池[3]

/*

   2中的CProdcons对象需要作为全局变量被使用，否则起不到“池”的效果，使用不方便，于是这里改为“单件”方式

*/

 

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>

#define BUFFER_SIZE 8
#define GET_POS(x) ((x + 1) % BUFFER_SIZE)



#ifndef _CDATA_H_
#define _cDATA_H_

class CData
{
    public:
        CData(unsigned int size);
        ~CData();

        int *data;
};

CData::CData(unsigned int size)
{
    data = (int *)malloc(sizeof(unsigned int)/sizeof(char) * size);
}

CData::~CData()
{
    if(data)
        delete data;
    data = NULL;
}


#endif


#ifndef _CPRODCONS_H_
#define _CPRODCONS_H_

class CProdcons
{
    public:
        static CProdcons* getInstance();        
        void put(int data);
        int get();

    protected:
        CProdcons();
        ~CProdcons();

    private:
        CData *m_data;
        int nrRead;
        int nrWrite;
                pthread_mutex_t lock;
        pthread_cond_t notempty;
        pthread_cond_t notfull;
};

CProdcons::CProdcons()
{
    m_data = new CData(BUFFER_SIZE);
    nrRead = nrWrite = 0;
　　    pthread_mutex_init(&lock,NULL);
　　    pthread_cond_init(&notempty,NULL);
　　    pthread_cond_init(&notfull,NULL);
}

CProdcons* CProdcons::getInstance()
{
    static CProdcons inst;
    return &inst;
}

CProdcons::~CProdcons()
{
    if(m_data)
    {
        delete m_data;
        m_data = NULL;
    }
    pthread_mutex_destroy(&lock);
　    pthread_cond_destroy(&notempty);
　    pthread_cond_destroy(&notfull);    
}

void CProdcons::put(int data){

　　pthread_mutex_lock(&lock);
 　 if( (GET_POS(nrWrite) == GET_POS(nrRead)) && (nrWrite > nrRead) )
　　{
　　 pthread_cond_wait(&notfull, &lock) ;
　　}
　　m_data->data[GET_POS(nrWrite)]=data;
　　nrWrite++;

　　pthread_cond_signal(&notempty);
　　pthread_mutex_unlock(&lock)
}

int CProdcons::get(){

　　int data;
　　pthread_mutex_lock(&lock);
　　if( (GET_POS(nrWrite) == GET_POS(nrRead)) && (nrWrite == nrRead) )
　　{
　　 pthread_cond_wait(&notempty, &lock);
　　}
　　data = m_data->data[GET_POS(nrRead)];
　　nrRead++;

　　pthread_cond_signal(&notfull);
　　pthread_mutex_unlock(&lock);
　　return data;
}

#endif


调用方式如下：

 

 

 



void *thread_P(void *arg)
{
    CProdcons *cp = CProdcons::getInstance();  
    int i = 1;
    while(1)
        cp->put(i++);
}

void *thread_V(void *arg)
{
    CProdcons *cp = CProdcons::getInstance();
    int i = 1;
    while(1)
        printf("%d\n",cp->get());
}


int main()
{
    int ret = 0;
    pthread_t thread_1;
    pthread_t thread_2;
    ret = pthread_create(&thread_1,NULL,thread_P,NULL);
    if(ret!=0)
        return -1;
    ret = pthread_create(&thread_2,NULL,thread_V,NULL);
    if(ret!=0)
        return -1;
    while(1)
    {    
        sleep(10);
    }
    return 0;
};