c++实现线程池

互斥锁

#ifndef LOCKER_H
#define LOCKER_H

#include <exception>
#include <pthread.h>
#include <semaphore.h>

// 线程同步机制封装类

// 互斥锁类
class locker {
public:
    locker() {
        if(pthread_mutex_init(&m_mutex, NULL) != 0) {
            throw std::exception();
        }
    }

    ~locker() {
        pthread_mutex_destroy(&m_mutex);
    }

    bool lock() {
        return pthread_mutex_lock(&m_mutex) == 0;
    }

    bool unlock() {
        return pthread_mutex_unlock(&m_mutex) == 0;
    }

    pthread_mutex_t *get()
    {
        return &m_mutex;
    }

private:
    pthread_mutex_t m_mutex;
};


// 条件变量类
class cond {
public:
    cond(){
        if (pthread_cond_init(&m_cond, NULL) != 0) {
            throw std::exception();
        }
    }
    ~cond() {
        pthread_cond_destroy(&m_cond);
    }

    bool wait(pthread_mutex_t *m_mutex) {
        int ret = 0;
        ret = pthread_cond_wait(&m_cond, m_mutex);
        return ret == 0;
    }
    bool timewait(pthread_mutex_t *m_mutex, struct timespec t) {
        int ret = 0;
        ret = pthread_cond_timedwait(&m_cond, m_mutex, &t);
        return ret == 0;
    }
    bool signal() {
        return pthread_cond_signal(&m_cond) == 0;
    }
    bool broadcast() {
        return pthread_cond_broadcast(&m_cond) == 0;
    }

private:
    pthread_cond_t m_cond;
};


// 信号量类
class sem {
public:
    sem() {
        if( sem_init( &m_sem, 0, 0 ) != 0 ) {
            throw std::exception();
        }
    }
    sem(int num) {
        if( sem_init( &m_sem, 0, num ) != 0 ) {
            throw std::exception();
        }
    }
    ~sem() {
        sem_destroy( &m_sem );
    }
    // 等待信号量
    bool wait() {
        return sem_wait( &m_sem ) == 0;
    }
    // 增加信号量
    bool post() {
        return sem_post( &m_sem ) == 0;
    }
private:
    sem_t m_sem;
};

#endif

线程池

#ifndef THREADPOOL_H
#define THREADPOOL_H

#include <list>
#include <cstdio>
#include <exception>
#include <pthread.h>
#include "locker.h"

template<typename T>
class threadpool{
public:
    threadpool(int thread_number =8, int max_requests = 10000);
    ~threadpool();
    bool append(T* request);
private:
    static void* worker(void* arg);
    void run();
private:
    int m_thread_number;
    pthread_t* m_threads;
    int m_max_requests;
    std::list<T*>m_workqueue;
    locker m_queuelocker;
    sem m_queuestat;

    bool m_stop;
};
template<typename T>
threadpool< T >::threadpool(int threadnumber,int max_requests):
    m_thread_number(threadnumber),m_max_requests(max_requests),
    m_stop(false),m_threads(NULL){
        
    if((threadnumber<=0||(max_requests<0))){
        throw std::exception();
    }
    m_threads = new pthread_t[m_thread_number];
    if(!m_threads){
        throw std::exception();
    }
    for(int i=0;i<m_thread_number;i++){
        printf( "create the %dth thread\n", i);
        if(pthread_create(m_threads + i, NULL, worker, this ) != 0) {
            delete [] m_threads;
            throw std::exception();
        }
        
        if( pthread_detach( m_threads[i] ) ) {
            delete [] m_threads;
            throw std::exception();
        }
    }

}
template< typename T >
threadpool< T >::~threadpool() {
    delete [] m_threads;
    m_stop = true;
}

template< typename T >
bool threadpool< T >::append( T* request )
{
    // 操作工作队列时一定要加锁，因为它被所有线程共享。
    m_queuelocker.lock();
    if ( m_workqueue.size() > m_max_requests ) {
        m_queuelocker.unlock();
        return false;
    }
    m_workqueue.push_back(request);
    m_queuelocker.unlock();
    m_queuestat.post();
    return true;
}
template< typename T >
void* threadpool< T >::worker( void* arg )
{
    threadpool* pool = ( threadpool* )arg;
    pool->run();
    return pool;
}

template< typename T >
void threadpool< T >::run() {

    while (!m_stop) {
        m_queuestat.wait();
        m_queuelocker.lock();
        if ( m_workqueue.empty() ) {
            m_queuelocker.unlock();
            continue;
        }
        T* request = m_workqueue.front();
        m_workqueue.pop_front();
        m_queuelocker.unlock();
        if ( !request ) {
            continue;
        }
        request->process();
    }

}

#endif