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queue.c
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queue.c
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#include "queue.h"
queue* queue_create() {
queue* q = malloc(sizeof(queue));
memset(q, 0, sizeof(queue));
return q;
}
void queue_push(queue* queue, void* item) {
node_t* tail = queue->tail;
node_t* next = malloc(sizeof(node_t));
next->next = NULL;
next->value = item;
if (tail) {
tail->next = next;
} else {
queue->head = next;
}
queue->tail = next;
++queue->size;
}
void* queue_pop(queue* queue) {
node_t* head = queue->head;
if (head) {
queue->head = head->next;
void* item = head->value;
if (!head->next)
queue->tail = NULL;
free(head);
--queue->size;
return item;
}
return NULL;
}
void* queue_peek(queue* queue) {
node_t* head = queue->head;
if (head) {
void* item = head->value;
return item;
}
return NULL;
}
void queue_destroy(queue* queue) {
node_t* next = queue->head;
while (next) {
node_t* tmp = next->next;
free(next);
next = tmp;
}
free(queue);
}