C++ snd_ctl_elem_value_alloca函数代码示例

static int
_phoneui_utils_sound_volume_mute_changed_cb(snd_hctl_elem_t *elem, unsigned int mask)
{
	snd_ctl_elem_value_t *control;
	enum SoundControlType type;
	int mute;


        if (mask == SND_CTL_EVENT_MASK_REMOVE)
                return 0;
        if (mask & SND_CTL_EVENT_MASK_VALUE) {
                snd_ctl_elem_value_alloca(&control);
                snd_hctl_elem_read(elem, control);
                type = _phoneui_utils_sound_volume_mute_element_to_type(elem);
                if (type != CONTROL_END) {
			mute = phoneui_utils_sound_volume_mute_get(type);
			g_debug("Got alsa mute change for control type '%d', new value: %d",
				type, mute);
			if (_phoneui_utils_sound_volume_mute_changed_callback) {
				_phoneui_utils_sound_volume_mute_changed_callback(type, mute, _phoneui_utils_sound_volume_mute_changed_userdata);
			}
		}
        }
	return 0;
}

int
phoneui_utils_sound_volume_mute_set(enum SoundControlType type, int mute)
{
	int err;

	snd_hctl_elem_t *elem;
	snd_ctl_elem_value_t *control;

	elem = controls[STATE_INDEX][type].mute_element;
	if (!elem) {
		return -1;
	}
	snd_ctl_elem_value_alloca(&control);

	snd_ctl_elem_value_set_boolean(control, 0, !mute);

	err = snd_hctl_elem_write(elem, control);
	if (err) {
		g_warning("%s", snd_strerror(err));
		return -1;
	}
	g_debug("Set control %d to %d", type, mute);

	return 0;
}

static int 
hammerfall_set_input_monitor_mask (jack_hardware_t *hw, unsigned long mask)
{
	hammerfall_t *h = (hammerfall_t *) hw->private_hw;
	snd_ctl_elem_value_t *ctl;
	snd_ctl_elem_id_t *ctl_id;
	int err;
	int i;
	
	snd_ctl_elem_value_alloca (&ctl);
	snd_ctl_elem_id_alloca (&ctl_id);
	set_control_id (ctl_id, "Channels Thru");
	snd_ctl_elem_value_set_id (ctl, ctl_id);
	
	for (i = 0; i < 26; i++) {
		snd_ctl_elem_value_set_integer (ctl, i, (mask & (1<<i)) ? 1 : 0);
	}
	
	if ((err = snd_ctl_elem_write (h->driver->ctl_handle, ctl)) != 0) {
		jack_error ("ALSA/Hammerfall: cannot set input monitoring (%s)", snd_strerror (err));
		return -1;
	}
	
	hw->input_monitor_mask = mask;

	return 0;
}

long
phoneui_utils_sound_volume_raw_get(enum SoundControlType type)
{
	int err;
	long value;
	unsigned int i,count;

	snd_ctl_elem_value_t *control;
	snd_ctl_elem_value_alloca(&control);

	snd_hctl_elem_t *elem;

	count = controls[STATE_INDEX][type].count;
	elem = controls[STATE_INDEX][type].element;
	if (!elem || !count) {
		return 0;
	}

	err = snd_hctl_elem_read(elem, control);
	if (err < 0) {
		g_warning("%s", snd_strerror(err));
		return -1;
	}

	value = 0;
	/* FIXME: possible long overflow */
	for (i = 0 ; i < count ; i++) {
		value += snd_ctl_elem_value_get_integer(control, i);
	}
	value /= count;

	return value;
}

int
phoneui_utils_sound_volume_raw_set(enum SoundControlType type, long value)
{
	int err;
	unsigned int i, count;

	snd_hctl_elem_t *elem;
	snd_ctl_elem_value_t *control;


	elem = controls[STATE_INDEX][type].element;
	if (!elem) {
		return -1;
	}
	snd_ctl_elem_value_alloca(&control);
	count = controls[STATE_INDEX][type].count;

	for (i = 0 ; i < count ; i++) {
		snd_ctl_elem_value_set_integer(control, i, value);
	}

	err = snd_hctl_elem_write(elem, control);
	if (err) {
		g_warning("%s", snd_strerror(err));
		return -1;
	}

