Function av_buffer_realloc

libavutil/buffer.c:183–231

}

int av_buffer_realloc(AVBufferRef **pbuf, size_t size)
{
    AVBufferRef *buf = *pbuf;
    uint8_t *tmp;
    int ret;

    if (!buf) {
        /* allocate a new buffer with av_realloc(), so it will be reallocatable
         * later */
        uint8_t *data = av_realloc(NULL, size);
        if (!data)
            return AVERROR(ENOMEM);

        buf = av_buffer_create(data, size, av_buffer_default_free, NULL, 0);
        if (!buf) {
            av_freep(&data);
            return AVERROR(ENOMEM);
        }

        buf->buffer->flags_internal |= BUFFER_FLAG_REALLOCATABLE;
        *pbuf = buf;

        return 0;
    } else if (buf->size == size)
        return 0;

    if (!(buf->buffer->flags_internal & BUFFER_FLAG_REALLOCATABLE) ||
        !av_buffer_is_writable(buf) || buf->data != buf->buffer->data) {
        /* cannot realloc, allocate a new reallocable buffer and copy data */
        AVBufferRef *new = NULL;

        ret = av_buffer_realloc(&new, size);
        if (ret < 0)
            return ret;

        memcpy(new->data, buf->data, FFMIN(size, buf->size));

        buffer_replace(pbuf, &new);
        return 0;
    }

    tmp = av_realloc(buf->buffer->data, size);
    if (!tmp)
        return AVERROR(ENOMEM);

    buf->buffer->data = buf->data = tmp;
    buf->buffer->size = buf->size = size;
    return 0;
}

int av_buffer_replace(AVBufferRef **pdst, const AVBufferRef *src)
{