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Queue.c
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Queue.c
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#include "queue.h"
Queue create_queue() {
Queue queue = (Queue) malloc(sizeof (struct queue_t));
queue->head = queue->tail = NULL;
if (pthread_mutex_init(&(queue->mutex), NULL) != 0) {
// log_error("pthread_mutex_init failed");
exit(1);
}
if (pthread_cond_init(&(queue->cond), NULL) != 0) {
//log_error("pthread_cond_init failed");
exit(1);
}
queue->count = 0;
return queue;
}
void enqueue(Queue queue, void* data) {
pthread_mutex_lock(&queue->mutex);
Item item = create_item(data);
if (queue->tail == NULL) {
queue->head = queue->tail = item;
} else {
queue->tail->next = item;
queue->tail = item;
}
queue->count++;
pthread_cond_signal(&queue->cond);
pthread_mutex_unlock(&queue->mutex);
}
void* dequeue(Queue queue) {
pthread_mutex_lock(&queue->mutex);
//log_debug("Thread %u granted the mutex to dequeue", pthread_self());
while (queue_is_empty(queue)){
pthread_cond_wait(&queue->cond, &queue->mutex);
}
void* data = queue->head->data;
queue->head = queue->head->next;
queue->count--;
if (queue->count == 0) {
queue->head = queue->tail = NULL;
}
pthread_mutex_unlock(&queue->mutex);
return data;
}
int queue_is_empty(Queue queue) {
return queue->count == 0;
}