Commit | Line | Data |
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b7cdc182 | 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
9f36eaed | 2 | * |
886d51a3 | 3 | * wrapper/random.c |
a82c63f1 | 4 | * |
5b4ea313 | 5 | * wrapper around bootid read. Read the boot id through the /proc filesystem. |
a82c63f1 | 6 | * |
886d51a3 | 7 | * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
a82c63f1 MD |
8 | */ |
9 | ||
2fa61a31 | 10 | #include <linux/errno.h> |
477c93ad | 11 | #include <linux/module.h> |
2fa61a31 | 12 | |
a82c63f1 MD |
13 | /* boot_id depends on sysctl */ |
14 | #if defined(CONFIG_SYSCTL) | |
15 | ||
62d0a59c | 16 | #include <wrapper/fs.h> |
a82c63f1 MD |
17 | #include <linux/file.h> |
18 | #include <linux/sched.h> | |
19 | #include <linux/uaccess.h> | |
5a2f5e92 | 20 | #include <wrapper/random.h> |
a82c63f1 MD |
21 | |
22 | /* | |
23 | * Returns string boot id. | |
24 | */ | |
25 | int wrapper_get_bootid(char *bootid) | |
26 | { | |
27 | struct file *file; | |
28 | int ret; | |
29 | ssize_t len; | |
a82c63f1 MD |
30 | |
31 | file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0); | |
32 | if (IS_ERR(file)) | |
33 | return PTR_ERR(file); | |
34 | ||
62d0a59c | 35 | len = lttng_kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos); |
a82c63f1 MD |
36 | if (len != BOOT_ID_LEN - 1) { |
37 | ret = -EINVAL; | |
38 | goto end; | |
39 | } | |
1e543e7c | 40 | |
a82c63f1 MD |
41 | bootid[BOOT_ID_LEN - 1] = '\0'; |
42 | ret = 0; | |
43 | end: | |
a82c63f1 MD |
44 | filp_close(file, current->files); |
45 | return ret; | |
46 | } | |
1c999280 | 47 | EXPORT_SYMBOL_GPL(wrapper_get_bootid); |
a82c63f1 MD |
48 | |
49 | #else | |
50 | ||
51 | int wrapper_get_bootid(char *bootid) | |
52 | { | |
53 | return -ENOSYS; | |
54 | } | |
1c999280 | 55 | EXPORT_SYMBOL_GPL(wrapper_get_bootid); |
a82c63f1 MD |
56 | |
57 | #endif |