aboutsummaryrefslogtreecommitdiff
path: root/lib/sanitizer_common/sanitizer_symbolizer.h
blob: 3ccfce9995be1c1453e66ef5f9f288bc944bc7d1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
//===-- sanitizer_symbolizer.h ----------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Symbolizer is used by sanitizers to map instruction address to a location in
// source code at run-time. Symbolizer either uses __sanitizer_symbolize_*
// defined in the program, or (if they are missing) tries to find and
// launch "llvm-symbolizer" commandline tool in a separate process and
// communicate with it.
//
// Generally we should try to avoid calling system library functions during
// symbolization (and use their replacements from sanitizer_libc.h instead).
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_SYMBOLIZER_H
#define SANITIZER_SYMBOLIZER_H

#include "sanitizer_common.h"
#include "sanitizer_mutex.h"

namespace __sanitizer {

struct AddressInfo {
  // Owns all the string members. Storage for them is
  // (de)allocated using sanitizer internal allocator.
  uptr address;

  char *module;
  uptr module_offset;

  static const uptr kUnknown = ~(uptr)0;
  char *function;
  uptr function_offset;

  char *file;
  int line;
  int column;

  AddressInfo();
  // Deletes all strings and resets all fields.
  void Clear();
  void FillAddressAndModuleInfo(uptr addr, const char *mod_name,
                                uptr mod_offset);
};

// Linked list of symbolized frames (each frame is described by AddressInfo).
struct SymbolizedStack {
  SymbolizedStack *next;
  AddressInfo info;
  static SymbolizedStack *New(uptr addr);
  // Deletes current, and all subsequent frames in the linked list.
  // The object cannot be accessed after the call to this function.
  void ClearAll();

 private:
  SymbolizedStack();
};

// For now, DataInfo is used to describe global variable.
struct DataInfo {
  // Owns all the string members. Storage for them is
  // (de)allocated using sanitizer internal allocator.
  char *module;
  uptr module_offset;
  char *name;
  uptr start;
  uptr size;

  DataInfo();
  void Clear();
};

class Symbolizer {
 public:
  /// Initialize and return platform-specific implementation of symbolizer
  /// (if it wasn't already initialized).
  static Symbolizer *GetOrInit();
  // Returns a list of symbolized frames for a given address (containing
  // all inlined functions, if necessary).
  virtual SymbolizedStack *SymbolizePC(uptr address) {
    return SymbolizedStack::New(address);
  }
  virtual bool SymbolizeData(uptr address, DataInfo *info) {
    return false;
  }
  virtual bool GetModuleNameAndOffsetForPC(uptr pc, const char **module_name,
                                           uptr *module_address) {
    return false;
  }
  virtual bool CanReturnFileLineInfo() {
    return false;
  }
  // Release internal caches (if any).
  virtual void Flush() {}
  // Attempts to demangle the provided C++ mangled name.
  virtual const char *Demangle(const char *name) {
    return name;
  }
  virtual void PrepareForSandboxing() {}

  // Allow user to install hooks that would be called before/after Symbolizer
  // does the actual file/line info fetching. Specific sanitizers may need this
  // to distinguish system library calls made in user code from calls made
  // during in-process symbolization.
  typedef void (*StartSymbolizationHook)();
  typedef void (*EndSymbolizationHook)();
  // May be called at most once.
  void AddHooks(StartSymbolizationHook start_hook,
                EndSymbolizationHook end_hook);

 private:
  /// Platform-specific function for creating a Symbolizer object.
  static Symbolizer *PlatformInit();
  /// Initialize the symbolizer in a disabled state.  Not thread safe.
  static Symbolizer *Disable();

  static Symbolizer *symbolizer_;
  static StaticSpinMutex init_mu_;

 protected:
  Symbolizer();

  static LowLevelAllocator symbolizer_allocator_;

  StartSymbolizationHook start_hook_;
  EndSymbolizationHook end_hook_;
  class SymbolizerScope {
   public:
    explicit SymbolizerScope(const Symbolizer *sym);
    ~SymbolizerScope();
   private:
    const Symbolizer *sym_;
  };
};

}  // namespace __sanitizer

#endif  // SANITIZER_SYMBOLIZER_H