926 lines
25 KiB
C
926 lines
25 KiB
C
/*
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* This small demo sends a simple sinusoidal wave to your speakers.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sched.h>
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#include <errno.h>
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#include <getopt.h>
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#include "../include/asoundlib.h"
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#include <sys/time.h>
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#include <math.h>
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static char *device = "plughw:0,0"; /* playback device */
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static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */
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static unsigned int rate = 44100; /* stream rate */
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static unsigned int channels = 1; /* count of channels */
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static unsigned int buffer_time = 500000; /* ring buffer length in us */
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static unsigned int period_time = 100000; /* period time in us */
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static double freq = 440; /* sinusoidal wave frequency in Hz */
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static int verbose = 0; /* verbose flag */
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static int resample = 1; /* enable alsa-lib resampling */
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static int period_event = 0; /* produce poll event after each period */
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static snd_pcm_sframes_t buffer_size;
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static snd_pcm_sframes_t period_size;
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static snd_output_t *output = NULL;
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static void generate_sine(const snd_pcm_channel_area_t *areas,
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snd_pcm_uframes_t offset,
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int count, double *_phase)
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{
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static double max_phase = 2. * M_PI;
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double phase = *_phase;
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double step = max_phase*freq/(double)rate;
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unsigned char *samples[channels];
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int steps[channels];
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unsigned int chn;
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int format_bits = snd_pcm_format_width(format);
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unsigned int maxval = (1 << (format_bits - 1)) - 1;
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int bps = format_bits / 8; /* bytes per sample */
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int phys_bps = snd_pcm_format_physical_width(format) / 8;
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int big_endian = snd_pcm_format_big_endian(format) == 1;
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int to_unsigned = snd_pcm_format_unsigned(format) == 1;
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int is_float = (format == SND_PCM_FORMAT_FLOAT_LE ||
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format == SND_PCM_FORMAT_FLOAT_BE);
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/* verify and prepare the contents of areas */
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for (chn = 0; chn < channels; chn++) {
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if ((areas[chn].first % 8) != 0) {
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printf("areas[%i].first == %i, aborting...\n", chn, areas[chn].first);
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exit(EXIT_FAILURE);
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}
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samples[chn] = /*(signed short *)*/(((unsigned char *)areas[chn].addr) + (areas[chn].first / 8));
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if ((areas[chn].step % 16) != 0) {
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printf("areas[%i].step == %i, aborting...\n", chn, areas[chn].step);
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exit(EXIT_FAILURE);
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}
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steps[chn] = areas[chn].step / 8;
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samples[chn] += offset * steps[chn];
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}
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/* fill the channel areas */
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while (count-- > 0) {
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union {
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float f;
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int i;
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} fval;
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int res, i;
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if (is_float) {
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fval.f = sin(phase) * maxval;
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res = fval.i;
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} else
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res = sin(phase) * maxval;
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if (to_unsigned)
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res ^= 1U << (format_bits - 1);
