cef/include/base/cef_lock.h

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Introduce the use of Chromium types (issue #1336). Changes to the CEF public API: - Add base::Bind, base::Callback, base::Lock, base::WeakPtr, scoped_refptr, scoped_ptr and supporting types. - Add include/wrapper/cef_closure_task.h helpers for converting a base::Closure to a CefTask. - Change CefRefPtr to extend scoped_refptr. -- Change CefBase method signatures to match RefCountedThreadSafeBase. - Change IMPLEMENT_REFCOUNTING to use base::AtomicRefCount*. -- Remove the CefAtomic* functions. -- IMPLEMENT_REFCOUNTING now enforces via a compile-time error that the correct class name was passed to the macro. - Change IMPLEMENT_LOCKING to use base::Lock. -- Remove the CefCriticalSection class. -- Deprecate the IMPLEMENT_LOCKING macro. -- base::Lock will DCHECK() in Debug builds if lock usage is reentrant. - Move include/internal/cef_tuple.h to include/base/cef_tuple.h. - Allow an empty |callback| parameter passed to CefBeginTracing. Changes to the CEF implementation: - Fix incorrect names passed to the IMPLEMENT_REFCOUNTING macro. - Fix instances of reentrant locking in the CefXmlObject and CefRequest implementations. - Remove use of the IMPLEMENT_LOCKING macro. Changes to cef_unittests: - Add tests/unittests/chromium_includes.h and always include it first from unit test .cc files to avoid name conflicts with Chromium types. - Fix wrong header include ordering. - Remove use of the IMPLEMENT_LOCKING macro. Changes to cefclient and cefsimple: - Use base::Bind and cef_closure_task.h instead of NewCefRunnable*. - Remove use of the IMPEMENT_LOCKING macro. - Fix incorrect/unnecessary locking. - Add additional runtime thread checks. - Windows: Perform actions on the UI thread instead of the main thread when running in multi-threaded-message-loop mode to avoid excessive locking. git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@1769 5089003a-bbd8-11dd-ad1f-f1f9622dbc98
2014-07-15 00:18:51 +02:00
// Copyright (c) 2014 Marshall A. Greenblatt. Portions copyright (c) 2011
// Google Inc. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the name Chromium Embedded
// Framework nor the names of its contributors may be used to endorse
// or promote products derived from this software without specific prior
// written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef CEF_INCLUDE_BASE_CEF_LOCK_H_
#define CEF_INCLUDE_BASE_CEF_LOCK_H_
#pragma once
#if defined(BASE_SYNCHRONIZATION_LOCK_H_)
// Do nothing if the Chromium header has already been included.
// This can happen in cases where Chromium code is used directly by the
// client application. When using Chromium code directly always include
// the Chromium header first to avoid type conflicts.
#elif defined(BUILDING_CEF_SHARED)
// When building CEF include the Chromium header directly.
#include "base/synchronization/lock.h"
#else // !BUILDING_CEF_SHARED
// The following is substantially similar to the Chromium implementation.
// If the Chromium implementation diverges the below implementation should be
// updated to match.
#include "include/base/cef_macros.h"
#include "include/base/cef_platform_thread.h"
#include "include/base/internal/cef_lock_impl.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 Lock {
public:
#if defined(NDEBUG) // 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 // NDEBUG
private:
#if !defined(NDEBUG)
// 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 // NDEBUG
// 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 // !BUILDING_CEF_SHARED
#endif // CEF_INCLUDE_BASE_CEF_LOCK_H_