Receiving memory leaks when editing strings - c++

Question

string Player::CalcAsteroid(int _mass)
{
vector<BaseObject*>* tempObjects = GameState::GetObjects();
asteroid = "";
SetRadius(_mass / 100);
if (_mass < 100)
SetRadius(1);
///////////////////////////////////////////////
// Nested for loops to draw a circle (asteroid)
///////////////////////////////////////////////
// x^2/a^2 + y^2/b^2 = 1
Player* p = dynamic_cast<Player*> ((*tempObjects)[0]);
int asteroidRadius = p->GetRadius();
double consoleRatio = 4.0 / 3.0; // Console characters do not have uniform H and W, so lets store the console ratio (4:3)
double a = consoleRatio*asteroidRadius; // The width is shorter than the height, so we'll multiply the ratio to the X radius (a)
double b = asteroidRadius; // The height need not change from the init radius
// Loop though each row...
for (int y = (int)-asteroidRadius; y <= asteroidRadius; y++)
{
// and each column.
for (int x = (int)floor(-consoleRatio*asteroidRadius); x <= consoleRatio*asteroidRadius; x++)
{
double d = (x / a)*(x / a) + (y / b)*(y / b); // Equation of a circle (see above)
if (d > 0.90 && d < 1.1)
{
asteroid += (char)178; // The solid border (using gradient ASCII code)
}
//else if (d <= 1.1)
//{
//asteroid += 176; // The fill interior
//}
else
{
asteroid += " ";
}
}
asteroid += '\n';
}
asteroid.replace(asteroid.size() / 2 - (name.size() / 2), name.size(), name); // Putting the name of the player in the center of the asteroid.
return asteroid;
}
So I am attempting to re-size the player's object (an asteroid) in console. However I seem to be getting memory leaks, a ton actually. Each seems to be related to this function call.
SetPicture(CalcAsteroid(GetMass()).c_str());
The definition of which being here
void SetPicture(const char * const _picture){ picture = _strdup(_picture);CalcWH(); }
CalcWH(); simply calculates the width and height of the image in characters for collision data.
Dropbox link for full solution.
Thank you all in advance! Let me know if there is anything I can do to make my question more clear or whether or not I have enough information. I'm new to this site and I wish to follow good question habits.

Answer 1

The reason for a memory leak is the usage of _strdup. This allocates memory for the new string. It is your responsibility to free the memory using free somewhere in your code. According to the code you posted, you are not calling free anywhere.
https://msdn.microsoft.com/en-us/library/y471khhc.aspx
As noted by the above link:
The _strdup function calls malloc to allocate storage space for a copy of strSource and then copies strSource to the allocated space.
My advice is to get out of the business of calling _strdup, and just use a std::string. There is little reason for a C++ application to use functions such as strdup.