oscar64/include/opp/slab.h

81 lines
1.1 KiB
C++

#ifndef OPP_SLAB_H
#define OPP_SLAB_H
template<class T, int N>
class slabptr
{
public:
char index;
slabptr(void)
: index(N)
{}
slabptr(char i)
: index(i)
{}
slabptr(const slabptr & i)
: index(i.index)
{}
auto operator-> ();
auto & operator* ();
};
template <class T, int N>
class slab
{
protected:
static __striped T buffer[N];
static char head;
static char next[N];
public:
typedef slabptr<T, N> ptr;
static void init(void);
static auto alloc(void);
static void free(ptr p);
};
template<class T, int N>
inline auto slabptr<T, N>::operator-> ()
{
return slab<T, N>::buffer + index;
}
template<class T, int N>
inline auto & slabptr<T, N>::operator* ()
{
return slab<T, N>::buffer[index];
}
template <class T, int N>
void slab<T, N>::init(void)
{
head = 0;
for(char i=0; i<N; i++)
next[i] = i + 1;
}
template <class T, int N>
auto slab<T, N>::alloc(void)
{
char i = head;
head = next[head];
return slabptr<T, N>(i);
}
template <class T, int N>
void slab<T, N>::free(slabptr<T, N> p)
{
next[p.index] = head;
head = p.index;
}
#endif