/*生产者、消费者*/
#include<stdio.h>
#include<pthread.h>
#define BUFFER_SIZE 16
/***struct prodcons***/
struct prodcons
{
int buffer[BUFFER_SIZE];
pthread_mutex_t lock;
int readpos,writepos;
pthread_cond_t notempty;
pthread_cond_t notfull;
};
void init(struct prodcons *b)
{
pthread_mutex_init(&b->lock,NULL);
pthread_cond_init(&b->notempty,NULL);
pthread_cond_init(&b->notfull,NULL);
b->readpos = 0;
b->writepos = 0;
}
void put(struct prodcons *b,int data)
{
pthread_mutex_lock(&b->lock);
if((b->writepos+1)%BUFFER_SIZE == b->readpos)
{
pthread_cond_wait(&b->notfull,&b->lock);
}
b->buffer[b->writepos] = data;
b->writepos++;
if(b->writepos >=BUFFER_SIZE)
b->writepos = 0;
pthread_cond_signal(&b->notempty);
pthread_mutex_unlock(&b->lock);
}
int get(struct prodcons *b)
{
int data;
pthread_mutex_lock(&b->lock);
if(b->writepos == b->readpos)
{
pthread_cond_wait(&b->notempty,&b->lock);
}
data = b->buffer[b->readpos];
b->readpos++;
if(b->readpos >=BUFFER_SIZE)
b->readpos = 0;
pthread_cond_signal(&b->notfull);
pthread_mutex_unlock(&b->lock);
return data;
}
/***test***/
#define OVER (-1)
struct prodcons buffer;
void *producer(void *data)
{
int n;
for(n = 0;n<10000;n++)
{
printf("%d--->
",n);
put(&buffer,n);
}
put(&buffer,OVER);
return NULL;
}
void *consumer(void *data)
{
int d;
while(1)
{
d = get(&buffer);
if(d == OVER)
break;
printf("--->%d
",d);
}
return NULL;
}
int main(void)
{
pthread_t th_a,th_b;
void *retval;
init(&buffer);
pthread_create(&th_a,NULL,producer,0);
pthread_create(&th_b,NULL,consumer,0);
pthread_join(th_a,&retval);
pthread_join(th_b,&retval);
return 0;
}