1 //===-- sanitizer_symbolizer_internal.h -------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // Header for internal classes and functions to be used by implementations of 11 // symbolizers. 12 // 13 //===----------------------------------------------------------------------===// 14 #ifndef SANITIZER_SYMBOLIZER_INTERNAL_H 15 #define SANITIZER_SYMBOLIZER_INTERNAL_H 16 17 #include "sanitizer_symbolizer.h" 18 19 namespace __sanitizer { 20 21 // Parsing helpers, 'str' is searched for delimiter(s) and a string or uptr 22 // is extracted. When extracting a string, a newly allocated (using 23 // InternalAlloc) and null-terminataed buffer is returned. They return a pointer 24 // to the next characted after the found delimiter. 25 const char *ExtractToken(const char *str, const char *delims, char **result); 26 const char *ExtractInt(const char *str, const char *delims, int *result); 27 const char *ExtractUptr(const char *str, const char *delims, uptr *result); 28 const char *ExtractTokenUpToDelimiter(const char *str, const char *delimiter, 29 char **result); 30 31 const char *DemangleSwiftAndCXX(const char *name); 32 33 // SymbolizerTool is an interface that is implemented by individual "tools" 34 // that can perform symbolication (external llvm-symbolizer, libbacktrace, 35 // Windows DbgHelp symbolizer, etc.). 36 class SymbolizerTool { 37 public: 38 // The main |Symbolizer| class implements a "fallback chain" of symbolizer 39 // tools. In a request to symbolize an address, if one tool returns false, 40 // the next tool in the chain will be tried. 41 SymbolizerTool *next; 42 SymbolizerTool()43 SymbolizerTool() : next(nullptr) { } 44 45 // Can't declare pure virtual functions in sanitizer runtimes: 46 // __cxa_pure_virtual might be unavailable. 47 48 // The |stack| parameter is inout. It is pre-filled with the address, 49 // module base and module offset values and is to be used to construct 50 // other stack frames. SymbolizePC(uptr addr,SymbolizedStack * stack)51 virtual bool SymbolizePC(uptr addr, SymbolizedStack *stack) { 52 UNIMPLEMENTED(); 53 } 54 55 // The |info| parameter is inout. It is pre-filled with the module base 56 // and module offset values. SymbolizeData(uptr addr,DataInfo * info)57 virtual bool SymbolizeData(uptr addr, DataInfo *info) { 58 UNIMPLEMENTED(); 59 } 60 Flush()61 virtual void Flush() {} 62 63 // Return nullptr to fallback to the default platform-specific demangler. Demangle(const char * name)64 virtual const char *Demangle(const char *name) { 65 return nullptr; 66 } 67 }; 68 69 // SymbolizerProcess encapsulates communication between the tool and 70 // external symbolizer program, running in a different subprocess. 71 // SymbolizerProcess may not be used from two threads simultaneously. 72 class SymbolizerProcess { 73 public: 74 explicit SymbolizerProcess(const char *path, bool use_forkpty = false); 75 const char *SendCommand(const char *command); 76 77 protected: ReachedEndOfOutput(const char * buffer,uptr length)78 virtual bool ReachedEndOfOutput(const char *buffer, uptr length) const { 79 UNIMPLEMENTED(); 80 } 81 82 /// The maximum number of arguments required to invoke a tool process. 83 enum { kArgVMax = 6 }; 84 85 /// Fill in an argv array to invoke the child process. GetArgV(const char * path_to_binary,const char * (& argv)[kArgVMax])86 virtual void GetArgV(const char *path_to_binary, 87 const char *(&argv)[kArgVMax]) const { 88 UNIMPLEMENTED(); 89 } 90 91 virtual bool ReadFromSymbolizer(char *buffer, uptr max_length); 92 93 private: 94 bool Restart(); 95 const char *SendCommandImpl(const char *command); 96 bool WriteToSymbolizer(const char *buffer, uptr length); 97 bool StartSymbolizerSubprocess(); 98 99 const char *path_; 100 fd_t input_fd_; 101 fd_t output_fd_; 102 103 static const uptr kBufferSize = 16 * 1024; 104 char buffer_[kBufferSize]; 105 106 static const uptr kMaxTimesRestarted = 5; 107 static const int kSymbolizerStartupTimeMillis = 10; 108 uptr times_restarted_; 109 bool failed_to_start_; 110 bool reported_invalid_path_; 111 bool use_forkpty_; 112 }; 113 114 class LLVMSymbolizerProcess; 115 116 // This tool invokes llvm-symbolizer in a subprocess. It should be as portable 117 // as the llvm-symbolizer tool is. 118 class LLVMSymbolizer : public SymbolizerTool { 119 public: 120 explicit LLVMSymbolizer(const char *path, LowLevelAllocator *allocator); 121 122 bool SymbolizePC(uptr addr, SymbolizedStack *stack) override; 123 124 bool SymbolizeData(uptr addr, DataInfo *info) override; 125 126 private: 127 const char *SendCommand(bool is_data, const char *module_name, 128 uptr module_offset); 129 130 LLVMSymbolizerProcess *symbolizer_process_; 131 static const uptr kBufferSize = 16 * 1024; 132 char buffer_[kBufferSize]; 133 }; 134 135 // Parses one or more two-line strings in the following format: 136 // <function_name> 137 // <file_name>:<line_number>[:<column_number>] 138 // Used by LLVMSymbolizer, Addr2LinePool and InternalSymbolizer, since all of 139 // them use the same output format. Returns true if any useful debug 140 // information was found. 141 void ParseSymbolizePCOutput(const char *str, SymbolizedStack *res); 142 143 // Parses a two-line string in the following format: 144 // <symbol_name> 145 // <start_address> <size> 146 // Used by LLVMSymbolizer and InternalSymbolizer. 147 void ParseSymbolizeDataOutput(const char *str, DataInfo *info); 148 149 } // namespace __sanitizer 150 151 #endif // SANITIZER_SYMBOLIZER_INTERNAL_H 152