/*

 * Copyright (C) 2007, 2009 Apple Inc. All rights reserved.

 * Copyright (C) 2007 Justin Haygood (jhaygood@reaktix.com)

 *

 * 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 "config.h"

#include "Threading.h"

#if USE(PTHREADS)

#include "CurrentTime.h"

#include "HashMap.h"

#include "MainThread.h"

#include "RandomNumberSeed.h"

#include "StdLibExtras.h"

#include "ThreadIdentifierDataPthreads.h"

#include "ThreadSpecific.h"

#include "UnusedParam.h"

#include <errno.h>

#if !COMPILER(MSVC)

#include <limits.h>

#include <sys/time.h>

#endif

#if OS(ANDROID)

#include "JNIUtility.h"

#endif

namespace WTF {

typedef HashMap<ThreadIdentifier, pthread_t> ThreadMap;

static Mutex* atomicallyInitializedStaticMutex;

void clearPthreadHandleForIdentifier(ThreadIdentifier);

static Mutex& threadMapMutex()

{

    DEFINE_STATIC_LOCAL(Mutex, mutex, ());

    return mutex;

}

void initializeThreading()

{

    if (atomicallyInitializedStaticMutex)

        return;

    atomicallyInitializedStaticMutex = new Mutex;

    threadMapMutex();

    initializeRandomNumberGenerator();

}

void lockAtomicallyInitializedStaticMutex()

{

    ASSERT(atomicallyInitializedStaticMutex);

    atomicallyInitializedStaticMutex->lock();

}

void unlockAtomicallyInitializedStaticMutex()

{

    atomicallyInitializedStaticMutex->unlock();

}

static ThreadMap& threadMap()

{

    DEFINE_STATIC_LOCAL(ThreadMap, map, ());

    return map;

}

static ThreadIdentifier identifierByPthreadHandle(const pthread_t& pthreadHandle)

{

    MutexLocker locker(threadMapMutex());

    ThreadMap::iterator i = threadMap().begin();

    for (; i != threadMap().end(); ++i) {

        if (pthread_equal(i->second, pthreadHandle))

            return i->first;

    }

    return 0;

}

static ThreadIdentifier establishIdentifierForPthreadHandle(const pthread_t& pthreadHandle)

{

    ASSERT(!identifierByPthreadHandle(pthreadHandle));

    MutexLocker locker(threadMapMutex());

    static ThreadIdentifier identifierCount = 1;

    threadMap().add(identifierCount, pthreadHandle);

    return identifierCount++;

}

static pthread_t pthreadHandleForIdentifier(ThreadIdentifier id)

{

    MutexLocker locker(threadMapMutex());

    return threadMap().get(id);

}

void clearPthreadHandleForIdentifier(ThreadIdentifier id)

{

    MutexLocker locker(threadMapMutex());

    ASSERT(threadMap().contains(id));

    threadMap().remove(id);

}

#if OS(ANDROID)

// On the Android platform, threads must be registered with the VM before they run.

struct ThreadData {

    ThreadFunction entryPoint;

    void* arg;

};

static void* runThreadWithRegistration(void* arg)

{

    ThreadData* data = static_cast<ThreadData*>(arg);

    JavaVM* vm = JSC::Bindings::getJavaVM();

    JNIEnv* env;

    void* ret = 0;

    if (vm->AttachCurrentThread(&env, 0) == JNI_OK) {

        ret = data->entryPoint(data->arg);

        vm->DetachCurrentThread();

    }

    delete data;

    return ret;

}

ThreadIdentifier createThreadInternal(ThreadFunction entryPoint, void* data, const char*)

{

    pthread_t threadHandle;

    ThreadData* threadData = new ThreadData();

    threadData->entryPoint = entryPoint;

    threadData->arg = data;

    if (pthread_create(&threadHandle, 0, runThreadWithRegistration, static_cast<void*>(threadData))) {

        LOG_ERROR("Failed to create pthread at entry point %p with data %p", entryPoint, data);

        delete threadData;

        return 0;

    }

    return establishIdentifierForPthreadHandle(threadHandle);

}

#else

ThreadIdentifier createThreadInternal(ThreadFunction entryPoint, void* data, const char*)

{

    pthread_t threadHandle;

    if (pthread_create(&threadHandle, 0, entryPoint, data)) {

        LOG_ERROR("Failed to create pthread at entry point %p with data %p", entryPoint, data);

        return 0;

    }

    return establishIdentifierForPthreadHandle(threadHandle);

}

#endif

void initializeCurrentThreadInternal(const char* threadName)

{

#if HAVE(PTHREAD_SETNAME_NP)

    pthread_setname_np(threadName);

#else

    UNUSED_PARAM(threadName);

#endif

    ThreadIdentifier id = identifierByPthreadHandle(pthread_self());

    ASSERT(id);

    ThreadIdentifierData::initialize(id);

}

int waitForThreadCompletion(ThreadIdentifier threadID, void** result)

