Multicore Programming – Producer Consumer problem solved by threads (C++)
#include <iostream> #include <stdlib.h> #include <pthread.h> #include <semaphore.h> using namespace std; pthread_mutex_t status; sem_t empty,full; int buffer[50],x,item; void initialization() { sem_init(&empty,1,0); sem_init(&full,1,50); pthread_mutex_init(&status,NULL); x=0; } void* producer(void *para) { item=rand()%100; sem_wait(&full); //Producer waits if buffer is full pthread_mutex_lock(&status); //Lock the status, so that only one thread can access buffer at a time buffer[x]=item; //producer enters the no. in the buffer cout<<"\nProducer has producer : "<<buffer[x]; x++; pthread_mutex_unlock(&status); //Unlocks the buffer sem_post(&empty); } void* consumer(void *para) { sem_wait(&empty);//if buffer is empty,consumer waits pthread_mutex_lock(&status);//Lock the status, so that only one thread can access buffer at a time x--; item=buffer[x];//Consumer consumes an element cout<<"\nConsumer has consumed : "<<buffer[x]; pthread_mutex_unlock(&status);//Unlocks the buffer sem_post(&full); } int main() { int n,i,p,c; initialization(); cout<<"\nEnter how many producers do you want to create : "; cin>>p; cout<<"\nEnter how many consumers do you want to create : "; cin>>c; pthread_t pid[p],cid; for(i=0;i<p;i++) { pthread_create(&pid[i],NULL,producer,NULL); } for(i=0;i<c;i++) { pthread_create(&cid[i],NULL,consumer,NULL); } for(i=0;i<p;i++) { pthread_join(pid[i],NULL); } for(i=0;i<c;i++) { pthread_join(cid[i],NULL); } return 0; }