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Diffstat (limited to 'security/sandbox/chromium/base/synchronization/lock.h')
-rw-r--r-- | security/sandbox/chromium/base/synchronization/lock.h | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/security/sandbox/chromium/base/synchronization/lock.h b/security/sandbox/chromium/base/synchronization/lock.h deleted file mode 100644 index f7dd35dcc..000000000 --- a/security/sandbox/chromium/base/synchronization/lock.h +++ /dev/null @@ -1,140 +0,0 @@ -// Copyright (c) 2011 The Chromium Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#ifndef BASE_SYNCHRONIZATION_LOCK_H_ -#define BASE_SYNCHRONIZATION_LOCK_H_ - -#include "base/base_export.h" -#include "base/logging.h" -#include "base/macros.h" -#include "base/synchronization/lock_impl.h" -#include "base/threading/platform_thread.h" -#include "build/build_config.h" - -namespace base { - -// A convenient wrapper for an OS specific critical section. The only real -// intelligence in this class is in debug mode for the support for the -// AssertAcquired() method. -class BASE_EXPORT Lock { - public: -#if !DCHECK_IS_ON() - // Optimized wrapper implementation - Lock() : lock_() {} - ~Lock() {} - void Acquire() { lock_.Lock(); } - void Release() { lock_.Unlock(); } - - // If the lock is not held, take it and return true. If the lock is already - // held by another thread, immediately return false. This must not be called - // by a thread already holding the lock (what happens is undefined and an - // assertion may fail). - bool Try() { return lock_.Try(); } - - // Null implementation if not debug. - void AssertAcquired() const {} -#else - Lock(); - ~Lock(); - - // NOTE: Although windows critical sections support recursive locks, we do not - // allow this, and we will commonly fire a DCHECK() if a thread attempts to - // acquire the lock a second time (while already holding it). - void Acquire() { - lock_.Lock(); - CheckUnheldAndMark(); - } - void Release() { - CheckHeldAndUnmark(); - lock_.Unlock(); - } - - bool Try() { - bool rv = lock_.Try(); - if (rv) { - CheckUnheldAndMark(); - } - return rv; - } - - void AssertAcquired() const; -#endif // DCHECK_IS_ON() - -#if defined(OS_POSIX) - // The posix implementation of ConditionVariable needs to be able - // to see our lock and tweak our debugging counters, as it releases - // and acquires locks inside of pthread_cond_{timed,}wait. - friend class ConditionVariable; -#elif defined(OS_WIN) - // The Windows Vista implementation of ConditionVariable needs the - // native handle of the critical section. - friend class WinVistaCondVar; -#endif - - private: -#if DCHECK_IS_ON() - // Members and routines taking care of locks assertions. - // Note that this checks for recursive locks and allows them - // if the variable is set. This is allowed by the underlying implementation - // on windows but not on Posix, so we're doing unneeded checks on Posix. - // It's worth it to share the code. - void CheckHeldAndUnmark(); - void CheckUnheldAndMark(); - - // All private data is implicitly protected by lock_. - // Be VERY careful to only access members under that lock. - base::PlatformThreadRef owning_thread_ref_; -#endif // DCHECK_IS_ON() - - // Platform specific underlying lock implementation. - internal::LockImpl lock_; - - DISALLOW_COPY_AND_ASSIGN(Lock); -}; - -// A helper class that acquires the given Lock while the AutoLock is in scope. -class AutoLock { - public: - struct AlreadyAcquired {}; - - explicit AutoLock(Lock& lock) : lock_(lock) { - lock_.Acquire(); - } - - AutoLock(Lock& lock, const AlreadyAcquired&) : lock_(lock) { - lock_.AssertAcquired(); - } - - ~AutoLock() { - lock_.AssertAcquired(); - lock_.Release(); - } - - private: - Lock& lock_; - DISALLOW_COPY_AND_ASSIGN(AutoLock); -}; - -// AutoUnlock is a helper that will Release() the |lock| argument in the -// constructor, and re-Acquire() it in the destructor. -class AutoUnlock { - public: - explicit AutoUnlock(Lock& lock) : lock_(lock) { - // We require our caller to have the lock. - lock_.AssertAcquired(); - lock_.Release(); - } - - ~AutoUnlock() { - lock_.Acquire(); - } - - private: - Lock& lock_; - DISALLOW_COPY_AND_ASSIGN(AutoUnlock); -}; - -} // namespace base - -#endif // BASE_SYNCHRONIZATION_LOCK_H_ |