits and upper case letters
|
|
static bool ParseSeqId(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
const char *p = RemainingInput(state);
|
|
for (; *p != '\0'; ++p) {
|
|
if (!IsDigit(*p) && !(*p >= 'A' && *p <= 'Z')) {
|
|
break;
|
|
}
|
|
}
|
|
if (p != RemainingInput(state)) { // Conversion succeeded.
|
|
state->parse_state.mangled_idx += p - RemainingInput(state);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// <identifier> ::= <unqualified source code identifier> (of given length)
|
|
static bool ParseIdentifier(State *state, int length) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (length < 0 || !AtLeastNumCharsRemaining(RemainingInput(state), length)) {
|
|
return false;
|
|
}
|
|
if (IdentifierIsAnonymousNamespace(state, length)) {
|
|
MaybeAppend(state, "(anonymous namespace)");
|
|
} else {
|
|
MaybeAppendWithLength(state, RemainingInput(state), length);
|
|
}
|
|
state->parse_state.mangled_idx += length;
|
|
return true;
|
|
}
|
|
|
|
// <operator-name> ::= nw, and other two letters cases
|
|
// ::= cv <type> # (cast)
|
|
// ::= v <digit> <source-name> # vendor extended operator
|
|
static bool ParseOperatorName(State *state, int *arity) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (!AtLeastNumCharsRemaining(RemainingInput(state), 2)) {
|
|
return false;
|
|
}
|
|
// First check with "cv" (cast) case.
|
|
ParseState copy = state->parse_state;
|
|
if (ParseTwoCharToken(state, "cv") && MaybeAppend(state, "operator ") &&
|
|
EnterNestedName(state) && ParseType(state) &&
|
|
LeaveNestedName(state, copy.nest_level)) {
|
|
if (arity != nullptr) {
|
|
*arity = 1;
|
|
}
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Then vendor extended operators.
|
|
if (ParseOneCharToken(state, 'v') && ParseDigit(state, arity) &&
|
|
ParseSourceName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Other operator names should start with a lower alphabet followed
|
|
// by a lower/upper alphabet.
|
|
if (!(IsLower(RemainingInput(state)[0]) &&
|
|
IsAlpha(RemainingInput(state)[1]))) {
|
|
return false;
|
|
}
|
|
// We may want to perform a binary search if we really need speed.
|
|
const AbbrevPair *p;
|
|
for (p = kOperatorList; p->abbrev != nullptr; ++p) {
|
|
if (RemainingInput(state)[0] == p->abbrev[0] &&
|
|
RemainingInput(state)[1] == p->abbrev[1]) {
|
|
if (arity != nullptr) {
|
|
*arity = p->arity;
|
|
}
|
|
MaybeAppend(state, "operator");
|
|
if (IsLower(*p->real_name)) { // new, delete, etc.
|
|
MaybeAppend(state, " ");
|
|
}
|
|
MaybeAppend(state, p->real_name);
|
|
state->parse_state.mangled_idx += 2;
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// <special-name> ::= TV <type>
|
|
// ::= TT <type>
|
|
// ::= TI <type>
|
|
// ::= TS <type>
|
|
// ::= TH <type> # thread-local
|
|
// ::= Tc <call-offset> <call-offset> <(base) encoding>
|
|
// ::= GV <(object) name>
|
|
// ::= T <call-offset> <(base) encoding>
|
|
// G++ extensions:
|
|
// ::= TC <type> <(offset) number> _ <(base) type>
|
|
// ::= TF <type>
|
|
// ::= TJ <type>
|
|
// ::= GR <name>
|
|
// ::= GA <encoding>
|
|
// ::= Th <call-offset> <(base) encoding>
|
|
// ::= Tv <call-offset> <(base) encoding>
|
|
//
|
|
// Note: we don't care much about them since they don't appear in
|
|
// stack traces. The are special data.