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for (chn = 0; chn < channels; chn++) {
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/* Generate data in native endian format */
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if (big_endian) {
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for (i = 0; i < bps; i++)
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*(samples[chn] + phys_bps - 1 - i) = (res >> i * 8) & 0xff;
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} else {
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for (i = 0; i < bps; i++)
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*(samples[chn] + i) = (res >> i * 8) & 0xff;
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}
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samples[chn] += steps[chn];
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}
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phase += step;
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if (phase >= max_phase)
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phase -= max_phase;
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}
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*_phase = phase;
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}
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static int set_hwparams(snd_pcm_t *handle,
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snd_pcm_hw_params_t *params,
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snd_pcm_access_t access)
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{
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unsigned int rrate;
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snd_pcm_uframes_t size;
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int err, dir;
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/* choose all parameters */
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err = snd_pcm_hw_params_any(handle, params);
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if (err < 0) {
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printf("Broken configuration for playback: no configurations available: %s\n", snd_strerror(err));
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return err;
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}
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/* set hardware resampling */
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err = snd_pcm_hw_params_set_rate_resample(handle, params, resample);
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if (err < 0) {
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printf("Resampling setup failed for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* set the interleaved read/write format */
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err = snd_pcm_hw_params_set_access(handle, params, access);
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if (err < 0) {
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printf("Access type not available for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* set the sample format */
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err = snd_pcm_hw_params_set_format(handle, params, format);
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if (err < 0) {
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printf("Sample format not available for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* set the count of channels */
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err = snd_pcm_hw_params_set_channels(handle, params, channels);
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if (err < 0) {
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printf("Channels count (%i) not available for playbacks: %s\n", channels, snd_strerror(err));
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return err;
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}
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/* set the stream rate */
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rrate = rate;
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err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0);
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if (err < 0) {
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printf("Rate %iHz not available for playback: %s\n", rate, snd_strerror(err));
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return err;
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}
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if (rrate != rate) {
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printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err);
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return -EINVAL;
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}
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/* set the buffer time */
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err = snd_pcm_hw_params_set_buffer_time_near(handle, params, &buffer_time, &dir);
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if (err < 0) {
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printf("Unable to set buffer time %i for playback: %s\n", buffer_time, snd_strerror(err));
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return err;
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}
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err = snd_pcm_hw_params_get_buffer_size(params, &size);
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if (err < 0) {
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printf("Unable to get buffer size for playback: %s\n", snd_strerror(err));
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return err;
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}
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buffer_size = size;
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/* set the period time */
