code.delx.au - pulseaudio/blob - src/tests/alsa-time-test.c

   1 #include <assert.h>
   2 #include <inttypes.h>
   3 #include <time.h>
   4
   5 #include <alsa/asoundlib.h>
   6
   7 static uint64_t timespec_us(const struct timespec *ts) {
   8     return
   9         ts->tv_sec * 1000000LLU +
  10         ts->tv_nsec / 1000LLU;
  11 }
  12
  13 int main(int argc, char *argv[]) {
  14     const char *dev;
  15     int r;
  16     snd_pcm_hw_params_t *hwparams;
  17     snd_pcm_sw_params_t *swparams;
  18     snd_pcm_status_t *status;
  19     snd_pcm_t *pcm;
  20     unsigned rate = 44100;
  21     unsigned periods = 2;
  22     snd_pcm_uframes_t boundary, buffer_size = 44100/10; /* 100s */
  23     int dir = 1;
  24     struct timespec start, last_timestamp = { 0, 0 };
  25     uint64_t start_us;
  26     snd_pcm_sframes_t last_avail = 0, last_delay = 0;
  27     struct pollfd *pollfds;
  28     int n_pollfd;
  29     int64_t sample_count = 0;
  30
  31     snd_pcm_hw_params_alloca(&hwparams);
  32     snd_pcm_sw_params_alloca(&swparams);
  33     snd_pcm_status_alloca(&status);
  34
  35     r = clock_gettime(CLOCK_MONOTONIC, &start);
  36     assert(r == 0);
  37
  38     start_us = timespec_us(&start);
  39
  40     dev = argc > 1 ? argv[1] : "front:AudioPCI";
  41
  42     r = snd_pcm_open(&pcm, dev, SND_PCM_STREAM_PLAYBACK, 0);
  43     assert(r == 0);
  44
  45     r = snd_pcm_hw_params_any(pcm, hwparams);
  46     assert(r == 0);
  47
  48     r = snd_pcm_hw_params_set_rate_resample(pcm, hwparams, 0);
  49     assert(r == 0);
  50
  51     r = snd_pcm_hw_params_set_access(pcm, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED);
  52     assert(r == 0);
  53
  54     r = snd_pcm_hw_params_set_format(pcm, hwparams, SND_PCM_FORMAT_S16_LE);
  55     assert(r == 0);
  56
  57     r = snd_pcm_hw_params_set_rate_near(pcm, hwparams, &rate, NULL);
  58     assert(r == 0);
  59
  60     r = snd_pcm_hw_params_set_channels(pcm, hwparams, 2);
  61     assert(r == 0);
  62
  63     r = snd_pcm_hw_params_set_periods_integer(pcm, hwparams);
  64     assert(r == 0);
  65
  66     r = snd_pcm_hw_params_set_periods_near(pcm, hwparams, &periods, &dir);
  67     assert(r == 0);
  68
  69     r = snd_pcm_hw_params_set_buffer_size_near(pcm, hwparams, &buffer_size);
  70     assert(r == 0);
  71
  72     r = snd_pcm_hw_params(pcm, hwparams);
  73     assert(r == 0);
  74
  75     r = snd_pcm_hw_params_current(pcm, hwparams);
  76     assert(r == 0);
  77
  78     r = snd_pcm_sw_params_current(pcm, swparams);
  79     assert(r == 0);
  80
  81     r = snd_pcm_sw_params_set_avail_min(pcm, swparams, 1);
  82     assert(r == 0);
  83
  84     r = snd_pcm_sw_params_set_period_event(pcm, swparams, 0);
  85     assert(r == 0);
  86
  87     r = snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
  88     assert(r == 0);
  89     r = snd_pcm_sw_params_set_start_threshold(pcm, swparams, buffer_size);
  90     assert(r == 0);
  91
  92     r = snd_pcm_sw_params_get_boundary(swparams, &boundary);
  93     assert(r == 0);
  94     r = snd_pcm_sw_params_set_stop_threshold(pcm, swparams, boundary);
  95     assert(r == 0);
  96
  97     r = snd_pcm_sw_params_set_tstamp_mode(pcm, swparams, SND_PCM_TSTAMP_ENABLE);
  98     assert(r == 0);
  99
 100     r = snd_pcm_sw_params(pcm, swparams);