|
|
static bool ParseSpecialName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'T') && ParseCharClass(state, "VTISH") &&
|
|
ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "Tc") && ParseCallOffset(state) &&
|
|
ParseCallOffset(state) && ParseEncoding(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "GV") && ParseName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'T') && ParseCallOffset(state) &&
|
|
ParseEncoding(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// G++ extensions
|
|
if (ParseTwoCharToken(state, "TC") && ParseType(state) &&
|
|
ParseNumber(state, nullptr) && ParseOneCharToken(state, '_') &&
|
|
DisableAppend(state) && ParseType(state)) {
|
|
RestoreAppend(state, copy.append);
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'T') && ParseCharClass(state, "FJ") &&
|
|
ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "GR") && ParseName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "GA") && ParseEncoding(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'T') && ParseCharClass(state, "hv") &&
|
|
ParseCallOffset(state) && ParseEncoding(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <call-offset> ::= h <nv-offset> _
|
|
// ::= v <v-offset> _
|
|
static bool ParseCallOffset(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'h') && ParseNVOffset(state) &&
|
|
ParseOneCharToken(state, '_')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'v') && ParseVOffset(state) &&
|
|
ParseOneCharToken(state, '_')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <nv-offset> ::= <(offset) number>
|
|
static bool ParseNVOffset(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
return ParseNumber(state, nullptr);
|
|
}
|
|
|
|
// <v-offset> ::= <(offset) number> _ <(virtual offset) number>
|
|
static bool ParseVOffset(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseNumber(state, nullptr) && ParseOneCharToken(state, '_') &&
|
|
ParseNumber(state, nullptr)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <ctor-dtor-name> ::= C1 | C2 | C3 | CI1 <base-class-type> | CI2
|
|
// <base-class-type>
|
|
// ::= D0 | D1 | D2
|
|
// # GCC extensions: "unified" constructor/destructor. See
|
|
// #
|
|
// https://github.com/gcc-mirror/gcc/blob/7ad17b583c3643bd4557f29b8391ca7ef08391f5/gcc/cp/mangle.c#L1847
|
|
// ::= C4 | D4
|
|
static bool ParseCtorDtorName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'C')) {
|
|
if (ParseCharClass(state, "1234")) {
|
|
const char *const prev_name =
|
|
state->out + state->parse_state.prev_name_idx;
|
|
MaybeAppendWithLength(state, prev_name,
|
|
state->parse_state.prev_name_length);
|
|
return true;
|
|
} else if (ParseOneCharToken(state, 'I') && ParseCharClass(state, "12") &&
|
|
ParseClassEnumType(state)) {
|
|
return true;
|
|
}
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'D') && ParseCharClass(state, "0124")) {
|
|
const char *const prev_name = state->out + state->parse_state.prev_name_idx;
|
|
MaybeAppend(state, "~");
|
|
MaybeAppendWithLength(state, prev_name,
|
|
state->parse_state.prev_name_length);
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <decltype> ::= Dt <expression> E # decltype of an id-expression or class
|
|
// # member access (C++0x)
|
|
// ::= DT <expression> E # decltype of an expression (C++0x)
|
|
static bool ParseDecltype(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'D') && ParseCharClass(state, "tT") &&
|
|
ParseExpression(state) && ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <type> ::= <CV-qualifiers> <type>
|
|
// ::= P <type> # pointer-to
|
|
// ::= R <type> # reference-to
|
|
// ::= O <type> # rvalue reference-to (C++0x)
|
|
// ::= C <type> # complex pair (C 2000)
|
|
// ::= G <type> # imaginary (C 2000)
|
|
// ::= U <source-name> <type> # vendor extended type qualifier
|
|
// ::= <builtin-type>
|
|
// ::= <function-type>
|
|
// ::= <class-enum-type> # note: just an alias for <name>
|
|
// ::= <array-type>
|
|
// ::= <pointer-to-member-type>
|
|
// ::= <template-template-param> <template-args>
|
|
// ::= <template-param>
|
|
// ::= <decltype>
|
|
// ::= <substitution>
|
|
// ::= Dp <type> # pack expansion of (C++0x)
|
|
// ::= Dv <num-elems> _ # GNU vector extension
|
|
//
|
|
static bool ParseType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
|
|
// We should check CV-qualifers, and PRGC things first.
|
|
//
|
|
// CV-qualifiers overlap with some operator names, but an operator name is not
|
|
// valid as a type. To avoid an ambiguity that can lead to exponential time
|
|
// complexity, refuse to backtrack the CV-qualifiers.
