代码审查所需的帮助. (大胆)(C)

static void do_write (void * data,gint samples)
{
    void * allocated = NULL;

    samples = flow_execute (get_postproc_flow (),& data,sizeof (gfloat) *
     samples,FMT_FLOAT,effect_rate,effect_channels) / sizeof (gfloat);

    if (data != allocated)
    {
        g_free (allocated);
        allocated = NULL;
    }

    apply_software_volume (data,output_channels,samples / output_channels);

    if (output_format != FMT_FLOAT)
    {
        void * new = g_malloc (FMT_SIZEOF (output_format) * samples);

        audio_to_int (data,new,output_format,samples);

        data = new;
        g_free (allocated);
        allocated = new;
    }

    if (output_format == FMT_S16_NE)
    {
        samples = flow_execute (get_legacy_flow (),2 * samples,output_rate,output_channels) / 2;

        if (data != allocated)
        {
            g_free (allocated);
            allocated = NULL;
        }
    }
    if (COP->buffer_free == NULL)
        COP->write_audio (data,FMT_SIZEOF (output_format) * samples);
    else
    {
        while (1)
        {
            gint ready = COP->buffer_free () / FMT_SIZEOF (output_format);

            ready = MIN (ready,samples);
            COP->write_audio (data,FMT_SIZEOF (output_format) * ready);
            data = (char *) data + FMT_SIZEOF (output_format) * ready;
            samples -= ready;

            if (samples == 0)
                break;

            g_usleep (50000);
        }
    }

    g_free (allocated);
}

//This function is where COP->write_audio point to.

static void output_write_audio (void * data,gint size)
{
    gint samples = size / FMT_SIZEOF (decoder_format);
    void * allocated = NULL;

    LOCK;
    frames_written += samples / decoder_channels;
    UNLOCK;

    if (decoder_format != FMT_FLOAT)
    {
        gfloat * new = g_malloc (sizeof (gfloat) * samples);

        audio_from_int (data,decoder_format,samples);

        data = new;
        g_free (allocated);
        allocated = new;
    }

    apply_replay_gain (data,samples);
    vis_runner_pass_audio (frames_written * 1000 / decoder_rate,data,samples,decoder_channels);
    new_effect_process ((gfloat * *) & data,& samples);

    if (data != allocated)
    {
        g_free (allocated);
        allocated = NULL;
    }

    do_write (data,samples);
    g_free (allocated);
}

Q1：void * allocated = NULL;
…
????if(数据！=已分配)
我很困惑..这是什么目的？我没有看到分配已更改

Q2.你可以看到CP-> write_audio将调用do_write,它将调用CP-> write_audio.什么时候会结束？