int
ToneAlarm::write(file *filp, const char *buffer, size_t len)
{
// sanity-check the buffer for length and nul-termination
if (len > _tune_max)
return -EFBIG;
// if we have an existing user tune, free it
if (_user_tune != nullptr) {
// if we are playing the user tune, stop
if (_tune == _user_tune) {
_tune = nullptr;
_next = nullptr;
}
// free the old user tune
free((void *)_user_tune);
_user_tune = nullptr;
}
// if the new tune is empty, we're done
if (buffer[0] == '\0')
return OK;
// allocate a copy of the new tune
_user_tune = strndup(buffer, len);
if (_user_tune == nullptr)
return -ENOMEM;
// and play it
start_tune(_user_tune);
return len;
}
int
ToneAlarm::ioctl(file *filp, int cmd, unsigned long arg)
{
int result = OK;
DEVICE_DEBUG("ioctl %i %u", cmd, arg);
// irqstate_t flags = enter_critical_section();
/* decide whether to increase the alarm level to cmd or leave it alone */
switch (cmd) {
case TONE_SET_ALARM:
DEVICE_DEBUG("TONE_SET_ALARM %u", arg);
if (arg < TONE_NUMBER_OF_TUNES) {
if (arg == TONE_STOP_TUNE) {
// stop the tune
_tune = nullptr;
_next = nullptr;
_repeat = false;
_default_tune_number = 0;
} else {
/* always interrupt alarms, unless they are repeating and already playing */
if (!(_repeat && _default_tune_number == arg)) {
/* play the selected tune */
_default_tune_number = arg;
start_tune(_default_tunes[arg]);
}
}
} else {
result = -EINVAL;
}
break;
default:
result = -ENOTTY;
break;
}
// leave_critical_section(flags);
/* give it to the superclass if we didn't like it */
if (result == -ENOTTY) {
result = CDev::ioctl(filp, cmd, arg);
}
return result;
}
void
ToneAlarm::next_note()
{
// do we have an inter-note gap to wait for?
if (_silence_length > 0) {
stop_note();
hrt_call_after(&_note_call, (hrt_abstime)_silence_length, (hrt_callout)next_trampoline, this);
_silence_length = 0;
return;
}
// make sure we still have a tune - may be removed by the write / ioctl handler
if ((_next == nullptr) || (_tune == nullptr)) {
stop_note();
return;
}
// parse characters out of the string until we have resolved a note
unsigned note = 0;
unsigned note_length = _note_length;
unsigned duration;
while (note == 0) {
// we always need at least one character from the string
int c = next_char();
if (c == 0) {
goto tune_end;
}
_next++;
switch (c) {
case 'L': // select note length
_note_length = next_number();
if (_note_length < 1) {
goto tune_error;
}
break;
case 'O': // select octave
_octave = next_number();
if (_octave > 6) {
_octave = 6;
}
break;
case '<': // decrease octave
if (_octave > 0) {
_octave--;
}
break;
case '>': // increase octave
if (_octave < 6) {
_octave++;
}
break;
case 'M': // select inter-note gap
c = next_char();
if (c == 0) {
goto tune_error;
}
_next++;
switch (c) {
case 'N':
_note_mode = MODE_NORMAL;
break;
case 'L':
_note_mode = MODE_LEGATO;
break;
case 'S':
_note_mode = MODE_STACCATO;
break;
case 'F':
_repeat = false;
break;
case 'B':
_repeat = true;
break;
default:
goto tune_error;
}
break;
case 'P': // pause for a note length
stop_note();
hrt_call_after(&_note_call,
(hrt_abstime)rest_duration(next_number(), next_dots()),
(hrt_callout)next_trampoline,
this);
return;
case 'T': { // change tempo
unsigned nt = next_number();
if ((nt >= 32) && (nt <= 255)) {
_tempo = nt;
} else {
goto tune_error;
}
break;
}
case 'N': // play an arbitrary note
note = next_number();
if (note > 84) {
goto tune_error;
}
if (note == 0) {
// this is a rest - pause for the current note length
hrt_call_after(&_note_call,
(hrt_abstime)rest_duration(_note_length, next_dots()),
(hrt_callout)next_trampoline,
this);
return;
}
break;
case 'A'...'G': // play a note in the current octave
note = _note_tab[c - 'A'] + (_octave * 12) + 1;
c = next_char();
switch (c) {
case '#': // up a semitone
case '+':
if (note < 84) {
note++;
}
_next++;
break;
case '-': // down a semitone
if (note > 1) {
note--;
}
_next++;
break;
default:
// 0 / no next char here is OK
break;
}
// shorthand length notation
note_length = next_number();
if (note_length == 0) {
note_length = _note_length;
}
break;
default:
goto tune_error;
}
}
// compute the duration of the note and the following silence (if any)
duration = note_duration(_silence_length, note_length, next_dots());
// start playing the note
start_note(note);
// and arrange a callback when the note should stop
hrt_call_after(&_note_call, (hrt_abstime)duration, (hrt_callout)next_trampoline, this);
return;
// tune looks bad (unexpected EOF, bad character, etc.)
tune_error:
syslog(LOG_ERR, "tune error\n");
_repeat = false; // don't loop on error
// stop (and potentially restart) the tune
tune_end:
stop_note();
if (_repeat) {
start_tune(_tune);
} else {
_tune = nullptr;
_default_tune_number = 0;
}
return;
}
