I have a program which allows the user to play Dominoes against 3 CPU players, with varying difficulty. Each CPU player can be either Beginner, Intermediate or Expert, and each difficulty has it's own class. If I initiate my 3 CPU players at the beginning of my 'Window' class (below), the program runs fine.
In Window.h
public:
Window(QWidget *parent = 0);
Intermediate *cpu1;
Beginner *cpu2;
Intermediate *cpu3;
In Window.cpp
Window::Window(QWidget *parent):QDialog(parent) {
cpu1 = new Intermediate;
cpu2 = new Beginner;
cpu3 = new Intermediate;
}
However I want the user to be able to select the CPU difficulties at the beginning of the game, so I now have a function within 'Window' that creates the objects. As soon as I call this function the game freezes and I get an error message pop up saying telling me the program has ended unexpectedly.
void Window:: startGame(){
cpu1 = new Intermediate;
cpu2 = new Beginner;
cpu3 = new Intermediate;
}
If anyone would be able to explain to me what is going on and what I can do to get around this that would be great.
Intermediate.cpp (Beginner.cpp is almost identical)
#include "intermediate.h"
Intermediate::Intermediate()
{
tilePlaced = false;
skipGo = false;
}
void Intermediate::findDoubles(int a[7][2]){
for(int i = 0; i < 7; i++){ // Creates new doubles list after each go.
doublesList[i] = 0;
}
for(int i = 0; i < 7; i++){ // Creates a list of doubles
if ((a[i][0] == a[i][1]) && (a[i][0] != 7)){
doublesList[a[i][0]] = 1;
}
}
}
bool Intermediate::addDomino(){} // Function that finds best domino to replace and returns bool
if(tilePlaced == false){
pass++;
text += "\nPassed turn";
return false;
}
else{
pass = 0;
text += QString("\nPlaced [%1 : %2]").arg(a).arg(b);
return true;
}
}
One way to start would be to narrow down which class is causing the fault. Does it work if they are all Beginner, or if they are all Intermediate? If so then the other one is causing the problem.
Related
When returning a ship to the port, speed becomes 0.0 and user inputs shield and fuel.
–If fuel is 0.0, the ship gets destroyed
–Ships still in the priority_queue take 10 shield damage and lose 15 fuel
–If shield or fuel become less than 0.0, the ship gets destroyed
Trying to implement these instructions for my final project. The ships are pointer types and they are in a priority queue named 'battlefield'. The ships also exist in a list of pointers called 'port'. I'm trying to destroy the ships that receive lethal damage but when I try to show them, the Qt program crashes and I get bad_alloc error. This is the last thing I have to do for my project :(
Important code blocks from various files:
I already tried to delete the ships from the port, also tried directly deleting them from the port but the priority_queue gets messed up.
class Civilization {
string name;
int x;
int y;
list<Villager> villagers;
list<Ship*> port;
priority_queue<Ship*, vector<Ship*>, Ship::comp> battle;
}
void Civilization::damageShips()
{
priority_queue<Ship*, vector<Ship*>, Ship::comp> copy = battle;
Ship *s = battle.top();
s->setSpeed(0.0);
while(!copy.empty()) {
Ship *s = copy.top();
s->setShield(s->getShield() - 10);
s->setFuel(s->getFuel() - 15);
copy.pop();
}
priority_queue<Ship*, vector<Ship*>, Ship::comp> temp;
while(!copy.empty()) {
Ship *s = copy.top();
string id = s->getId();
if (s->getShield() > 0 && s->getFuel() > 0) {
temp.push(s);
} else
deleteShip(id);
copy.pop();
}
battle = temp;
battle.pop();
}
void battlefielddisplay::setCivilization(Civilization *civilizaition)
{
size_t size = civilizaition->battlefieldSize();
ui->battlefield_table->setRowCount(int(size));
Civilization &c = *civilizaition;
priority_queue<Ship*, vector<Ship*>, Ship::comp> copy = c.getBattlefield();
int cnt = 0;
while(!copy.empty()) {
Ship *s = copy.top();
QString id = QString::fromStdString(s->getId());
QString fuel = QString::number(s->getFuel());
