Visit all areas and blocks in a heap.
The heap to visit.
If true visits all allocated blocks, otherwise visitor is only called for every heap area.
This function is called for every area in the heap (with block as NULL). If visit_all_blocks is true, visitor is also called for every allocated block in every area (with block!=NULL). return false from this function to stop visiting early.
Extra argument passed to visitor.
true if all areas and blocks were visited.