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err = snd_pcm_hw_params_set_period_time_near(handle, params, &period_time, &dir);
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if (err < 0) {
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printf("Unable to set period time %i for playback: %s\n", period_time, snd_strerror(err));
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return err;
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}
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err = snd_pcm_hw_params_get_period_size(params, &size, &dir);
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if (err < 0) {
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printf("Unable to get period size for playback: %s\n", snd_strerror(err));
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return err;
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}
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period_size = size;
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/* write the parameters to device */
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err = snd_pcm_hw_params(handle, params);
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if (err < 0) {
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printf("Unable to set hw params for playback: %s\n", snd_strerror(err));
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return err;
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}
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return 0;
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}
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static int set_swparams(snd_pcm_t *handle, snd_pcm_sw_params_t *swparams)
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{
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int err;
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/* get the current swparams */
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err = snd_pcm_sw_params_current(handle, swparams);
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if (err < 0) {
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printf("Unable to determine current swparams for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* start the transfer when the buffer is almost full: */
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/* (buffer_size / avail_min) * avail_min */
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err = snd_pcm_sw_params_set_start_threshold(handle, swparams, (buffer_size / period_size) * period_size);
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if (err < 0) {
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printf("Unable to set start threshold mode for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* allow the transfer when at least period_size samples can be processed */
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/* or disable this mechanism when period event is enabled (aka interrupt like style processing) */
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err = snd_pcm_sw_params_set_avail_min(handle, swparams, period_event ? buffer_size : period_size);
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if (err < 0) {
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printf("Unable to set avail min for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* enable period events when requested */
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if (period_event) {
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err = snd_pcm_sw_params_set_period_event(handle, swparams, 1);
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if (err < 0) {
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printf("Unable to set period event: %s\n", snd_strerror(err));
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return err;
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}
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}
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/* write the parameters to the playback device */
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err = snd_pcm_sw_params(handle, swparams);
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if (err < 0) {
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printf("Unable to set sw params for playback: %s\n", snd_strerror(err));
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return err;
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}
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return 0;
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}
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/*
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* Underrun and suspend recovery
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*/
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static int xrun_recovery(snd_pcm_t *handle, int err)
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{
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if (verbose)
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printf("stream recovery\n");
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if (err == -EPIPE) { /* under-run */
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err = snd_pcm_prepare(handle);
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if (err < 0)
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printf("Can't recovery from underrun, prepare failed: %s\n", snd_strerror(err));
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return 0;
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} else if (err == -ESTRPIPE) {
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while ((err = snd_pcm_resume(handle)) == -EAGAIN)
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sleep(1); /* wait until the suspend flag is released */
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if (err < 0) {