|
|
//
|
|
// _Z4aoeuIrMvvE
|
|
// => _Z 4aoeuI rM v v E
|
|
// aoeu<operator%=, void, void>
|
|
// => _Z 4aoeuI r Mv v E
|
|
// aoeu<void void::* restrict>
|
|
//
|
|
// By consuming the CV-qualifiers first, the former parse is disabled.
|
|
if (ParseCVQualifiers(state)) {
|
|
const bool result = ParseType(state);
|
|
if (!result) state->parse_state = copy;
|
|
return result;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Similarly, these tag characters can overlap with other <name>s resulting in
|
|
// two different parse prefixes that land on <template-args> in the same
|
|
// place, such as "C3r1xI...". So, disable the "ctor-name = C3" parse by
|
|
// refusing to backtrack the tag characters.
|
|
if (ParseCharClass(state, "OPRCG")) {
|
|
const bool result = ParseType(state);
|
|
if (!result) state->parse_state = copy;
|
|
return result;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "Dp") && ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'U') && ParseSourceName(state) &&
|
|
ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseBuiltinType(state) || ParseFunctionType(state) ||
|
|
ParseClassEnumType(state) || ParseArrayType(state) ||
|
|
ParsePointerToMemberType(state) || ParseDecltype(state) ||
|
|
// "std" on its own isn't a type.
|
|
ParseSubstitution(state, /*accept_std=*/false)) {
|
|
return true;
|
|
}
|
|
|
|
if (ParseTemplateTemplateParam(state) && ParseTemplateArgs(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Less greedy than <template-template-param> <template-args>.
|
|
if (ParseTemplateParam(state)) {
|
|
return true;
|
|
}
|
|
|
|
if (ParseTwoCharToken(state, "Dv") && ParseNumber(state, nullptr) &&
|
|
ParseOneCharToken(state, '_')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <CV-qualifiers> ::= [r] [V] [K]
|
|
// We don't allow empty <CV-qualifiers> to avoid infinite loop in
|
|
// ParseType().
|
|
static bool ParseCVQualifiers(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
int num_cv_qualifiers = 0;
|
|
num_cv_qualifiers += ParseOneCharToken(state, 'r');
|
|
num_cv_qualifiers += ParseOneCharToken(state, 'V');
|
|
num_cv_qualifiers += ParseOneCharToken(state, 'K');
|
|
return num_cv_qualifiers > 0;
|
|
}
|
|
|
|
// <builtin-type> ::= v, etc. # single-character builtin types
|
|
// ::= u <source-name>
|
|
// ::= Dd, etc. # two-character builtin types
|
|
//
|
|
// Not supported:
|
|
// ::= DF <number> _ # _FloatN (N bits)
|
|
//
|
|
static bool ParseBuiltinType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
const AbbrevPair *p;
|
|
for (p = kBuiltinTypeList; p->abbrev != nullptr; ++p) {
|
|
// Guaranteed only 1- or 2-character strings in kBuiltinTypeList.
|
|
if (p->abbrev[1] == '\0') {
|
|
if (ParseOneCharToken(state, p->abbrev[0])) {
|
|
MaybeAppend(state, p->real_name);
|
|
return true;
|
|
}
|
|
} else if (p->abbrev[2] == '\0' && ParseTwoCharToken(state, p->abbrev)) {
|
|
MaybeAppend(state, p->real_name);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'u') && ParseSourceName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <exception-spec> ::= Do # non-throwing
|
|
// exception-specification (e.g.,
|
|
// noexcept, throw())
|
|
// ::= DO <expression> E # computed (instantiation-dependent)
|
|
// noexcept
|
|
// ::= Dw <type>+ E # dynamic exception specification
|
|
// with instantiation-dependent types
|
|
static bool ParseExceptionSpec(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
|
|
if (ParseTwoCharToken(state, "Do")) return true;
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseTwoCharToken(state, "DO") && ParseExpression(state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
if (ParseTwoCharToken(state, "Dw") && OneOrMore(ParseType, state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <function-type> ::= [exception-spec] F [Y] <bare-function-type> [O] E
|
|
