/*
  * Audio FIFO
  * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
  *

  * 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
  */
 
 /**
  * @file
  * Audio FIFO Buffer
  */
 
 #ifndef AVUTIL_AUDIO_FIFO_H
 #define AVUTIL_AUDIO_FIFO_H
 
 #include "avutil.h"
 #include "fifo.h"
 #include "samplefmt.h"
 
 /**
  * @addtogroup lavu_audio
  * @{

  *

  * @defgroup lavu_audiofifo Audio FIFO Buffer

  * @{

  */
 
 /**
  * Context for an Audio FIFO Buffer.
  *
  * - Operates at the sample level rather than the byte level.
  * - Supports multiple channels with either planar or packed sample format.
  * - Automatic reallocation when writing to a full buffer.
  */
 typedef struct AVAudioFifo AVAudioFifo;
 
 /**
  * Free an AVAudioFifo.
  *
  * @param af  AVAudioFifo to free
  */
 void av_audio_fifo_free(AVAudioFifo *af);
 
 /**
  * Allocate an AVAudioFifo.
  *
  * @param sample_fmt  sample format
  * @param channels    number of channels
  * @param nb_samples  initial allocation size, in samples
  * @return            newly allocated AVAudioFifo, or NULL on error
  */
 AVAudioFifo *av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels,
                                  int nb_samples);
 
 /**
  * Reallocate an AVAudioFifo.
  *
  * @param af          AVAudioFifo to reallocate
  * @param nb_samples  new allocation size, in samples
  * @return            0 if OK, or negative AVERROR code on failure
  */
 int av_audio_fifo_realloc(AVAudioFifo *af, int nb_samples);
 
 /**
  * Write data to an AVAudioFifo.
  *
  * The AVAudioFifo will be reallocated automatically if the available space
  * is less than nb_samples.
  *
  * @see enum AVSampleFormat
  * The documentation for AVSampleFormat describes the data layout.
  *
  * @param af          AVAudioFifo to write to
  * @param data        audio data plane pointers
  * @param nb_samples  number of samples to write
  * @return            number of samples actually written, or negative AVERROR

  *                    code on failure. If successful, the number of samples
  *                    actually written will always be nb_samples.

  */
 int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples);
 
 /**
  * Read data from an AVAudioFifo.
  *
  * @see enum AVSampleFormat
  * The documentation for AVSampleFormat describes the data layout.
  *
  * @param af          AVAudioFifo to read from
  * @param data        audio data plane pointers
  * @param nb_samples  number of samples to read
  * @return            number of samples actually read, or negative AVERROR code

  *                    on failure. The number of samples actually read will not
  *                    be greater than nb_samples, and will only be less than
  *                    nb_samples if av_audio_fifo_size is less than nb_samples.

  */
 int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples);
 
 /**
  * Drain data from an AVAudioFifo.
  *
  * Removes the data without reading it.
  *
  * @param af          AVAudioFifo to drain
  * @param nb_samples  number of samples to drain
  * @return            0 if OK, or negative AVERROR code on failure
  */
 int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples);
 
 /**
  * Reset the AVAudioFifo buffer.
  *
  * This empties all data in the buffer.
  *
  * @param af  AVAudioFifo to reset
  */
 void av_audio_fifo_reset(AVAudioFifo *af);
 
 /**
  * Get the current number of samples in the AVAudioFifo available for reading.
  *
  * @param af  the AVAudioFifo to query
  * @return    number of samples available for reading
  */
 int av_audio_fifo_size(AVAudioFifo *af);
 
 /**
  * Get the current number of samples in the AVAudioFifo available for writing.
  *
  * @param af  the AVAudioFifo to query
  * @return    number of samples available for writing
  */
 int av_audio_fifo_space(AVAudioFifo *af);
 
 /**
  * @}

  * @}

  */
 
 #endif /* AVUTIL_AUDIO_FIFO_H */