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err = snd_pcm_prepare(handle);
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if (err < 0)
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printf("Can't recovery from suspend, prepare failed: %s\n", snd_strerror(err));
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}
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return 0;
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}
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return err;
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}
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/*
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* Transfer method - write only
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*/
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static int write_loop(snd_pcm_t *handle,
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signed short *samples,
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snd_pcm_channel_area_t *areas)
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{
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double phase = 0;
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signed short *ptr;
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int err, cptr;
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while (1) {
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generate_sine(areas, 0, period_size, &phase);
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ptr = samples;
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cptr = period_size;
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while (cptr > 0) {
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err = snd_pcm_writei(handle, ptr, cptr);
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if (err == -EAGAIN)
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continue;
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if (err < 0) {
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if (xrun_recovery(handle, err) < 0) {
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printf("Write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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break; /* skip one period */
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}
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ptr += err * channels;
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cptr -= err;
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}
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}
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}
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/*
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* Transfer method - write and wait for room in buffer using poll
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*/
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static int wait_for_poll(snd_pcm_t *handle, struct pollfd *ufds, unsigned int count)
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{
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unsigned short revents;
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while (1) {
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poll(ufds, count, -1);
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snd_pcm_poll_descriptors_revents(handle, ufds, count, &revents);
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if (revents & POLLERR)
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return -EIO;
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if (revents & POLLOUT)
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return 0;
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}
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}
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static int write_and_poll_loop(snd_pcm_t *handle,
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signed short *samples,
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snd_pcm_channel_area_t *areas)
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{
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struct pollfd *ufds;
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double phase = 0;
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signed short *ptr;
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int err, count, cptr, init;
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count = snd_pcm_poll_descriptors_count (handle);
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if (count <= 0) {
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printf("Invalid poll descriptors count\n");
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return count;
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}
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ufds = malloc(sizeof(struct pollfd) * count);
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if (ufds == NULL) {
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printf("No enough memory\n");
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return -ENOMEM;
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}
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if ((err = snd_pcm_poll_descriptors(handle, ufds, count)) < 0) {
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printf("Unable to obtain poll descriptors for playback: %s\n", snd_strerror(err));
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return err;
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}
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init = 1;
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while (1) {
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if (!init) {
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err = wait_for_poll(handle, ufds, count);
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if (err < 0) {
