thread_pool.cpp

#include "thread_pool.h"
#include <cstdio>

void CTask::setData(void* data) {
    m_ptrData = data;
}

//静态成员初始化
vector<CTask*> CThreadPool::m_vecTaskList;
bool CThreadPool::shutdown = false;
pthread_mutex_t CThreadPool::m_pthreadMutex = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t CThreadPool::m_pthreadCond = PTHREAD_COND_INITIALIZER;

//线程管理类构造函数
CThreadPool::CThreadPool(int threadNum) {
    this->m_iThreadNum = threadNum;
    printf("I will create %d threads.\n", threadNum);
    Create();
}

//线程回调函数
void* CThreadPool::ThreadFunc(void* threadData) {
    pthread_t tid = pthread_self();
    while(1)
    {
        pthread_mutex_lock(&m_pthreadMutex);
        //如果队列为空，等待新任务进入任务队列
        while(m_vecTaskList.size() == 0 && !shutdown)
            pthread_cond_wait(&m_pthreadCond, &m_pthreadMutex);
        
        //关闭线程
        if(shutdown)
        {
            pthread_mutex_unlock(&m_pthreadMutex);
            printf("[tid: %lu]\texit\n", pthread_self());
            pthread_exit(NULL);
        }
        
        printf("[tid: %lu]\trun: ", tid);
        vector<CTask*>::iterator iter = m_vecTaskList.begin();
        //取出一个任务并处理之
        CTask* task = *iter;
        if(iter != m_vecTaskList.end())
        {
            task = *iter;
            m_vecTaskList.erase(iter);
        }
        
        pthread_mutex_unlock(&m_pthreadMutex);
        
        task->Run();    //执行任务
        printf("[tid: %lu]\tidle\n", tid);
        
    }
    
    return (void*)0;
}

//往任务队列里添加任务并发出线程同步信号
int CThreadPool::AddTask(CTask *task) { 
    pthread_mutex_lock(&m_pthreadMutex);    
    m_vecTaskList.push_back(task);  
    pthread_mutex_unlock(&m_pthreadMutex);  
    pthread_cond_signal(&m_pthreadCond);    
    
    return 0;
}

//创建线程
int CThreadPool::Create() { 
    pthread_id = new pthread_t[m_iThreadNum];
        for(int i = 0; i < m_iThreadNum; i++)
            pthread_create(&pthread_id[i], NULL, ThreadFunc, NULL);
        
    return 0;
}

//停止所有线程
int CThreadPool::StopAll() {    
    //避免重复调用
    if(shutdown)
        return -1;
    printf("Now I will end all threads!\n\n");
    
    //唤醒所有等待进程，线程池也要销毁了
    shutdown = true;
    pthread_cond_broadcast(&m_pthreadCond);
    
    //清楚僵尸
    for(int i = 0; i < m_iThreadNum; i++)
        pthread_join(pthread_id[i], NULL);
    
    delete[] pthread_id;
    pthread_id = NULL;
    
    //销毁互斥量和条件变量
    pthread_mutex_destroy(&m_pthreadMutex);
    pthread_cond_destroy(&m_pthreadCond);
    
    return 0;
}

//获取当前队列中的任务数
int CThreadPool::getTaskSize() {    
    return m_vecTaskList.size();
}