1/*
2 *  This program is free software; you can redistribute it and/or modify
3 *  it under the terms of the GNU General Public License version 2.
4 *
5 *  This program is distributed in the hope that it will be useful,
6 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
7 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
8 *  GNU General Public License for more details.
9 *
10 * Test that the state of the shared memory object, including all data
11 * associated with the shared memory object, persists until all mapping
12 * references are gone even if the shared memory object is unlinked and there
13 * is no open reference anymore.
14 *
15 * Steps:
16 *  1. Create a shared memory object, map it and write a string in it.
17 *  2. Close the file descriptor and unlink the object.
18 *  3. Check that the previously written string is always in the mapped memory.
19 */
20
21/* ftruncate was formerly an XOPEN extension. We define _XOPEN_SOURCE here to
22   avoid warning if the implementation does not program ftruncate as a base
23   interface */
24#define _XOPEN_SOURCE 600
25
26#include <stdio.h>
27#include <sys/mman.h>
28#include <sys/stat.h>
29#include <unistd.h>
30#include <string.h>
31#include <fcntl.h>
32#include <errno.h>
33#include "posixtest.h"
34
35#define BUF_SIZE 8
36#define SHM_NAME "posixtest_28-2"
37
38int main(void)
39{
40	int fd;
41	char str[BUF_SIZE] = "qwerty";
42	char *buf;
43
44	fd = shm_open(SHM_NAME, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR);
45	if (fd == -1) {
46		perror("An error occurs when calling shm_open()");
47		return PTS_UNRESOLVED;
48	}
49
50	if (ftruncate(fd, BUF_SIZE) != 0) {
51		perror("An error occurs when calling ftruncate()");
52		shm_unlink(SHM_NAME);
53		return PTS_UNRESOLVED;
54	}
55
56	buf = mmap(NULL, BUF_SIZE, PROT_WRITE | PROT_READ, MAP_SHARED, fd, 0);
57	if (buf == MAP_FAILED) {
58		perror("An error occurs when calling mmap()");
59		shm_unlink(SHM_NAME);
60		return PTS_UNRESOLVED;
61	}
62
63	strcpy(buf, str);
64
65	if (close(fd) != 0) {
66		perror("An error occurs when calling close()");
67		shm_unlink(SHM_NAME);
68		return PTS_UNRESOLVED;
69	}
70
71	if (shm_unlink(SHM_NAME) != 0) {
72		perror("An error occurs when calling shm_unlink()");
73		return PTS_UNRESOLVED;
74	}
75	/* Now, SHM_NAME is unlinked and there are no more open references on
76	   it but a mapping reference remain */
77
78	if (strcmp(buf, str) == 0) {
79		printf("Test PASSED\n");
80		return PTS_PASS;
81	}
82	printf("The content of the shared memory object was removed.\n");
83	return PTS_FAIL;
84}
85