#include <iostream>
#include <cstdlib>
#include <unistd.h>
#include <pthread.h>
#include <semaphore.h>
using namespace std;
struct{
pthread_rwlock_t rwlock;
int product;
}sharedData = {PTHREAD_RWLOCK_INITIALIZER, 0};
sem_t bin_sem1;
sem_t bin_sem2;
sem_t bin_sem3;
void * produce(void *ptr)
{
for (int i = 0; i < 20; ++i)
{
pthread_rwlock_wrlock(&sharedData.rwlock);
sharedData.product = i;
pthread_rwlock_unlock(&sharedData.rwlock);
sem_post(&bin_sem1);
sem_post(&bin_sem2);
sem_post(&bin_sem3);
sleep(1);
}
}
void * consume1(void *ptr)
{
while(1)
{
sem_wait(&bin_sem1);
pthread_rwlock_rdlock(&sharedData.rwlock);
cout<<"consume1:"<<sharedData.product<<endl;
pthread_rwlock_unlock(&sharedData.rwlock);
}
}
void * consume2(void *ptr)
{
while(1)
{
sem_wait(&bin_sem2);
pthread_rwlock_rdlock(&sharedData.rwlock);
cout<<"consume2:"<<sharedData.product<<endl;
pthread_rwlock_unlock(&sharedData.rwlock);
}
}
void * consume3(void *ptr)
{
while(1)
{
sem_wait(&bin_sem3);
pthread_rwlock_rdlock(&sharedData.rwlock);
cout<<"consume3:"<<sharedData.product<<endl;
pthread_rwlock_unlock(&sharedData.rwlock);
}
}
int main()
{
pthread_t tid1, tid2, tid3,tid4;
sem_init(&bin_sem1,0,5);
sem_init(&bin_sem2,0,5);
sem_init(&bin_sem3,0,5);
pthread_create(&tid1, NULL, produce, NULL);
pthread_create(&tid2, NULL, consume1, NULL);
pthread_create(&tid3, NULL, consume2, NULL);
pthread_create(&tid4, NULL, consume3, NULL);
void *retVal;
pthread_join(tid1, &retVal);
pthread_join(tid2, &retVal);
pthread_join(tid3, &retVal);
pthread_join(tid4, &retVal);
sem_destroy(&bin_sem1);
sem_destroy(&bin_sem2);
sem_destroy(&bin_sem3);
return 0;
}