While I was looking at WINGs/memory.c eliminating malloc wrappers, I've found two functions that drew my attention. It was wretain and wrelease. If I'm not mistaken, the original idea was to eliminate all handcrafted reference counting code into one place. This is definitely the Good Thing™. But current implementation just sucks. Using hashtables for storing counters with pointers as a keys is definitely not my way of thinking. And those functions are used only in small number of objects in library, with handcrafted reference counting functions for all other objects.
Let's go into that problem little deeper. WINGs library does have objects. In fact there's at least three kind of objects, with different ways to distinguish types:
I think I'll replace this object's zoo with something better. I came up with the following idea. Two common fields for all object are almost obvious. These are some kind of a type tag, and a reference counter for that object. The best kind of type tag I can think of is a pointer to a structure with pointers to methods as fields. I'll start it with the single destroy field, which if present will handle additional operations needed to destroy an object. This solution may add just a little overhead to some «raw» objects, and no overhead to all others. They're already have something like counter field, type tags or destructor field. This overhead should pay off when I start replacement of PropLists with new objects.
Let's go into that problem little deeper. WINGs library does have objects. In fact there's at least three kind of objects, with different ways to distinguish types:
- «raw» data structures like WMArray, WMBag etc with no way to determine type;
- PropList-wrappers over raw structures with closed set of type tags;
- widgets with open set of type tags, but with rudimentary support for creating new type tags.
I think I'll replace this object's zoo with something better. I came up with the following idea. Two common fields for all object are almost obvious. These are some kind of a type tag, and a reference counter for that object. The best kind of type tag I can think of is a pointer to a structure with pointers to methods as fields. I'll start it with the single destroy field, which if present will handle additional operations needed to destroy an object. This solution may add just a little overhead to some «raw» objects, and no overhead to all others. They're already have something like counter field, type tags or destructor field. This overhead should pay off when I start replacement of PropLists with new objects.
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