 101     assert(r == 0);
 102
 103     r = snd_pcm_prepare(pcm);
 104     assert(r == 0);
 105
 106     r = snd_pcm_sw_params_current(pcm, swparams);
 107     assert(r == 0);
 108
 109 /*     assert(snd_pcm_hw_params_is_monotonic(hwparams) > 0); */
 110
 111     n_pollfd = snd_pcm_poll_descriptors_count(pcm);
 112     assert(n_pollfd > 0);
 113
 114     pollfds = malloc(sizeof(struct pollfd) * n_pollfd);
 115     assert(pollfds);
 116
 117     r = snd_pcm_poll_descriptors(pcm, pollfds, n_pollfd);
 118     assert(r == n_pollfd);
 119
 120     for (;;) {
 121         snd_pcm_sframes_t avail, delay;
 122         struct timespec now, timestamp;
 123         unsigned short revents;
 124         int written = 0;
 125         uint64_t now_us, timestamp_us;
 126         snd_pcm_state_t state;
 127
 128         r = poll(pollfds, n_pollfd, 0);
 129         assert(r >= 0);
 130
 131         r = snd_pcm_poll_descriptors_revents(pcm, pollfds, n_pollfd, &revents);
 132         assert(r == 0);
 133
 134         assert((revents & ~POLLOUT) == 0);
 135
 136         avail = snd_pcm_avail(pcm);
 137         assert(avail >= 0);
 138
 139         r = snd_pcm_status(pcm, status);
 140         assert(r == 0);
 141
 142         /* This assertion fails from time to time. ALSA seems to be broken */
 143 /*         assert(avail == (snd_pcm_sframes_t) snd_pcm_status_get_avail(status)); */
 144 /*         printf("%lu %lu\n", (unsigned long) avail, (unsigned long) snd_pcm_status_get_avail(status)); */
 145
 146         snd_pcm_status_get_htstamp(status, &timestamp);
 147         delay = snd_pcm_status_get_delay(status);
 148         state = snd_pcm_status_get_state(status);
 149
 150         r = clock_gettime(CLOCK_MONOTONIC, &now);
 151         assert(r == 0);
 152
 153         assert(!revents || avail > 0);
 154
 155         if (avail) {
 156             snd_pcm_sframes_t sframes;
 157             static const uint16_t samples[2] = { 0, 0 };
 158
 159             sframes = snd_pcm_writei(pcm, samples, 1);
 160             assert(sframes == 1);
 161
 162             written = 1;
 163             sample_count++;
 164         }
 165
 166         if (!written &&
 167             memcmp(&timestamp, &last_timestamp, sizeof(timestamp)) == 0 &&
 168             avail == last_avail &&
 169             delay == last_delay) {
 170             /* This is boring */
 171             continue;
 172         }
 173
 174         now_us = timespec_us(&now);
 175         timestamp_us = timespec_us(&timestamp);
 176
 177         printf("%llu\t%llu\t%llu\t%li\t%li\t%i\t%i\t%i\n",
 178                (unsigned long long) (now_us - start_us),
 179                (unsigned long long) (timestamp_us ? timestamp_us - start_us : 0),
 180                (unsigned long long) ((sample_count - 1 - delay) * 1000000LU / 44100),
 181                (signed long) avail,
 182                (signed long) delay,
 183                revents,
 184                written,
 185                state);
 186
 187         /** When this assert is hit, most likely something bad
 188          * happened, i.e. the avail jumped suddenly. */
 189         assert((unsigned) avail <= buffer_size);
 190
 191         last_avail = avail;
 192         last_delay = delay;
 193         last_timestamp = timestamp;
 194     }
 195
 196     return 0;
 197 }