1*1514387aSkamil /* $NetBSD: cmd_mapper.c,v 1.1 2019/01/17 20:47:42 kamil Exp $ */
2*1514387aSkamil
3*1514387aSkamil /*-
4*1514387aSkamil * Copyright (c) 2019 The NetBSD Foundation, Inc.
5*1514387aSkamil * All rights reserved.
6*1514387aSkamil *
7*1514387aSkamil * Redistribution and use in source and binary forms, with or without
8*1514387aSkamil * modification, are permitted provided that the following conditions
9*1514387aSkamil * are met:
10*1514387aSkamil * 1. Redistributions of source code must retain the above copyright
11*1514387aSkamil * notice, this list of conditions and the following disclaimer.
12*1514387aSkamil * 2. Redistributions in binary form must reproduce the above copyright
13*1514387aSkamil * notice, this list of conditions and the following disclaimer in the
14*1514387aSkamil * documentation and/or other materials provided with the distribution.
15*1514387aSkamil *
16*1514387aSkamil * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17*1514387aSkamil * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18*1514387aSkamil * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19*1514387aSkamil * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20*1514387aSkamil * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21*1514387aSkamil * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22*1514387aSkamil * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23*1514387aSkamil * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24*1514387aSkamil * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25*1514387aSkamil * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26*1514387aSkamil * POSSIBILITY OF SUCH DAMAGE.
27*1514387aSkamil */
28*1514387aSkamil
29*1514387aSkamil #include <sys/cdefs.h>
30*1514387aSkamil __RCSID("$NetBSD: cmd_mapper.c,v 1.1 2019/01/17 20:47:42 kamil Exp $");
31*1514387aSkamil
32*1514387aSkamil #include <sys/mman.h>
33*1514387aSkamil
34*1514387aSkamil #include <err.h>
35*1514387aSkamil #include <fcntl.h>
36*1514387aSkamil #include <stdio.h>
37*1514387aSkamil #include <stdlib.h>
38*1514387aSkamil #include <unistd.h>
39*1514387aSkamil
40*1514387aSkamil #define _PATH_DEV_MAPPER "/dev/mapper"
41*1514387aSkamil
main(int argc,char ** argv)42*1514387aSkamil int main(int argc, char **argv)
43*1514387aSkamil {
44*1514387aSkamil int devfd;
45*1514387aSkamil char *map = NULL;
46*1514387aSkamil
47*1514387aSkamil if ((devfd = open(_PATH_DEV_MAPPER, O_RDONLY)) == -1)
48*1514387aSkamil err(EXIT_FAILURE, "Cannot open %s", _PATH_DEV_MAPPER);
49*1514387aSkamil
50*1514387aSkamil map = (char *)(mmap(0, sysconf(_SC_PAGESIZE), PROT_READ, MAP_SHARED,
51*1514387aSkamil devfd, 0));
52*1514387aSkamil if (map == MAP_FAILED)
53*1514387aSkamil err(EXIT_FAILURE, "Mapping failed");
54*1514387aSkamil
55*1514387aSkamil printf("Message from device: %s\n",map);
56*1514387aSkamil
57*1514387aSkamil if (munmap(map, sysconf(_SC_PAGESIZE)) == -1)
58*1514387aSkamil err(EXIT_FAILURE, "Unmap failed");
59*1514387aSkamil
60*1514387aSkamil if (close(devfd) == -1)
61*1514387aSkamil err(EXIT_FAILURE, "Cannot close %s", _PATH_DEV_MAPPER);
62*1514387aSkamil
63*1514387aSkamil return EXIT_SUCCESS;
64*1514387aSkamil }
65