1 /* 2 * Copyright (C) 1998-2000 Netscape Communications Corporation. 3 * Copyright (C) 2003-6 Apple Computer 4 * 5 * Other contributors: 6 * Nick Blievers <nickb (at) adacel.com.au> 7 * Jeff Hostetler <jeff (at) nerdone.com> 8 * Tom Rini <trini (at) kernel.crashing.org> 9 * Raffaele Sena <raff (at) netwinder.org> 10 * 11 * This library is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU Lesser General Public 13 * License as published by the Free Software Foundation; either 14 * version 2.1 of the License, or (at your option) any later version. 15 * 16 * This library is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 19 * Lesser General Public License for more details. 20 * 21 * You should have received a copy of the GNU Lesser General Public 22 * License along with this library; if not, write to the Free Software 23 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 24 * 25 * Alternatively, the contents of this file may be used under the terms 26 * of either the Mozilla Public License Version 1.1, found at 27 * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public 28 * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html 29 * (the "GPL"), in which case the provisions of the MPL or the GPL are 30 * applicable instead of those above. If you wish to allow use of your 31 * version of this file only under the terms of one of those two 32 * licenses (the MPL or the GPL) and not to allow others to use your 33 * version of this file under the LGPL, indicate your decision by 34 * deletingthe provisions above and replace them with the notice and 35 * other provisions required by the MPL or the GPL, as the case may be. 36 * If you do not delete the provisions above, a recipient may use your 37 * version of this file under any of the LGPL, the MPL or the GPL. 38 */ 39 40 #ifndef Arena_h 41 #define Arena_h 42 43 #define ARENA_ALIGN_MASK 3 44 45 namespace WebCore { 46 47 typedef unsigned long uword; 48 49 struct Arena { 50 Arena* next; // next arena 51 uword base; // aligned base address 52 uword limit; // end of arena (1+last byte) 53 uword avail; // points to next available byte in arena 54 }; 55 56 struct ArenaPool { 57 Arena first; // first arena in pool list. 58 Arena* current; // current arena. 59 unsigned int arenasize; 60 uword mask; // Mask (power-of-2 - 1) 61 }; 62 63 void InitArenaPool(ArenaPool *pool, const char *name, 64 unsigned int size, unsigned int align); 65 void FinishArenaPool(ArenaPool *pool); 66 void FreeArenaPool(ArenaPool *pool); 67 void* ArenaAllocate(ArenaPool *pool, unsigned int nb); 68 69 #define ARENA_ALIGN(pool, n) (((uword)(n) + ARENA_ALIGN_MASK) & ~ARENA_ALIGN_MASK) 70 #define INIT_ARENA_POOL(pool, name, size) \ 71 InitArenaPool(pool, name, size, ARENA_ALIGN_MASK + 1) 72 73 #define ARENA_ALLOCATE(p, pool, nb) \ 74 Arena *_a = (pool)->current; \ 75 unsigned int _nb = ARENA_ALIGN(pool, nb); \ 76 uword _p = _a->avail; \ 77 uword _q = _p + _nb; \ 78 if (_q > _a->limit) \ 79 _p = (uword)ArenaAllocate(pool, _nb); \ 80 else \ 81 _a->avail = _q; \ 82 p = (void *)_p; 83 84 #define ARENA_GROW(p, pool, size, incr) \ 85 Arena *_a = (pool)->current; \ 86 unsigned int _incr = ARENA_ALIGN(pool, incr); \ 87 uword _p = _a->avail; \ 88 uword _q = _p + _incr; \ 89 if (_p == (uword)(p) + ARENA_ALIGN(pool, size) && \ 90 _q <= _a->limit) { \ 91 _a->avail = _q; \ 92 } else { \ 93 p = ArenaGrow(pool, p, size, incr); \ 94 } 95 96 #define ARENA_MARK(pool) ((void *) (pool)->current->avail) 97 #define UPTRDIFF(p,q) ((uword)(p) - (uword)(q)) 98 99 #ifdef DEBUG 100 #define FREE_PATTERN 0xDA 101 #define CLEAR_UNUSED(a) ASSERT((a)->avail <= (a)->limit); \ 102 memset((void*)(a)->avail, FREE_PATTERN, \ 103 (a)->limit - (a)->avail) 104 #define CLEAR_ARENA(a) memset((void*)(a), FREE_PATTERN, \ 105 (a)->limit - (uword)(a)) 106 #else 107 #define CLEAR_UNUSED(a) 108 #define CLEAR_ARENA(a) 109 #endif 110 111 #define ARENA_RELEASE(pool, mark) \ 112 char *_m = (char *)(mark); \ 113 Arena *_a = (pool)->current; \ 114 if (UPTRDIFF(_m, _a->base) <= UPTRDIFF(_a->avail, _a->base)) { \ 115 _a->avail = (uword)ARENA_ALIGN(pool, _m); \ 116 CLEAR_UNUSED(_a); \ 117 } else { \ 118 ArenaRelease(pool, _m); \ 119 } 120 121 #define ARENA_DESTROY(pool, a, pnext) \ 122 if ((pool)->current == (a)) (pool)->current = &(pool)->first; \ 123 *(pnext) = (a)->next; \ 124 CLEAR_ARENA(a); \ 125 fastFree(a); \ 126 (a) = 0; 127 128 #ifdef ANDROID_INSTRUMENT 129 size_t ReportPoolSize(const ArenaPool* pool); 130 #endif 131 132 } 133 134 #endif 135