{

    ASSERT(threadID);

    pthread_t pthreadHandle = pthreadHandleForIdentifier(threadID);

    if (!pthreadHandle)

        return 0;

    int joinResult = pthread_join(pthreadHandle, result);

    if (joinResult == EDEADLK)

        LOG_ERROR("ThreadIdentifier %u was found to be deadlocked trying to quit", threadID);

    return joinResult;

}

void detachThread(ThreadIdentifier threadID)

{

    ASSERT(threadID);

    pthread_t pthreadHandle = pthreadHandleForIdentifier(threadID);

    if (!pthreadHandle)

        return;

    pthread_detach(pthreadHandle);

}

ThreadIdentifier currentThread()

{

    ThreadIdentifier id = ThreadIdentifierData::identifier();

    if (id)

        return id;

    // Not a WTF-created thread, ThreadIdentifier is not established yet.

    id = establishIdentifierForPthreadHandle(pthread_self());

    ThreadIdentifierData::initialize(id);

    return id;

}

Mutex::Mutex()

{

#if PTHREAD_MUTEX_NORMAL == PTHREAD_MUTEX_DEFAULT

    pthread_mutex_init(&m_mutex, 0);

#else

    pthread_mutexattr_t attr;

    pthread_mutexattr_init(&attr);

    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL);

    pthread_mutex_init(&m_mutex, &attr);

    pthread_mutexattr_destroy(&attr);

#endif

}

Mutex::~Mutex()

{

    pthread_mutex_destroy(&m_mutex);

}

void Mutex::lock()

{

    int result = pthread_mutex_lock(&m_mutex);

    ASSERT_UNUSED(result, !result);

}

bool Mutex::tryLock()

{

    int result = pthread_mutex_trylock(&m_mutex);

    if (result == 0)

        return true;

    if (result == EBUSY)

        return false;

    ASSERT_NOT_REACHED();

    return false;

}

void Mutex::unlock()

{

    int result = pthread_mutex_unlock(&m_mutex);

    ASSERT_UNUSED(result, !result);

}

#if HAVE(PTHREAD_RWLOCK)

ReadWriteLock::ReadWriteLock()

{

    pthread_rwlock_init(&m_readWriteLock, NULL);

}

ReadWriteLock::~ReadWriteLock()

{

    pthread_rwlock_destroy(&m_readWriteLock);

}

void ReadWriteLock::readLock()

{

    int result = pthread_rwlock_rdlock(&m_readWriteLock);

    ASSERT_UNUSED(result, !result);

}

bool ReadWriteLock::tryReadLock()

{

    int result = pthread_rwlock_tryrdlock(&m_readWriteLock);

    if (result == 0)

        return true;

    if (result == EBUSY || result == EAGAIN)

        return false;

    ASSERT_NOT_REACHED();

    return false;

}

void ReadWriteLock::writeLock()

{

    int result = pthread_rwlock_wrlock(&m_readWriteLock);

    ASSERT_UNUSED(result, !result);

}

bool ReadWriteLock::tryWriteLock()

{

    int result = pthread_rwlock_trywrlock(&m_readWriteLock);

    if (result == 0)

        return true;

    if (result == EBUSY || result == EAGAIN)

        return false;

    ASSERT_NOT_REACHED();

    return false;

}

void ReadWriteLock::unlock()

{

    int result = pthread_rwlock_unlock(&m_readWriteLock);

    ASSERT_UNUSED(result, !result);

}

#endif  // HAVE(PTHREAD_RWLOCK)

ThreadCondition::ThreadCondition()

{ 

    pthread_cond_init(&m_condition, NULL);

}

ThreadCondition::~ThreadCondition()

{

    pthread_cond_destroy(&m_condition);

}

void ThreadCondition::wait(Mutex& mutex)

{

    int result = pthread_cond_wait(&m_condition, &mutex.impl());

    ASSERT_UNUSED(result, !result);

}

bool ThreadCondition::timedWait(Mutex& mutex, double absoluteTime)

{

    if (absoluteTime < currentTime())

        return false;

    if (absoluteTime > INT_MAX) {

        wait(mutex);

        return true;

    }

    int timeSeconds = static_cast<int>(absoluteTime);

    int timeNanoseconds = static_cast<int>((absoluteTime - timeSeconds) * 1E9);

    timespec targetTime;

    targetTime.tv_sec = timeSeconds;

    targetTime.tv_nsec = timeNanoseconds;

    return pthread_cond_timedwait(&m_condition, &mutex.impl(), &targetTime) == 0;

}

void ThreadCondition::signal()

{

    int result = pthread_cond_signal(&m_condition);

    ASSERT_UNUSED(result, !result);

}

void ThreadCondition::broadcast()

{

    int result = pthread_cond_broadcast(&m_condition);

    ASSERT_UNUSED(result, !result);

}

} // namespace WTF

#endif // USE(PTHREADS)