108 lines
2.8 KiB
C
108 lines
2.8 KiB
C
|
/*-
|
||
|
|
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
|
||
|
|
*
|
||
|
|
* Copyright (c) 2018 Mark Johnston <markj@FreeBSD.org>
|
||
|
|
*
|
||
|
|
* Redistribution and use in source and binary forms, with or without
|
||
|
|
* modification, are permitted provided that the following conditions
|
||
|
|
* are met:
|
||
|
|
* 1. Redistributions of source code must retain the above copyright
|
||
|
|
* notice, this list of conditions and the following disclaimer.
|
||
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
||
|
|
* notice, this list of conditions and the following disclaimer in the
|
||
|
|
* documentation and/or other materials provided with the distribution.
|
||
|
|
*
|
||
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
||
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||
|
|
* SUCH DAMAGE.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <sys/cdefs.h>
|
||
|
|
__FBSDID("$FreeBSD$");
|
||
|
|
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <sys/syscall.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <stdint.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
|
||
|
|
void *__sys_break(char *nsize);
|
||
|
|
|
||
|
|
static uintptr_t curbrk, minbrk;
|
||
|
|
static int curbrk_initted;
|
||
|
|
|
||
|
|
static int
|
||
|
|
initbrk(void)
|
||
|
|
{
|
||
|
|
void *newbrk;
|
||
|
|
|
||
|
|
if (!curbrk_initted) {
|
||
|
|
newbrk = __sys_break(NULL);
|
||
|
|
if (newbrk == (void *)-1)
|
||
|
|
return (-1);
|
||
|
|
curbrk = minbrk = (uintptr_t)newbrk;
|
||
|
|
curbrk_initted = 1;
|
||
|
|
}
|
||
|
|
return (0);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void *
|
||
|
|
mvbrk(void *addr)
|
||
|
|
{
|
||
|
|
uintptr_t oldbrk;
|
||
|
|
|
||
|
|
if ((uintptr_t)addr < minbrk) {
|
||
|
|
/* Emulate legacy error handling in the syscall. */
|
||
|
|
errno = EINVAL;
|
||
|
|
return ((void *)-1);
|
||
|
|
}
|
||
|
|
if (__sys_break(addr) == (void *)-1)
|
||
|
|
return ((void *)-1);
|
||
|
|
oldbrk = curbrk;
|
||
|
|
curbrk = (uintptr_t)addr;
|
||
|
|
return ((void *)oldbrk);
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
brk(const void *addr)
|
||
|
|
{
|
||
|
|
|
||
|
|
if (initbrk() == -1)
|
||
|
|
return (-1);
|
||
|
|
if ((uintptr_t)addr < minbrk)
|
||
|
|
addr = (void *)minbrk;
|
||
|
|
return (mvbrk(__DECONST(void *, addr)) == (void *)-1 ? -1 : 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
_brk(const void *addr)
|
||
|
|
{
|
||
|
|
|
||
|
|
if (initbrk() == -1)
|
||
|
|
return (-1);
|
||
|
|
return (mvbrk(__DECONST(void *, addr)) == (void *)-1 ? -1 : 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
void *
|
||
|
|
sbrk(intptr_t incr)
|
||
|
|
{
|
||
|
|
|
||
|
|
if (initbrk() == -1)
|
||
|
|
return ((void *)-1);
|
||
|
|
if ((incr > 0 && curbrk + incr < curbrk) ||
|
||
|
|
(incr < 0 && curbrk + incr > curbrk)) {
|
||
|
|
/* Emulate legacy error handling in the syscall. */
|
||
|
|
errno = EINVAL;
|
||
|
|
return ((void *)-1);
|
||
|
|
}
|
||
|
|
return (mvbrk((void *)(curbrk + incr)));
|
||
|
|
}
|