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if (snd_pcm_state(handle) == SND_PCM_STATE_XRUN ||
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snd_pcm_state(handle) == SND_PCM_STATE_SUSPENDED) {
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err = snd_pcm_state(handle) == SND_PCM_STATE_XRUN ? -EPIPE : -ESTRPIPE;
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if (xrun_recovery(handle, err) < 0) {
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printf("Write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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init = 1;
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} else {
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printf("Wait for poll failed\n");
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return err;
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}
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}
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}
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generate_sine(areas, 0, period_size, &phase);
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ptr = samples;
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cptr = period_size;
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while (cptr > 0) {
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err = snd_pcm_writei(handle, ptr, cptr);
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if (err < 0) {
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if (xrun_recovery(handle, err) < 0) {
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printf("Write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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init = 1;
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break; /* skip one period */
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}
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if (snd_pcm_state(handle) == SND_PCM_STATE_RUNNING)
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init = 0;
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ptr += err * channels;
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cptr -= err;
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if (cptr == 0)
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break;
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/* it is possible, that the initial buffer cannot store */
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/* all data from the last period, so wait awhile */
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err = wait_for_poll(handle, ufds, count);
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if (err < 0) {
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if (snd_pcm_state(handle) == SND_PCM_STATE_XRUN ||
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snd_pcm_state(handle) == SND_PCM_STATE_SUSPENDED) {
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err = snd_pcm_state(handle) == SND_PCM_STATE_XRUN ? -EPIPE : -ESTRPIPE;
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if (xrun_recovery(handle, err) < 0) {
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printf("Write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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init = 1;
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} else {
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printf("Wait for poll failed\n");
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return err;
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}
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}
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}
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}
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}
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/*
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* Transfer method - asynchronous notification
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*/
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struct async_private_data {
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signed short *samples;
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snd_pcm_channel_area_t *areas;
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double phase;
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};
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static void async_callback(snd_async_handler_t *ahandler)
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{
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snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
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struct async_private_data *data = snd_async_handler_get_callback_private(ahandler);
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signed short *samples = data->samples;
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snd_pcm_channel_area_t *areas = data->areas;
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snd_pcm_sframes_t avail;
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int err;
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avail = snd_pcm_avail_update(handle);
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while (avail >= period_size) {
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generate_sine(areas, 0, period_size, &data->phase);
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err = snd_pcm_writei(handle, samples, period_size);
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if (err < 0) {
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printf("Write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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if (err != period_size) {
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printf("Write error: written %i expected %li\n", err, period_size);
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exit(EXIT_FAILURE);
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}
