should we change free/finalize functions to take double pointers?

[alistairking]

this would make the interface a little more robust in that the caller would give up their reference to the object being free'd.

for example, if i have a pointer, ptr, to corsaro_t and i call corsaro_finalize_output(ptr), the pointer is no longer valid, but i still have it pointing to some invalid memory.

instead, if we made the declaration corsaro_finalize_output(corsaro_t **corsaro), the caller would call the function as: corsaro_finalize_output(&ptr), and when it returned, ptr would point to NULL.