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queue.c
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queue.c
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#include <stdlib.h>
#include <stdbool.h>
#include "queue.h"
void init_queue(struct queue_t *queue, int size)
{
queue->items = (void *)(malloc(size * sizeof(void *)));
queue->max = size;
queue->start = queue->end = queue->size = 0;
}
bool queue_empty(struct queue_t *queue)
{
return !queue->size;
}
bool queue_full(struct queue_t *queue)
{
return queue->size == queue->max;
}
bool queue_push(struct queue_t *queue, void *item)
{
if (queue_full(queue))
return false;
*(queue->items + queue->end) = item;
queue->end = (queue->end + 1) % queue->max;
++queue->size;
return true;
}
void *queue_pop(struct queue_t *queue)
{
void *element;
if (queue_empty(queue))
return NULL;
element = *(queue->items + queue->start);
queue->start = (queue->start + 1) % queue->max;
--queue->size;
return element;
}
void free_queue(struct queue_t *queue)
{
free(queue->items);
}