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avail = snd_pcm_avail_update(handle);
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}
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}
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static int async_loop(snd_pcm_t *handle,
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signed short *samples,
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snd_pcm_channel_area_t *areas)
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{
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struct async_private_data data;
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snd_async_handler_t *ahandler;
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int err, count;
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data.samples = samples;
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data.areas = areas;
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data.phase = 0;
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err = snd_async_add_pcm_handler(&ahandler, handle, async_callback, &data);
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if (err < 0) {
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printf("Unable to register async handler\n");
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exit(EXIT_FAILURE);
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}
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for (count = 0; count < 2; count++) {
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generate_sine(areas, 0, period_size, &data.phase);
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err = snd_pcm_writei(handle, samples, period_size);
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if (err < 0) {
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printf("Initial write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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if (err != period_size) {
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printf("Initial write error: written %i expected %li\n", err, period_size);
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exit(EXIT_FAILURE);
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}
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}
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if (snd_pcm_state(handle) == SND_PCM_STATE_PREPARED) {
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err = snd_pcm_start(handle);
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if (err < 0) {
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printf("Start error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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}
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/* because all other work is done in the signal handler,
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suspend the process */
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while (1) {
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sleep(1);
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}
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}
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/*
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* Transfer method - asynchronous notification + direct write
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*/
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static void async_direct_callback(snd_async_handler_t *ahandler)
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{
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snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
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struct async_private_data *data = snd_async_handler_get_callback_private(ahandler);
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const snd_pcm_channel_area_t *my_areas;
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snd_pcm_uframes_t offset, frames, size;
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snd_pcm_sframes_t avail, commitres;
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snd_pcm_state_t state;
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int first = 0, err;
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while (1) {
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state = snd_pcm_state(handle);
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if (state == SND_PCM_STATE_XRUN) {
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err = xrun_recovery(handle, -EPIPE);
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if (err < 0) {
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printf("XRUN recovery failed: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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first = 1;
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} else if (state == SND_PCM_STATE_SUSPENDED) {
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err = xrun_recovery(handle, -ESTRPIPE);
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if (err < 0) {
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printf("SUSPEND recovery failed: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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}
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avail = snd_pcm_avail_update(handle);
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if (avail < 0) {
|
|
err = xrun_recovery(handle, avail);
|
|
if (err < 0) {
|
|
printf("avail update failed: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
first = 1;
|
|
continue;
|
|
}
|
|
if (avail < period_size) {
|
|
if (first) {
|
|
first = 0;
|
|
err = snd_pcm_start(handle);
|
|
if (err < 0) {
|
|
printf("Start error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
continue;
|
|
}
|
|
size = period_size;
|
|
while (size > 0) {
|
|
frames = size;
|
|
