C++ vector push_back with class object - c++

Question

I've been using this site for a while and so far never needed to ask a new question (found all answers I've needed until now).
I need to push_back multiple objects into a vector but VS throws an error (This may be due to a corruption of the heap, which indicates a bug in PVSS00DataGate.exe or any of the DLLs it has loaded) that I cannot seem to work out for myself.
Here is what I am trying to do, it works to push_back the first object into the vector but when I try to push_back a second object that is when the error occurs.
class HWObject{}
void DataLogger::WriteNewMessages()
{
unsigned int iBattery = 0;
unsigned int iSignal = 0;
TimeVar tTimeStamp;
// I want to store all HWObjects in a temporary vector (loggerData)
std::vector<HWObject> loggerData;
CharString strElement;
strElement.format( "batteryCondition.value" );
SendOneValuePVSS( (const char *)strElement, iBattery, tTimeStamp );
strElement.format( "signalStrength.value" );
SendOneValuePVSS( (const char *)strElement, iSignal, tTimeStamp );
}
void DataLogger::SendOneValuePVSS(const char *szElementName, double dValue, TimeVar, &tValue)
{
HWObject obj;
obj.setOrgTime(tValue); // Current time
obj.setTimeOfPeriphFlag();
CharString address;
address = strID;
address += ".";
address += szElementName;
obj.setAddress(address);
loggerData.reserve( loggerData.size() + 1 );
loggerData.push_back( obj );
obj.cutData();
}
dataLogger is declared in
class DataLogger
{
public:
std::vector<HWObject> loggerData;
...
}
Here is the class HWObject, I didn't want to overwhelm you with code.
public:
/** Default constructor*/
HWObject();
/** Constructor, which sets the periphAddr and transformationType.
* #param addressString address of the HW object
* #param trans type of transformation
*/
HWObject(const char* addressString, TransformationType trans);
/** Destructor. If the date pointer is not NULL, it is deleted.
*/
virtual ~HWObject();
/** Creates a new HWObject
* This function returns an empty HWObject, no properties are duplicated or copied!
* #classification public use, overload, call base
*/
virtual HWObject * clone() const;
/** Reset all pvss2 relevant parts of the HWObject. when overloading this member
* don't forget to call the basic function!
* #classification public use, overload, call base
*/
virtual void clear();
/** Gets pointer to data
* #return pointer to data
*/
const PVSSchar * getDataPtr() const { return dataPtr; }
/** Gets the data buffer pointer
* #return data buffer pointer
*/
PVSSchar * getData() { return dataPtr; }
/** Cut the data buffer out of the HWObject.
* This function is used to avoid the deletion
* of the data buffer, when a new pointer is set using
* setData() or the HWObject is deleted.
* #return pointer to the data of the HWObject
*/
PVSSchar * cutData();
/** Get the data buffer lenght
* #return length of the data buffer
*/
PVSSushort getDlen() const { return dataLen; }
/** Set ptr to the data buffer, pointer is captured.
* The actual data pointer in the HWObject is deleted,
* if it is not NULL. To avoid the deletion use cutData()
* in order to cut out the pointer.
* #param ptr pointer to new data
*/
void setData(PVSSchar *ptr);
/** Set the data length
* #param len length to be set
*/
void setDlen(const PVSSushort len) { dataLen = len; }
/** Get the periph address
* #return periph address string
*/
const CharString & getAddress() const { return address; }
/** Get the transformation type
* #return type of transformation
*/
TransformationType getType() const { return transType; }
/** Set the transformation type
* #param typ type of transformation for setting
*/
void setType(const TransformationType typ) { transType = typ; }
/** Get the subindex
* #return subindex
*/
PVSSushort getSubindex() const { return subindex; }
/** Set the subindex
* #param sx subindex to be set
*/
void setSubindex( const PVSSushort sx) { subindex = sx; }
/** Get the origin time
* #return origin time
*/
const TimeVar& getOrgTime() const { return originTime; }
/** Get the origin time
* #return oriin time
*/
TimeVar& getOrgTime() { return originTime; }
/** Set the origin time
* #param tm origin time to be set
*/
void setOrgTime(const TimeVar& tm) { originTime = tm; }
/** Get HWObject purpose
* #return objSrcType
*/
ObjectSourceType getObjSrcType() const { return objSrcType; }
/** Set HWObject purpose
* #param tp objSrcType
*/
void setObjSrcType(const ObjectSourceType tp) { objSrcType = tp; }
/** Get number of elements in data buffer
* #return number of elements in data buffer
*/
PVSSushort getNumberOfElements() const { return number_of_elements; }
/** Set number of elements in data buffer
* #param var number of elements in data buffer
*/
void setNumberOfElements(const PVSSushort var) { number_of_elements = var; }
/** Prints the basic HWObject information on stderr.
* in case of overloading don't forget to call the base function!
* #classification public use, overload, call base
*/
virtual void debugPrint() const;
/** Prints th basic HWObject info in one CharString for internal debug DP.
* in case of overloading call base function first, then append specific info
