GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavfilter/bufferqueue.h Lines: 16 22 72.7 %
Date: 2020-09-25 23:16:12 Branches: 3 8 37.5 %

Line Branch Exec Source
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/*
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 * Generic buffer queue
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 * Copyright (c) 2012 Nicolas George
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVFILTER_BUFFERQUEUE_H
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#define AVFILTER_BUFFERQUEUE_H
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/**
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 * FFBufQueue: simple AVFrame queue API
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 *
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 * Note: this API is not thread-safe. Concurrent access to the same queue
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 * must be protected by a mutex or any synchronization mechanism.
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 */
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/**
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 * Maximum size of the queue.
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 *
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 * This value can be overridden by definying it before including this
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 * header.
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 * Powers of 2 are recommended.
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 */
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#ifndef FF_BUFQUEUE_SIZE
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#define FF_BUFQUEUE_SIZE 64
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#endif
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#include "avfilter.h"
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#include "libavutil/avassert.h"
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/**
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 * Structure holding the queue
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 */
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struct FFBufQueue {
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    AVFrame *queue[FF_BUFQUEUE_SIZE];
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    unsigned short head;
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    unsigned short available; /**< number of available buffers */
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};
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#define BUCKET(i) queue->queue[(queue->head + (i)) % FF_BUFQUEUE_SIZE]
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/**
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 * Test if a buffer queue is full.
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 */
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static inline int ff_bufqueue_is_full(struct FFBufQueue *queue)
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{
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    return queue->available == FF_BUFQUEUE_SIZE;
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}
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/**
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 * Add a buffer to the queue.
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 *
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 * If the queue is already full, then the current last buffer is dropped
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 * (and unrefed) with a warning before adding the new buffer.
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 */
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static inline void ff_bufqueue_add(void *log, struct FFBufQueue *queue,
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                                   AVFrame *buf)
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{
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    if (ff_bufqueue_is_full(queue)) {
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        av_log(log, AV_LOG_WARNING, "Buffer queue overflow, dropping.\n");
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        av_frame_free(&BUCKET(--queue->available));
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    }
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    BUCKET(queue->available++) = buf;
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}
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/**
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 * Get a buffer from the queue without altering it.
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 *
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 * Buffer with index 0 is the first buffer in the queue.
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 * Return NULL if the queue has not enough buffers.
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 */
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static inline AVFrame *ff_bufqueue_peek(struct FFBufQueue *queue,
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                                        unsigned index)
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{
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    return index < queue->available ? BUCKET(index) : NULL;
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}
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/**
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 * Get the first buffer from the queue and remove it.
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 *
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 * Do not use on an empty queue.
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 */
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static inline AVFrame *ff_bufqueue_get(struct FFBufQueue *queue)
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{
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    AVFrame *ret = queue->queue[queue->head];
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    av_assert0(queue->available);
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    queue->available--;
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    queue->queue[queue->head] = NULL;
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    queue->head = (queue->head + 1) % FF_BUFQUEUE_SIZE;
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    return ret;
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}
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/**
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 * Unref and remove all buffers from the queue.
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 */
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static inline void ff_bufqueue_discard_all(struct FFBufQueue *queue)
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{
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    while (queue->available) {
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        AVFrame *buf = ff_bufqueue_get(queue);
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        av_frame_free(&buf);
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    }
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}
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#undef BUCKET
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#endif /* AVFILTER_BUFFERQUEUE_H */