Linux pthread 线程池实现

　　基于pthread封装了一个简易的ThreadPool,具有以下特性：

　　1.具有优先级的任务队列

　　2.线程池大小可以二次调整，增加线程或者删除空闲线程

　　3.任务两种重写方式，重写run或者使用函数回调

首先是任务类的声明

class Task{
public:
    string taskName;

public:
    Task(){}
    Task(string _taskName):taskName(_taskName){
        priority=1;
    }
    void setPriority(int pri){
        priority=pri;
    }
    int getPriority(){
        return priority;
    }

    virtual ~Task(){}

    virtual void run()=0;
public:
    int priority;
};
struct TaskCom{
    bool operator()(const Task* t1,const Task* t2){
        return t1->priority<t2->priority;
    }
};
class CbTask:public Task{//回调版本的task
public:
    CbTask(string name,int pri):Task(name){
        setPriority(pri);
    }
    void setCallBack(void *(*_process) (void *_arg), void *_arg){
        process=_process;
        arg=_arg;
    }
    void run(){
         (*process) (arg);
    }
private:
    void*(*process)(void *arg);
    void *arg;
};

class MyTask1:public Task{
public:
    MyTask1(string name,int pri):Task(name){
        setPriority(pri);
    }
    void run(){
        printf("hello,this is MyTask1
");
        sleep(2);
    }
};
MyTask1 *task1=new MyTask1("mytask1",4);

void *printStr(void * str){
    printf("%s
",str);
}
CbTask *task6=new CbTask("mytask6",1);
    char *str="你好";
    task6->setCallBack(printStr,static_cast<void*>(str));
        

线程池声明

class ThreadPool{
private:
    static priority_queue<Task*,vector<Task*>,TaskCom > taskList;//带优先级
    static map<pthread_t,int> threads;
    bool shutdown;
    int maxThreadNum;
    int ThreadNum;

    static pthread_mutex_t mutex;
    static pthread_mutex_t map_mutex;
    static pthread_cond_t cond;

protected:
    static void *threadRoutine(void *arg);
    static void setThreadStat(pthread_t tid,int stat);
public:
    void poolInit();
    void poolDestroy();
    void addThread();
    void delThread(int n);
    void addTask(Task *task);
    int getTaskListSize();
    int getPoolSize();

    ThreadPool(int _threadNum);
    ~ThreadPool();
enum ThreadStat{
    THREAD_RUN=1,
    THREAD_WAIT,
    THREAD_SHUT
};

线程池实现

#include "ThreadPool.h"


priority_queue<Task*,vector<Task*>,TaskCom> ThreadPool::taskList;
map<pthread_t,int> ThreadPool::threads;

pthread_mutex_t ThreadPool::mutex=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t ThreadPool::map_mutex=PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t ThreadPool::cond=PTHREAD_COND_INITIALIZER;

ThreadPool::ThreadPool(int _threadNum):maxThreadNum(_threadNum){
    poolInit();
}
ThreadPool::~ThreadPool(){
    poolDestroy();
}
void *ThreadPool::threadRoutine(void *arg){
    pthread_t tid=pthread_self();
    pthread_mutex_lock(&map_mutex);
    threads.insert(make_pair(tid,THREAD_WAIT));
    int &threadStat=threads[tid];
    pthread_mutex_unlock(&map_mutex);
    while(1){
        pthread_mutex_lock(&mutex);
        while(taskList.size()==0&&threadStat==THREAD_WAIT){
            pthread_cond_wait(&cond,&mutex);
        }
        if(threadStat==THREAD_SHUT){
            pthread_mutex_unlock(&mutex);
            printf("thread %lu will exit
",tid);
            pthread_exit(NULL);
        }
//        printf("task num=%d
",taskList.size());
        Task *task=taskList.top();
        taskList.pop();
//        printf("task num=%d
",taskList.size());
        setThreadStat(tid,THREAD_RUN);
        printf("thread %lu is running with task--> %s*** %d
",tid,task->taskName.c_str(),task->getPriority());
        pthread_mutex_unlock(&mutex);

        task->run();
        setThreadStat(tid,THREAD_WAIT);

        printf("thread %lu has done with task--> %s
",tid,task->taskName.c_str());

    }
    return NULL;
}
void ThreadPool::setThreadStat(pthread_t tid,int stat){
    threads[tid]=stat;
}
void ThreadPool::addThread(){
    pthread_t tid;
    pthread_create(&tid,NULL,threadRoutine,NULL);
    ThreadNum++;
}

void ThreadPool::delThread(int n){
    int num=0;
    int size=getPoolSize();
    if(n>size){
        printf("pool size is less than you input
");
        return;
    }
    while(num<n){
        for(map<pthread_t,int>::iterator ite=threads.begin();ite!=threads.end();){
            if(ite->second==THREAD_WAIT){
                setThreadStat(ite->first,THREAD_SHUT);
//                printf("**thread %lu 
",ite->first);
                pthread_cond_broadcast(&cond);
                pthread_join(ite->first,NULL);
                map<pthread_t,int>::iterator tmp=++ite;
                pthread_mutex_lock(&map_mutex);
                threads.erase(--ite);
                ThreadNum--;
                if(ThreadNum!=threads.size())
                    printf("thread num is wrong
");
                pthread_mutex_unlock(&map_mutex);
                ite=tmp;
//                printf("**thread %lu 
",ite->first);
//                printf("**thread %d
",threads.size());
                num++;
                if(num==n)
                    break;
            }else{
                ++ite;
            }
        }

    }
}
void ThreadPool::poolInit(){
    for(int i=0;i<maxThreadNum;i++)
        addThread();
}
void ThreadPool::poolDestroy(){
    printf("thread pool begin to destory
");
    while(threads.size()!=0){
        for(map<pthread_t,int>::iterator ite=threads.begin();ite!=threads.end();){
            if(ite->second==THREAD_WAIT){
                setThreadStat(ite->first,THREAD_SHUT);
                pthread_cond_broadcast(&cond);
                pthread_join(ite->first,NULL);
                map<pthread_t,int>::iterator tmp=++ite;
                pthread_mutex_lock(&map_mutex);
                threads.erase(--ite);
                ThreadNum--;
                if(ThreadNum!=threads.size())
                    printf("thread num is wrong
");
                pthread_mutex_unlock(&map_mutex);
                ite=tmp;
            }
        }
    }
    pthread_mutex_destroy(&mutex);
    pthread_cond_destroy(&cond);
    printf("thread pool has destoryed
");
}
void ThreadPool::addTask(Task *task){
    taskList.push(task);
    pthread_cond_signal(&cond);
}
int ThreadPool::getTaskListSize(){
    return taskList.size();
}
int ThreadPool::getPoolSize(){
    return ThreadNum;
}

工程

https://github.com/tla001/ThreadPool