LXR linux/fs/proc/kmsg.c

   1/*
   2 *  linux/fs/proc/kmsg.c
   3 *
   4 *  Copyright (C) 1992  by Linus Torvalds
   5 *
   6 */
   7
   8#include <linux/types.h>
   9#include <linux/errno.h>
  10#include <linux/time.h>
  11#include <linux/kernel.h>
  12#include <linux/poll.h>
  13#include <linux/fs.h>
  14
  15#include <asm/uaccess.h>
  16#include <asm/io.h>
  17
  18extern wait_queue_head_t log_wait;
  19
  20extern int do_syslog(int type, char __user *bug, int count);
  21
  22static int kmsg_open(struct inode * inode, struct file * file)
  23{
  24        return do_syslog(1,NULL,0);
  25}
  26
  27static int kmsg_release(struct inode * inode, struct file * file)
  28{
  29        (void) do_syslog(0,NULL,0);
  30        return 0;
  31}
  32
  33static ssize_t kmsg_read(struct file *file, char __user *buf,
  34                         size_t count, loff_t *ppos)
  35{
  36        if ((file->f_flags & O_NONBLOCK) && !do_syslog(9, NULL, 0))
  37                return -EAGAIN;
  38        return do_syslog(2, buf, count);
  39}
  40
  41static unsigned int kmsg_poll(struct file *file, poll_table *wait)
  42{
  43        poll_wait(file, &log_wait, wait);
  44        if (do_syslog(9, NULL, 0))
  45                return POLLIN | POLLRDNORM;
  46        return 0;
  47}
  48
  49
  50const struct file_operations proc_kmsg_operations = {
  51        .read           = kmsg_read,
  52        .poll           = kmsg_poll,
  53        .open           = kmsg_open,
  54        .release        = kmsg_release,
  55};
  56