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9#include <linux/types.h>
10#include <linux/errno.h>
11#include <linux/time.h>
12#include <linux/kernel.h>
13#include <linux/poll.h>
14#include <linux/proc_fs.h>
15#include <linux/fs.h>
16#include <linux/syslog.h>
17
18#include <linux/uaccess.h>
19#include <asm/io.h>
20
21extern wait_queue_head_t log_wait;
22
23static int kmsg_open(struct inode * inode, struct file * file)
24{
25 return do_syslog(SYSLOG_ACTION_OPEN, NULL, 0, SYSLOG_FROM_PROC);
26}
27
28static int kmsg_release(struct inode * inode, struct file * file)
29{
30 (void) do_syslog(SYSLOG_ACTION_CLOSE, NULL, 0, SYSLOG_FROM_PROC);
31 return 0;
32}
33
34static ssize_t kmsg_read(struct file *file, char __user *buf,
35 size_t count, loff_t *ppos)
36{
37 if ((file->f_flags & O_NONBLOCK) &&
38 !do_syslog(SYSLOG_ACTION_SIZE_UNREAD, NULL, 0, SYSLOG_FROM_PROC))
39 return -EAGAIN;
40 return do_syslog(SYSLOG_ACTION_READ, buf, count, SYSLOG_FROM_PROC);
41}
42
43static __poll_t kmsg_poll(struct file *file, poll_table *wait)
44{
45 poll_wait(file, &log_wait, wait);
46 if (do_syslog(SYSLOG_ACTION_SIZE_UNREAD, NULL, 0, SYSLOG_FROM_PROC))
47 return EPOLLIN | EPOLLRDNORM;
48 return 0;
49}
50
51
52static const struct proc_ops kmsg_proc_ops = {
53 .proc_flags = PROC_ENTRY_PERMANENT,
54 .proc_read = kmsg_read,
55 .proc_poll = kmsg_poll,
56 .proc_open = kmsg_open,
57 .proc_release = kmsg_release,
58 .proc_lseek = generic_file_llseek,
59};
60
61static int __init proc_kmsg_init(void)
62{
63 proc_create("kmsg", S_IRUSR, NULL, &kmsg_proc_ops);
64 return 0;
65}
66fs_initcall(proc_kmsg_init);
67
