ffmpeg/libavfilter/dnn/queue.h

118 lines
2.9 KiB
C

/*
* Copyright (c) 2020
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stddef.h>
#ifndef AVFILTER_DNN_QUEUE_H
#define AVFILTER_DNN_QUEUE_H
/**
* Linear double-ended data structure
*/
typedef struct Queue Queue;
/**
* @brief Create a Queue instance.
* It initializes the length of the Queue as 0.
*
* @return Pointer to the Queue
* @retval NULL if allocation fails
*/
Queue *ff_queue_create(void);
/**
* @brief Destroy the Queue instance.
* It also frees all elements of the Queue.
*/
void ff_queue_destroy(Queue *q);
/**
* @brief Return the length of the Queue
*/
size_t ff_queue_size(Queue *q);
/**
* @brief Return a pointer to the data
* at the head of the queue.
*
* @retval NULL if null pointer was passed
* or queue is empty
*/
void *ff_queue_peek_front(Queue *q);
/**
* @brief Return a pointer to the data at
* the tail of the queue.
*
* @retval NULL if null pointer was passed
* or queue is empty
*/
void *ff_queue_peek_back(Queue *q);
/**
* @brief Add data to the head of the queue.
* It increases the length of Queue by one.
*
* @param q pointer to the Queue.
* @param v data to be added
* @return The length of the Queue
* @retval 0 if the pointer to queue is NULL
* @retval -1 if new entry cannot be created
*/
int ff_queue_push_front(Queue *q, void *v);
/**
* @brief Add data to the tail of the queue.
* It increases the length of Queue by one.
*
* @param q pointer to the Queue
* @param v data to be added
* @return The length of the Queue
* @retval 0 if the pointer to queue is NULL
* @retval -1 if new entry cannot be created
*/
int ff_queue_push_back(Queue *q, void *v);
/**
* @brief Remove and free first element from
* the Queue. It shrinks the length of Queue
* by one.
*
* @param q pointer to the Queue.
* @return The value of first element as void.
* If a null pointer or empty queue is passed,
* it returns NULL
*/
void *ff_queue_pop_front(Queue *q);
/**
* @brief Remove and free last element from
* the Queue. It shrinks the length of Queue
* by one.
*
* @param q pointer to the Queue.
* @return The value of last element as void.
* If a null pointer or empty queue is passed,
* it returns NULL
*/
void *ff_queue_pop_back(Queue *q);
#endif