Thread class. More...

#include <pithread.h>

Inheritance diagram for PIThread:

[legend]

Public Types
enum	Priority { piLowerst , piLow , piNormal , piHigh , piHighest }
	Priority of thread. More...

Public Member Functions
	PIThread (void *data, ThreadFunc func, bool startNow=false, PISystemTime loop_delay={})
	Contructs thread with custom data "data", external function "func" and main loop delay "loop_delay".

	PIThread (std::function< void()> func, bool startNow=false, PISystemTime loop_delay={})
	Contructs thread with external function "func" and main loop delay "loop_delay".

	PIThread (bool startNow=false, PISystemTime loop_delay={})
	Contructs thread with main loop delay "loop_delay".

bool	start ()
	Start thread.

bool	start (PISystemTime loop_delay)
	Start thread.

bool	start (ThreadFunc func)
	Start thread.

bool	start (ThreadFunc func, PISystemTime loop_delay)
	Start thread.

bool	start (std::function< void()> func)
	Start thread.

bool	start (std::function< void()> func, PISystemTime loop_delay)
	Start thread.

bool	startOnce ()
	Start thread without internal loop. More...

bool	startOnce (ThreadFunc func)
	Start thread without internal loop. More...

bool	startOnce (std::function< void()> func)
	Start thread without internal loop.

bool	stopAndWait (PISystemTime timeout={})
	Stop thread and wait for finish. Returns false if timeout expired.

void	setData (void *d)
	Set common data passed to external function.

void	setSlot (ThreadFunc func)
	Set external function that will be executed after every run()

void	setSlot (std::function< void()> func)
	Set external function that will be executed after every run()

void	setPriority (PIThread::Priority prior)
	Set thread priority.

void *	data () const
	Returns common data passed to external function.

PIThread::Priority	priority () const
	Return thread priority.

bool	isRunning () const
	Return if thread is running.

bool	isStopping () const
	Return if thread is stopping.

bool	waitForStart (PISystemTime timeout={})
	Wait for thread start.

bool	waitForStart (int timeout_msecs) DEPRECATEDM("use waitForStart(PISystemTime)")

bool	waitForFinish (PISystemTime timeout={})
	Wait for thread finish. Returns false if timeout expired.

bool	waitForFinish (int timeout_msecs) DEPRECATEDM("use waitForFinish(PISystemTime)")

void	needLockRun (bool need)
	Set necessity of lock every run() with internal mutex.

PIMutex &	mutex () const
	Returns internal mutex.

llong	tid () const
	Returns thread ID.

Public Member Functions inherited from PIObject
	PIObject (const PIString &name=PIString())
	Contructs PIObject with name "name".

PIString	name () const
	Returns object name.

virtual const char *	className () const
	Returns object class name.

virtual const char *	parentClassName () const
	Returns parent class name.

bool	debug () const
	Return if piCoutObj of this object is active.

void	setName (const PIString &name)
	Set object name.

void	setDebug (bool debug)
	Set object piCoutObj active.

PIVariant	property (const char *name) const
	Returns property with name "name".

void	setProperty (const char *name, const PIVariant &value)
	Set property with name "name" to "value". If there is no such property in object it will be added.

bool	isPropertyExists (const char *name) const
	Returns if property with name "name" exists.

PIStringList	scopeList () const
	Returns subclass scope of this object (including this class name)

void	piDisconnect (const PIString &sig, PIObject dest, void ev_h)
	Disconnect object from all connections with event name "sig", connected to destination object "dest" and handler "ev_h".

void	piDisconnect (const PIString &sig, PIObject *dest)
	Disconnect object from all connections with event name "sig", connected to destination object "dest".

void	piDisconnect (const PIString &sig)
	Disconnect object from all connections with event name "sig".

bool	isPIObject () const
	Returns if this is valid PIObject (check signature)

template<typename T >
bool	isTypeOf () const
	Returns if this is valid PIObject subclass "T" (check signature and classname)

template<typename T >
T *	cast () const
	Returns cast to T if this is valid subclass "T" (check by isTypeOf()) or "nullptr".

void	callQueuedEvents ()
	Execute all posted events from CONNECTU_QUEUED connections.

bool	maybeCallQueuedEvents ()
	Check if any CONNECTU_QUEUED connections to this object and execute them. More...

void	deleteLater ()
	Mark object to delete. More...

void	deleted (PIObject *o)
	Raise before object delete. More...

