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/*
* This file and its contents are supplied under the terms of the
* Common Development and Distribution License ("CDDL"), version 1.0.
* You may only use this file in accordance with the terms of version
* 1.0 of the CDDL.
*
* A full copy of the text of the CDDL should have accompanied this
* source. A copy of the CDDL is also available via the Internet at
* http://www.illumos.org/license/CDDL.
*/
/*
* Copyright (c) 2015, Joyent, Inc.
*/
/*
* Verify that using MC_INHERIT_ZERO works just fine when applied to an entire
* region that then gets split in half, hence creating new segments.
*/
#include <sys/types.h>
#include <unistd.h>
#include <assert.h>
#include <sys/mman.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <wait.h>
int
main(void)
{
void *buf;
pid_t child;
int ret, i;
siginfo_t info;
uint8_t *ubuf;
size_t mapsz = sysconf(_SC_PAGESIZE) * 8;
size_t spltsz = sysconf(_SC_PAGESIZE) * 4;
size_t spltoff = sysconf(_SC_PAGESIZE) * 2;
buf = mmap(NULL, mapsz, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON, -1, 0);
assert(buf != MAP_FAILED);
memset(buf, 'a', mapsz);
ret = memcntl(buf, mapsz, MC_INHERIT_ZERO, 0, 0, 0);
assert(ret == 0);
ret = munmap(buf + spltoff, spltsz);
assert(ret == 0);
child = fork();
if (child == 0) {
ubuf = buf;
for (i = 0; i < spltoff; i++)
assert(ubuf[i] == 0);
for (i = spltoff + spltsz; i < mapsz; i++)
assert(ubuf[i] == 0);
exit(0);
}
assert(child != -1);
do {
ret = waitid(P_PID, child, &info, WEXITED);
} while (ret == -1 && errno == EINTR);
assert(ret == 0);
assert(info.si_pid == child);
assert(info.si_status == 0);
ubuf = buf;
for (i = 0; i < spltoff; i++)
assert(ubuf[i] == 'a');
for (i = spltoff + spltsz; i < mapsz; i++)
assert(ubuf[i] == 'a');
return (0);
}
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