/** * $Id$ * * ***** BEGIN GPL LICENSE BLOCK ***** * * 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 the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV. * All rights reserved. * * The Original Code is: all of this file. * * Contributor(s): none yet. * * ***** END GPL LICENSE BLOCK ***** * Efficient memory allocation for lots of similar small chunks. */ #include "MEM_guardedalloc.h" #include "BLI_memarena.h" #include "BLI_linklist.h" struct MemArena { unsigned char *curbuf; int bufsize, cursize; const char *name; int use_calloc; int align; LinkNode *bufs; }; MemArena *BLI_memarena_new(int bufsize, const char *name) { MemArena *ma= MEM_callocN(sizeof(*ma), "memarena"); ma->bufsize= bufsize; ma->align = 8; ma->name= name; return ma; } void BLI_memarena_use_calloc(MemArena *ma) { ma->use_calloc= 1; } void BLI_memarena_use_malloc(MemArena *ma) { ma->use_calloc= 0; } void BLI_memarena_use_align(struct MemArena *ma, int align) { /* align should be a power of two */ ma->align = align; } void BLI_memarena_free(MemArena *ma) { BLI_linklist_free(ma->bufs, (void(*)(void*)) MEM_freeN); MEM_freeN(ma); } /* amt must be power of two */ #define PADUP(num, amt) ((num+(amt-1))&~(amt-1)) void *BLI_memarena_alloc(MemArena *ma, int size) { void *ptr; /* ensure proper alignment by rounding * size up to multiple of 8 */ size= PADUP(size, ma->align); if (size>ma->cursize) { unsigned char *tmp; if(size > ma->bufsize - (ma->align - 1)) { ma->cursize = PADUP(size+1, ma->align); } else ma->cursize = ma->bufsize; if(ma->use_calloc) ma->curbuf= MEM_callocN(ma->cursize, ma->name); else ma->curbuf= MEM_mallocN(ma->cursize, ma->name); BLI_linklist_prepend(&ma->bufs, ma->curbuf); /* align alloc'ed memory (needed if align > 8) */ tmp = (unsigned char*)PADUP( (intptr_t) ma->curbuf, ma->align); ma->cursize -= (tmp - ma->curbuf); ma->curbuf = tmp; } ptr= ma->curbuf; ma->curbuf+= size; ma->cursize-= size; return ptr; }