freebsd-nq/contrib/ipfilter/kmem.c
1997-02-09 22:50:16 +00:00

69 lines
1.3 KiB
C

/*
* (C)opyright 1993,1994,1995 by Darren Reed.
*
* Redistribution and use in source and binary forms are permitted
* provided that this notice is preserved and due credit is given
* to the original author and the contributors.
*/
/*
* kmemcpy() - copies n bytes from kernel memory into user buffer.
* returns 0 on success, -1 on error.
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/file.h>
#define KMEM "/dev/kmem"
#if !defined(lint) && defined(LIBC_SCCS)
static char sccsid[] = "@(#)kmem.c 1.4 1/12/96 (C) 1992 Darren Reed";
static char rcsid[] = "$Id: kmem.c,v 2.0.1.1 1997/01/09 15:14:44 darrenr Exp $";
#endif
static int kmemfd = -1;
int openkmem()
{
if ((kmemfd = open(KMEM,O_RDONLY)) == -1)
{
perror("kmeminit:open");
return -1;
}
return kmemfd;
}
int kmemcpy(buf, pos, n)
register char *buf;
long pos;
register int n;
{
register int r;
if (!n)
return 0;
if (kmemfd == -1)
if (openkmem() == -1)
return -1;
if (lseek(kmemfd, pos, 0) == -1)
{
perror("kmemcpy:lseek");
return -1;
}
while ((r = read(kmemfd, buf, n)) < n)
if (r <= 0)
{
perror("kmemcpy:read");
return -1;
}
else
{
buf += r;
n -= r;
}
return 0;
}