stream/ai_alsa1x.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <sys/time.h>
   4
   5 #include "config.h"
   6
   7 #include <alsa/asoundlib.h>
   8 #include "audio_in.h"
   9 #include "mp_msg.h"
  10 #include "help_mp.h"
  11
  12 int ai_alsa_setup(audio_in_t *ai)
  13 {
  14     snd_pcm_hw_params_t *params;
  15     snd_pcm_sw_params_t *swparams;
  16     snd_pcm_uframes_t buffer_size, period_size;
  17     int err;
  18     int dir;
  19     unsigned int rate;
  20
  21     snd_pcm_hw_params_alloca(&params);
  22     snd_pcm_sw_params_alloca(&swparams);
  23
  24     err = snd_pcm_hw_params_any(ai->alsa.handle, params);
  25     if (err < 0) {
  26         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_PcmBrokenConfig);
  27         return -1;
  28     }
  29
  30     err = snd_pcm_hw_params_set_access(ai->alsa.handle, params,
  31                                        SND_PCM_ACCESS_RW_INTERLEAVED);
  32     if (err < 0) {
  33         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_UnavailableAccessType);
  34         return -1;
  35     }
  36
  37     err = snd_pcm_hw_params_set_format(ai->alsa.handle, params, SND_PCM_FORMAT_S16_LE);
  38     if (err < 0) {
  39         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_UnavailableSampleFmt);
  40         return -1;
  41     }
  42
  43     err = snd_pcm_hw_params_set_channels(ai->alsa.handle, params, ai->req_channels);
  44     if (err < 0) {
  45         snd_pcm_hw_params_get_channels(params, &ai->channels);
  46         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_UnavailableChanCount,
  47                ai->channels);
  48     } else {
  49         ai->channels = ai->req_channels;
  50     }
  51
  52     dir = 0;
  53     rate = ai->req_samplerate;
  54     err = snd_pcm_hw_params_set_rate_near(ai->alsa.handle, params, &rate, &dir);
  55     if (err < 0) {
  56         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA1X_CannotSetSamplerate);
  57     }
  58     ai->samplerate = rate;
  59
  60     dir = 0;
  61     ai->alsa.buffer_time = 1000000;
  62     err = snd_pcm_hw_params_set_buffer_time_near(ai->alsa.handle, params,
  63                                                  &ai->alsa.buffer_time, &dir);
  64     if (err < 0) {
  65         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA1X_CannotSetBufferTime);
  66     }
  67
  68     dir = 0;
  69     ai->alsa.period_time = ai->alsa.buffer_time / 4;
  70     err = snd_pcm_hw_params_set_period_time_near(ai->alsa.handle, params,
  71                                                  &ai->alsa.period_time, &dir);
  72     if (err < 0) {
  73         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA1X_CannotSetPeriodTime);
  74     }
  75
  76     err = snd_pcm_hw_params(ai->alsa.handle, params);
  77     if (err < 0) {
  78         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_CannotInstallHWParams, snd_strerror(err));
  79         snd_pcm_hw_params_dump(params, ai->alsa.log);
  80         return -1;
  81     }
  82
  83     dir = -1;
  84     snd_pcm_hw_params_get_period_size(params, &period_size, &dir);
  85     snd_pcm_hw_params_get_buffer_size(params, &buffer_size);
  86     ai->alsa.chunk_size = period_size;
  87     if (period_size == buffer_size) {
  88         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_PeriodEqualsBufferSize, ai->alsa.chunk_size, (long)buffer_size);
  89         return -1;
  90     }
  91
  92     snd_pcm_sw_params_current(ai->alsa.handle, swparams);
  93     err = snd_pcm_sw_params_set_sleep_min(ai->alsa.handle, swparams,0);
  94     err = snd_pcm_sw_params_set_avail_min(ai->alsa.handle, swparams, ai->alsa.chunk_size);
  95
  96     err = snd_pcm_sw_params_set_start_threshold(ai->alsa.handle, swparams, 0);
  97     err = snd_pcm_sw_params_set_stop_threshold(ai->alsa.handle, swparams, buffer_size);
  98
  99     if (snd_pcm_sw_params(ai->alsa.handle, swparams) < 0) {
 100         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_CannotInstallSWParams);
 101         snd_pcm_sw_params_dump(swparams, ai->alsa.log);
 102         return -1;
 103     }
 104
 105     if (mp_msg_test(MSGT_TV, MSGL_V)) {
 106         snd_pcm_dump(ai->alsa.handle, ai->alsa.log);
 107     }
 108
 109     ai->alsa.bits_per_sample = snd_pcm_format_physical_width(SND_PCM_FORMAT_S16_LE);
 110     ai->alsa.bits_per_frame = ai->alsa.bits_per_sample * ai->channels;
 111     ai->blocksize = ai->alsa.chunk_size * ai->alsa.bits_per_frame / 8;
 112     ai->samplesize = ai->alsa.bits_per_sample;
 113     ai->bytes_per_sample = ai->alsa.bits_per_sample/8;
 114
 115     return 0;
 116 }
 117
 118 int ai_alsa_init(audio_in_t *ai)
 119 {
 120     int err;
 121
 122     err = snd_pcm_open(&ai->alsa.handle, ai->alsa.device, SND_PCM_STREAM_CAPTURE, 0);
 123     if (err < 0) {
 124         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_ErrorOpeningAudio, snd_strerror(err));
 125         return -1;
 126     }
 127
 128     err = snd_output_stdio_attach(&ai->alsa.log, stderr, 0);
 129
 130     if (err < 0) {
 131         return -1;
 132     }
 133
 134     err = ai_alsa_setup(ai);
 135
 136     return err;
 137 }
 138
 139 #ifndef timersub
 140 #define timersub(a, b, result) \
 141 do { \
 142         (result)->tv_sec = (a)->tv_sec - (b)->tv_sec; \
 143         (result)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
 144         if ((result)->tv_usec < 0) { \
 145                 --(result)->tv_sec; \
 146                 (result)->tv_usec += 1000000; \
 147         } \
 148 } while (0)
 149 #endif
 150
 151 int ai_alsa_xrun(audio_in_t *ai)
 152 {
 153     snd_pcm_status_t *status;
 154     int res;
 155
 156     snd_pcm_status_alloca(&status);
 157     if ((res = snd_pcm_status(ai->alsa.handle, status))<0) {
 158         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_AlsaStatusError, snd_strerror(res));
 159         return -1;
 160     }
 161     if (snd_pcm_status_get_state(status) == SND_PCM_STATE_XRUN) {
 162         struct timeval now, diff, tstamp;
 163         gettimeofday(&now, 0);
 164         snd_pcm_status_get_trigger_tstamp(status, &tstamp);
 165         timersub(&now, &tstamp, &diff);
 166         mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_AlsaXRUN,
 167                diff.tv_sec * 1000 + diff.tv_usec / 1000.0);
 168         if (mp_msg_test(MSGT_TV, MSGL_V)) {
 169             mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_AlsaStatus);
 170             snd_pcm_status_dump(status, ai->alsa.log);
 171         }
 172         if ((res = snd_pcm_prepare(ai->alsa.handle))<0) {
 173             mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_AlsaXRUNPrepareError, snd_strerror(res));
 174             return -1;
 175         }
 176         return 0;               /* ok, data should be accepted again */
 177     }
 178     mp_msg(MSGT_TV, MSGL_ERR, MSGTR_MPDEMUX_AIALSA_AlsaReadWriteError);
 179     return -1;
 180 }