64 lines
1.5 KiB
C
64 lines
1.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* linux/fs/proc/kmsg.c
|
|
*
|
|
* Copyright (C) 1992 by Linus Torvalds
|
|
*
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/time.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/syslog.h>
|
|
|
|
#include <asm/io.h>
|
|
|
|
static int kmsg_open(struct inode * inode, struct file * file)
|
|
{
|
|
return do_syslog(SYSLOG_ACTION_OPEN, NULL, 0, SYSLOG_FROM_PROC);
|
|
}
|
|
|
|
static int kmsg_release(struct inode * inode, struct file * file)
|
|
{
|
|
(void) do_syslog(SYSLOG_ACTION_CLOSE, NULL, 0, SYSLOG_FROM_PROC);
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t kmsg_read(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
if ((file->f_flags & O_NONBLOCK) &&
|
|
!do_syslog(SYSLOG_ACTION_SIZE_UNREAD, NULL, 0, SYSLOG_FROM_PROC))
|
|
return -EAGAIN;
|
|
return do_syslog(SYSLOG_ACTION_READ, buf, count, SYSLOG_FROM_PROC);
|
|
}
|
|
|
|
static __poll_t kmsg_poll(struct file *file, poll_table *wait)
|
|
{
|
|
poll_wait(file, &log_wait, wait);
|
|
if (do_syslog(SYSLOG_ACTION_SIZE_UNREAD, NULL, 0, SYSLOG_FROM_PROC))
|
|
return EPOLLIN | EPOLLRDNORM;
|
|
return 0;
|
|
}
|
|
|
|
|
|
static const struct proc_ops kmsg_proc_ops = {
|
|
.proc_flags = PROC_ENTRY_PERMANENT,
|
|
.proc_read = kmsg_read,
|
|
.proc_poll = kmsg_poll,
|
|
.proc_open = kmsg_open,
|
|
.proc_release = kmsg_release,
|
|
.proc_lseek = generic_file_llseek,
|
|
};
|
|
|
|
static int __init proc_kmsg_init(void)
|
|
{
|
|
proc_create("kmsg", S_IRUSR, NULL, &kmsg_proc_ops);
|
|
return 0;
|
|
}
|
|
fs_initcall(proc_kmsg_init);
|