Implement a simple demangler.
The purpose of this demangler is to avoid crashes for any string.
- It does one pass and should avoid going past the end of the string.
- The code avoids recursion to minimize the amount of stack required.
- It cannot demangle all mangled names, but it should be able to work
on nearly all names in normal stack traces.
- If the mangled name is too large, it will stop demangling and return
as if the name is not a demangled name.
Test: Passes new unit tests.
Change-Id: I596f74a533c0e093d1517c6bd11cced07009d321
diff --git a/demangle/Demangler.h b/demangle/Demangler.h
new file mode 100644
index 0000000..3bd4f3c
--- /dev/null
+++ b/demangle/Demangler.h
@@ -0,0 +1,191 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LIB_DEMANGLE_DEMANGLER_H
+#define __LIB_DEMANGLE_DEMANGLER_H
+
+#include <assert.h>
+
+#include <stack>
+#include <string>
+#include <vector>
+
+class Demangler {
+ public:
+ Demangler() = default;
+
+ // NOTE: The max_length is not guaranteed to be the absolute max length
+ // of a string that will be rejected. Under certain circumstances the
+ // length check will not occur until after the second letter of a pair
+ // is checked.
+ std::string Parse(const char* name, size_t max_length = kMaxDefaultLength);
+
+ void AppendCurrent(const std::string& str);
+ void AppendCurrent(const char* str);
+ void AppendArgument(const std::string& str);
+ std::string GetArgumentsString();
+ void FinalizeTemplate();
+ const char* ParseS(const char* name);
+ const char* AppendOperatorString(const char* name);
+ void Save(const std::string& str, bool is_name);
+
+ private:
+ void Clear() {
+ parse_funcs_.clear();
+ function_name_.clear();
+ function_suffix_.clear();
+ first_save_.clear();
+ cur_state_.Clear();
+ saves_.clear();
+ while (!state_stack_.empty()) {
+ state_stack_.pop();
+ }
+ last_save_name_ = false;
+ }
+
+ using parse_func_type = const char* (Demangler::*)(const char*);
+ parse_func_type parse_func_;
+ std::vector<parse_func_type> parse_funcs_;
+ std::vector<std::string> saves_;
+ bool last_save_name_;
+
+ std::string function_name_;
+ std::string function_suffix_;
+
+ struct StateData {
+ void Clear() {
+ str.clear();
+ args.clear();
+ prefix.clear();
+ suffixes.clear();
+ last_save.clear();
+ }
+
+ std::string str;
+ std::vector<std::string> args;
+ std::string prefix;
+ std::vector<std::string> suffixes;
+ std::string last_save;
+ };
+ std::stack<StateData> state_stack_;
+ std::string first_save_;
+ StateData cur_state_;
+
+ static const char* GetStringFromLength(const char* name, std::string* str);
+
+ // Parsing functions.
+ const char* ParseComplexString(const char* name);
+ const char* ParseComplexArgument(const char* name);
+ const char* ParseArguments(const char* name);
+ const char* ParseTemplateArguments(const char* name);
+ const char* ParseTemplateArgumentsComplex(const char* name);
+ const char* ParseFunctionArgument(const char* name);
+ const char* ParseFunctionName(const char* name);
+ const char* FindFunctionName(const char* name);
+ const char* Fail(const char*) { return nullptr; }
+
+ // The default maximum string length string to process.
+ static constexpr size_t kMaxDefaultLength = 2048;
+
+ static constexpr const char* kTypes[] = {
+ "signed char", // a
+ "bool", // b
+ "char", // c
+ "double", // d
+ "long double", // e
+ "float", // f
+ "__float128", // g
+ "unsigned char", // h
+ "int", // i
+ "unsigned int", // j
+ nullptr, // k
+ "long", // l
+ "unsigned long", // m
+ "__int128", // n
+ "unsigned __int128", // o
+ nullptr, // p
+ nullptr, // q
+ nullptr, // r
+ "short", // s
+ "unsigned short", // t
+ nullptr, // u
+ "void", // v
+ "wchar_t", // w
+ "long long", // x
+ "unsigned long long", // y
+ "...", // z
+ };
+
+ static constexpr const char* kDTypes[] = {
+ "auto", // a
+ nullptr, // b
+ nullptr, // c
+ "decimal64", // d
+ "decimal128", // e
+ "decimal32", // f
+ nullptr, // g
+ "half", // h
+ "char32_t", // i
+ nullptr, // j
+ nullptr, // k
+ nullptr, // l
+ nullptr, // m
+ "decltype(nullptr)", // n
+ nullptr, // o
+ nullptr, // p
+ nullptr, // q
+ nullptr, // r
+ "char16_t", // s
+ nullptr, // t
+ nullptr, // u
+ nullptr, // v
+ nullptr, // w
+ nullptr, // x
+ nullptr, // y
+ nullptr, // z
+ };
+
+ static constexpr const char* kSTypes[] = {
+ "std::allocator", // a
+ "std::basic_string", // b
+ nullptr, // c
+ "std::iostream", // d
+ nullptr, // e
+ nullptr, // f
+ nullptr, // g
+ nullptr, // h
+ "std::istream", // i
+ nullptr, // j
+ nullptr, // k
+ nullptr, // l
+ nullptr, // m
+ nullptr, // n
+ "std::ostream", // o
+ nullptr, // p
+ nullptr, // q
+ nullptr, // r
+ "std::string", // s
+ nullptr, // t
+ nullptr, // u
+ nullptr, // v
+ nullptr, // w
+ nullptr, // x
+ nullptr, // y
+ nullptr, // z
+ };
+};
+
+#endif // __LIB_DEMANGLE_DEMANGLER_H