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/* See LICENSE file for copyright and license details. */
#include "common.h"
#include <alsa/asoundlib.h>
#include <math.h>
/* TODO add support for online configuration */
/* TODO add support for displaying input note */
/* TODO add support for selecting output device and backend */
/* TODO add support for selecting volume */
/* TODO use bus to listen for incoming phone calls and pause when arriving */
#define UTYPE uint32_t
#define SMAX INT32_MAX
#define FORMAT SND_PCM_FORMAT_U32
#define SAMPLE_RATE 52000 /* Hz */
#define LATENCY 100000 /* µs */
USAGE("[-a | -u] [-n note] [-o octave]");
static int
check_n_lined(const char *s, const char *a, const char *b)
{
if (!strncmp(s, a, strlen(a)))
s = &s[strlen(a)];
else if (!strncmp(s, b, strlen(b)))
s = &s[strlen(b)];
else
return 0;
if (*s == '-' || *s == ' ')
s = &s[1];
else if (!strncmp(s, " ", strlen(" ")))
s = &s[strlen(" ")];
else
return 0;
return !strcasecmp(s, "lined");
}
int
main(int argc, char *argv[])
{
UTYPE *buffer;
snd_pcm_uframes_t i, buflen, wavelen;
snd_pcm_sframes_t n;
snd_pcm_t *sound_handle = NULL;
double freq = 440;
double volume = (double)0.1f, imul, omul, osub;
char *env, *note_str = NULL, *octave_str = NULL, *end;
int r, ascii, note, octave;
env = getenv("TERM");
ascii = (env && !strcmp(env, "linux"));
ARGBEGIN {
case 'a':
ascii = 1;
break;
case 'n':
if (note_str)
usage();
note_str = ARG();
break;
case 'o':
if (octave_str)
usage();
octave_str = ARG();
break;
case 'u':
ascii = 0;
break;
default:
usage();
} ARGEND;
if (argc)
usage();
if (!note_str) {
note = 9;
} else {
if (note_str[0] == 'C' || note_str[0] == 'c')
note = 0;
else if (note_str[0] == 'D' || note_str[0] == 'd')
note = 2;
else if (note_str[0] == 'E' || note_str[0] == 'e')
note = 4;
else if (note_str[0] == 'F' || note_str[0] == 'f')
note = 5;
else if (note_str[0] == 'G' || note_str[0] == 'g')
note = 7;
else if (note_str[0] == 'A' || note_str[0] == 'a')
note = 9;
else if (note_str[0] == 'B' || note_str[0] == 'b' || note_str[0] == 'H' || note_str[0] == 'h')
note = 11;
else
eprintf("%s is not a recognised note\n", note_str);
if (!strcmp(¬e_str[1], "#") || !strcmp(¬e_str[1], "♯"))
note += 1;
else if (!strcmp(¬e_str[1], "b") || !strcmp(¬e_str[1], "♭"))
note -= 1;
else if (note_str[1])
eprintf("%s is not a recognised note\n", note_str);
}
if (!octave_str) {
octave = 4;
} else if (!strcasecmp(octave_str, "subsubcontra")) {
octave = -1;
} else if (!strcasecmp(octave_str, "subcontra")) {
octave = 0;
} else if (!strcasecmp(octave_str, "contra")) {
octave = 1;
} else if (!strcasecmp(octave_str, "great")) {
octave = 2;
} else if (!strcasecmp(octave_str, "small")) {
octave = 3;
} else if (check_n_lined(octave_str, "one", "1")) {
octave = 4;
} else if (check_n_lined(octave_str, "two", "2")) {
octave = 5;
} else if (check_n_lined(octave_str, "three", "3")) {
octave = 6;
} else if (check_n_lined(octave_str, "four", "4")) {
octave = 7;
} else if (check_n_lined(octave_str, "five", "5")) {
octave = 8;
} else if (check_n_lined(octave_str, "six", "6")) {
octave = 9;
} else if (check_n_lined(octave_str, "seven", "7")) {
octave = 10;
} else if (!isdigit(octave_str[0]) && octave_str[0] != '-') {
eprintf("%s is not a recognised octave\n", note_str);
} else {
long int tmp;
errno = 0;
tmp = strtol(octave_str, &end, 10);
if (errno)
eprintf("strol %s:", octave_str);
if (*end)
eprintf("%s is not a recognised octave\n", note_str);
if (tmp < ((long int)INT_MIN + 1 + 9) / 12 + 4 ||
tmp > ((long int)INT_MAX - 12 + 9) / 12 + 4)
eprintf("octave %s is out side the supported domain\n", note_str);
octave = (int)tmp;
}
fprintf(stderr, "Note: %i\n", note);
fprintf(stderr, "Octave: %i\n", octave);
note += 12 * (octave - 4);
freq = 440 * pow(2, (double)(note - 9) / 12);
fprintf(stderr, "Frequency: %g Hz\n", freq);
fprintf(stderr, "Wavelength: %g mm\n", 343000 / freq);
/* Set up audio */
r = snd_pcm_open(&sound_handle, "default", SND_PCM_STREAM_PLAYBACK, 0);
if (r < 0)
eprintf("snd_pcm_open: %s\n", snd_strerror(r));
if (!sound_handle)
eprintf("snd_pcm_open:");
/* Configure audio */
r = snd_pcm_set_params(sound_handle, FORMAT, SND_PCM_ACCESS_RW_INTERLEAVED, 1 /* channels */,
SAMPLE_RATE, 1 /* allow resampling? */, LATENCY);
if (r < 0)
eprintf("snd_pcm_set_params: %s\n", snd_strerror(r));
/* Generate tone */
buflen = wavelen = (snd_pcm_uframes_t)((double)SAMPLE_RATE / freq);
if ((snd_pcm_uframes_t)freq > 1)
buflen *= (snd_pcm_uframes_t)freq;
buffer = emallocn((size_t)buflen, sizeof(*buffer), 0);
omul = volume * SMAX * 2;
#ifdef __GNUC__
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wunsuffixed-float-constants"
#endif
imul = 2 * M_PI * freq / (double)SAMPLE_RATE;
#ifdef __GNUC__
# pragma GCC diagnostic pop
#endif
for (i = 0; i < wavelen; i++)
buffer[i] = (UTYPE)(sin(imul * (double)i) * omul - osub);
for (i = wavelen; i < buflen; i += wavelen)
memcpy(&buffer[i], &buffer[0], wavelen * sizeof(UTYPE));
/* Play tone */
for (;;) {
n = snd_pcm_writei(sound_handle, buffer, buflen);
if (n < 0)
n = snd_pcm_recover(sound_handle, (int)n, 0 /* do not print error reason? */);
if (n < 0)
eprintf("snd_pcm_writei: %s\n", snd_strerror((int)n));
if (n > 0 && (snd_pcm_uframes_t)n < buflen)
eprintf("short write from snd_pcm_writei\n");
}
snd_pcm_close(sound_handle);
return 0;
}
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