QString speed = QString::number(s->getSpeed());
QString shield = QString::number(s->getShield());
QString warriors = QString::number(s->size());
QTableWidgetItem *idItem = new QTableWidgetItem(id);
QTableWidgetItem *fuelItem = new QTableWidgetItem(fuel);
QTableWidgetItem *speedItem = new QTableWidgetItem(speed);
QTableWidgetItem *shieldItem = new QTableWidgetItem(shield);
QTableWidgetItem *warriorsItem = new QTableWidgetItem(warriors);
ui->battlefield_table->setItem(cnt, 0, idItem);
ui->battlefield_table->setItem(cnt, 1, fuelItem);
ui->battlefield_table->setItem(cnt, 2, speedItem);
ui->battlefield_table->setItem(cnt, 3, shieldItem);
ui->battlefield_table->setItem(cnt, 4, warriorsItem);
cnt++;
copy.pop();
}
}
void MainWindow::on_battle_remove_ship_clicked()
{
if (flag) {
Civilization* c = videogame.searchCivilization(ui->civilization_search_input->text().toStdString());
double shield = ui->shield_battle_remove->value();
double fuel = ui->fuel_battle_remove->value();
Ship *s = c->getBattleShip();
s->setSpeed(0.0);
s->setShield(shield);
s->setFuel(fuel);
c->damageShips();
qDebug() << "[✔]" << "Removed ship from battlefield";
} else
QMessageBox::information(this, "Error", "Civilization not found");
}
bool Civilization::deleteShip(string &id)
{
bool found = false;
for(size_t i(0); i < shipSize(); ++i) {
auto it = port.begin();
advance(it, i);
auto x = *it;
if (x->getId() == id) {
port.erase(it);
delete x;
--i;
found = true;
}
}
return found;
}
The main problem I see is that you delete the objects without removing the pointers from the container. You are iterating the same container multiple times and trying to access the deleted objects.
An additional problem is that you have multiple copies of the same queue so even removing the pointer from the main container may cause problems.
Try to reconsider the algorithm paying special attention to the life time of the objects. For example you may have a lazy deletion: instead of deleting just mark the objects as those that shall be deleted later. You may have a cleanup at the end of your function.
I'm using custom classes to manage a vending machine. I can't figure out why it keeps throwing a stack overflow error. There are two versions to my program, the first is a basic test to see whether the classes etc work, by pre-defining certain variables. The second version is what it should be like, where the variables in question can change each time the program is ran (depending on user input).
If anyone can suggest ways of avoiding this recursion, or stack overflow, I'd great. Below is the code for the three classes involved;
class Filling
{
protected:
vector<Filling*> selection;
string fillingChosen;
public:
virtual float cost()
{
return 0;
}
virtual ~Filling(void)
{
//needs to be virtual in order to ensure Condiment destructor is called via Beverage pointer
}
};
class CondimentDecorator : public Filling
{
public:
Filling* filling;
void addToPancake(Filling* customerFilling)
{
filling = customerFilling;
}
~CondimentDecorator(void)
{
delete filling;
}
};
class Frosted : public CondimentDecorator
{
float cost()
{ //ERROR IS HERE//
return (.3 + filling->cost());
}
};
Below is the code used to call the above 'cost' function;
void displayCost(Filling* selectedFilling)
{
cout << selectedFilling->cost() << endl;
}
Below is part of the code that initiates it all (main method);
Filling* currentPancake = NULL;
bool invalid = true;
do
{
int selection = makeSelectionScreen(money, currentStock, thisState);
invalid = false;
if (selection == 1)
{
currentPancake = new ChocolateFilling;
}
else if...
.
.
.
.
else
invalid = true;
} while (invalid);
bool makingSelection = true;
CondimentDecorator* currentCondiment = NULL;
do
{
int coatingSelection = makeCoatingSelectionScreen(money, currentStock, thisState);
if (coatingSelection == 1)
currentCondiment = new Frosted;
else if (coatingSelection == 2)...
.
.