static bool ParseFunctionType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (Optional(ParseExceptionSpec(state)) && ParseOneCharToken(state, 'F') &&
|
|
Optional(ParseOneCharToken(state, 'Y')) && ParseBareFunctionType(state) &&
|
|
Optional(ParseOneCharToken(state, 'O')) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <bare-function-type> ::= <(signature) type>+
|
|
static bool ParseBareFunctionType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
DisableAppend(state);
|
|
if (OneOrMore(ParseType, state)) {
|
|
RestoreAppend(state, copy.append);
|
|
MaybeAppend(state, "()");
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <class-enum-type> ::= <name>
|
|
static bool ParseClassEnumType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
return ParseName(state);
|
|
}
|
|
|
|
// <array-type> ::= A <(positive dimension) number> _ <(element) type>
|
|
// ::= A [<(dimension) expression>] _ <(element) type>
|
|
static bool ParseArrayType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'A') && ParseNumber(state, nullptr) &&
|
|
ParseOneCharToken(state, '_') && ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'A') && Optional(ParseExpression(state)) &&
|
|
ParseOneCharToken(state, '_') && ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <pointer-to-member-type> ::= M <(class) type> <(member) type>
|
|
static bool ParsePointerToMemberType(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'M') && ParseType(state) && ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <template-param> ::= T_
|
|
// ::= T <parameter-2 non-negative number> _
|
|
static bool ParseTemplateParam(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (ParseTwoCharToken(state, "T_")) {
|
|
MaybeAppend(state, "?"); // We don't support template substitutions.
|
|
return true;
|
|
}
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'T') && ParseNumber(state, nullptr) &&
|
|
ParseOneCharToken(state, '_')) {
|
|
MaybeAppend(state, "?"); // We don't support template substitutions.
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <template-template-param> ::= <template-param>
|
|
// ::= <substitution>
|
|
static bool ParseTemplateTemplateParam(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
return (ParseTemplateParam(state) ||
|
|
// "std" on its own isn't a template.
|
|
ParseSubstitution(state, /*accept_std=*/false));
|
|
}
|
|
|
|
// <template-args> ::= I <template-arg>+ E
|
|
static bool ParseTemplateArgs(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
DisableAppend(state);
|
|
if (ParseOneCharToken(state, 'I') && OneOrMore(ParseTemplateArg, state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
RestoreAppend(state, copy.append);
|
|
MaybeAppend(state, "<>");
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <template-arg> ::= <type>
|
|
// ::= <expr-primary>
|
|
// ::= J <template-arg>* E # argument pack
|
|
// ::= X <expression> E
|
|
static bool ParseTemplateArg(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'J') && ZeroOrMore(ParseTemplateArg, state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// There can be significant overlap between the following leading to
|
|
// exponential backtracking:
|
|
//
|
|
// <expr-primary> ::= L <type> <expr-cast-value> E
|
|
// e.g. L 2xxIvE 1 E
|
|
// <type> ==> <local-source-name> <template-args>
|
|
// e.g. L 2xx IvE
|
|
//
|
|
// This means parsing an entire <type> twice, and <type> can contain
|
|
// <template-arg>, so this can generate exponential backtracking. There is
|
|
// only overlap when the remaining input starts with "L <source-name>", so
|
|
// parse all cases that can start this way jointly to share the common prefix.
|
|
//
|
|
// We have:
|
|
//
|
|
// <template-arg> ::= <type>
|
|
// ::= <expr-primary>
|
|
//
|
|
// First, drop all the productions of <type> that must start with something
|
|
// other than 'L'. All that's left is <class-enum-type>; inline it.