* #classification public use, overload, call base
*/
virtual CharString getInfo() const;
/** Set the periph address
* #param adrStr pointer to address string
*/
virtual void setAddress(const char *adrStr);
/** Set the additional data (flag, orig time, valid user byte,etc)
* #param data aditional flags that be set
* #param subix subindex, use subix 0 for setting values by default
*/
virtual void setAdditionalData(const RecVar &data, PVSSushort subix);
/** Set the 'origin time comes from periph' flag
*/
void setTimeOfPeriphFlag()
{
setSbit(DRV_TIME_OF_PERIPH);
}
/** Check whether time comes from periph
* #return PVSS_TRUE if the time is from perip
*/
PVSSboolean isTimeFromPeriph() const
{
// If isTimeOfPeriph is set, it must be valid
return getSbit(DRV_TIME_OF_PERIPH);
}
/** Set the flag if you want to receive callback if event has answered the value change
*/
void setWantAnswerFlag()
{
setSbit(DRV_WANT_ANSWER);
}
/** Get the status of the 'want answer, flag
*/
PVSSboolean getWantAnswerFlag() const
{
// If isTimeOfPeriph is set, it must be valid
return getSbit(DRV_WANT_ANSWER);
}
/** Set the user bit given by input parameter.
* Status bits defined by the enum DriverBits
* #param bitno bit number
* #return PVSS_TRUE if bit was set
*/
PVSSboolean setSbit(PVSSushort bitno)
{
return (status.set(bitno) && status.set(bitno + (PVSSushort)DRV_VALID_INVALID - (PVSSushort)DRV_INVALID));
}
/** Clear the user bit given by input parameter
* #param bitno bit number
* #return PVSS_TRUE if bit was cleared
*/
PVSSboolean clearSbit(PVSSushort bitno)
{
return (status.clear(bitno) && status.set(bitno + (PVSSushort)DRV_VALID_INVALID - (PVSSushort)DRV_INVALID));
}
PVSSboolean isValidSbit(PVSSushort bitno) const
{
return status.get(bitno + (PVSSushort)DRV_VALID_INVALID - (PVSSushort)DRV_INVALID);
}
/** Check any bit
* #param bitno bit number
* #return status of the bit on bitno position
*/
PVSSboolean getSbit(PVSSushort bitno) const {return status.get(bitno);}
/** Clear all status bits
* return status of clear all
*/
PVSSboolean clearStatus() {return status.clearAll();}
/** Get the status of this object
* #return bit vector status
*/
const BitVec & getStatus() const {return status;}
/** Set status of the bit vector
* #param bv deference to bit vector to be set as status
*/
void setStatus(const BitVec &bv) {status = bv;}
/** Set a user byte in the status.
* #param userByteNo number of user byte range 0..3
* #param val value to set
* #return PVSS_TRUE execution OK
* PVSS_FALSE in case of error
*/
PVSSboolean setUserByte (PVSSushort userByteNo, PVSSuchar val);
/** Reads a user byte from the status.
* #param userByteNo number of user byte range 0..3
* #return the requested user byte
*/
PVSSuchar getUserByte (PVSSushort userByteNo) const;
/** Check validity of user byte.
* #param userByteNo number of user byte range 0..3
* #return PVSS_TRUE user byte is valid
* PVSS_FALSE user byte is not valid
*/
PVSSboolean isValidUserByte(PVSSushort userByteNo) const;
/** Format status bits into a string
* #param str status bits converted to string
*/
void formatStatus (CharString & str) const ;
// ------------------------------------------------------------------
// internal ones
/** Read data from bin file
* #param fp file handle
*/
virtual int inFromBinFile( FILE *fp );
/** Write data to bin file
* #param fp file handle
*/
virtual int outToBinFile( FILE *fp );
/** Set data length
* #param dlen data length
*/
void setDlenLlc (PVSSushort dlen) {dataLenLlc = dlen;}
virtual void updateBufferLlc (HWObject * hwo, int offset1 = 0);
virtual int compareLlc (HWObject * hwo, int offset1 = 0, int offset2 = 0, int len = -1);
/** Get dataLenLlc
* #return dataLenLlc
*/
PVSSushort getDlenLlc () const {return dataLenLlc;}
/** Function to delete the data buffer; overload if special deletion must be done
*/
virtual void deleteData ();
/** Set HW identifier
* #param id hw identifier to be set
*/
void setHwoId(PVSSulong id) {hwoId = id;}
/** Get HW identifier
* #return hw identifier
*/
PVSSulong getHwoId() const {return hwoId;}
protected:
/// the dynamic data buffer
PVSSchar* dataPtr;
/// the data buffer len
PVSSushort dataLen;
/// the pvss2 periph address string
CharString address;
/// the start subix for the data buffer
PVSSushort subindex;
/// the datatype of the data in the buffer (i.e. transformationtype)
TransformationType transType;
/// the time of income, normally set by the constructor
TimeVar originTime;
/// the purpose of this HWObject
ObjectSourceType objSrcType;
/// the number of elements in the data buffer, used for arrays and records
PVSSushort number_of_elements; // fuer array!!!
/// the user bits of the original config
BitVec status;
private:
PVSSushort dataLenLlc;
PVSSulong hwoId;
};

Answer 1

You're not showing the important parts. I'd guess that HWObject has
dynamically allocated memory, and doesn't implement the rule of three
(copy constructor, assignment operator and destructor). But it's only a
guess. (Unless you're using special techniques like reference counting
or smart pointers, copy must do a deep copy, and assignment should
probably use the swap idiom.)
Also, there's no point in reserving size() + 1 just before
push_back.