45 lines
2.8 KiB
C
45 lines
2.8 KiB
C
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/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright 2020 Justine Alexandra Roberts Tunney │
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│ │
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│ This program is free software; you can redistribute it and/or modify │
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│ it under the terms of the GNU General Public License as published by │
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│ the Free Software Foundation; version 2 of the License. │
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│ │
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│ This program is distributed in the hope that it will be useful, but │
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│ WITHOUT ANY WARRANTY; without even the implied warranty of │
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│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
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│ General Public License for more details. │
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│ │
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│ You should have received a copy of the GNU General Public License │
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│ along with this program; if not, write to the Free Software │
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│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
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│ 02110-1301 USA │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/mem/mem.h"
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#include "libc/runtime/buffer.h"
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/* TODO(jart): Delete */
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#define kGuard PAGESIZE
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#define kGrain FRAMESIZE
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/**
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* Allocates page-guarded buffer.
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*
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* ┌─────────────────────────────────────┬s─i─g─s─e─g─v┐
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* │ 𝑣₀..𝑣ₙ₋₁ │𝑣ₙ..𝑣ₙ₊₄₀₉₆₋₁│
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* └─────────────────────────────────────┴s─i─g─s─e─g─v┘
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*
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* @param b is metadata object owned by caller, initialized to zero for
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* first call; subsequent calls will resize
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* @param a is alignment requirement in bytes, e.g. 1,2,4,8,16,...
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* @param n is buffer size in bytes
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* @return b->p
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* @see ralloc()
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*/
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void *balloc(struct GuardedBuffer *b, unsigned a, size_t n) {
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return (b->p = memalign(a, n));
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}
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