src/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h

   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
  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.
  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.
  57   virtual bool SymbolizeData(uptr addr, DataInfo *info) {
  58     UNIMPLEMENTED();
  59   }
  60
  61   virtual void Flush() {}
  62
  63   // Return nullptr to fallback to the default platform-specific demangler.
  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:
  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.
  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 *FormatAndSendCommand(bool is_data, const char *module_name,
 128                                    uptr module_offset, ModuleArch arch);
 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