Static Public Member Functions
static void	runOnce (PIObject object, const char handler, const PIString &name=PIString())
	Call event handler "handler" of object "object" in separate thread. More...

static void	runOnce (std::function< void()> func, const PIString &name=PIString())
	Call lambda expression "func" in separate thread. More...

Static Public Member Functions inherited from PIObject
static void	piDisconnect (PIObject src, const PIString &sig, PIObject dest, void *ev_h)
	Disconnect object "src" from all connections with event name "sig", connected to destination object "dest" and handler "ev_h".

static void	piDisconnect (PIObject src, const PIString &sig, PIObject dest)
	Disconnect object "src" from all connections with event name "sig", connected to destination object "dest".

static void	piDisconnect (PIObject *src, const PIString &sig)
	Disconnect object "src" from all connections with event name "sig".

static PIObject *	findByName (const PIString &name)
	Returns PIObject* with name "name" or 0, if there is no object found.

static bool	isPIObject (const PIObject *o)
	Returns if "o" is valid PIObject (check signature)

template<typename T >
static bool	isTypeOf (const PIObject *o)
	Returns if "o" is valid PIObject subclass "T" (check signature and classname)

Protected Member Functions
virtual void	begin ()
	Function executed once at the start of thread.

virtual void	run ()
	Function executed at every "loop_delay" msecs until thread was stopped.

virtual void	end ()
	Function executed once at the end of thread.

Protected Member Functions inherited from PIObject
PIObject *	emitter () const
	Returns PIObject* which has raised an event. This value is correct only in definition of some event handler.

virtual void	propertyChanged (const char *name)
	Virtual function executes after property with name "name" has been changed.

Handlers
void	stop ()
	Stop thread. More...

void	terminate ()
	Strongly stop thread. More...

void	lock () const
	Lock internal mutex.

void	unlock () const
	Unlock internal mutex.

Events
void	started ()
	Raise on thread start.

void	stopped ()
	Raise on thread stop.

Additional Inherited Members
Related Functions inherited from PIObject
#define	piCoutObj
	Macro used for conditional (piDebug && PIObject::debug()) output to PICout(StdOut) for subclasses of PIObject.

#define	piCerrObj
	Macro used for conditional (piDebug && PIObject::debug()) output to PICout(StdErr) for subclasses of PIObject.

#define	PIOBJECT(name)
	You should use this macro after class declaration to use EVENT and EVENT_HANDLER and correct piCoutObj output.

#define	PIOBJECT_SUBCLASS(name, parent)
	You should use this macro after class declaration to use EVENT and EVENT_HANDLER of parent class, and scopeList()

#define	EVENT_HANDLER0(ret, name) ret name()
	Declare event handler with name "name" and return type "ret", ret name()

#define	EVENT_HANDLER1(ret, name, type0, var0) ret name(type0 var0)
	Declare event handler with name "name" and return type "ret", ret name(type0 var0)

#define	EVENT_HANDLER2(ret, name, type0, var0, type1, var1) ret name(type0 var0, type1 var1)
	Declare event handler with name "name" and return type "ret", ret name(type0 var0, type1 var1)

#define	EVENT_HANDLER3(ret, name, type0, var0, type1, var1, type2, var2) ret name(type0 var0, type1 var1, type2 var2)
	Declare event handler with name "name" and return type "ret", ret name(type0 var0, type1 var1, type2 var2)

#define	EVENT_HANDLER4(ret, name, type0, var0, type1, var1, type2, var2, type3, var3) ret name(type0 var0, type1 var1, type2 var2, type3 var3)
	Declare event handler with name "name" and return type "ret", ret name(type0 var0, type1 var1, type2 var2, type3 var3)

#define	EVENT_HANDLER EVENT_HANDLER0
	Synonym of EVENT_HANDLER0.

