1/*
2 * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16/* Test readlink /proc/self/map_files/... */
17#include <errno.h>
18#include <sys/types.h>
19#include <sys/stat.h>
20#include <fcntl.h>
21#include <stdio.h>
22#include <unistd.h>
23#include <sys/mman.h>
24#include <stdlib.h>
25
26static void pass(const char *fmt, unsigned long a, unsigned long b)
27{
28 char name[64];
29 char buf[64];
30
31 snprintf(name, sizeof(name), fmt, a, b);
32 if (readlink(name, buf, sizeof(buf)) == -1)
33 exit(1);
34}
35
36static void fail(const char *fmt, unsigned long a, unsigned long b)
37{
38 char name[64];
39 char buf[64];
40
41 snprintf(name, sizeof(name), fmt, a, b);
42 if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT)
43 return;
44 exit(1);
45}
46
47int main(void)
48{
49 const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE);
50 void *p;
51 int fd;
52 unsigned long a, b;
53
54 fd = open("/dev/zero", O_RDONLY);
55 if (fd == -1)
56 return 1;
57
58 p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE, fd, 0);
59 if (p == MAP_FAILED)
60 return 1;
61
62 a = (unsigned long)p;
63 b = (unsigned long)p + PAGE_SIZE;
64
65 pass(fmt: "/proc/self/map_files/%lx-%lx", a, b);
66 fail(fmt: "/proc/self/map_files/ %lx-%lx", a, b);
67 fail(fmt: "/proc/self/map_files/%lx -%lx", a, b);
68 fail(fmt: "/proc/self/map_files/%lx- %lx", a, b);
69 fail(fmt: "/proc/self/map_files/%lx-%lx ", a, b);
70 fail(fmt: "/proc/self/map_files/0%lx-%lx", a, b);
71 fail(fmt: "/proc/self/map_files/%lx-0%lx", a, b);
72 if (sizeof(long) == 4) {
73 fail(fmt: "/proc/self/map_files/100000000%lx-%lx", a, b);
74 fail(fmt: "/proc/self/map_files/%lx-100000000%lx", a, b);
75 } else if (sizeof(long) == 8) {
76 fail(fmt: "/proc/self/map_files/10000000000000000%lx-%lx", a, b);
77 fail(fmt: "/proc/self/map_files/%lx-10000000000000000%lx", a, b);
78 } else
79 return 1;
80
81 return 0;
82}
83

source code of linux/tools/testing/selftests/proc/proc-self-map-files-001.c