C++ Automatic Reference Counting
This project intends to simplify memory management in C++, using reference counting.
When allocating memory with the new operator, CPP-ARC automatically adds a few bytes of memory to manage a retain count on the memory area.
Memory can then be retained or released.
An allocation sets the retain count to 1. A retain increments it, and a release decrements it.
When the retain count reaches 0, the memory is freed.
C++ classes are fully compatible with this scheme, as the destructors are called when the memory is freed.
This project also includes a template used to auto-release allocated memory, when it's not used anymore.
Memory allocated with new (primitive types or classes) can be retained or released.
To do so, simply call:
template< typename T > T * CPPARC::retain( T * p );
template< typename T > void CPPARC::release( T * p );
So for instance:
class Point
{
public:
int x;
int y;
};
int main( void )
{
Point * p = new Point();
char * s = new char[ 10 ];
CPPARC::retain( p );
CPPARC::release( p );
// s will be freed here
CPPARC::release( s );
// p will be freed here - destructor will be called
CPPARC::release( p );
return 0;
}
Allocated memory can also be auto-released, when it's not used anymore.
In order to to this, you can use the CPPARC::AutoPointer template class:
class Point
{
public:
int x;
int y;
};
int main( void )
{
CPPARC::AutoPointer< Point > p = new Point();
// Nothing to do here, as the Point object will be automatically freed.
return 0;
}
The AutoPointer template also provides direct access to class members:
class Foo
{
public:
void test( void )
{
std::cout << "hello, world" << std::endl;
}
};
int main( void )
{
CPPARC::AutoPointer< Foo > f = new Foo();
// Will output "hello, world", just as a normal pointer
f->test();
return 0;
}
You can of course use the AutoPointer template for functions/methods with arguments, or as return type:
class Point
{
public:
int x;
int y;
};
CPPARC::AutoPointer< Point > getPoint( void )
{
return new Point();
}
int main( void )
{
CPPARC::AutoPointer< Point > p = getPoint();
// Nothing to do here, memory will be freed automatically.
return 0;
}
CPP-ARC is released under the terms of the Boost Software License - Version 1.0.
Owner: Jean-David Gadina - XS-Labs
Web: www.xs-labs.com
Blog: www.noxeos.com
Twitter: @macmade
GitHub: github.com/macmade
LinkedIn: ch.linkedin.com/in/macmade/
StackOverflow: stackoverflow.com/users/182676/macmade