|
|
//
|
|
// <type> ::= <nested-name> # starts with 'N'
|
|
// ::= <unscoped-name>
|
|
// ::= <unscoped-template-name> <template-args>
|
|
// ::= <local-name> # starts with 'Z'
|
|
//
|
|
// Drop and inline again:
|
|
//
|
|
// <type> ::= <unscoped-name>
|
|
// ::= <unscoped-name> <template-args>
|
|
// ::= <substitution> <template-args> # starts with 'S'
|
|
//
|
|
// Merge the first two, inline <unscoped-name>, drop last:
|
|
//
|
|
// <type> ::= <unqualified-name> [<template-args>]
|
|
// ::= St <unqualified-name> [<template-args>] # starts with 'S'
|
|
//
|
|
// Drop and inline:
|
|
//
|
|
// <type> ::= <operator-name> [<template-args>] # starts with lowercase
|
|
// ::= <ctor-dtor-name> [<template-args>] # starts with 'C' or 'D'
|
|
// ::= <source-name> [<template-args>] # starts with digit
|
|
// ::= <local-source-name> [<template-args>]
|
|
// ::= <unnamed-type-name> [<template-args>] # starts with 'U'
|
|
//
|
|
// One more time:
|
|
//
|
|
// <type> ::= L <source-name> [<template-args>]
|
|
//
|
|
// Likewise with <expr-primary>:
|
|
//
|
|
// <expr-primary> ::= L <type> <expr-cast-value> E
|
|
// ::= LZ <encoding> E # cannot overlap; drop
|
|
// ::= L <mangled_name> E # cannot overlap; drop
|
|
//
|
|
// By similar reasoning as shown above, the only <type>s starting with
|
|
// <source-name> are "<source-name> [<template-args>]". Inline this.
|
|
//
|
|
// <expr-primary> ::= L <source-name> [<template-args>] <expr-cast-value> E
|
|
//
|
|
// Now inline both of these into <template-arg>:
|
|
//
|
|
// <template-arg> ::= L <source-name> [<template-args>]
|
|
// ::= L <source-name> [<template-args>] <expr-cast-value> E
|
|
//
|
|
// Merge them and we're done:
|
|
// <template-arg>
|
|
// ::= L <source-name> [<template-args>] [<expr-cast-value> E]
|
|
if (ParseLocalSourceName(state) && Optional(ParseTemplateArgs(state))) {
|
|
copy = state->parse_state;
|
|
if (ParseExprCastValue(state) && ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return true;
|
|
}
|
|
|
|
// Now that the overlapping cases can't reach this code, we can safely call
|
|
// both of these.
|
|
if (ParseType(state) || ParseExprPrimary(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'X') && ParseExpression(state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <unresolved-type> ::= <template-param> [<template-args>]
|
|
// ::= <decltype>
|
|
// ::= <substitution>
|
|
static inline bool ParseUnresolvedType(State *state) {
|
|
// No ComplexityGuard because we don't copy the state in this stack frame.
|
|
return (ParseTemplateParam(state) && Optional(ParseTemplateArgs(state))) ||
|
|
ParseDecltype(state) || ParseSubstitution(state, /*accept_std=*/false);
|
|
}
|
|
|
|
// <simple-id> ::= <source-name> [<template-args>]
|
|
static inline bool ParseSimpleId(State *state) {
|
|
// No ComplexityGuard because we don't copy the state in this stack frame.
|
|
|
|
// Note: <simple-id> cannot be followed by a parameter pack; see comment in
|
|
// ParseUnresolvedType.
|
|
return ParseSourceName(state) && Optional(ParseTemplateArgs(state));
|
|
}
|
|
|
|
// <base-unresolved-name> ::= <source-name> [<template-args>]
|
|
// ::= on <operator-name> [<template-args>]
|
|
// ::= dn <destructor-name>
|
|
static bool ParseBaseUnresolvedName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
|
|
if (ParseSimpleId(state)) {
|
|
return true;
|
|
}
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseTwoCharToken(state, "on") && ParseOperatorName(state, nullptr) &&
|
|
Optional(ParseTemplateArgs(state))) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "dn") &&
|
|
(ParseUnresolvedType(state) || ParseSimpleId(state))) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <unresolved-name> ::= [gs] <base-unresolved-name>
|
|
// ::= sr <unresolved-type> <base-unresolved-name>
|
|
// ::= srN <unresolved-type> <unresolved-qualifier-level>+ E
|
|
// <base-unresolved-name>
|
|
// ::= [gs] sr <unresolved-qualifier-level>+ E
|
|
// <base-unresolved-name>
|
|
static bool ParseUnresolvedName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (Optional(ParseTwoCharToken(state, "gs")) &&
|
|
ParseBaseUnresolvedName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "sr") && ParseUnresolvedType(state) &&
|
|
ParseBaseUnresolvedName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseTwoCharToken(state, "sr") && ParseOneCharToken(state, 'N') &&
|
|
ParseUnresolvedType(state) &&
|
|
OneOrMore(/* <unresolved-qualifier-level> ::= */ ParseSimpleId, state) &&
|
|
ParseOneCharToken(state, 'E') && ParseBaseUnresolvedName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (Optional(ParseTwoCharToken(state, "gs")) &&
|
|
ParseTwoCharToken(state, "sr") &&
|
|
OneOrMore(/* <unresolved-qualifier-level> ::= */ ParseSimpleId, state) &&
|
|
ParseOneCharToken(state, 'E') && ParseBaseUnresolvedName(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <expression> ::= <1-ary operator-name> <expression>
|
|
// ::= <2-ary operator-name> <expression> <expression>
|
|
// ::= <3-ary operator-name> <expression> <expression> <expression>
|
|
// ::= cl <expression>+ E
|
|
// ::= cp <simple-id> <expression>* E # Clang-specific.