err = snd_pcm_mmap_begin(handle, &my_areas, &offset, &frames);
|
|
if (err < 0) {
|
|
if ((err = xrun_recovery(handle, err)) < 0) {
|
|
printf("MMAP begin avail error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
first = 1;
|
|
}
|
|
generate_sine(my_areas, offset, frames, &data->phase);
|
|
commitres = snd_pcm_mmap_commit(handle, offset, frames);
|
|
if (commitres < 0 || (snd_pcm_uframes_t)commitres != frames) {
|
|
if ((err = xrun_recovery(handle, commitres >= 0 ? -EPIPE : commitres)) < 0) {
|
|
printf("MMAP commit error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
first = 1;
|
|
}
|
|
size -= frames;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int async_direct_loop(snd_pcm_t *handle,
|
|
signed short *samples ATTRIBUTE_UNUSED,
|
|
snd_pcm_channel_area_t *areas ATTRIBUTE_UNUSED)
|
|
{
|
|
struct async_private_data data;
|
|
snd_async_handler_t *ahandler;
|
|
const snd_pcm_channel_area_t *my_areas;
|
|
snd_pcm_uframes_t offset, frames, size;
|
|
snd_pcm_sframes_t commitres;
|
|
int err, count;
|
|
|
|
data.samples = NULL; /* we do not require the global sample area for direct write */
|
|
data.areas = NULL; /* we do not require the global areas for direct write */
|
|
data.phase = 0;
|
|
err = snd_async_add_pcm_handler(&ahandler, handle, async_direct_callback, &data);
|
|
if (err < 0) {
|
|
printf("Unable to register async handler\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
for (count = 0; count < 2; count++) {
|
|
size = period_size;
|
|
while (size > 0) {
|
|
frames = size;
|
|
err = snd_pcm_mmap_begin(handle, &my_areas, &offset, &frames);
|
|
if (err < 0) {
|
|
if ((err = xrun_recovery(handle, err)) < 0) {
|
|
printf("MMAP begin avail error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
}
|
|
generate_sine(my_areas, offset, frames, &data.phase);
|
|
commitres = snd_pcm_mmap_commit(handle, offset, frames);
|
|
if (commitres < 0 || (snd_pcm_uframes_t)commitres != frames) {
|
|
if ((err = xrun_recovery(handle, commitres >= 0 ? -EPIPE : commitres)) < 0) {
|
|
printf("MMAP commit error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
}
|
|
size -= frames;
|
|
}
|
|
}
|
|
err = snd_pcm_start(handle);
|
|
if (err < 0) {
|
|
printf("Start error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* because all other work is done in the signal handler,
|
|
suspend the process */
|
|
while (1) {
|
|
sleep(1);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Transfer method - direct write only
|
|
*/
|
|
|
|
static int direct_loop(snd_pcm_t *handle,
|
|
signed short *samples ATTRIBUTE_UNUSED,
|
|
snd_pcm_channel_area_t *areas ATTRIBUTE_UNUSED)
|
|
{
|
|
double phase = 0;
|
|
const snd_pcm_channel_area_t *my_areas;
|
|
snd_pcm_uframes_t offset, frames, size;
|
|
snd_pcm_sframes_t avail, commitres;
|
|
snd_pcm_state_t state;
|
|
int err, first = 1;
|
|
|
|
while (1) {
|
|
state = snd_pcm_state(handle);
|
|
if (state == SND_PCM_STATE_XRUN) {
|
|
err = xrun_recovery(handle, -EPIPE);
|
|
if (err < 0) {
|
|
printf("XRUN recovery failed: %s\n", snd_strerror(err));
|
|
return err;
|
|
}
|
|
first = 1;
|
|
} else if (state == SND_PCM_STATE_SUSPENDED) {
|
|
err = xrun_recovery(handle, -ESTRPIPE);
|
|
if (err < 0) {
|
|
printf("SUSPEND recovery failed: %s\n", snd_strerror(err));
|
|
return err;
|
|
}
|
|
}
|
|
avail = snd_pcm_avail_update(handle);
|
|
if (avail < 0) {
|
|
err = xrun_recovery(handle, avail);
|
|
if (err < 0) {
|
|
printf("avail update failed: %s\n", snd_strerror(err));
|
|
return err;
|
|
}
|
|
first = 1;
|
|
continue;
|
|
}
|
|
if (avail < period_size) {
|
|
if (first) {
|
|
first = 0;
|
|
err = snd_pcm_start(handle);
|
|
if (err < 0) {
|
|
printf("Start error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
} else {
|
|
err = snd_pcm_wait(handle, -1);
|
|
if (err < 0) {
|
|
if ((err = xrun_recovery(handle, err)) < 0) {
|
|
printf("snd_pcm_wait error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
first = 1;
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
size = period_size;
|
|
while (size > 0) {
|
|
frames = size;
|
|
err = snd_pcm_mmap_begin(handle, &my_areas, &offset, &frames);
|
|
if (err < 0) {
|
|
if ((err = xrun_recovery(handle, err)) < 0) {
|
|
printf("MMAP begin avail error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
first = 1;
|
|
}
|
|
generate_sine(my_areas, offset, frames, &phase);
|
|
commitres = snd_pcm_mmap_commit(handle, offset, frames);
|
|
if (commitres < 0 || (snd_pcm_uframes_t)commitres != frames) {
|
|
if ((err = xrun_recovery(handle, commitres >= 0 ? -EPIPE : commitres)) < 0) {
|
|
printf("MMAP commit error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
first = 1;
|
|
}
|
|
size -= frames;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Transfer method - direct write only using mmap_write functions
|
|
*/
|
|
|
|
static int direct_write_loop(snd_pcm_t *handle,
|
|
signed short *samples,
|
|
snd_pcm_channel_area_t *areas)
|
|
{
|
|
double phase = 0;
|
|
signed short *ptr;
|
|
int err, cptr;
|
|
|
|
while (1) {
|
|
generate_sine(areas, 0, period_size, &phase);
|
|
ptr = samples;
|
|
cptr = period_size;
|
|
while (cptr > 0) {
|
|
err = snd_pcm_mmap_writei(handle, ptr, cptr);
|
|
if (err == -EAGAIN)
|
|
continue;
|
|
if (err < 0) {
|
|
if (xrun_recovery(handle, err) < 0) {
|
|
printf("Write error: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
break; /* skip one period */
|
|
}
|
|
ptr += err * channels;
|
|
cptr -= err;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
*
|
|
*/
|
|
|
|
struct transfer_method {
|
|
const char *name;
|
|
snd_pcm_access_t access;
|
|
int (*transfer_loop)(snd_pcm_t *handle,
|
|
signed short *samples,
|
|
snd_pcm_channel_area_t *areas);
|
|
};
|
|
|
|
static struct transfer_method transfer_methods[] = {
|
|
{ "write", SND_PCM_ACCESS_RW_INTERLEAVED, write_loop },
|
|
{ "write_and_poll", SND_PCM_ACCESS_RW_INTERLEAVED, write_and_poll_loop },
|
|
{ "async", SND_PCM_ACCESS_RW_INTERLEAVED, async_loop },
|
|
