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1//===-- sanitizer_symbolizer_internal.h -------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// Header for internal classes and functions to be used by implementations of10// symbolizers.11//12//===----------------------------------------------------------------------===//13#ifndef SANITIZER_SYMBOLIZER_INTERNAL_H14#define SANITIZER_SYMBOLIZER_INTERNAL_H15 16#include "sanitizer_file.h"17#include "sanitizer_symbolizer.h"18#include "sanitizer_vector.h"19 20namespace __sanitizer {21 22// Parsing helpers, 'str' is searched for delimiter(s) and a string or uptr23// is extracted. When extracting a string, a newly allocated (using24// InternalAlloc) and null-terminated buffer is returned. They return a pointer25// to the next characted after the found delimiter.26const char *ExtractToken(const char *str, const char *delims, char **result);27const char *ExtractInt(const char *str, const char *delims, int *result);28const char *ExtractUptr(const char *str, const char *delims, uptr *result);29const char *ExtractTokenUpToDelimiter(const char *str, const char *delimiter,30 char **result);31 32const char *DemangleSwiftAndCXX(const char *name);33 34// SymbolizerTool is an interface that is implemented by individual "tools"35// that can perform symbolication (external llvm-symbolizer, libbacktrace,36// Windows DbgHelp symbolizer, etc.).37class SymbolizerTool {38 public:39 // The main |Symbolizer| class implements a "fallback chain" of symbolizer40 // tools. In a request to symbolize an address, if one tool returns false,41 // the next tool in the chain will be tried.42 SymbolizerTool *next;43 44 SymbolizerTool() : next(nullptr) { }45 46 // Can't declare pure virtual functions in sanitizer runtimes:47 // __cxa_pure_virtual might be unavailable.48 49 // The |stack| parameter is inout. It is pre-filled with the address,50 // module base and module offset values and is to be used to construct51 // other stack frames.52 virtual bool SymbolizePC(uptr addr, SymbolizedStack *stack) {53 UNIMPLEMENTED();54 }55 56 // The |info| parameter is inout. It is pre-filled with the module base57 // and module offset values.58 virtual bool SymbolizeData(uptr addr, DataInfo *info) {59 UNIMPLEMENTED();60 }61 62 virtual bool SymbolizeFrame(uptr addr, FrameInfo *info) {63 return false;64 }65 66 virtual void Flush() {}67 68 // Return nullptr to fallback to the default platform-specific demangler.69 virtual const char *Demangle(const char *name) {70 return nullptr;71 }72 73 protected:74 ~SymbolizerTool() {}75};76 77// SymbolizerProcess encapsulates communication between the tool and78// external symbolizer program, running in a different subprocess.79// SymbolizerProcess may not be used from two threads simultaneously.80class SymbolizerProcess {81 public:82 explicit SymbolizerProcess(const char *path, bool use_posix_spawn = false);83 const char *SendCommand(const char *command);84 85 protected:86 ~SymbolizerProcess() {}87 88 /// The maximum number of arguments required to invoke a tool process.89 static const unsigned kArgVMax = 16;90 91 // Customizable by subclasses.92 virtual bool StartSymbolizerSubprocess();93 virtual bool ReadFromSymbolizer();94 // Return the environment to run the symbolizer in.95 virtual char **GetEnvP() { return GetEnviron(); }96 InternalMmapVector<char> &GetBuff() { return buffer_; }97 98 private:99 virtual bool ReachedEndOfOutput(const char *buffer, uptr length) const {100 UNIMPLEMENTED();101 }102 103 /// Fill in an argv array to invoke the child process.104 virtual void GetArgV(const char *path_to_binary,105 const char *(&argv)[kArgVMax]) const {106 UNIMPLEMENTED();107 }108 109 bool Restart();110 const char *SendCommandImpl(const char *command);111 bool WriteToSymbolizer(const char *buffer, uptr length);112 113 const char *path_;114 fd_t input_fd_;115 fd_t output_fd_;116 117 InternalMmapVector<char> buffer_;118 119 static const uptr kMaxTimesRestarted = 5;120 static const int kSymbolizerStartupTimeMillis = 10;121 uptr times_restarted_;122 bool failed_to_start_;123 bool reported_invalid_path_;124 bool use_posix_spawn_;125};126 127class LLVMSymbolizerProcess;128 129// This tool invokes llvm-symbolizer in a subprocess. It should be as portable130// as the llvm-symbolizer tool is.131class LLVMSymbolizer final : public SymbolizerTool {132 public:133 explicit LLVMSymbolizer(const char *path, LowLevelAllocator *allocator);134 135 bool SymbolizePC(uptr addr, SymbolizedStack *stack) override;136 bool SymbolizeData(uptr addr, DataInfo *info) override;137 bool SymbolizeFrame(uptr addr, FrameInfo *info) override;138 139 private:140 const char *FormatAndSendCommand(const char *command_prefix,141 const char *module_name, uptr module_offset,142 ModuleArch arch);143 144 LLVMSymbolizerProcess *symbolizer_process_;145 static const uptr kBufferSize = 16 * 1024;146 char buffer_[kBufferSize];147};148 149// Parses one or more two-line strings in the following format:150// <function_name>151// <file_name>:<line_number>[:<column_number>]152// Used by LLVMSymbolizer, Addr2LinePool and InternalSymbolizer, since all of153// them use the same output format. Returns true if any useful debug154// information was found.155void ParseSymbolizePCOutput(const char *str, SymbolizedStack *res);156 157// Parses a two-line string in the following format:158// <symbol_name>159// <start_address> <size>160// Used by LLVMSymbolizer and InternalSymbolizer.161void ParseSymbolizeDataOutput(const char *str, DataInfo *info);162 163// Parses repeated strings in the following format:164// <function_name>165// <var_name>166// <file_name>:<line_number>[:<column_number>]167// [<frame_offset>|??] [<size>|??] [<tag_offset>|??]168// Used by LLVMSymbolizer and InternalSymbolizer.169void ParseSymbolizeFrameOutput(const char *str,170 InternalMmapVector<LocalInfo> *locals);171 172} // namespace __sanitizer173 174#endif // SANITIZER_SYMBOLIZER_INTERNAL_H175