#define	EVENT_VHANDLER0(ret, name) virtual ret name()
	Declare virtual event handler with name "name" and return type "ret", virtual ret name()

#define	EVENT_VHANDLER1(ret, name, type0, var0) virtual ret name(type0 var0)
	Declare virtual event handler with name "name" and return type "ret", virtual ret name(type0 var0)

#define	EVENT_VHANDLER2(ret, name, type0, var0, type1, var1) virtual ret name(type0 var0, type1 var1)
	Declare virtual event handler with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1)

#define	EVENT_VHANDLER3(ret, name, type0, var0, type1, var1, type2, var2) virtual ret name(type0 var0, type1 var1, type2 var2)
	Declare virtual event handler with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1, type2 var2)

#define	EVENT_VHANDLER4(ret, name, type0, var0, type1, var1, type2, var2, type3, var3) virtual ret name(type0 var0, type1 var1, type2 var2, type3 var3)
	Declare virtual event handler with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1, type2 var2, type3 var3)

#define	EVENT_VHANDLER EVENT_VHANDLER0
	Synonym of EVENT_VHANDLER0.

#define	EVENT0(name) void name();
	Declare event with name "name", void name();.

#define	EVENT1(name, type0, var0) void name(type0 var0);
	Declare event with name "name", void name(type0 var0);.

#define	EVENT2(name, type0, var0, type1, var1) void name(type0 var0, type1 var1);
	Declare event with name "name", void name(type0 var0, type1 var1);.

#define	EVENT3(name, type0, var0, type1, var1, type2, var2) void name(type0 var0, type1 var1, type2 var2);
	Declare event with name "name", void name(type0 var0, type1 var1, type2 var2);.

#define	EVENT4(name, type0, var0, type1, var1, type2, var2, type3, var3) void name(type0 var0, type1 var1, type2 var2, type3 var3);
	Declare event with name "name", void name(type0 var0, type1 var1, type2 var2, type3 var3);.

#define	EVENT EVENT0
	Synonym of EVENT0.

#define	CONNECTU(src, event, dest, handler)
	Connect event "event" from object "src" to event handler or event "handler" of object "dest". More...

#define	CONNECTU_QUEUED(src, event, dest, handler, performer)
	Connect event "event" from object "src" to event handler or event "handler" of object "dest". More...

#define	CONNECTL(src, event, functor)
	Connect event "event" from object "src" to lambda-expression "functor". More...

#define	CONNECT0(ret, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists. More...

#define	CONNECT1(ret, type0, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists. More...

#define	CONNECT2(ret, type0, type1, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists. More...

#define	CONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists. More...

#define	CONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists. More...

#define	CONNECT CONNECT0
	Synonym of CONNECT0. More...

#define	WEAK_CONNECT0(ret, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists. More...

#define	WEAK_CONNECT1(ret, type0, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists. More...

#define	WEAK_CONNECT2(ret, type0, type1, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists. More...

#define	WEAK_CONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists. More...

#define	WEAK_CONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	Connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists. More...

#define	WEAK_CONNECT WEAK_CONNECT0
	Synonym of WEAK_CONNECT0. More...

#define	DISCONNECT0(ret, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT1(ret, type0, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT2(ret, type0, type1, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT DISCONNECT0
	Synonym of DISCONNECT0.

#define	HANDLER(handler)
	Returns pointer to events handler "handler".

Detailed Description

Thread class.

This class allow you exec your code in separate thread.

