libsanitizer/asan/asan_lock.h

   1 //===-- asan_lock.h ---------------------------------------------*- C++ -*-===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of AddressSanitizer, an address sanity checker.
   9 //
  10 // A wrapper for a simple lock.
  11 //===----------------------------------------------------------------------===//
  12 #ifndef ASAN_LOCK_H
  13 #define ASAN_LOCK_H
  14
  15 #include "sanitizer_common/sanitizer_mutex.h"
  16 #include "asan_internal.h"
  17
  18 // The locks in ASan are global objects and they are never destroyed to avoid
  19 // at-exit races (that is, a lock is being used by other threads while the main
  20 // thread is doing atexit destructors).
  21 // We define the class using opaque storage to avoid including system headers.
  22
  23 namespace __asan {
  24
  25 class AsanLock {
  26  public:
  27   explicit AsanLock(LinkerInitialized);
  28   void Lock();
  29   void Unlock();
  30   bool IsLocked() { return owner_ != 0; }
  31  private:
  32   uptr opaque_storage_[10];
  33   uptr owner_;  // for debugging and for malloc_introspection_t interface
  34 };
  35
  36 typedef GenericScopedLock<AsanLock> ScopedLock;
  37
  38 }  // namespace __asan
  39
  40 #endif  // ASAN_LOCK_H