/*
 * utils for libavcodec
 * Copyright (c) 2001 Fabrice Bellard
 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
 *
 * 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
 * utils.
 */

#include "util_internal.h"
#include "avcodec.h"
#include "compat.h"
#include "channel_layout.h"
#include "common.h"
#include "mathematics.h"
#include "samplefmt.h"
#include "avcodec.h"
#include "bytestream.h"
#include "version.h"
#include <stdlib.h>
#include <stdarg.h>
#include <limits.h>
#include <float.h>

int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, void **options)
{
    if ((codec && avctx->codec && codec != avctx->codec)) {
        av_log(avctx, AV_LOG_ERROR, "This AVCodecContext was allocated for %s, "
                                    "but %s passed to avcodec_open2()\n", avctx->codec->name, codec->name);
        return AVERROR(EINVAL);
    }
    if (!codec)
        codec = avctx->codec;

    if (avctx->extradata_size < 0 || avctx->extradata_size >= FF_MAX_EXTRADATA_SIZE)
        return AVERROR(EINVAL);

	int ret = 0;

    if (codec->priv_data_size > 0) {
        if (!avctx->priv_data) {
            avctx->priv_data = av_mallocz(codec->priv_data_size);
            if (!avctx->priv_data) {
                ret = AVERROR(ENOMEM);
                goto end;
            }
            if (codec->priv_class) {
                *(const AVClass **)avctx->priv_data = codec->priv_class;
            }
        }
    } else {
        avctx->priv_data = NULL;
    }

    if (avctx->channels > FF_SANE_NB_CHANNELS) {
        ret = AVERROR(EINVAL);
        goto free_and_end;
    }

    avctx->codec = codec;
    avctx->codec_id   = codec->id;
   
    avctx->frame_number = 0;

    if (avctx->codec->init) {
        ret = avctx->codec->init(avctx);
        if (ret < 0) {
            goto free_and_end;
        }
    }

    ret=0;

    /* validate channel layout from the decoder */
    if (avctx->channel_layout) {
        int channels = av_get_channel_layout_nb_channels(avctx->channel_layout);
        if (!avctx->channels)
            avctx->channels = channels;
        else if (channels != avctx->channels) {
			char buf[512] = "";
            av_log(avctx, AV_LOG_WARNING,
                    "Channel layout '%s' with %d channels does not match specified number of channels %d: "
                    "ignoring specified channel layout\n",
                    buf, channels, avctx->channels);
            avctx->channel_layout = 0;
        }
    }
    if (avctx->channels && avctx->channels < 0 ||
        avctx->channels > FF_SANE_NB_CHANNELS) {
        ret = AVERROR(EINVAL);
        goto free_and_end;
    }
    if (codec->priv_data_size > 0 && avctx->priv_data && codec->priv_class) {
        av_assert0(*(const AVClass **)avctx->priv_data == codec->priv_class);
    }

end:

    return ret;
free_and_end:
    if (avctx->codec)
        avctx->codec->close(avctx);

    av_freep(&avctx->priv_data);
    avctx->codec = NULL;
    goto end;
}

av_cold int avcodec_close(AVCodecContext *avctx)
{
    int i;

    if (!avctx)
        return 0;

    if (avctx->codec && avctx->codec->close)
        avctx->codec->close(avctx);
    av_freep(&avctx->priv_data);
    avctx->codec = NULL;
    return 0;
}

void avcodec_flush_buffers(AVCodecContext *avctx)
{
    if (avctx->codec->flush)
        avctx->codec->flush(avctx);
}