+
+void print_volume(yajl_gen json_gen, char *buffer, const char *fmt, const char *fmt_muted, const char *device, const char *mixer, int mixer_idx) {
+ char *outwalk = buffer;
+ int pbval = 1;
+
+ /* Printing volume works with ALSA and PulseAudio at the moment */
+ if (output_format == O_I3BAR) {
+ char *instance;
+ asprintf(&instance, "%s.%s.%d", device, mixer, mixer_idx);
+ INSTANCE(instance);
+ free(instance);
+ }
+
+#if !defined(__DragonFly__) && !defined(__OpenBSD__)
+ /* Try PulseAudio first */
+
+ /* If the device name has the format "pulse[:N]" where N is the
+ * index of the PulseAudio sink then force PulseAudio, optionally
+ * overriding the default sink */
+ if (!strncasecmp(device, "pulse", strlen("pulse"))) {
+ uint32_t sink_idx = device[strlen("pulse")] == ':' ? (uint32_t)atoi(device + strlen("pulse:")) : DEFAULT_SINK_INDEX;
+ const char *sink_name = device[strlen("pulse")] == ':' &&
+ !isdigit(device[strlen("pulse:")])
+ ? device + strlen("pulse:")
+ : NULL;
+ int cvolume = 0;
+ char description[MAX_SINK_DESCRIPTION_LEN] = {'\0'};
+
+ if (pulse_initialize()) {
+ cvolume = volume_pulseaudio(sink_idx, sink_name);
+ /* false result means error, stick to empty-string */
+ if (!description_pulseaudio(sink_idx, sink_name, description)) {
+ description[0] = '\0';
+ }
+ }
+
+ int ivolume = DECOMPOSE_VOLUME(cvolume);
+ bool muted = DECOMPOSE_MUTED(cvolume);
+ if (muted) {
+ START_COLOR("color_degraded");
+ pbval = 0;
+ }
+
+ /* negative result means error, stick to 0 */
+ if (ivolume < 0)
+ ivolume = 0;
+ outwalk = apply_volume_format(muted ? fmt_muted : fmt,
+ outwalk,
+ ivolume,
+ description);
+ goto out;
+ } else if (!strcasecmp(device, "default") && pulse_initialize()) {
+ /* no device specified or "default" set */
+ char description[MAX_SINK_DESCRIPTION_LEN];
+ bool success = description_pulseaudio(DEFAULT_SINK_INDEX, NULL, description);
+ int cvolume = volume_pulseaudio(DEFAULT_SINK_INDEX, NULL);
+ int ivolume = DECOMPOSE_VOLUME(cvolume);
+ bool muted = DECOMPOSE_MUTED(cvolume);
+ if (ivolume >= 0 && success) {
+ if (muted) {
+ START_COLOR("color_degraded");
+ pbval = 0;
+ }
+ outwalk = apply_volume_format(muted ? fmt_muted : fmt,
+ outwalk,
+ ivolume,
+ description);
+ goto out;
+ }
+ /* negative result or NULL description means error, fail PulseAudio attempt */
+ }
+/* If some other device was specified or PulseAudio is not detected,
+ * proceed to ALSA / OSS */
+#endif
+
+#ifdef __linux__
+ const long MAX_LINEAR_DB_SCALE = 24;
+ int err;
+ snd_mixer_t *m;
+ snd_mixer_selem_id_t *sid;
+ snd_mixer_elem_t *elem;
+ long min, max, val;
+ const char *mixer_name;
+ bool force_linear = false;
+ int avg;
+
+ if ((err = snd_mixer_open(&m, 0)) < 0) {
+ fprintf(stderr, "i3status: ALSA: Cannot open mixer: %s\n", snd_strerror(err));
+ goto out;
+ }
+
+ /* Attach this mixer handle to the given device */
+ if ((err = snd_mixer_attach(m, device)) < 0) {
+ fprintf(stderr, "i3status: ALSA: Cannot attach mixer to device: %s\n", snd_strerror(err));
+ snd_mixer_close(m);
+ goto out;
+ }
+
+ /* Register this mixer */
+ if ((err = snd_mixer_selem_register(m, NULL, NULL)) < 0) {
+ fprintf(stderr, "i3status: ALSA: snd_mixer_selem_register: %s\n", snd_strerror(err));
+ snd_mixer_close(m);
+ goto out;
+ }
+
+ if ((err = snd_mixer_load(m)) < 0) {
+ fprintf(stderr, "i3status: ALSA: snd_mixer_load: %s\n", snd_strerror(err));
+ snd_mixer_close(m);
+ goto out;
+ }
+
+ snd_mixer_selem_id_malloc(&sid);
+ if (sid == NULL) {
+ snd_mixer_close(m);
+ goto out;
+ }
+
+ /* Find the given mixer */
+ snd_mixer_selem_id_set_index(sid, mixer_idx);
+ snd_mixer_selem_id_set_name(sid, mixer);
+ if (!(elem = snd_mixer_find_selem(m, sid))) {
+ fprintf(stderr, "i3status: ALSA: Cannot find mixer %s (index %u)\n",
+ snd_mixer_selem_id_get_name(sid), snd_mixer_selem_id_get_index(sid));
+ snd_mixer_close(m);
+ snd_mixer_selem_id_free(sid);
+ goto out;
+ }
+
+ /* Get the volume range to convert the volume later */
+ snd_mixer_handle_events(m);
+ if (!strncasecmp(mixer, "capture", strlen("capture"))) {
+ ALSA_VOLUME(capture)
+ } else {
+ ALSA_VOLUME(playback)
+ }
+
+ if (err != 0) {
+ fprintf(stderr, "i3status: ALSA: Cannot get playback volume.\n");
+ goto out;
+ }
+
+ mixer_name = snd_mixer_selem_get_name(elem);
+ if (!mixer_name) {
+ fprintf(stderr, "i3status: ALSA: NULL mixer_name.\n");
+ goto out;
+ }
+
+ /* Use linear mapping for raw register values or small ranges of 24 dB */
+ if (force_linear || max - min <= MAX_LINEAR_DB_SCALE * 100) {
+ float avgf = ((float)(val - min) / (max - min)) * 100;
+ avg = (int)avgf;
+ avg = (avgf - avg < 0.5 ? avg : (avg + 1));
+ } else {
+ /* mapped volume to be more natural for the human ear */
+ double normalized = exp10((val - max) / 6000.0);
+ if (min != SND_CTL_TLV_DB_GAIN_MUTE) {
+ double min_norm = exp10((min - max) / 6000.0);
+ normalized = (normalized - min_norm) / (1 - min_norm);
+ }
+ avg = lround(normalized * 100);
+ }
+
+ /* Check for mute */
+ if (snd_mixer_selem_has_playback_switch(elem)) {
+ ALSA_MUTE_SWITCH(playback)
+ } else if (snd_mixer_selem_has_capture_switch(elem)) {
+ ALSA_MUTE_SWITCH(capture)
+ }
+
+ outwalk = apply_volume_format(fmt, outwalk, avg, mixer_name);
+
+ snd_mixer_close(m);
+ snd_mixer_selem_id_free(sid);
+