	/* FIXME put it somewhere else, this is not the correct place! */
	phoneui_utils_sound_volume_save(type);

	return 0;
}

void patchbay_init(void)
{
	int i;
	int nb_active_channels;
	snd_ctl_elem_value_t *val;

	snd_ctl_elem_value_alloca(&val);
	snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
	snd_ctl_elem_value_set_name(val, ANALOG_PLAYBACK_ROUTE_NAME);
	memset (stream_active, 0, (MAX_OUTPUT_CHANNELS + MAX_SPDIF_CHANNELS) * sizeof(int));
	nb_active_channels = 0;
	for (i = 0; i < output_channels; i++) {
		snd_ctl_elem_value_set_numid(val, 0);
		snd_ctl_elem_value_set_index(val, i);
		if (snd_ctl_elem_read(ctl, val) < 0)
			continue;

		stream_active[i] = 1;
		nb_active_channels++;
	}
	output_channels = nb_active_channels;
	snd_ctl_elem_value_set_name(val, SPDIF_PLAYBACK_ROUTE_NAME);
	nb_active_channels = 0;
	for (i = 0; i < spdif_channels; i++) {
		snd_ctl_elem_value_set_numid(val, 0);
		snd_ctl_elem_value_set_index(val, i);
 		if (snd_ctl_elem_read(ctl, val) < 0)
			continue;
		stream_active[i + MAX_OUTPUT_CHANNELS] = 1;
		nb_active_channels++;
	}
	spdif_channels = nb_active_channels;
}

static int 
hammerfall_change_sample_clock (jack_hardware_t *hw, SampleClockMode mode) 
{
	hammerfall_t *h = (hammerfall_t *) hw->private_hw;
	snd_ctl_elem_value_t *ctl;
	snd_ctl_elem_id_t *ctl_id;
	int err;

	snd_ctl_elem_value_alloca (&ctl);
	snd_ctl_elem_id_alloca (&ctl_id);
	set_control_id (ctl_id, "Sync Mode");
	snd_ctl_elem_value_set_id (ctl, ctl_id);

	switch (mode) {
	case AutoSync:
		snd_ctl_elem_value_set_enumerated (ctl, 0, 0);
		break;
	case ClockMaster:
		snd_ctl_elem_value_set_enumerated (ctl, 0, 1);
		break;
	case WordClock:
		snd_ctl_elem_value_set_enumerated (ctl, 0, 2);
		break;
	}

	if ((err = snd_ctl_elem_write (h->driver->ctl_handle, ctl)) < 0) {
		jack_error ("ALSA-Hammerfall: cannot set clock mode");
	}

	return 0;
}

static void set_routes(int stream, int idx)
{
	int err;
	unsigned int out;
	snd_ctl_elem_value_t *val;

	stream--;
	if (stream < 0 || stream > 9) {
		g_print("set_routes (1)\n");
		return;
	}
	if (! stream_active[stream])
		return;
	out = 0;
	if (idx == 1)
		out = MAX_INPUT_CHANNELS + MAX_SPDIF_CHANNELS + 1;
	else if (idx == 2 || idx == 3)	/* S/PDIF left & right */
		out = idx + 7; /* 9-10 */
	else if (idx >= 4) /* analog */
		out = idx - 3; /* 1-8 */

	snd_ctl_elem_value_alloca(&val);
	snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
	if (stream >= MAX_OUTPUT_CHANNELS) {
		snd_ctl_elem_value_set_name(val, SPDIF_PLAYBACK_ROUTE_NAME);
		snd_ctl_elem_value_set_index(val, stream - MAX_OUTPUT_CHANNELS);
	} else {
		snd_ctl_elem_value_set_name(val, ANALOG_PLAYBACK_ROUTE_NAME);
		snd_ctl_elem_value_set_index(val, stream);
	}

