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// Jack Sangdahl
// CSCI3753 SP24
// PA4 Shared Array
#include "array.h"

int array_init(array *q) {
  q->head = 0;
  q->tail = 0;
  pthread_mutex_init(&q->lock, NULL);
  sem_init(&q->avail, 0, ARRAY_SIZE);
  sem_init(&q->empty, 0, 0);
  return 0;
}

int array_put(array *q, char *hostname) {
  sem_wait(&q->avail);
  pthread_mutex_lock(&q->lock);
  q->data[q->tail++] = hostname;
  q->tail %= ARRAY_SIZE;
  pthread_mutex_unlock(&q->lock);
  sem_post(&q->empty);
  return 0;
}

int array_get(array *q, char **hostname) {
  sem_wait(&q->empty);
  pthread_mutex_lock(&q->lock);
  *hostname = q->data[q->head++];
  q->head %= ARRAY_SIZE;
  pthread_mutex_unlock(&q->lock);
  sem_post(&q->avail);
  return 0;
}

void array_free(array *q) {
  pthread_mutex_destroy(&q->lock);
  sem_destroy(&q->avail);
  sem_destroy(&q->empty);
}