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Diffstat (limited to 'WebCore/platform/Arena.h')
| -rw-r--r-- | WebCore/platform/Arena.h | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/WebCore/platform/Arena.h b/WebCore/platform/Arena.h new file mode 100644 index 0000000..336a1cf --- /dev/null +++ b/WebCore/platform/Arena.h @@ -0,0 +1,130 @@ +/* + * Copyright (C) 1998-2000 Netscape Communications Corporation. + * Copyright (C) 2003-6 Apple Computer + * + * Other contributors: + * Nick Blievers <nickb@adacel.com.au> + * Jeff Hostetler <jeff@nerdone.com> + * Tom Rini <trini@kernel.crashing.org> + * Raffaele Sena <raff@netwinder.org> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + * Alternatively, the contents of this file may be used under the terms + * of either the Mozilla Public License Version 1.1, found at + * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public + * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html + * (the "GPL"), in which case the provisions of the MPL or the GPL are + * applicable instead of those above. If you wish to allow use of your + * version of this file only under the terms of one of those two + * licenses (the MPL or the GPL) and not to allow others to use your + * version of this file under the LGPL, indicate your decision by + * deletingthe provisions above and replace them with the notice and + * other provisions required by the MPL or the GPL, as the case may be. + * If you do not delete the provisions above, a recipient may use your + * version of this file under any of the LGPL, the MPL or the GPL. + */ + +#ifndef Arena_h +#define Arena_h + +#define ARENA_ALIGN_MASK 3 + +namespace WebCore { + +typedef unsigned long uword; + +struct Arena { + Arena* next; // next arena + uword base; // aligned base address + uword limit; // end of arena (1+last byte) + uword avail; // points to next available byte in arena +}; + +struct ArenaPool { + Arena first; // first arena in pool list. + Arena* current; // current arena. + unsigned int arenasize; + uword mask; // Mask (power-of-2 - 1) +}; + +void InitArenaPool(ArenaPool *pool, const char *name, + unsigned int size, unsigned int align); +void FinishArenaPool(ArenaPool *pool); +void FreeArenaPool(ArenaPool *pool); +void* ArenaAllocate(ArenaPool *pool, unsigned int nb); + +#define ARENA_ALIGN(pool, n) (((uword)(n) + ARENA_ALIGN_MASK) & ~ARENA_ALIGN_MASK) +#define INIT_ARENA_POOL(pool, name, size) \ + InitArenaPool(pool, name, size, ARENA_ALIGN_MASK + 1) + +#define ARENA_ALLOCATE(p, pool, nb) \ + Arena *_a = (pool)->current; \ + unsigned int _nb = ARENA_ALIGN(pool, nb); \ + uword _p = _a->avail; \ + uword _q = _p + _nb; \ + if (_q > _a->limit) \ + _p = (uword)ArenaAllocate(pool, _nb); \ + else \ + _a->avail = _q; \ + p = (void *)_p; + +#define ARENA_GROW(p, pool, size, incr) \ + Arena *_a = (pool)->current; \ + unsigned int _incr = ARENA_ALIGN(pool, incr); \ + uword _p = _a->avail; \ + uword _q = _p + _incr; \ + if (_p == (uword)(p) + ARENA_ALIGN(pool, size) && \ + _q <= _a->limit) { \ + _a->avail = _q; \ + } else { \ + p = ArenaGrow(pool, p, size, incr); \ + } + +#define ARENA_MARK(pool) ((void *) (pool)->current->avail) +#define UPTRDIFF(p,q) ((uword)(p) - (uword)(q)) + +#ifdef DEBUG +#define FREE_PATTERN 0xDA +#define CLEAR_UNUSED(a) (ASSERT((a)->avail <= (a)->limit), \ + memset((void*)(a)->avail, FREE_PATTERN, \ + (a)->limit - (a)->avail)) +#define CLEAR_ARENA(a) memset((void*)(a), FREE_PATTERN, \ + (a)->limit - (uword)(a)) +#else +#define CLEAR_UNUSED(a) +#define CLEAR_ARENA(a) +#endif + +#define ARENA_RELEASE(pool, mark) \ + char *_m = (char *)(mark); \ + Arena *_a = (pool)->current; \ + if (UPTRDIFF(_m, _a->base) <= UPTRDIFF(_a->avail, _a->base)) { \ + _a->avail = (uword)ARENA_ALIGN(pool, _m); \ + CLEAR_UNUSED(_a); \ + } else { \ + ArenaRelease(pool, _m); \ + } + +#define ARENA_DESTROY(pool, a, pnext) \ + if ((pool)->current == (a)) (pool)->current = &(pool)->first; \ + *(pnext) = (a)->next; \ + CLEAR_ARENA(a); \ + fastFree(a); \ + (a) = 0; + +} + +#endif |