.
else if (coatingSelection == 0)
makingSelection = false;
currentCondiment = thisSelection;
currentCondiment->addToPancake(currentPancake);
currentPancake = currentCondiment;
displayCost(currentPancake);
//Below is the code that DOES work, however it is merely meant to be a test. The
//above code is what is needed to work, however keeps causing stack overflows
//and I'm uncertain as to why one version works fine and the other doesn't
/*currentCondiment = new Frosted;
currentCondiment->addToPancake(currentPancake);
currentPancake = currentCondiment;
displayCost(currentPancake);
currentCondiment = new Wildlicious;
currentCondiment->addToPancake(currentPancake);
currentPancake = currentCondiment;
displayCost(currentPancake);*/
} while (makingSelection);
displayCost(currentPancake);
delete currentPancake;
The infinite recursion happens when you call displayCostwith a Frosted whose filling is a Frosted as well. And that happens right here:
currentCondiment->addToPancake(currentPancake);
currentPancake = currentCondiment;
displayCost(currentPancake);
You set the filling of currentCondiment to currentPancake, then call displayCost with currentCondiment.
In the process you also leak the memory that was originally assigned to currentPancake.
Btw currentCondiment = thisSelection; also leaks memory.
Idea: Use smart pointers like std::unique_ptr to get rid of the leaks.
I have a problem caused by this code:
char KernelFS::mount(Partition* part) {
WaitForSingleObject(mutexFS,INFINITE);
int pos;
for(pos=0; pos<26; pos++)
if(mountedPartitions[pos] == 0)
break;
if(pos < 26) {
mountedPartitions[pos] = part;
bitVectors[pos] = new BitVector(part);
fileEvidention[pos] = new ListHandler();
openedFiles[pos] = 0;
forbidOpening[pos] = false;
ReleaseMutex(mutexFS);
return intToChar(pos);
}
else {
ReleaseMutex(mutexFS);
return '0';
}
}
and
char KernelFS::format(char part){
WaitForSingleObject(mutexFS,INFINITE);
forbidOpening[charToInt(part)] = true;
ReleaseMutex(mutexFS);
while(openedFiles[charToInt(part)]>0)
WaitForSingleObject(unmountSem,INFINITE);
WaitForSingleObject(mutexFS,INFINITE);
// write fresh bit vector to cluster 0 of partition
bitVectors[charToInt(part)]->formatBitVector();
openedFiles[charToInt(part)] = 0;
forbidOpening[charToInt(part)] = false;
delete fileEvidention; //!!***!!
fileEvidention[charToInt(part)] = new ListHandler();
// some other stuff, irrelevant
ReleaseMutex(mutexFS);
return 1;
}
There are 3 thread executing, 1 is blocked and two are running through this code;
they first call mount, then format (each has its own argument Partition object, p1 and p2).
The first time mount is called, it always goes through - then there is an assertion failure at random during one of the next calls of mount/format by any of the two running threads.
Usually, it fails during thread 1 - it calls mount(..) completes it, then calls format(...) and fails around:
delete fileEvidention[charToInt(pos)];
(in debug mode, when I reach this instruction, even if I try to go into with F11, there is an assertion failure)
In case it matters... this is the initialization:
char KernelFS::firstLetter = 'A'; // 'A' = 65
Partition* KernelFS::mountedPartitions[26] = {0}; // init. no partitions are mounted
BitVector* KernelFS::bitVectors[26] = {0}; // init. no partitions are mounted
bool KernelFS::forbidOpening[26] = {false};
long KernelFS::openedFiles[26] = {0};
ListHandler* KernelFS::fileEvidention[26] = {0};
HANDLE KernelFS::mutexFS = CreateMutex(0,0,0);
HANDLE KernelFS::unmountSem = CreateSemaphore(0,0,INFINITE,0);
I have never had this error before, I have no idea how to debug this nor what could cause it.
Thanks for the help, in advance.
EDIT:
when i remove the marked line of code (and ignore the memory leak) there is no assertion failure. What is this witchcraft ?
! :)
Solved. should be
delete fileEvidention[charToInt(part)];
......
Is there a way to update the number of joysticks plugged in at run-time other than constantly calling remove_joystick() then install_joystick? This proves to be extremely slow (goes from 60 FPS to around 5).
