// thread pin control routine, does timed PWM to control brightness and pulsing
void *flasher(void *pptr)
{
bool waxing = true;
pin_t *pin = (pin_t*)pptr;
daemonLog("started thread for pin %d\n",pin->pin);
while(keepRunning) // each run of the loop should take one duty cycle... i.e. 100Hz
{
if (!pin->flashPeriod && pin->brightness<FLT_EPSILON) {
usleep(dutyCycle);
if (pin->powerOn) {
GPIO_SET = 1 << pin->pin;
} else {
GPIO_CLR = 1 << pin->pin;
}
} else {
useconds_t flashRate = pin->flashPeriod;
useconds_t flashSteps = flashRate / dutyCycle;
if (flashSteps >= 10) {
float flashStep = (maxBrightness - minBrightness) / flashSteps;
pin->brightness += waxing ? flashStep : -flashStep;
if (pin->brightness > maxBrightness) {
waxing = false;
pin->brightness = maxBrightness;
} else if (pin->brightness < minBrightness) {
waxing = true;
pin->brightness = minBrightness;
}
}
useconds_t mark = pin->brightness / maxBrightness * dutyCycle;
if (mark) {
GPIO_SET = 1 << pin->pin;
usleep(mark);
}
float spacePct = maxBrightness - pin->brightness;
useconds_t space = spacePct / maxBrightness * dutyCycle;
if (space) {
GPIO_CLR = 1 << pin->pin;
usleep(space);
}
}
}
// turn off the lamp when we have been signalled to shut down
GPIO_CLR = 1 << pin->pin;
daemonLog("thread %d finished and pin reset\n",pin->pin);
return NULL;
}
void dumpStatsFile() {
FILE * statsFile = fopen(statsFilePath, "w+");
if (statsFile) {
daemonLog("created stats file\n");
for (unsigned char pin = MIN_PIN;pin<NUM_PINS;pin++) {
if (pins[pin].thread) {
fprintf(statsFile,"pin %d : flash = %lu, brightness = %.0f, power = %d\n",pin,pins[pin].flashPeriod,pins[pin].brightness,pins[pin].powerOn);
}
}
fclose(statsFile);
daemonLog("finished stats file and closed\n");
} else {
perror("failed to create stats file");
}
}
void Daemon::log(QString str)
{
qDebug() << str;
if (m_daemonLogEnabled) {
emit daemonLog(str);
}
#ifdef WRITE_LOG_TO_FILE
str.append("\n");
m_outStream << str;
m_outStream.flush();
#endif
}
void doControlMessage(char * message) {
bool steadyMsg=strncmp(message,"s:",2)==0;
bool flashMsg=strncmp(message,"f:",2)==0;
bool relayControlMsg=strncmp(message,"p:",2)==0;
if (steadyMsg||flashMsg||relayControlMsg) {
daemonLog("received control message %s\n",message);
message+=2;
message[6]=0;
if (strnlen(message,6)<=6&&strnlen(message,6)>=4) {
char pinBuf[3]={0};
strncpy(pinBuf,message,2);
unsigned char pin = atoi(pinBuf);
daemonLog("adjusting pin %d\n",pin);
if (pin >= MIN_PIN && pin < NUM_PINS) {
INP_GPIO(pin);
OUT_GPIO(pin); // Define pin as output
message+=3;
unsigned char newParameter = atoi(message);
if (steadyMsg) {
pins[pin].flashPeriod=0;
pins[pin].brightness=fmaxf(fminf((float)newParameter,maxBrightness),minBrightness);
daemonLog("parameter is %s, interpreted as brightness %f\n",message,pins[pin].brightness);
} else if (flashMsg) {
if (newParameter<=0) newParameter = 1;
pins[pin].flashPeriod=100000*newParameter;
daemonLog("parameter is %s, interpreted as flash period %lu\n",message,pins[pin].flashPeriod);
} else if (relayControlMsg) {
newParameter=(bool)newParameter;
pins[pin].powerOn=newParameter;
pins[pin].flashPeriod=0;
pins[pin].brightness=0;
daemonLog("parameter is %s, interpreted as power on %d\n",message,pins[pin].powerOn);
}
if (!pins[pin].thread) {
int pin_thread_success = pthread_create(&pins[pin].thread, NULL, flasher, (void*)&pins[pin]);
assert(0 == pin_thread_success);
daemonLog("created thread for pin %d\n",pin);
}
} else {
daemonLog("invalid pin %d",pin);
