testing storage_pool

storage_pool.hpp

template<class T>
class storage_pool {

	static const size_t mBlockSize = sizeof(T);
	typedef union freelist_t {char data[mBlockSize];freelist_t* next;} freelist_t;

private:

	int mUsed;
	freelist_t* mFreelist;

public:
	storage_pool()
	: mUsed(0)
	, mFreelist(0) {}

	void add_block(void* block, size_t blocksize) {

		freelist_t* p = (freelist_t*)block;
		freelist_t* q = p;
		for(size_t i=1;i<blocksize/sizeof(freelist_t);i++){
			p->next = &q[i];
			p = p->next;
		}
		p->next = mFreelist;
		mFreelist = (freelist_t*)block;
	}

	bool empty() {
		return mFreelist->next == 0;
	}

	T* malloc() {
		if(empty()){
			return 0;
		}

		T* retval = (T*)&mFreelist->data;
		mFreelist = mFreelist->next;

		mUsed++;
		return retval;
	}

	void free(T* ptr) {

		freelist_t* next = mFreelist->next;
		mFreelist = (freelist_t*)ptr;
		mFreelist->next = next;
		mUsed--;
	}
};