Allegro 4.2 answers only please...
void Joystick::Update() {
//If joystick input was lost, attempt to reacquire.
if(GetNumJoysticks() == 0) {
throw InputNotAvailableException("Joystick");
}
//If all joysticks were deleted remove input and do nothing.
if(_numjoysticks == 0) {
remove_joystick();
return;
}
//Update state information
if(poll_joystick() < 0) {
throw InputNotAvailableException("Joystick");
}
for(int i = 0; i < _numButtons; ++i) {
_prevButtons[i].b = _curButtons[i].b;
_prevButtons[i].name = _curButtons[i].name;
_curButtons[i].b = joy[_joyNumber].button[i].b;
_curButtons[i].name = joy[_joyNumber].button[i].name;
}
for(int i = 0; i < _numSticks; ++i) {
for(int j = 0; j < joy[_joyNumber].stick[i].num_axis; ++j) {
_prevSticks[i].axis[j].name = _curSticks[i].axis[j].name;
_prevSticks[i].axis[j].pos = _curSticks[i].axis[j].pos;
_prevSticks[i].axis[j].d1 = _curSticks[i].axis[j].d1;
_prevSticks[i].axis[j].d2 = _curSticks[i].axis[j].d2;
_curSticks[i].axis[j].name = joy[_joyNumber].stick[i].axis[j].name;
_curSticks[i].axis[j].pos = joy[_joyNumber].stick[i].axis[j].pos;
_curSticks[i].axis[j].d1 = joy[_joyNumber].stick[i].axis[j].d1;
_curSticks[i].axis[j].d2 = joy[_joyNumber].stick[i].axis[j].d2;
}
_prevSticks[i].flags = _curSticks[i].flags;
_prevSticks[i].name = _curSticks[i].name;
_curSticks[i].flags = joy[_joyNumber].stick[i].flags;
_curSticks[i].name = joy[_joyNumber].stick[i].name;
}
}
int Joystick::GetNumJoysticks() {
remove_joystick();
if(install_joystick(JOY_TYPE_DIRECTX)) {
return 0;
}
return (num_joysticks);
}
The 4.x series does not. The 5.x series does.
You'll have to either listen for native OS events using custom platform specific code (assuming such things exist) and only call the Allegro deinit/init functions when a change is detected, or require the user to initiate joystick refresh manually.
Under Linux, you could inotify_add_watch() /dev/input to check for changes. Looking at the 4.4 Allegro code, looks like you'd want to call the Win32 functions joyGetNumDevs() and joyGetPos(). Something like:
int WIN_MAX_JOYSTICKS = joyGetNumDevs(); // this should never change
JOYINFO ji;
int pluggedin_count = 0;
for (int i = 0; i < WIN_MAX_JOYSTICKS; ++i)
if (joyGetPos(i, &ji) == JOYERR_NOERROR) ++pluggedin_count;
if (pluggedin_count != last_pluggedin_count) /* reinit Allegro */
You'd have to do that every N seconds.
Those joy* functions are Windows functions, so read MSDN docs to learn how to use them.
For some odd reason, my application likes to break on me when I switch to release and run it outside of my debugger. Here's what works for me, and here's what doesn't
(Qt Creator is the IDE)
Debugging with debug configuration - ok
Running with debug configuration - ok
Debugging with release configuration - ok
Running with release configuration - application crash
My UI is one project, and the core for some stuff as a separate dependency. On Windows (compiling with MSVCC), I hit a menu button, which eventually calls down to a function. In that function, the app breaks on adding a new element to a vector. e.g:
str *x = new str();
str *y = new str();
/* ...set some of x & y's members... */
vector.push_back(x); // works fine
vector.push_back(y); // causes crash
If I comment out the line vector.push_back(y);, the app continues no problem until the app leaves the event scope (i.e. the end of OnMenuButtonClick). On OS X, it's similar to the issue of adding an element to a vector, except I have:
std::vector<foo *> SomeFunction()
{
std::vector<foo *> returningVector;
/* do stuff */
std::vector<foo *> goo = GetFooObjects();
for (int i = 0; i < goo.size(); i++)
{
returningVector.push_back(goo[i]); // breaks here
}
}
So what are some causes of this strange behavior without a debugger attached and not under debug configuration? I've checked to make sure all of my variables are initialized, so I'm stumped. If you want to view the code above, the first part can be located here, and the second part here. Please forgive anything you see as "bad", and if you have suggestions that you just can't contain, then please do message me on GitHub.
