[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>

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

#include <linux/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 = 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
	12	/* boot_id depends on sysctl */
	13	#if defined(CONFIG_SYSCTL)
	14
	15	#include <linux/fs.h>
	16	#include <linux/file.h>
	17	#include <linux/sched.h>
	18	#include <linux/uaccess.h>
	19	#include <wrapper/random.h>
	20
	21	/*
	22	* Returns string boot id.
	23	*/
	24	int wrapper_get_bootid(char *bootid)
	25	{
	26	struct file *file;
	27	int ret;
	28	ssize_t len;
	29
	30	file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
	31	if (IS_ERR(file))
	32	return PTR_ERR(file);
	33
	34	len = kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
	35	if (len != BOOT_ID_LEN - 1) {
	36	ret = -EINVAL;
	37	goto end;
	38	}
	39
	40	bootid[BOOT_ID_LEN - 1] = '\0';
	41	ret = 0;
	42	end:
	43	filp_close(file, current->files);
	44	return ret;
	45	}
	46	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	47
	48	#else
	49
	50	int wrapper_get_bootid(char *bootid)
	51	{
	52	return -ENOSYS;
	53	}
	54	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	55
	56	#endif