asan_lock.h revision c04d8b39795b8faab2c172da59462f4e54823533 
1//===-- asan_lock.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// This file is a part of AddressSanitizer, an address sanity checker.
11//
12// A wrapper for a simple lock.
13//===----------------------------------------------------------------------===//
14#ifndef ASAN_LOCK_H
15#define ASAN_LOCK_H
16
17#include "sanitizer_common/sanitizer_mutex.h"
18#include "asan_internal.h"
19
20// The locks in ASan are global objects and they are never destroyed to avoid
21// at-exit races (that is, a lock is being used by other threads while the main
22// thread is doing atexit destructors).
23// We define the class using opaque storage to avoid including system headers.
24
25namespace __asan {
26
27class AsanLock {
28 public:
29  explicit AsanLock(LinkerInitialized);
30  void Lock();
31  void Unlock();
32  bool IsLocked() { return owner_ != 0; }
33 private:
34  uptr opaque_storage_[10];
35  uptr owner_;  // for debugging and for malloc_introspection_t interface
36};
37
38typedef GenericScopedLock<AsanLock> ScopedLock;
39
40}  // namespace __asan
41
42#endif  // ASAN_LOCK_H
43