1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
|
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <sys/mman.h>
#include <sys/uio.h>
#include "log.h"
#include "macro.h"
#include "util.h"
#include "sd-memfd.h"
int main(int argc, char *argv[]) {
sd_memfd *m;
char *s, *name;
uint64_t sz;
int r, fd;
FILE *f = NULL;
char buf[3] = {};
struct iovec iov[3] = {};
char bufv[3][3] = {};
log_set_max_level(LOG_DEBUG);
r = sd_memfd_new(&m, NULL);
if (r == -ENOENT)
return EXIT_TEST_SKIP;
assert_se(r >= 0);
assert_se(sd_memfd_get_name(m, &name) >= 0);
log_info("name: %s", name);
free(name);
r = sd_memfd_map(m, 0, 12, (void**) &s);
assert_se(r >= 0);
strcpy(s, "----- world");
r = sd_memfd_set_sealed(m, 1);
assert_se(r == -ETXTBSY);
assert_se(write(sd_memfd_get_fd(m), "he", 2) == 2);
assert_se(write(sd_memfd_get_fd(m), "XXX", 3) == 3);
assert_se(streq(s, "heXXX world"));
/* fix "hello" */
assert_se(lseek(sd_memfd_get_fd(m), 2, SEEK_SET) == 2);
assert_se(write(sd_memfd_get_fd(m), "ll", 2) == 2);
assert_se(sd_memfd_get_file(m, &f) >= 0);
fputc('o', f);
fflush(f);
/* check content */
assert_se(streq(s, "hello world"));
assert_se(munmap(s, 12) == 0);
r = sd_memfd_get_sealed(m);
assert_se(r == 0);
r = sd_memfd_get_size(m, &sz);
assert_se(r >= 0);
assert_se(sz = page_size());
/* truncate it */
r = sd_memfd_set_size(m, 6);
assert_se(r >= 0);
/* get back new value */
r = sd_memfd_get_size(m, &sz);
assert_se(r >= 0);
assert_se(sz == 6);
r = sd_memfd_set_sealed(m, 1);
assert_se(r >= 0);
r = sd_memfd_get_sealed(m);
assert_se(r == 1);
fd = sd_memfd_dup_fd(m);
assert_se(fd >= 0);
sd_memfd_free(m);
/* new sd_memfd, same underlying memfd */
r = sd_memfd_new_from_fd(&m, fd);
assert_se(r >= 0);
/* we did truncate it to 6 */
r = sd_memfd_get_size(m, &sz);
assert_se(r >= 0 && sz == 6);
/* map it, check content */
r = sd_memfd_map(m, 0, 12, (void **)&s);
assert_se(r >= 0);
/* we only see the truncated size */
assert_se(streq(s, "hello "));
/* it was already sealed */
r = sd_memfd_set_sealed(m, 1);
assert_se(r == -EALREADY);
/* we cannot break the seal, it is mapped */
r = sd_memfd_set_sealed(m, 0);
assert_se(r == -ETXTBSY);
/* unmap it; become the single owner */
assert_se(munmap(s, 12) == 0);
/* now we can do flip the sealing */
r = sd_memfd_set_sealed(m, 0);
assert_se(r == 0);
r = sd_memfd_get_sealed(m);
assert_se(r == 0);
r = sd_memfd_set_sealed(m, 1);
assert_se(r == 0);
r = sd_memfd_get_sealed(m);
assert_se(r == 1);
r = sd_memfd_set_sealed(m, 0);
assert_se(r == 0);
r = sd_memfd_get_sealed(m);
assert_se(r == 0);
/* seek at 2, read() 2 bytes */
assert_se(lseek(fd, 2, SEEK_SET) == 2);
assert_se(read(fd, buf, 2) == 2);
/* check content */
assert_se(memcmp(buf, "ll", 2) == 0);
/* writev it out*/
iov[0].iov_base = (char *)"ABC";
iov[0].iov_len = 3;
iov[1].iov_base = (char *)"DEF";
iov[1].iov_len = 3;
iov[2].iov_base = (char *)"GHI";
iov[2].iov_len = 3;
assert_se(pwritev(fd, iov, 3, 0) == 9);
/* readv it back */
iov[0].iov_base = bufv[0];
iov[0].iov_len = 3;
iov[1].iov_base = bufv[1];
iov[1].iov_len = 3;
iov[2].iov_base = bufv[2];
iov[2].iov_len = 3;
assert_se(preadv(fd, iov, 3, 0) == 9);
/* check content */
assert_se(memcmp(bufv[0], "ABC", 3) == 0);
assert_se(memcmp(bufv[1], "DEF", 3) == 0);
assert_se(memcmp(bufv[2], "GHI", 3) == 0);
sd_memfd_free(m);
return 0;
}
|