Synopsis

Multithreading allow you to execute code in several threads simultaneously. This trend allow you to use all cores of modern processors, but there are many dangers.

This class provide virtual functions begin(), run() and end(), which describes start, execution and finish work of some process. These functions executes in separate thread. When you execute start(int), PIThread create separate system thread and sequentially executes function begin(), run() and end(). You can reimplement each function and write your own code to execute.

Scheme of functions executing:

virtual begin()
event started()
while (isRunning()) {     // while not stop()
    virtual run()
    ThreadFunc()          // Slot or lambda
    piMSleep(loop_delay)  // if loop_delay > 0
}
event stopped()
virtual end()

If no internal loop needed, you can use startOnce() method instead of start(int).

In this case scheme is next:

virtual begin()
event started()
virtual run()
ThreadFunc()    // Slot or lambda
event stopped()
virtual end()

Unlike from directly using "pthread" or some similar you doesn`t need to write your own main thread cycle and sleep at every cycle end. PIThread make it for you, and your job is to set sleep value from contructor or when starting thread, and reimplement begin(), run() and end() functions.

Using with internal loop

class MyThread: public PIThread {
    PIOBJECT_SUBCLASS(MyThread, PIThread)
public:
    void begin() override {piCout << "thread begin";}
    void run() override {piCout << "thread run" << ++cnt;}
    void end() override {piCout << "thread end";}
private:
    int cnt = 0;
};
 
int main(int argc, char * argv[]) {
    MyThread mt;
    mt.start(100);
    piMSleep(500);
    mt.stop(true);
    return 0;
}
 
// thread begin
// thread run 1
// thread run 2
// thread run 3
// thread run 4
// thread run 5
// thread end

Using without internal loop

class MyThread: public PIThread {
    PIOBJECT_SUBCLASS(MyThread, PIThread)
public:
    void begin() override {piCout << "thread begin";}
    void run() override {piCout << "thread run" << ++cnt;}
    void end() override {piCout << "thread end";}
private:
    int cnt = 0;
};
 
int main(int argc, char * argv[]) {
    MyThread mt;
    mt.startOnce();
    piMSleep(500);
    mt.stop(true);
    return 0;
}
 
// thread begin
// thread run 1
// thread end

Using without subclassing

You can use PIThread without subclassing by using "ThreadFunc" pointer that can be set from constructor or by overloaded function start(ThreadFunc func, int loop_delay). If "func" if not null this function will be executed after run().

ThreadFunc is any static function with format "void func(void * data)", or lambda expression with format [...]( ){...}. "Data" is custom data set from constructor or with setData() function.

Also you can connect to event started(), but in this case you should to white your thread main cycle, because this event raised only one time after thread start.

Using with internal loop

void myThreadFunc(void * d) {
    int * cnt = (int*)d;
    piCout << "thread run" << ++(*cnt);
}
 
int main(int argc, char * argv[]) {
    int cnt = 0;
    PIThread mt;
    mt.setData(&cnt);
    mt.start(myThreadFunc, 100);
    piMSleep(500);
    mt.stop(true);
    return 0;
}
 
// thread run 1
// thread run 2
// thread run 3
// thread run 4
// thread run 5

Using without internal loop

void myThreadFunc(void * d) {
    int * cnt = (int*)d;
    piCout << "thread run" << ++(*cnt);
}
 
int main(int argc, char * argv[]) {
    int cnt = 0;
    PIThread mt;
    mt.setData(&cnt);
    mt.startOnce(myThreadFunc);
    piMSleep(500);
    mt.stop(true);
    return 0;
}
 
// thread run 1

Using with lambda expression

int main(int argc, char * argv[]) {
    int cnt = 0;
    PIThread mt;
    mt.start([&cnt](){
        piCout << "thread run" << ++cnt;
    }, 100);
    piMSleep(500);
    mt.stop(true);
    return 0;
}
 
