src/vdagent/vdagent-audio.c

   1 /*  vdagent-audio.c vdagentd audio handling code
   2
   3     Copyright 2015 Red Hat, Inc.
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #ifdef HAVE_CONFIG_H
  20 #include <config.h>
  21 #endif
  22
  23 #include <glib.h>
  24 #include <syslog.h>
  25 #include <stdbool.h>
  26 #include <alsa/asoundlib.h>
  27 #include <alsa/mixer.h>
  28 #include <alsa/error.h>
  29 #include "vdagent-audio.h"
  30
  31 #define ALSA_MUTE   0
  32 #define ALSA_UNMUTE 1
  33
  34 static snd_mixer_elem_t *
  35 get_alsa_default_mixer_by_name(snd_mixer_t **handle, const char *name)
  36 {
  37     snd_mixer_selem_id_t *sid;
  38     int err = 0;
  39
  40     if ((err = snd_mixer_open(handle, 0)) < 0)
  41         goto fail;
  42
  43     if ((err = snd_mixer_attach(*handle, "default")) < 0)
  44         goto fail;
  45
  46     if ((err = snd_mixer_selem_register(*handle, NULL, NULL)) < 0)
  47         goto fail;
  48
  49     if ((err = snd_mixer_load(*handle)) < 0)
  50         goto fail;
  51
  52     snd_mixer_selem_id_alloca(&sid);
  53     snd_mixer_selem_id_set_index(sid, 0);
  54     snd_mixer_selem_id_set_name(sid, name);
  55     return snd_mixer_find_selem(*handle, sid);
  56
  57 fail:
  58     syslog(LOG_WARNING, "%s fail: %s", __func__, snd_strerror(err));
  59     return NULL;
  60 }
  61
  62 static bool set_alsa_capture(uint8_t mute, uint8_t nchannels, uint16_t *volume)
  63 {
  64     snd_mixer_t *handle = NULL;
  65     snd_mixer_elem_t *e;
  66     long min, max, vol;
  67     bool ret = true;
  68     int alsa_mute;
  69
  70     e = get_alsa_default_mixer_by_name (&handle, "Capture");
  71     if (e == NULL) {
  72         syslog(LOG_WARNING, "vdagent-audio: can't get default alsa mixer");
  73         ret = false;
  74         goto end;
  75     }
  76
  77     alsa_mute = (mute) ? ALSA_MUTE : ALSA_UNMUTE;
  78     snd_mixer_selem_set_capture_switch_all(e, alsa_mute);
  79
  80     snd_mixer_selem_get_capture_volume_range(e, &min, &max);
  81     switch (nchannels) {
  82     case 1: /* MONO */
  83         vol = CLAMP(volume[0], min, max);
  84         snd_mixer_selem_set_capture_volume(e, SND_MIXER_SCHN_MONO, vol);
  85         syslog(LOG_DEBUG, "vdagent-audio: (capture-mono) %lu (%%%0.2f)",
  86                vol, (float) (100*vol/max));
  87         break;
  88     case 2: /* LEFT-RIGHT */
  89         vol = CLAMP(volume[0], min, max);
  90         snd_mixer_selem_set_capture_volume(e, SND_MIXER_SCHN_FRONT_LEFT, vol);
  91         syslog(LOG_DEBUG, "vdagent-audio: (capture-left) %lu (%%%0.2f)",
  92                vol, (float) (100*vol/max));
  93         vol = CLAMP(volume[1], min, max);
  94         snd_mixer_selem_set_capture_volume(e, SND_MIXER_SCHN_FRONT_RIGHT, vol);
  95         syslog(LOG_DEBUG, "vdagent-audio: (capture-right) %lu (%%%0.2f)",
  96                vol, (float) (100*vol/max));
  97         break;
  98     default:
  99         syslog(LOG_WARNING, "vdagent-audio: number of channels not supported");
 100         ret = false;
 101     }
 102 end:
 103     if (handle != NULL)
 104         snd_mixer_close(handle);
 105     return ret;
 106 }
 107
 108 static bool set_alsa_playback (uint8_t mute, uint8_t nchannels, uint16_t *volume)
 109 {
 110     snd_mixer_t *handle = NULL;
 111     snd_mixer_elem_t* e;
 112     long min, max, vol;
 113     bool ret = true;
 114     int alsa_mute;
 115
 116     e = get_alsa_default_mixer_by_name (&handle, "Master");
 117     if (e == NULL) {
 118         syslog(LOG_WARNING, "vdagent-audio: can't get default alsa mixer");
 119         ret = false;
 120         goto end;
 121     }
 122
 123     alsa_mute = (mute) ? ALSA_MUTE : ALSA_UNMUTE;
 124     snd_mixer_selem_set_playback_switch_all(e, alsa_mute);
 125
 126     snd_mixer_selem_get_playback_volume_range(e, &min, &max);
 127     switch (nchannels) {
 128     case 1: /* MONO */
 129         vol = CLAMP(volume[0], min, max);
 130         snd_mixer_selem_set_playback_volume(e, SND_MIXER_SCHN_MONO, vol);
 131         syslog(LOG_DEBUG, "vdagent-audio: (playback-mono) %lu (%%%0.2f)",
 132                vol, (float) (100*vol/max));
 133         break;
 134     case 2: /* LEFT-RIGHT */
 135         vol = CLAMP(volume[0], min, max);
 136         snd_mixer_selem_set_playback_volume(e, SND_MIXER_SCHN_FRONT_LEFT, vol);
 137         syslog(LOG_DEBUG, "vdagent-audio: (playback-left) %lu (%%%0.2f)",
 138                vol, (float) (100*vol/max));
 139         vol = CLAMP(volume[1], min, max);
 140         snd_mixer_selem_set_playback_volume(e, SND_MIXER_SCHN_FRONT_RIGHT, vol);
 141         syslog(LOG_DEBUG, "vdagent-audio: (playback-right) %lu (%%%0.2f)",
 142                vol, (float) (100*vol/max));
 143         break;
 144     default:
 145         syslog(LOG_WARNING, "vdagent-audio: number of channels not supported");
 146         ret = false;
 147     }
 148 end:
 149     if (handle != NULL)
 150         snd_mixer_close(handle);
 151     return ret;
 152 }
 153
 154 void vdagent_audio_playback_sync(uint8_t mute, uint8_t nchannels, uint16_t *volume)
 155 {
 156     syslog(LOG_DEBUG, "%s mute=%s nchannels=%u",
 157            __func__, (mute) ? "yes" : "no", nchannels);
 158     if (set_alsa_playback (mute, nchannels, volume) == false)
 159         syslog(LOG_WARNING, "Fail to sync playback volume");
 160 }
 161
 162 void vdagent_audio_record_sync(uint8_t mute, uint8_t nchannels, uint16_t *volume)
 163 {
 164     syslog(LOG_DEBUG, "%s mute=%s nchannels=%u",
 165            __func__, (mute) ? "yes" : "no", nchannels);
 166     if (set_alsa_capture (mute, nchannels, volume) == false)
 167         syslog(LOG_WARNING, "Fail to sync record volume");
 168 }