81 lines
2.2 KiB
C++
81 lines
2.2 KiB
C++
#ifndef __slab_H
|
|
#define __slab_H
|
|
/*
|
|
* Copyright (c) 2008 Picture Elements, Inc.
|
|
* Stephen Williams (steve@icarus.com)
|
|
*
|
|
* This source code is free software; you can redistribute it
|
|
* and/or modify it in source code form under the terms of the GNU
|
|
* General Public License as published by the Free Software
|
|
* Foundation; either version 2 of the License, or (at your option)
|
|
* any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
|
|
*/
|
|
|
|
|
|
template <size_t SLAB_SIZE, size_t CHUNK_COUNT> class slab_t {
|
|
|
|
union item_cell_u {
|
|
item_cell_u*next;
|
|
char space[SLAB_SIZE];
|
|
};
|
|
|
|
public:
|
|
slab_t();
|
|
|
|
void* alloc_slab();
|
|
void free_slab(void*);
|
|
|
|
unsigned long pool;
|
|
|
|
private:
|
|
item_cell_u*heap_;
|
|
item_cell_u initial_chunk_[CHUNK_COUNT];
|
|
};
|
|
|
|
template <size_t SLAB_SIZE, size_t CHUNK_COUNT>
|
|
slab_t<SLAB_SIZE,CHUNK_COUNT>::slab_t()
|
|
{
|
|
pool = CHUNK_COUNT;
|
|
heap_ = initial_chunk_;
|
|
for (unsigned idx = 0 ; idx < CHUNK_COUNT-1 ; idx += 1)
|
|
initial_chunk_[idx].next = initial_chunk_+idx+1;
|
|
|
|
initial_chunk_[CHUNK_COUNT-1].next = 0;
|
|
}
|
|
|
|
template <size_t SLAB_SIZE, size_t CHUNK_COUNT>
|
|
inline void* slab_t<SLAB_SIZE,CHUNK_COUNT>::alloc_slab()
|
|
{
|
|
if (heap_ == 0) {
|
|
item_cell_u*chunk = new item_cell_u[CHUNK_COUNT];
|
|
for (unsigned idx = 0 ; idx < CHUNK_COUNT ; idx += 1) {
|
|
chunk[idx].next = heap_;
|
|
heap_ = chunk+idx;
|
|
}
|
|
pool += CHUNK_COUNT;
|
|
}
|
|
|
|
item_cell_u*cur = heap_;
|
|
heap_ = heap_->next;
|
|
return cur;
|
|
}
|
|
|
|
template <size_t SLAB_SIZE, size_t CHUNK_COUNT>
|
|
inline void slab_t<SLAB_SIZE,CHUNK_COUNT>::free_slab(void*ptr)
|
|
{
|
|
item_cell_u*cur = reinterpret_cast<item_cell_u*> (ptr);
|
|
cur->next = heap_;
|
|
heap_ = cur;
|
|
}
|
|
|
|
#endif
|