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/*
* V4L2 Codec decoding example application
* Kamil Debski <k.debski@samsung.com>
*
* Queue handling
*
* Copyright 2012 Samsung Electronics Co., Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#include "common.h"
#include "queue.h"
#include <pthread.h>
#include <stdlib.h>
int queue_init(struct queue *q, int size)
{
q->q = (int*)malloc(size * sizeof(int));
if (!q->q) {
err("Failed to init queue (malloc failed)");
return -1;
}
q->size = size;
q->head = 0;
q->tail = 0;
q->n = 0;
pthread_mutex_init(&q->mutex, NULL);
return 0;
}
int queue_add(struct queue *q, int e)
{
pthread_mutex_lock(&q->mutex);
if (q->n >= q->size) {
pthread_mutex_unlock(&q->mutex);
return -1;
}
q->q[q->head] = e;
q->head++;
q->head %= q->size;
q->n++;
pthread_mutex_unlock(&q->mutex);
return 0;
}
int queue_remove(struct queue *q)
{
int x;
pthread_mutex_lock(&q->mutex);
if (q->n == 0) {
pthread_mutex_unlock(&q->mutex);
return -1;
}
x = q->q[q->tail];
q->tail++;
q->tail %= q->size;
q->n--;
pthread_mutex_unlock(&q->mutex);
return x;
}
int queue_empty(struct queue *q)
{
int x;
pthread_mutex_lock(&q->mutex);
x = (q->n == 0);
pthread_mutex_unlock(&q->mutex);
return x;
}
void queue_free(struct queue *q)
{
free(q->q);
pthread_mutex_destroy(&q->mutex);
}
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