|
|
// ::= cv <type> <expression> # type (expression)
|
|
// ::= cv <type> _ <expression>* E # type (expr-list)
|
|
// ::= st <type>
|
|
// ::= <template-param>
|
|
// ::= <function-param>
|
|
// ::= <expr-primary>
|
|
// ::= dt <expression> <unresolved-name> # expr.name
|
|
// ::= pt <expression> <unresolved-name> # expr->name
|
|
// ::= sp <expression> # argument pack expansion
|
|
// ::= sr <type> <unqualified-name> <template-args>
|
|
// ::= sr <type> <unqualified-name>
|
|
// <function-param> ::= fp <(top-level) CV-qualifiers> _
|
|
// ::= fp <(top-level) CV-qualifiers> <number> _
|
|
// ::= fL <number> p <(top-level) CV-qualifiers> _
|
|
// ::= fL <number> p <(top-level) CV-qualifiers> <number> _
|
|
static bool ParseExpression(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (ParseTemplateParam(state) || ParseExprPrimary(state)) {
|
|
return true;
|
|
}
|
|
|
|
ParseState copy = state->parse_state;
|
|
|
|
// Object/function call expression.
|
|
if (ParseTwoCharToken(state, "cl") && OneOrMore(ParseExpression, state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Clang-specific "cp <simple-id> <expression>* E"
|
|
// https://clang.llvm.org/doxygen/ItaniumMangle_8cpp_source.html#l04338
|
|
if (ParseTwoCharToken(state, "cp") && ParseSimpleId(state) &&
|
|
ZeroOrMore(ParseExpression, state) && ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Function-param expression (level 0).
|
|
if (ParseTwoCharToken(state, "fp") && Optional(ParseCVQualifiers(state)) &&
|
|
Optional(ParseNumber(state, nullptr)) && ParseOneCharToken(state, '_')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Function-param expression (level 1+).
|
|
if (ParseTwoCharToken(state, "fL") && Optional(ParseNumber(state, nullptr)) &&
|
|
ParseOneCharToken(state, 'p') && Optional(ParseCVQualifiers(state)) &&
|
|
Optional(ParseNumber(state, nullptr)) && ParseOneCharToken(state, '_')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Parse the conversion expressions jointly to avoid re-parsing the <type> in
|
|
// their common prefix. Parsed as:
|
|
// <expression> ::= cv <type> <conversion-args>
|
|
// <conversion-args> ::= _ <expression>* E
|
|
// ::= <expression>
|
|
//
|
|
// Also don't try ParseOperatorName after seeing "cv", since ParseOperatorName
|
|
// also needs to accept "cv <type>" in other contexts.
|
|
if (ParseTwoCharToken(state, "cv")) {
|
|
if (ParseType(state)) {
|
|
ParseState copy2 = state->parse_state;
|
|
if (ParseOneCharToken(state, '_') && ZeroOrMore(ParseExpression, state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy2;
|
|
if (ParseExpression(state)) {
|
|
return true;
|
|
}
|
|
}
|
|
} else {
|
|
// Parse unary, binary, and ternary operator expressions jointly, taking
|
|
// care not to re-parse subexpressions repeatedly. Parse like:
|
|
// <expression> ::= <operator-name> <expression>
|
|
// [<one-to-two-expressions>]
|
|
// <one-to-two-expressions> ::= <expression> [<expression>]
|
|
int arity = -1;
|
|
if (ParseOperatorName(state, &arity) &&
|
|
arity > 0 && // 0 arity => disabled.