{ "async_direct", SND_PCM_ACCESS_MMAP_INTERLEAVED, async_direct_loop },
|
|
{ "direct_interleaved", SND_PCM_ACCESS_MMAP_INTERLEAVED, direct_loop },
|
|
{ "direct_noninterleaved", SND_PCM_ACCESS_MMAP_NONINTERLEAVED, direct_loop },
|
|
{ "direct_write", SND_PCM_ACCESS_MMAP_INTERLEAVED, direct_write_loop },
|
|
{ NULL, SND_PCM_ACCESS_RW_INTERLEAVED, NULL }
|
|
};
|
|
|
|
static void help(void)
|
|
{
|
|
int k;
|
|
printf(
|
|
"Usage: pcm [OPTION]... [FILE]...\n"
|
|
"-h,--help help\n"
|
|
"-D,--device playback device\n"
|
|
"-r,--rate stream rate in Hz\n"
|
|
"-c,--channels count of channels in stream\n"
|
|
"-f,--frequency sine wave frequency in Hz\n"
|
|
"-b,--buffer ring buffer size in us\n"
|
|
"-p,--period period size in us\n"
|
|
"-m,--method transfer method\n"
|
|
"-o,--format sample format\n"
|
|
"-v,--verbose show the PCM setup parameters\n"
|
|
"-n,--noresample do not resample\n"
|
|
"-e,--pevent enable poll event after each period\n"
|
|
"\n");
|
|
printf("Recognized sample formats are:");
|
|
for (k = 0; k < SND_PCM_FORMAT_LAST; ++k) {
|
|
const char *s = snd_pcm_format_name(k);
|
|
if (s)
|
|
printf(" %s", s);
|
|
}
|
|
printf("\n");
|
|
printf("Recognized transfer methods are:");
|
|
for (k = 0; transfer_methods[k].name; k++)
|
|
printf(" %s", transfer_methods[k].name);
|
|
printf("\n");
|
|
}
|
|
|
|
int main(int argc, char *argv[])
|
|
{
|
|
struct option long_option[] =
|
|
{
|
|
{"help", 0, NULL, 'h'},
|
|
{"device", 1, NULL, 'D'},
|
|
{"rate", 1, NULL, 'r'},
|
|
{"channels", 1, NULL, 'c'},
|
|
{"frequency", 1, NULL, 'f'},
|
|
{"buffer", 1, NULL, 'b'},
|
|
{"period", 1, NULL, 'p'},
|
|
{"method", 1, NULL, 'm'},
|
|
{"format", 1, NULL, 'o'},
|
|
{"verbose", 1, NULL, 'v'},
|
|
{"noresample", 1, NULL, 'n'},
|
|
{"pevent", 1, NULL, 'e'},
|
|
{NULL, 0, NULL, 0},
|
|
};
|
|
snd_pcm_t *handle;
|
|
int err, morehelp;
|
|
snd_pcm_hw_params_t *hwparams;
|
|
snd_pcm_sw_params_t *swparams;
|
|
int method = 0;
|
|
signed short *samples;
|
|
unsigned int chn;
|
|
snd_pcm_channel_area_t *areas;
|
|
|
|
snd_pcm_hw_params_alloca(&hwparams);
|
|
snd_pcm_sw_params_alloca(&swparams);
|
|
|
|
morehelp = 0;
|
|
while (1) {
|
|
int c;
|
|
if ((c = getopt_long(argc, argv, "hD:r:c:f:b:p:m:o:vne", long_option, NULL)) < 0)
|
|
break;
|
|
switch (c) {
|
|
case 'h':
|
|
morehelp++;
|
|
break;
|
|
case 'D':
|
|
device = strdup(optarg);
|
|
break;
|
|
case 'r':
|
|
rate = atoi(optarg);
|
|
rate = rate < 4000 ? 4000 : rate;
|
|
rate = rate > 196000 ? 196000 : rate;
|
|
break;
|
|
case 'c':
|
|
channels = atoi(optarg);
|
|
channels = channels < 1 ? 1 : channels;
|
|
channels = channels > 1024 ? 1024 : channels;
|
|
break;
|
|
case 'f':
|
|
freq = atoi(optarg);
|
|
freq = freq < 50 ? 50 : freq;
|
|
freq = freq > 5000 ? 5000 : freq;
|
|
break;
|
|
case 'b':
|
|
buffer_time = atoi(optarg);
|
|
buffer_time = buffer_time < 1000 ? 1000 : buffer_time;
|
|
buffer_time = buffer_time > 1000000 ? 1000000 : buffer_time;
|
|
break;
|
|
case 'p':
|
|
period_time = atoi(optarg);
|
|
period_time = period_time < 1000 ? 1000 : period_time;
|
|
period_time = period_time > 1000000 ? 1000000 : period_time;
|
|
break;
|
|
case 'm':
|
|
for (method = 0; transfer_methods[method].name; method++)
|
|
if (!strcasecmp(transfer_methods[method].name, optarg))
|
|
break;
|
|
if (transfer_methods[method].name == NULL)
|
|
method = 0;
|
|
break;
|
|
case 'o':
|
|
for (format = 0; format < SND_PCM_FORMAT_LAST; format++) {
|
|
const char *format_name = snd_pcm_format_name(format);
|
|
if (format_name)
|
|
if (!strcasecmp(format_name, optarg))
|
|
break;
|
|
}
|
|
if (format == SND_PCM_FORMAT_LAST)
|
|
format = SND_PCM_FORMAT_S16;
|
|
if (!snd_pcm_format_linear(format) &&
|
|
!(format == SND_PCM_FORMAT_FLOAT_LE ||
|
|
format == SND_PCM_FORMAT_FLOAT_BE)) {
|
|
printf("Invalid (non-linear/float) format %s\n",
|
|
optarg);
|
|
return 1;
|
|
}
|
|
break;
|
|
case 'v':
|
|
verbose = 1;
|
|
break;
|
|
case 'n':
|
|
resample = 0;
|
|
break;
|
|
case 'e':
|
|
period_event = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (morehelp) {
|
|
help();
|
|
return 0;
|
|
}
|
|
|
|
err = snd_output_stdio_attach(&output, stdout, 0);
|
|
if (err < 0) {
|
|
printf("Output failed: %s\n", snd_strerror(err));
|
|
return 0;
|
|
}
|
|
|
|
printf("Playback device is %s\n", device);
|
|
printf("Stream parameters are %iHz, %s, %i channels\n", rate, snd_pcm_format_name(format), channels);
|
|
printf("Sine wave rate is %.4fHz\n", freq);
|
|
printf("Using transfer method: %s\n", transfer_methods[method].name);
|
|
|
|
if ((err = snd_pcm_open(&handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
|
|
printf("Playback open error: %s\n", snd_strerror(err));
|
|
return 0;
|
|
}
|
|
|
|
if ((err = set_hwparams(handle, hwparams, transfer_methods[method].access)) < 0) {
|
|
printf("Setting of hwparams failed: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
if ((err = set_swparams(handle, swparams)) < 0) {
|
|
printf("Setting of swparams failed: %s\n", snd_strerror(err));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
if (verbose > 0)
|
|
snd_pcm_dump(handle, output);
|
|
|
|
samples = malloc((period_size * channels * snd_pcm_format_physical_width(format)) / 8);
|
|
if (samples == NULL) {
|
|
printf("No enough memory\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
areas = calloc(channels, sizeof(snd_pcm_channel_area_t));
|
|
if (areas == NULL) {
|
|
printf("No enough memory\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
for (chn = 0; chn < channels; chn++) {
|
|
areas[chn].addr = samples;
|
|
areas[chn].first = chn * snd_pcm_format_physical_width(format);
|
|
areas[chn].step = channels * snd_pcm_format_physical_width(format);
|
|
}
|
|
|
|
err = transfer_methods[method].transfer_loop(handle, samples, areas);
|
|
if (err < 0)
|
|
printf("Transfer failed: %s\n", snd_strerror(err));
|
|
|
|
free(areas);
|
|
free(samples);
|
|
snd_pcm_close(handle);
|
|
return 0;
|
|
}
|
|
|