	snd_ctl_elem_value_set_enumerated(val, 0, out);
	if ((err = snd_ctl_elem_write(ctl, val)) < 0)
		g_print("Multi track route write error: %s\n", snd_strerror(err));
}

static int get_toggle_index(int stream)
{
	int err, out;
	snd_ctl_elem_value_t *val;

	stream--;
	if (stream < 0 || stream > 9) {
		g_print("get_toggle_index (1)\n");
		return 0;
	}
	snd_ctl_elem_value_alloca(&val);
	snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
	if (stream >= MAX_OUTPUT_CHANNELS) {
		snd_ctl_elem_value_set_name(val, SPDIF_PLAYBACK_ROUTE_NAME);
		snd_ctl_elem_value_set_index(val, stream - MAX_OUTPUT_CHANNELS);
	} else {
		snd_ctl_elem_value_set_name(val, ANALOG_PLAYBACK_ROUTE_NAME);
		snd_ctl_elem_value_set_index(val, stream);
	}
	if ((err = snd_ctl_elem_read(ctl, val)) < 0)
		return 0;
	out = snd_ctl_elem_value_get_enumerated(val, 0);
	if (out >= MAX_INPUT_CHANNELS + MAX_SPDIF_CHANNELS + 1) {
		if (stream >= MAX_PCM_OUTPUT_CHANNELS || stream < MAX_SPDIF_CHANNELS)
			return 1; /* digital mixer */
	} else if (out >= MAX_INPUT_CHANNELS + 1)
		return out - (MAX_INPUT_CHANNELS + 1) + 2; /* spdif left (=2) / right (=3) */
	else if (out >= 1)
		return out + spdif_channels + 1; /* analog (4-) */

	return 0; /* pcm */
}

void ipga_volume_update(int idx)
{
	snd_ctl_elem_value_t *val;
	int err, ipga_vol;
	snd_ctl_elem_value_alloca(&val);
	snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
	snd_ctl_elem_value_set_name(val, IPGA_VOLUME_NAME);
	snd_ctl_elem_value_set_index(val, idx);
	if ((err = snd_ctl_elem_read(ctl, val)) < 0) {
		g_print("Unable to read ipga volume: %s\n", snd_strerror(err));
		return;
	}
	gtk_adjustment_set_value(GTK_ADJUSTMENT(av_ipga_volume_adj[idx]),
				 -(ipga_vol = snd_ctl_elem_value_get_integer(val, 0)));
	snd_ctl_elem_value_set_name(val, ADC_VOLUME_NAME);
	snd_ctl_elem_value_set_index(val, idx);
	if ((err = snd_ctl_elem_read(ctl, val)) < 0) {
		g_print("Unable to read adc volume: %s\n", snd_strerror(err));
		return;
	}
	// set ADC volume to max if IPGA volume greater 0
	if (ipga_vol)
		gtk_adjustment_set_value(GTK_ADJUSTMENT(av_adc_volume_adj[idx]),
					 -adc_max);
}

static int set_enum_item_ops(snd_mixer_elem_t *elem,
			     snd_mixer_selem_channel_id_t channel,
			     unsigned int item)
{
	selem_none_t *s = snd_mixer_elem_get_private(elem);
	snd_ctl_elem_value_t *ctl;
	snd_hctl_elem_t *helem;
	int err;
	int type;

	if ((unsigned int) channel >= s->str[0].channels) {
		return -EINVAL;
	}
	type = CTL_GLOBAL_ENUM;
	helem = s->ctls[type].elem;
	if (!helem) {
		type = CTL_PLAYBACK_ENUM;
		helem = s->ctls[type].elem;
	}
	if (!helem) {
		type = CTL_CAPTURE_ENUM;
		helem = s->ctls[type].elem;
	}
	assert(helem);
	if (item >= (unsigned int)s->ctls[type].max) {
		return -EINVAL;
	}
	snd_ctl_elem_value_alloca(&ctl);
	err = snd_hctl_elem_read(helem, ctl);
	if (err < 0) {
		return err;
	}
	snd_ctl_elem_value_set_enumerated(ctl, channel, item);
	return snd_hctl_elem_write(helem, ctl);
}

