5 Debugger Implementation Details

The following classes in the PUP framework were used in implementing debugging support in charm.

• class PUP::er - This class is the abstract superclass of all the other classes in the framework. The pup method of a particular class takes a reference to a PUP::er as parameter. This class has methods for dealing with all the basic C++ data types. All these methods are expressed in terms of a generic pure virtual method. Subclasses only need to provide the generic method.

• class PUP::toText - This is a subclass of the PUP::toTextUtil class which is a subclass of the PUP::er class. It copies the data of an object to a C string, including the terminating NULL.

• class PUP::sizerText - This is a subclass of the PUP::toTextUtil class which is a subclass of the PUP::er class. It returns the number of characters including the terminating NULL and is used by the PUP::toText object to allocate space for building the C string.

The code below shows a simple class declaration that includes a pup method.

  class foo {
   private:
    bool isBar;
    int x;
    char y;
    unsigned long z;
    float q[3];
   public:
    void pup(PUP::er &p) {
      p(isBar);
      p(x);p(y);p(z);
      p(q,3);
    }
  };