[lttng-modules.git] / src / wrapper / random.c

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * wrapper/random.c
 *
 * wrapper around bootid read. Read the boot id through the /proc filesystem.
 *
 * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <linux/errno.h>
#include <linux/module.h>

/* boot_id depends on sysctl */
#if defined(CONFIG_SYSCTL)

#include <wrapper/fs.h>
#include <linux/file.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <wrapper/random.h>

/*
 * Returns string boot id.
 */
int wrapper_get_bootid(char *bootid)
{
	struct file *file;
	int ret;
	ssize_t len;

	file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
	if (IS_ERR(file))
		return PTR_ERR(file);

	len = lttng_kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
	if (len != BOOT_ID_LEN - 1) {
		ret = -EINVAL;
		goto end;
	}

	bootid[BOOT_ID_LEN - 1] = '\0';
	ret = 0;
end:
	filp_close(file, current->files);
	return ret;
}
EXPORT_SYMBOL_GPL(wrapper_get_bootid);

#else

int wrapper_get_bootid(char *bootid)
{
	return -ENOSYS;
}
EXPORT_SYMBOL_GPL(wrapper_get_bootid);

#endif
Commit	Line	Data
	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
	2	*
	3	* wrapper/random.c
	4	*
	5	* wrapper around bootid read. Read the boot id through the /proc filesystem.
	6	*
	7	* Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*/
	9
	10	#include <linux/errno.h>
	11	#include <linux/module.h>
	12
	13	/* boot_id depends on sysctl */
	14	#if defined(CONFIG_SYSCTL)
	15
	16	#include <wrapper/fs.h>
	17	#include <linux/file.h>
	18	#include <linux/sched.h>
	19	#include <linux/uaccess.h>
	20	#include <wrapper/random.h>
	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;
	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
	35	len = lttng_kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
	36	if (len != BOOT_ID_LEN - 1) {
	37	ret = -EINVAL;
	38	goto end;
	39	}
	40
	41	bootid[BOOT_ID_LEN - 1] = '\0';
	42	ret = 0;
	43	end:
	44	filp_close(file, current->files);
	45	return ret;
	46	}
	47	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	48
	49	#else
	50
	51	int wrapper_get_bootid(char *bootid)
	52	{
	53	return -ENOSYS;
	54	}
	55	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	56
	57	#endif