|
|
(arity < 3 || ParseExpression(state)) &&
|
|
(arity < 2 || ParseExpression(state)) &&
|
|
(arity < 1 || ParseExpression(state))) {
|
|
return true;
|
|
}
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// sizeof type
|
|
if (ParseTwoCharToken(state, "st") && ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Object and pointer member access expressions.
|
|
if ((ParseTwoCharToken(state, "dt") || ParseTwoCharToken(state, "pt")) &&
|
|
ParseExpression(state) && ParseType(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Pointer-to-member access expressions. This parses the same as a binary
|
|
// operator, but it's implemented separately because "ds" shouldn't be
|
|
// accepted in other contexts that parse an operator name.
|
|
if (ParseTwoCharToken(state, "ds") && ParseExpression(state) &&
|
|
ParseExpression(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Parameter pack expansion
|
|
if (ParseTwoCharToken(state, "sp") && ParseExpression(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return ParseUnresolvedName(state);
|
|
}
|
|
|
|
// <expr-primary> ::= L <type> <(value) number> E
|
|
// ::= L <type> <(value) float> E
|
|
// ::= L <mangled-name> E
|
|
// // A bug in g++'s C++ ABI version 2 (-fabi-version=2).
|
|
// ::= LZ <encoding> E
|
|
//
|
|
// Warning, subtle: the "bug" LZ production above is ambiguous with the first
|
|
// production where <type> starts with <local-name>, which can lead to
|
|
// exponential backtracking in two scenarios:
|
|
//
|
|
// - When whatever follows the E in the <local-name> in the first production is
|
|
// not a name, we backtrack the whole <encoding> and re-parse the whole thing.
|
|
//
|
|
// - When whatever follows the <local-name> in the first production is not a
|
|
// number and this <expr-primary> may be followed by a name, we backtrack the
|
|
// <name> and re-parse it.
|
|
//
|
|
// Moreover this ambiguity isn't always resolved -- for example, the following
|
|
// has two different parses:
|
|
//
|
|
// _ZaaILZ4aoeuE1x1EvE
|
|
// => operator&&<aoeu, x, E, void>
|
|
// => operator&&<(aoeu::x)(1), void>
|
|
//
|
|
// To resolve this, we just do what GCC's demangler does, and refuse to parse
|
|
// casts to <local-name> types.
|
|
static bool ParseExprPrimary(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
|
|
// The "LZ" special case: if we see LZ, we commit to accept "LZ <encoding> E"
|
|
// or fail, no backtracking.
|
|
if (ParseTwoCharToken(state, "LZ")) {
|
|
if (ParseEncoding(state) && ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// The merged cast production.
|
|
if (ParseOneCharToken(state, 'L') && ParseType(state) &&
|
|
ParseExprCastValue(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseOneCharToken(state, 'L') && ParseMangledName(state) &&
|
|
ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <number> or <float>, followed by 'E', as described above ParseExprPrimary.
|
|
static bool ParseExprCastValue(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
// We have to be able to backtrack after accepting a number because we could
|
|
// have e.g. "7fffE", which will accept "7" as a number but then fail to find
|
|
// the 'E'.
|
|
ParseState copy = state->parse_state;
|
|
if (ParseNumber(state, nullptr) && ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
if (ParseFloatNumber(state) && ParseOneCharToken(state, 'E')) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
return false;
|
|
}
|
|
|
|
// <local-name> ::= Z <(function) encoding> E <(entity) name> [<discriminator>]
|
|
// ::= Z <(function) encoding> E s [<discriminator>]
|
|
//
|
|
// Parsing a common prefix of these two productions together avoids an
|
|
// exponential blowup of backtracking. Parse like:
|
|
// <local-name> := Z <encoding> E <local-name-suffix>
|
|
// <local-name-suffix> ::= s [<discriminator>]
|
|
// ::= <name> [<discriminator>]
|
|
|
|
static bool ParseLocalNameSuffix(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
|
|
if (MaybeAppend(state, "::") && ParseName(state) &&
|
|
Optional(ParseDiscriminator(state))) {
|
|
return true;
|
|
}
|
|
|
|
// Since we're not going to overwrite the above "::" by re-parsing the
|
|
// <encoding> (whose trailing '\0' byte was in the byte now holding the
|
|
// first ':'), we have to rollback the "::" if the <name> parse failed.
