music-brainz-go/pthread/example2.c

#include "example2.h"

void * produce(void *buf)
{
    buffer *buff;
    buff = (buffer *)buf;
    printf("\nproducer started");

    for (int i=0;i<20;i++)
    {
        sem_wait(&buff->full);
        pthread_mutex_lock(&buff->mutex);
        
        buff->data[buff->pos] = 0;
        buff->pos = buff->pos + 1;
        printf("\nproduced");

        sem_post(&buff->empty);
        pthread_mutex_unlock(&buff->mutex);

        sleep(1);
    }

    pthread_exit(0);
}

void * consume(void *buf)
{

    buffer * buff;
    buff = (buffer *)buf;
    printf("\nconsumer started");
    for (int i=0;i<20;i++)
    {
        sem_wait(&buff->empty);
        pthread_mutex_lock(&buff->mutex);

        buff->pos = buff->pos - 1;
        printf("\ngot value %d", buff->data[buff->pos]);
        
        printf("\nconsumed");

        sem_post(&buff->full);
        
        pthread_mutex_unlock(&buff->mutex);
        sleep(2);
    }
    pthread_exit(0);
}

void init_buffer(buffer *buf)
{

    sem_init(&buf->empty, 0, 0);
    sem_init(&buf->full, 0, BUFFER_SIZE);
    pthread_mutex_init(&buf->mutex, NULL);
    buf->pos = 0;

    for (int i=0; i<BUFFER_SIZE;i++){
        buf->data[i] = -1;
    }
}