quakeforge/include/QF/alloc.h

99 lines
2.6 KiB
C

/*
alloc.h
High-tide allocator.
Copyright (C) 2012 Bill Currie <bill@taniwha.org>
Author: Bill Currie <bill@taniwha.org>
Date: 2012/12/06
This program is free software; you can redistribute it and/or
modify it 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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifndef __QF_alloc_h
#define __QF_alloc_h
#include <stdlib.h>
#include <string.h>
/** \defgroup alloc High-tide allocator.
\ingroup utils
*/
//@{
#ifndef DEBUG_QF_MEMORY
/** High-tide structure allocator for use in linked lists.
Using a free-list with the name of \c NAME_freelist, return a single
element.
The type of the element must be a structure with a field named \c next.
When the free-list is empty, memory is claimed from the system in blocks.
Elements may be returned to the pool by linking them into the free-list.
\param s The number of structures in the block.
\param t The structure type.
\param n The \c NAME portion of the \c NAME_freelist free-list.
\param v The destination of the pointer to the allocated
element. The contents of the allocated element will be
memset to 0.
\hideinitializer
*/
#define ALLOC(s, t, n, v) \
do { \
if (!n##_freelist) { \
int i; \
n##_freelist = malloc ((s) * sizeof (t)); \
for (i = 0; i < (s) - 1; i++) \
n##_freelist[i].next = &n##_freelist[i + 1];\
n##_freelist[i].next = 0; \
} \
v = n##_freelist; \
n##_freelist = n##_freelist->next; \
memset (v, 0, sizeof (*v)); \
} while (0)
/** Free a block allocated by #ALLOC
\param n The \c NAME portion of the \c NAME_freelist free-list.
\param p The pointer to the block to be freed.
\hideinitializer
*/
#define FREE(n, p) \
do { \
p->next = n##_freelist; \
n##_freelist = p; \
} while (0)
#else
#define ALLOC(s, t, n, v) \
do { \
__attribute__((unused)) t **dummy = &n##_freelist; \
v = (t *) calloc (1, sizeof (t)); \
} while (0)
#define FREE(n, p) do { free (p); } while (0)
#endif
//@}
#endif//__QF_alloc_h