third_party/blink/renderer/platform/wtf/threading_pthreads.cc

/*
 * Copyright (C) 2007, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2007 Justin Haygood (jhaygood@reaktix.com)
 * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  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.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") 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 APPLE AND ITS 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 APPLE OR ITS 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.
 */

#include "third_party/blink/renderer/platform/wtf/threading.h"

#include "build/build_config.h"

#if defined(OS_POSIX) || defined(OS_FUCHSIA)

#include <errno.h>
#include <limits.h>
#include <sched.h>
#include <sys/time.h>
#include "base/threading/scoped_blocking_call.h"
#include "third_party/blink/renderer/platform/wtf/date_math.h"
#include "third_party/blink/renderer/platform/wtf/hash_map.h"
#include "third_party/blink/renderer/platform/wtf/std_lib_extras.h"
#include "third_party/blink/renderer/platform/wtf/thread_specific.h"
#include "third_party/blink/renderer/platform/wtf/threading.h"
#include "third_party/blink/renderer/platform/wtf/threading_primitives.h"

#if defined(OS_MAC)
#include <objc/objc-auto.h>
#endif

#if defined(OS_LINUX) || defined(OS_CHROMEOS)
#include <sys/syscall.h>
#endif

#if defined(OS_LINUX) || defined(OS_CHROMEOS) || defined(OS_ANDROID)
#include <unistd.h>
#endif

namespace WTF {

MutexBase::MutexBase(bool recursive) {
  pthread_mutexattr_t attr;
  pthread_mutexattr_init(&attr);
  pthread_mutexattr_settype(
      &attr, recursive ? PTHREAD_MUTEX_RECURSIVE : PTHREAD_MUTEX_NORMAL);

  int result = pthread_mutex_init(&mutex_.internal_mutex_, &attr);
  DCHECK_EQ(result, 0);
#if DCHECK_IS_ON()
  mutex_.recursion_count_ = 0;
#endif

  pthread_mutexattr_destroy(&attr);
}

MutexBase::~MutexBase() {
  int result = pthread_mutex_destroy(&mutex_.internal_mutex_);
  DCHECK_EQ(result, 0);
}

void MutexBase::lock() {
  int result = pthread_mutex_lock(&mutex_.internal_mutex_);
  DCHECK_EQ(result, 0);
#if DCHECK_IS_ON()
  DCHECK(!mutex_.recursion_count_)
      << "WTF does not support recursive mutex acquisition!";
  ++mutex_.recursion_count_;
#endif
}

void MutexBase::unlock() {
#if DCHECK_IS_ON()
  DCHECK(mutex_.recursion_count_);
  --mutex_.recursion_count_;
#endif
  int result = pthread_mutex_unlock(&mutex_.internal_mutex_);
  DCHECK_EQ(result, 0);
}

// There is a separate tryLock implementation for the Mutex and the
// RecursiveMutex since on Windows we need to manually check if tryLock should
// succeed or not for the non-recursive mutex. On Linux the two implementations
// are equal except we can assert the recursion count is always zero for the
// non-recursive mutex.
bool Mutex::TryLock() {
  int result = pthread_mutex_trylock(&mutex_.internal_mutex_);
  if (result == 0) {
#if DCHECK_IS_ON()
    // The Mutex class is not recursive, so the recursionCount should be
    // zero after getting the lock.
    DCHECK(!mutex_.recursion_count_)
        << "WTF does not support recursive mutex acquisition!";
    ++mutex_.recursion_count_;
#endif
    return true;
  }
  if (result == EBUSY)
    return false;

  NOTREACHED();
  return false;
}

bool RecursiveMutex::TryLock() {
  int result = pthread_mutex_trylock(&mutex_.internal_mutex_);
  if (result == 0) {
#if DCHECK_IS_ON()
    DCHECK(!mutex_.recursion_count_)
        << "WTF does not support recursive mutex acquisition!";
    ++mutex_.recursion_count_;
#endif
    return true;
  }
  if (result == EBUSY)
    return false;

  NOTREACHED();
  return false;
}

ThreadCondition::ThreadCondition(Mutex& mutex) : mutex_(mutex.Impl()) {
  pthread_cond_init(&condition_, nullptr);
}

ThreadCondition::~ThreadCondition() {
  pthread_cond_destroy(&condition_);
}

void ThreadCondition::Wait() {
  base::ScopedBlockingCall scoped_blocking_call(FROM_HERE,
                                                base::BlockingType::MAY_BLOCK);
#if DCHECK_IS_ON()
  --mutex_.recursion_count_;
#endif
  int result = pthread_cond_wait(&condition_, &mutex_.internal_mutex_);
  DCHECK_EQ(result, 0);
#if DCHECK_IS_ON()
  ++mutex_.recursion_count_;
#endif
}

void ThreadCondition::Signal() {
  int result = pthread_cond_signal(&condition_);
  DCHECK_EQ(result, 0);
}

void ThreadCondition::Broadcast() {
  int result = pthread_cond_broadcast(&condition_);
  DCHECK_EQ(result, 0);
}

}  // namespace WTF

#endif  // defined(OS_POSIX) || defined(OS_FUCHSIA)