static int elem_read_enum(selem_none_t *s)
{
	snd_ctl_elem_value_t *ctl;
	unsigned int idx;
	int err;
	int type;
	selem_ctl_t *c;
	type = CTL_GLOBAL_ENUM;
	if ( (s->selem.caps & (SM_CAP_CENUM | SM_CAP_PENUM)) == (SM_CAP_CENUM | SM_CAP_PENUM) )
		type = CTL_GLOBAL_ENUM;
	else if (s->selem.caps & SM_CAP_PENUM)
		type = CTL_PLAYBACK_ENUM;
	else if (s->selem.caps & SM_CAP_CENUM)
		type = CTL_CAPTURE_ENUM;
	c = &s->ctls[type];
	snd_ctl_elem_value_alloca(&ctl);
	if ((err = snd_hctl_elem_read(c->elem, ctl)) < 0)
		return err;
	for (idx = 0; idx < s->str[0].channels; idx++) {
		unsigned int idx1 = idx;
		if (idx >= c->values)
			idx1 = 0;
		s->str[0].vol[idx] = snd_ctl_elem_value_get_enumerated(ctl, idx1);
	}
	return 0;
}

void audio_set_default_levels() {
  int err;
  snd_ctl_t *ctl;
  snd_ctl_elem_value_t *val;

  snd_ctl_elem_value_alloca(&val);

  if (snd_ctl_open(&ctl, ALSA_DEVICE, 0)) {
    fprintf(stderr, "can't open audio device");
    return;
  }

  /* unmute microphone */
  snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
  snd_ctl_elem_value_set_name(val, "Mic Capture Switch");
  snd_ctl_elem_value_set_integer(val, 0, 1);
  err = snd_ctl_elem_write(ctl, val);
  if (err)
    fprintf(stderr, "can't unmute microphone: %s\n", snd_strerror(err));

  /* unmute speaker */
  snd_ctl_elem_value_clear(val);
  snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
  snd_ctl_elem_value_set_name(val, "Speaker Playback Switch");
  snd_ctl_elem_value_set_integer(val, 0, 1);
  err = snd_ctl_elem_write(ctl, val);
  if (err)
    fprintf(stderr, "can't unmute speaker: %s\n", snd_strerror(err));

  /* set mic volume */
  snd_ctl_elem_value_clear(val);
  snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
  snd_ctl_elem_value_set_name(val, "Mic Capture Volume");
  snd_ctl_elem_value_set_integer(val, 0, DEFAULT_MIC_VOL);
  err = snd_ctl_elem_write(ctl, val);
  if (err)
    fprintf(stderr, "can't set microphone volume: %s\n", snd_strerror(err));

  /* set speaker volume */
  snd_ctl_elem_value_clear(val);
  snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
  snd_ctl_elem_value_set_name(val, "Speaker Playback Volume");
  snd_ctl_elem_value_set_integer(val, 0, DEFAULT_SPKR_VOL);
  snd_ctl_elem_value_set_integer(val, 1, DEFAULT_SPKR_VOL);
  err = snd_ctl_elem_write(ctl, val);
  if (err)
    fprintf(stderr, "can't set speaker volume: %s\n", snd_strerror(err));

