esp32-nmea2000-obp60/lib/exampletask/GwExampleTask.cpp

87 lines
3.4 KiB
C++

//we only compile for some boards
#ifdef BOARD_TEST
#include "GwExampleTask.h"
#include "GwApi.h"
#define INVALID_COORD -99999
class GetBoatDataRequest: public GwMessage{
private:
GwApi *api;
public:
double latitude;
double longitude;
GetBoatDataRequest(GwApi *api):GwMessage(F("boat data")){
this->api=api;
}
virtual ~GetBoatDataRequest(){}
protected:
/**
* this methos will be executed within the main thread
* be sure not to make any time consuming or blocking operation
*/
virtual void processImpl(){
//api->getLogger()->logDebug(GwLog::DEBUG,"boatData request from example task");
/*access the values from boatData (see GwBoatData.h)
by using getDataWithDefault it will return the given default value
if there is no valid data available
so be sure to use a value that never will be a valid one
alternatively you can check using the isValid() method at each boatData item
*/
latitude=api->getBoatData()->Latitude->getDataWithDefault(INVALID_COORD);
longitude=api->getBoatData()->Longitude->getDataWithDefault(INVALID_COORD);
};
};
void exampleTask(void *param){
GwApi *api=(GwApi*)param;
GwLog *logger=api->getLogger();
//------
//initialization goes here
//------
bool hasPosition=false;
while(true){
delay(1000);
/*
* getting values from the internal data store (boatData) requires some special handling
* our tasks runs (potentially) at some time on a different core then the main code
* and as the boatData has no synchronization (for performance reasons)
* we must ensure to access it only from the main thread.
* The pattern is to create a request object (a class that inherits from GwMessage -
* GetBoatDataRequest above)
* and to access the boatData in the processImpl method of this object.
* Once the object is created we enqueue it into a request queue and wait for
* the main thread to call the processImpl method (sendAndWait).
* Afterwards we can use the data we have stored in the request.
* As this request object can be accessed from different threads we must be careful
* about it's lifetime.
* The pattern below handles this correctly. We do not call delete on this object but
* instead call the "unref" Method when we don't need it any more.
*/
GetBoatDataRequest *r=new GetBoatDataRequest(api);
if (api->getQueue()->sendAndWait(r,10000) != GwRequestQueue::MSG_OK){
r->unref(); //delete the request
api->getLogger()->logDebug(GwLog::ERROR,"request not handled");
continue;
}
if (r->latitude == INVALID_COORD || r->longitude == INVALID_COORD){
if (hasPosition){
logger->logDebug(GwLog::ERROR,"position lost...");
hasPosition=false;
}
}
else{
//do something with the data we have from boatData
if (! hasPosition){
logger->logDebug(GwLog::LOG,"postion now available lat=%f, lon=%f",
r->latitude,r->longitude);
hasPosition=true;
}
}
r->unref(); //delete the request
}
vTaskDelete(NULL);
}
#endif