sanitizer_libignore.h revision 4af0f21c0c98950df1136dbec8824a029ed5bb8e 
1//===-- sanitizer_libignore.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// LibIgnore allows to ignore all interceptors called from a particular set
11// of dynamic libraries. LibIgnore remembers all "called_from_lib" suppressions
12// from the provided SuppressionContext; finds code ranges for the libraries;
13// and checks whether the provided PC value belongs to the code ranges.
14//
15//===----------------------------------------------------------------------===//
16
17#ifndef SANITIZER_LIBIGNORE_H
18#define SANITIZER_LIBIGNORE_H
19
20#include "sanitizer_internal_defs.h"
21#include "sanitizer_common.h"
22#include "sanitizer_suppressions.h"
23#include "sanitizer_atomic.h"
24#include "sanitizer_mutex.h"
25
26namespace __sanitizer {
27
28class LibIgnore {
29 public:
30  explicit LibIgnore(LinkerInitialized);
31
32  // Fetches all "called_from_lib" suppressions from the SuppressionContext.
33  void Init(const SuppressionContext &supp);
34
35  // Must be called after a new dynamic library is loaded.
36  void OnLibraryLoaded();
37
38  // Must be called after a dynamic library is unloaded.
39  void OnLibraryUnloaded();
40
41  // Checks whether the provided PC belongs to one of the ignored libraries.
42  bool IsIgnored(uptr pc) const;
43
44 private:
45  struct Lib {
46    char *templ;
47    char *name;
48    bool loaded;
49  };
50
51  struct LibCodeRange {
52    uptr begin;
53    uptr end;
54  };
55
56  static const uptr kMaxLibs = 128;
57
58  // Hot part:
59  atomic_uintptr_t loaded_count_;
60  LibCodeRange code_ranges_[kMaxLibs];
61
62  // Cold part:
63  BlockingMutex mutex_;
64  uptr count_;
65  Lib libs_[kMaxLibs];
66
67  // Disallow copying of LibIgnore objects.
68  LibIgnore(const LibIgnore&);  // not implemented
69  void operator = (const LibIgnore&);  // not implemented
70};
71
72inline bool LibIgnore::IsIgnored(uptr pc) const {
73  const uptr n = atomic_load(&loaded_count_, memory_order_acquire);
74  for (uptr i = 0; i < n; i++) {
75    if (pc >= code_ranges_[i].begin && pc < code_ranges_[i].end)
76      return true;
77  }
78  return false;
79}
80
81}  // namespace __sanitizer
82
83#endif  // SANITIZER_LIBIGNORE_H
84