queue.c

/*
ssid-logger is a simple software to log SSID you encounter in your vicinity
Copyright © 2020-2022 solsTiCe d'Hiver
*/
#include <stdlib.h>
#include "queue.h"

queue_t *new_queue(int capacity)
{
  queue_t *q;
  q = malloc(sizeof(queue_t));

  if (q == NULL) {
    return q;
  }

  q->size = 0;
  q->max_size = capacity;
  q->head = NULL;
  q->tail = NULL;

  return q;
}

int enqueue(queue_t * q, void *value)
{
  if ((q->size + 1) > q->max_size) {
    return q->size;
  }

  struct Node *node = malloc(sizeof(struct Node));

  if (node == NULL) {
    return q->size;
  }

  node->value = value;
  node->next = NULL;

  if (q->head == NULL) {
    q->head = node;
    q->tail = node;
    q->size = 1;

    return q->size;
  }


  q->tail->next = node;
  q->tail = node;
  q->size += 1;

  return q->size;
}

void *dequeue(queue_t * q)
{
  if (q->size == 0) {
    return NULL;
  }

  void *value = NULL;
  struct Node *tmp = NULL;

  value = q->head->value;
  tmp = q->head;
  q->head = q->head->next;
  q->size -= 1;

  free(tmp);

  return value;
}

void free_queue(queue_t * q)
{
  if (q == NULL) {
    return;
  }

  while (q->head != NULL) {
    struct Node *tmp = q->head;
    q->head = q->head->next;
    if (tmp->value != NULL) {
      free(tmp->value);
    }

    free(tmp);
  }

  if (q->tail != NULL) {
    free(q->tail);
  }

  free(q);
}