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

int array_init(array *s) {
  s->top = 0;
  sem_init(&s->mutex, 0, 1);
  sem_init(&s->avail, 0, ARRAY_SIZE);
  sem_init(&s->empty, 0, 0);
  return 0;
}

int array_put(array *s, char *hostname) {
  sem_wait(&s->avail);
  sem_wait(&s->mutex);
  s->data[s->top++] = hostname;
  sem_post(&s->mutex);
  sem_post(&s->empty);
  return 0;
}

int array_get(array *s, char **hostname) {
  sem_wait(&s->empty);
  sem_wait(&s->mutex);
  *hostname = s->data[--s->top];
  sem_post(&s->mutex);
  sem_post(&s->avail);
  return 0;
}

void array_free(array *s) {
  sem_destroy(&s->mutex);
  sem_destroy(&s->avail);
  sem_destroy(&s->empty);
}