  /* set capture source */
  snd_ctl_elem_value_clear(val);
  snd_ctl_elem_value_set_interface(val, SND_CTL_ELEM_IFACE_MIXER);
  snd_ctl_elem_value_set_name(val, "PCM Capture Source");
  snd_ctl_elem_value_set_integer(val, 0, 0);
  err = snd_ctl_elem_write(ctl, val);
  if (err)
    fprintf(stderr, "can't set capture source: %s\n", snd_strerror(err));

  snd_ctl_close(ctl);
}

bool CAESinkALSA::GetELD(snd_hctl_t *hctl, int device, CAEDeviceInfo& info, bool& badHDMI)
{
  badHDMI = false;

  snd_ctl_elem_id_t    *id;
  snd_ctl_elem_info_t  *einfo;
  snd_ctl_elem_value_t *control;
  snd_hctl_elem_t      *elem;

  snd_ctl_elem_id_alloca(&id);
  memset(id, 0, snd_ctl_elem_id_sizeof());

  snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_PCM);
  snd_ctl_elem_id_set_name     (id, "ELD" );
  snd_ctl_elem_id_set_device   (id, device);
  elem = snd_hctl_find_elem(hctl, id);
  if (!elem)
    return false;

  snd_ctl_elem_info_alloca(&einfo);
  memset(einfo, 0, snd_ctl_elem_info_sizeof());

  if (snd_hctl_elem_info(elem, einfo) < 0)
    return false;

  if (!snd_ctl_elem_info_is_readable(einfo))
    return false;

  if (snd_ctl_elem_info_get_type(einfo) != SND_CTL_ELEM_TYPE_BYTES)
    return false;

  snd_ctl_elem_value_alloca(&control);
  memset(control, 0, snd_ctl_elem_value_sizeof());

  if (snd_hctl_elem_read(elem, control) < 0)
    return false;

  int dataLength = snd_ctl_elem_info_get_count(einfo);
  /* if there is no ELD data, then its a bad HDMI device, either nothing attached OR an invalid nVidia HDMI device
   * OR the driver doesn't properly support ELD (notably ATI/AMD, 2012-05) */
  if (!dataLength)
    badHDMI = true;
  else
    CAEELDParser::Parse(
      (const uint8_t*)snd_ctl_elem_value_get_bytes(control),
      dataLength,
      info
    );

  info.m_deviceType = AE_DEVTYPE_HDMI;
  return true;
}

int get_gain(int idx, int src, int dst)
{
  int err;
  int val = HDSPMM_ERROR_NO_CARD;

  snd_ctl_elem_id_t *id;
  snd_ctl_elem_value_t *ctl;
  snd_ctl_t *handle;

  if(idx >= HDSPMM_MAX_CARDS || idx < 0)
	return HDSPMM_ERROR_WRONG_IDX;


  snd_ctl_elem_value_alloca(&ctl);
  snd_ctl_elem_id_alloca(&id);
  snd_ctl_elem_id_set_name(id, "Mixer");
  snd_ctl_elem_id_set_numid(id, 0);
  snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_HWDEP);
  snd_ctl_elem_id_set_device(id, 0);
  snd_ctl_elem_id_set_subdevice(id, 0);
  snd_ctl_elem_id_set_index(id, 0);
  snd_ctl_elem_value_set_id(ctl, id);

  if ((err = snd_ctl_open(&handle, card_name[cardid], SND_CTL_NONBLOCK)) < 0) {
#ifndef QUIET
    fprintf(stderr, "Alsa error: %s\n", snd_strerror(err));
#endif
    return HDSPMM_ERROR_ALSA_OPEN;
  }

  snd_ctl_elem_value_set_integer(ctl, 0, src);
  snd_ctl_elem_value_set_integer(ctl, 1, dst);

  if ((err = snd_ctl_elem_read(handle, ctl)) < 0) {
#ifndef QUIET
    fprintf(stderr, "Alsa error: %s\n", snd_strerror(err));
#endif
    return HDSPMM_ERROR_ALSA_READ;
  }
  val = snd_ctl_elem_value_get_integer(ctl, 2);

  snd_ctl_close(handle);

  return val;
  
  SETFLOAT(x->x_at+1, delta);
  SETFLOAT(x->x_at+2, phi);
  outlet_list(x->x_out_para, &s_list, 3, x->x_at);
  outlet_anything(x->x_obj.ob_outlet, s, x->x_size2d+1, x->x_at);
}