Edit:
I looked more into it, and found out exactly what's causing the problem, but don't know how to fix it. This is the function where my app crashes (on OS X):
vector<Drive *> Drive::GetFATXDrives( bool HardDisks )
{
vector<Drive *> Return;
if (HardDisks)
{
vector<DISK_DRIVE_INFORMATION> Disks = GetPhysicalDisks();
for (int i = 0; i < (int)Disks.size(); i++)
{
DISK_DRIVE_INFORMATION ddi = Disks.at(i);
// First, try reading the disk way
Streams::xDeviceStream* DS = NULL;
try
{
char path[0x200] = {0};
wcstombs(path, ddi.Path, wcslen(ddi.Path));
DS = new Streams::xDeviceStream(ddi.Path);
}
catch (xException& e)
{
continue;
}
if (DS == NULL || DS->Length() == 0 || DS->Length() < HddOffsets::Data)
{
// Disk is not of valid length
continue;
}
DS->SetPosition(HddOffsets::Data);
// Read the FATX partition magic
int Magic = DS->ReadInt32();
// Close the stream
DS->Close();
// Compare the magic we read to the *actual* FATX magic
if (Magic == FatxMagic)
{
Drive *d = new Drive(Disks.at(i).Path, Disks.at(i).FriendlyName, false);
Return.push_back(d);
}
}
}
vector<Drive *> LogicalDisks = GetLogicalPartitions();
for (int i = 0; i < (int)LogicalDisks.size(); i++)
{
Return.push_back(LogicalDisks.at(i));
}
return Return;
}
If I change if (HardDisks) to if (HardDisks = false), the app works just fine. So, I looked into that scope and discovered that after vector<DISK_DRIVE_INFORMATION> Disks = GetPhysicalDisks();, the heap gets corrupt or something like that. I noticed this because in the debugger, after that function is called, my HardDisks bool changes to "false", which wasn't what it was before.
Here is GetPhysicalDisks:
vector<Drive::DISK_DRIVE_INFORMATION> Drive::GetPhysicalDisks( void )
{
// RIGHT AFTER this vector is initialized, everything goes to hell
vector<Drive::DISK_DRIVE_INFORMATION> ReturnVector;
DIR *dir;
dirent *ent;
dir = opendir("/dev/");
if (dir != NULL)
{
// Read the shit
while ((ent = readdir(dir)) != NULL)
{
// Check the directory name, and if it starts with "disk" then keep it!
QRegExp exp("disk*");
exp.setPatternSyntax(QRegExp::Wildcard);
exp.setCaseSensitivity(Qt::CaseInsensitive);
if (exp.exactMatch(ent->d_name))
{
DISK_DRIVE_INFORMATION curdir;
memset(curdir.FriendlyName, 0, sizeof(curdir.FriendlyName));
memset(curdir.Path, 0, sizeof(curdir.Path));
char diskPath[0x50] = {0};
sprintf(diskPath, "/dev/r%s", ent->d_name);
mbstowcs(curdir.Path, diskPath, strlen(diskPath));
int device;
if ((device = open(diskPath, O_RDONLY)) > 0)
{
#ifdef __linux
hd_driveid hd;
if (!ioctl(device, HDIO_GET_IDENTITY, &hd))
{
swprintf(curdir.FriendlyName, strlen(hd) * 2, L"%hs", hd.model);
}
#elif defined __APPLE__
mbstowcs(curdir.FriendlyName, ent->d_name, strlen(ent->d_name));
#endif
ReturnVector.push_back(curdir);
}
}
}
}
return ReturnVector;
}
While this isn't a real answer as to what happened, I did find a way to fix the problem. Looking at my edit above, I edited my Drive::GetFATXDrives function like so:
vector<Drive *> Drive::GetFATXDrives( bool HardDisks )
{
// Initialize Disks vector up here
vector<DISK_DRIVE_INFORMATION> Disks;
// Call the function to get the hard disks
if (HardDisks)
Drive::GetPhysicalDisks(Disks);
vector<Drive *> ReturnVector;
if (HardDisks)
{
Streams::xDeviceStream* DS = NULL;
for (int i = 0; i < (int)Disks.size(); i++)
{
/* ... */
}
if (DS)
{
DS->Close();
delete DS;
}
}
vector<Drive *> LogicalDisks = GetLogicalPartitions();
for (int i = 0; i < LogicalDisks.size(); i++)
{
ReturnVector.push_back(LogicalDisks[i]);
}
return ReturnVector;
}
And my Drive::GetPhysicalDisks function now takes a vector<DISK_DRIVE_INFORMATION> reference instead of returning one. Seemed to make my program work just fine after that.