WIP: add -1/--singleshot option

include/Channel.hpp

@@ -47,6 +47,7 @@ class Channel {
 	Channel(const std::list<Option> &pOptions, const std::string api, const std::string pUuid,
 			ReadingIdentifier::Ptr pIdentifier);
 	virtual ~Channel();
+	bool running();
 
 	// Doesn't touch the object, could also be static, but static breaks google mock.
 	void start(Ptr this_shared) {
@@ -70,8 +71,6 @@ class Channel {
 			pthread_cancel(_thread);
 	}
 
-	bool running() const { return _thread_running; }
-
 	const char *name() const { return _name.c_str(); }
 	std::list<Option> &options() { return _options; }
 

include/Config_Options.hpp

@@ -76,6 +76,7 @@ class Config_Options {
 	bool channel_index() const { return _channel_index; }
 	bool local() const { return _local; }
 	bool foreground() const { return _foreground; }
+	bool singleshot() const { return _singleshot; }
 
 	bool doRegistration() const { return _doRegistration; }
 
@@ -93,6 +94,8 @@ class Config_Options {
 
 	void foreground(const bool v) { _foreground = v; }
 
+	void singleshot(const bool v) { _singleshot = v; }
+
 	void doRegistration(const bool v) { _doRegistration = v; }
 
 	PushDataServer *pushDataServer() const { return _pds; }
@@ -113,6 +116,7 @@ class Config_Options {
 	int _channel_index : 1;  // give a index of all available channels via local interface
 	int _local : 1;          // enable local interface
 	int _foreground : 1;     // don't daemonize
+	int _singleshot : 1;     // only get a single reading from each meter, then exit
 	int _doRegistration : 1; // FIXME
 };
 

include/MeterMap.hpp

@@ -83,7 +83,7 @@ class MeterMap {
 	inline iterator end() { return _channels.end(); }
 	inline size_t size() { return _channels.size(); }
 
-	bool running() const { return _thread_running; }
+	bool running();
 
   private:
 	Meter::Ptr _meter;

src/Channel.cpp

@@ -89,6 +89,21 @@ Channel::Channel(const std::list<Option> &pOptions, const std::string apiProtoco
 	pthread_cond_init(&condition, NULL); // initialize thread syncronization helpers
 }
 
+bool Channel::running() {
+	if (!_thread_running)
+		return _thread_running;
+	int ret = pthread_tryjoin_np(_thread, NULL);
+	if (ret == EBUSY) {
+		// thread still running
+		_thread_running = true;
+	} else if (ret != 0) {
+		print(log_alert, "error from pthread_tryjoin_np()", name());
+	} else {
+		_thread_running = false;
+	}
+	return _thread_running;
+}
+
 /**
  * Free all allocated memory recursively
  */

src/Config_Options.cpp

@@ -41,13 +41,14 @@ static const char *option_type_str[] = {"null",   "boolean", "double", "int",
 
 Config_Options::Config_Options()
 	: _config("/etc/vzlogger.conf"), _log(""), _pds(0), _port(8080), _verbosity(0),
-	  _comet_timeout(30), _buffer_length(-1), _retry_pause(15), _local(false), _foreground(false) {
+	  _comet_timeout(30), _buffer_length(-1), _retry_pause(15), _local(false), _foreground(false),
+	  _singleshot(false) {
 	_logfd = NULL;
 }
 
 Config_Options::Config_Options(const std::string filename)
 	: _config(filename), _log(""), _pds(0), _port(8080), _verbosity(0), _comet_timeout(30),
-	  _buffer_length(-1), _retry_pause(15), _local(false), _foreground(false) {
+	  _buffer_length(-1), _retry_pause(15), _local(false), _foreground(false), _singleshot(false) {
 	_logfd = NULL;
 }
 

src/MeterMap.cpp

@@ -77,6 +77,27 @@ void MeterMap::start() {
 	}
 }
 
+bool MeterMap::running() {
+	int ret;
+	if (!_thread_running)
+		return _thread_running;
+	for (iterator it = _channels.begin(); it != _channels.end(); it++) {
+		if ((*it)->running())
+			return _thread_running;
+	}
+	ret = pthread_tryjoin_np(_thread, NULL);
+	if (ret == EBUSY) {
+		// thread still running
+		return _thread_running;
+	} else if (ret != 0) {
+		print(log_alert, "error from pthread_tryjoin_np()", _meter->name());
+	} else {
+		// tread has exited
+	}
+	_thread_running = false;
+	return false;
+}
+
 void MeterMap::cancel() { // is called from MapContainer::quit which is called from sigint handler
 						  // handler ::quit
 	print(log_finest, "MeterMap::cancel entered...", _meter->name());

src/protocols/MeterS0.cpp

@@ -35,8 +35,11 @@
 
 #include "Options.hpp"
 #include "protocols/MeterS0.hpp"
+#include <Config_Options.hpp>
 #include <VZException.hpp>
 