}
} else {
daemonLog("invalid length control message - should be _:XX:YYY was %d - %s\n",strnlen(message,6),message);
}
}
}
// the main control function
// print help, if needed, setup signal handling for clean daemon exit, setup GPIO
// daemonize, setup fifo and wait for instructions
int main(int argc,char **argv)
{
// emit help and exit cleanly if they specify any parameters
if (argc>1) {
showHelp(argv[0]);
return 0;
}
// prepare signal handling for when we're a daemon (or not)
struct sigaction new_action, old_action;
new_action.sa_handler = sigInt;
sigemptyset (&new_action.sa_mask);
new_action.sa_flags = 0;
sigaction (SIGINT, NULL, &old_action);
if (old_action.sa_handler != SIG_IGN) {
sigaction (SIGINT, &new_action, NULL);
}
sigaction (SIGHUP, NULL, &old_action);
if (old_action.sa_handler != SIG_IGN) {
sigaction (SIGHUP, &new_action, NULL);
}
sigaction (SIGTERM, NULL, &old_action);
if (old_action.sa_handler != SIG_IGN) {
sigaction (SIGTERM, &new_action, NULL);
}
// map the gpio area, if we can't do this, there's no point even trying to be a daemon
if(map_peripheral(&gpio) == -1)
{
printf("Failed to map the physical GPIO registers into the virtual memory space.\n");
return -1;
}
// now the initial setup is done, attempt to make ourselves a daemon before continuing
// all logging from now on goes to a dedicated log file
// (from http://www.netzmafia.de/skripten/unix/linux-daemon-howto.html)
pid_t pid, sid;
pid = fork();
if (pid < 0) {
printf("failed to spawn a daemon (%s)\n",strerror(errno));
exit(EXIT_FAILURE);
}
if (pid > 0) {
exit(EXIT_SUCCESS);
}
umask(0);
debugFile = fopen(flasherLog, "w+");
if (!debugFile) {
perror("failed to create debug log file");
} else {
daemonLog("created log file\n");
}
sid = setsid();
if (sid < 0) {
daemonLog("%s failed to setsid\n",strerror(errno));
exit(EXIT_FAILURE);
}
if ((chdir(flasherPwd)) < 0) {
daemonLog("%s failed to chdir\n",strerror(errno));
exit(EXIT_FAILURE);
}
close(STDIN_FILENO); // this is enough to stop the daemon from working
close(STDOUT_FILENO);
close(STDERR_FILENO);
// we are now a daemon, logging to file
daemonLog("daemon running\n");
// then create one flasher for each pin we will use
for (unsigned char pin = MIN_PIN;pin<NUM_PINS;pin++) {
pins[pin].pin = pin;
}
// main loop, open the fifo and wait for messages or for interrupt
unlink(flasherPipe);
char buf[CMD_BUF];
int fifo_create_success = mkfifo(flasherPipe,0777);
if (fifo_create_success == 0 || errno == EEXIST) {
daemonLog("Waiting for messages on %s...\n",flasherPipe);
FILE * flasherfile = fopen(flasherPipe,"r");
if (flasherfile) {
while (keepRunning) {
if (fgets(buf,CMD_BUF,flasherfile)) {
doControlMessage(buf);
dumpStatsFile();
}
usleep(dutyCycle); // reduce CPU load
}
if (fclose(flasherfile)) {
daemonLog("%s failed to close fifo\n",strerror(errno));
}
if (unlink(statsFilePath)) {
daemonLog("%s failed to cleanup stats\n",strerror(errno));
}
} else {
daemonLog("%s failed to open fifo\n",strerror(errno));
}
if (unlink(flasherPipe)) {
daemonLog("%s failed to cleanup fifo\n",strerror(errno));
}
} else {
daemonLog("%s failed to create fifo\n",strerror(errno));
}
// either we couldn't open the fifo or we opened it, ran for a bit and received a shutdown...
daemonLog("preparing to shut down...\n");
// try to clean up all threads
for (unsigned char pin = MIN_PIN;pin<NUM_PINS;pin++) {
if (pins[pin].thread) {
pthread_join(pins[pin].thread,NULL);
daemonLog("thread %d done\n",pin);
}
}
return 0;
}