|
|
if (state->parse_state.append) {
|
|
state->out[state->parse_state.out_cur_idx - 2] = '\0';
|
|
}
|
|
|
|
return ParseOneCharToken(state, 's') && Optional(ParseDiscriminator(state));
|
|
}
|
|
|
|
static bool ParseLocalName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'Z') && ParseEncoding(state) &&
|
|
ParseOneCharToken(state, 'E') && ParseLocalNameSuffix(state)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <discriminator> := _ <(non-negative) number>
|
|
static bool ParseDiscriminator(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, '_') && ParseNumber(state, nullptr)) {
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// <substitution> ::= S_
|
|
// ::= S <seq-id> _
|
|
// ::= St, etc.
|
|
//
|
|
// "St" is special in that it's not valid as a standalone name, and it *is*
|
|
// allowed to precede a name without being wrapped in "N...E". This means that
|
|
// if we accept it on its own, we can accept "St1a" and try to parse
|
|
// template-args, then fail and backtrack, accept "St" on its own, then "1a" as
|
|
// an unqualified name and re-parse the same template-args. To block this
|
|
// exponential backtracking, we disable it with 'accept_std=false' in
|
|
// problematic contexts.
|
|
static bool ParseSubstitution(State *state, bool accept_std) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (ParseTwoCharToken(state, "S_")) {
|
|
MaybeAppend(state, "?"); // We don't support substitutions.
|
|
return true;
|
|
}
|
|
|
|
ParseState copy = state->parse_state;
|
|
if (ParseOneCharToken(state, 'S') && ParseSeqId(state) &&
|
|
ParseOneCharToken(state, '_')) {
|
|
MaybeAppend(state, "?"); // We don't support substitutions.
|
|
return true;
|
|
}
|
|
state->parse_state = copy;
|
|
|
|
// Expand abbreviations like "St" => "std".
|
|
if (ParseOneCharToken(state, 'S')) {
|
|
const AbbrevPair *p;
|
|
for (p = kSubstitutionList; p->abbrev != nullptr; ++p) {
|
|
if (RemainingInput(state)[0] == p->abbrev[1] &&
|
|
(accept_std || p->abbrev[1] != 't')) {
|
|
MaybeAppend(state, "std");
|
|
if (p->real_name[0] != '\0') {
|
|
MaybeAppend(state, "::");
|
|
MaybeAppend(state, p->real_name);
|
|
}
|
|
++state->parse_state.mangled_idx;
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
state->parse_state = copy;
|
|
return false;
|
|
}
|
|
|
|
// Parse <mangled-name>, optionally followed by either a function-clone suffix
|
|
// or version suffix. Returns true only if all of "mangled_cur" was consumed.
|
|
static bool ParseTopLevelMangledName(State *state) {
|
|
ComplexityGuard guard(state);
|
|
if (guard.IsTooComplex()) return false;
|
|
if (ParseMangledName(state)) {
|
|
if (RemainingInput(state)[0] != '\0') {
|
|
// Drop trailing function clone suffix, if any.
|
|
if (IsFunctionCloneSuffix(RemainingInput(state))) {
|
|
return true;
|
|
}
|
|
// Append trailing version suffix if any.
|
|
// ex. _Z3foo@@GLIBCXX_3.4
|
|
if (RemainingInput(state)[0] == '@') {
|
|
MaybeAppend(state, RemainingInput(state));
|
|
return true;
|
|
}
|
|
return false; // Unconsumed suffix.
|
|
}
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
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static bool Overflowed(const State *state) {
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return state->parse_state.out_cur_idx >= state->out_end_idx;
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|
}
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|
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// The demangler entry point.
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bool Demangle(const char *mangled, char *out, int out_size) {
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|
State state;
|
|
InitState(&state, mangled, out, out_size);
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|
return ParseTopLevelMangledName(&state) && !Overflowed(&state) &&
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|
state.parse_state.out_cur_idx > 0;
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|
}
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|
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} // namespace debugging_internal
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ABSL_NAMESPACE_END
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} // namespace absl
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