+extern Config_Options options;
+
 MeterS0::MeterS0(std::list<Option> options, HWIF *hwif, HWIF *hwif_dir)
 	: Protocol("s0"), _hwif(hwif), _hwif_dir(hwif_dir), _counter_thread_stop(false),
 	  _send_zero(false), _debounce_delay_ms(0), _nonblocking_delay_ns(1e5), _first_impulse(true) {
@@ -417,10 +420,12 @@ ssize_t MeterS0::read(std::vector<Reading> &rds, size_t n) {
 			rds[ret].value(value);
 			++ret;
 		}
-		rds[ret].identifier(new StringIdentifier("Impulse"));
-		rds[ret].time(req);
-		rds[ret].value(t_imp);
-		++ret;
+		if (!options.singleshot()) {
+			rds[ret].identifier(new StringIdentifier("Impulse"));
+			rds[ret].time(req);
+			rds[ret].value(t_imp);
+			++ret;
+		}
 	}
 
 	if (_send_zero || t_imp_neg > 0) {
@@ -431,10 +436,12 @@ ssize_t MeterS0::read(std::vector<Reading> &rds, size_t n) {
 			rds[ret].value(value);
 			++ret;
 		}
-		rds[ret].identifier(new StringIdentifier("Impulse_neg"));
-		rds[ret].time(req);
-		rds[ret].value(t_imp_neg);
-		++ret;
+		if (!options.singleshot()) {
+			rds[ret].identifier(new StringIdentifier("Impulse_neg"));
+			rds[ret].time(req);
+			rds[ret].value(t_imp_neg);
+			++ret;
+		}
 	}
 	if (_first_impulse && ret > 0)
 		_first_impulse = false;

src/threads.cpp

@@ -166,6 +166,9 @@ void *reading_thread(void *arg) {
 				}
 			}
 
+			if (options.singleshot())
+				break;
+
 			if (mtr->interval() > 0) {
 				print(log_info, "Next reading in %i seconds", mtr->name(), mtr->interval());
 				sleep(mtr->interval());
@@ -220,6 +223,9 @@ void *logging_thread(void *arg) { // is started by Channel::start and stopped vi
 		try {
 			ch->wait();
 			api->send();
+
+			if (options.singleshot())
+				break;
 		} catch (std::exception &e) {
 			print(log_alert, "Logging thread failed due to: %s", ch->name(), e.what());
 		}

src/vzlogger.cpp

@@ -76,6 +76,7 @@ const struct option long_options[] = {
 	{"config", required_argument, 0, 'c'},
 	{"log", required_argument, 0, 'o'},
 	{"foreground", no_argument, 0, 'f'},
+	{"singleshot", no_argument, 0, '1'},
 #ifdef LOCAL_SUPPORT
 	{"httpd", no_argument, 0, 'l'},
 	{"httpd-port", required_argument, 0, 'p'},
@@ -94,6 +95,7 @@ const char *long_options_descs[] = {
 	"configuration file",
 	"log file",
 	"run in foreground, do not daemonize",
+	"get only one reading for each meter, then exit",
 #ifdef LOCAL_SUPPORT
 	"activate local interface (tiny HTTPd which serves live readings)",
 	"TCP port for HTTPd",
@@ -285,7 +287,7 @@ void signalHandlerQuit(int sig) {
  */
 int config_parse_cli(int argc, char *argv[], Config_Options *options) {
 	while (1) {
-		int c = getopt_long(argc, argv, "c:o:p:lhrVfv:", long_options, NULL);
+		int c = getopt_long(argc, argv, "c:o:p:lhrVf1v:", long_options, NULL);
 
 		/* detect the end of the options. */
 		if (c == -1)
@@ -310,6 +312,10 @@ int config_parse_cli(int argc, char *argv[], Config_Options *options) {
 			options->foreground(1);
 			break;
 
+		case '1':
+			options->singleshot(1);
+			break;
+
 		case 'c': /* config file */
 			options->config(optarg);
 			break;