// thread run 1
// thread run 2
// thread run 3
// thread run 4
// thread run 5

Using with event

class MyObj: public PIObject {
    PIOBJECT(MyObj)
public:
    EVENT_HANDLER(void, threadRun) {
        piForTimes (5) {
            piCout << "threadRun" << ++cnt;
            piMSleep(100);
        }
    };
private:
    int cnt = 0;
};
 
int main(int argc, char * argv[]) {
    MyObj mo;
    PIThread mt;
    CONNECTU(&mt, started, &mo, threadRun);
    mt.startOnce();
    mt.stop(true);
    return 0;
}
 
// threadRun 1
// threadRun 2
// threadRun 3
// threadRun 4
// threadRun 5

Locking

PIThread has inrternal mutex that can be locked and unlocked every run() if you set this flag with function needLockRun(true). Also you can access to this mutex by functions lock(), unlock() and mutex(). Using this functions outside of thread together with needLockRun(true) can defend your data.

Member Enumeration Documentation

◆ Priority

enum PIThread::Priority

Priority of thread.

Enumerator
piLowerst	Lowest
piLow	Low
piNormal	Normal, this is default priority of threads and timers
piHigh	High
piHighest	Highest

Member Function Documentation

◆ startOnce() [1/2]

bool PIThread::startOnce ( )

Start thread without internal loop.

Start execution of run() once. Thread also exec external function set by setSlot() if its not null. \return \c false if thread already started or cant start thread

◆ startOnce() [2/2]

bool PIThread::startOnce ( ThreadFunc func )

Start thread without internal loop.

Overloaded function. Set external function "func" before start.

Returns: false if thread already started or can`t start thread

◆ stop()

void PIThread::stop ( )

Stop thread.

Mark thread to stop execution and wait for finish if "wait" is true. Thread can be stopped only outside of run() or external method.

Warning: This function can block for infinite time if "wait" is true and any of thread function is busy forever.

◆ terminate()

void PIThread::terminate ( )

Strongly stop thread.

Stop execution of thread immediately.

Warning: Memory can be corrupted, try not to use this method!

◆ waitForStart()

bool PIThread::waitForStart ( int timeout_msecs = -1 )

inline

Block until thread start within "timeout_msecs" or forever if "timeout_msecs" < 0

Returns: true if thread started less than timeout; false if timeout is exceeded

◆ waitForFinish()

bool PIThread::waitForFinish ( int timeout_msecs = -1 )

inline

Block until thread finish for "timeout_msecs" or forever if "timeout_msecs" < 0

Returns: true if thread finished less than timeout; false if timeout is exceeded

◆ runOnce() [1/2]

void PIThread::runOnce	(	PIObject *	object,
		const char *	handler,
		const PIString &	name = `PIString()`
	)

static

Call event handler "handler" of object "object" in separate thread.

This method create PIThread with name "name" and execute event handler "handler" of object "object" in this thread.
This PIThread automatically delete on function finish.

class MyObj: public PIObject {
    PIOBJECT(MyObj)
public:
    EVENT_HANDLER(void, threadRun) {
        piForTimes (5) {
            piCout << "threadRun";
            piMSleep(100);
        }
    };
};
 
int main(int argc, char * argv[]) {
    MyObj mo;
    PIThread::runOnce(&mo, "threadRun");
    piMSleep(1000); // wait for thread finish
    return 0;
}

◆ runOnce() [2/2]

void PIThread::runOnce	(	std::function< void()>	func,
		const PIString &	name = `PIString()`
	)

static

Call lambda expression "func" in separate thread.

This method create PIThread with name "name" and execute lambda expression "func" in this thread.
This PIThread automatically delete on function finish.
"func" shouldn`t have arguments.

PIThread::runOnce([](){
    piForTimes(5) {
        piCout << "thread func";
        piMSleep(100);
    }
});
piMSleep(1000);

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Handlers

Events

Additional Inherited Members