/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from tahoe: in_cksum.c 1.2 86/01/05
* from: @(#)in_cksum.c 1.3 (Berkeley) 1/19/91
* from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp
* $FreeBSD$
*/
#ifndef _MACHINE_IN_CKSUM_H_
#define _MACHINE_IN_CKSUM_H_ 1
#ifndef _SYS_CDEFS_H_
#error this file needs sys/cdefs.h as a prerequisite
#endif
/*
* MP safe (alfred)
*/
#include <sys/cdefs.h>
#define in_cksum(m, len) in_cksum_skip(m, len, 0)
/*
* It it useful to have an Internet checksum routine which is inlineable
* and optimized specifically for the task of computing IP header checksums
* in the normal case (where there are no options and the header length is
* therefore always exactly five 32-bit words.
*/
#if defined(__GNUCLIKE_ASM) && !defined(__INTEL_COMPILER)
static __inline u_int
in_cksum_hdr(const struct ip *ip)
{
register u_int sum = 0;
__asm __volatile (
"addl %1, %0\n"
"adcl %2, %0\n"
"adcl %3, %0\n"
"adcl %4, %0\n"
"adcl %5, %0\n"
"adcl $0, %0"
: "+r" (sum)
: "g" (((const u_int32_t *)ip)[0]),
"g" (((const u_int32_t *)ip)[1]),
"g" (((const u_int32_t *)ip)[2]),
"g" (((const u_int32_t *)ip)[3]),
"g" (((const u_int32_t *)ip)[4])
);
sum = (sum & 0xffff) + (sum >> 16);
if (sum > 0xffff)
sum -= 0xffff;
return ~sum & 0xffff;
}
static __inline void
in_cksum_update(struct ip *ip)
{
int __tmpsum;
__tmpsum = (int)ntohs(ip->ip_sum) + 256;
ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16));
}
static __inline u_short
in_addword(u_short sum, u_short b)
{
/* __volatile is necessary because the condition codes are used. */
__asm __volatile ("addw %1, %0" : "+r" (sum) : "r" (b));
__asm __volatile ("adcw $0, %0" : "+r" (sum));
return (sum);
}
static __inline u_short
in_pseudo(u_int sum, u_int b, u_int c)
{
/* __volatile is necessary because the condition codes are used. */
__asm __volatile ("addl %1, %0" : "+r" (sum) : "g" (b));
__asm __volatile ("adcl %1, %0" : "+r" (sum) : "g" (c));
__asm __volatile ("adcl $0, %0" : "+r" (sum));
sum = (sum & 0xffff) + (sum >> 16);
if (sum > 0xffff)
sum -= 0xffff;
return (sum);
}
#else
#define in_cksum_update(ip) \
do { \
int __tmpsum; \
__tmpsum = (int)ntohs(ip->ip_sum) + 256; \
ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); \
} while(0)
#endif
#ifdef _KERNEL
#if !defined(__GNUCLIKE_ASM) || defined(__INTEL_COMPILER)
u_int in_cksum_hdr(const struct ip *ip);
u_short in_addword(u_short sum, u_short b);
u_short in_pseudo(u_int sum, u_int b, u_int c);
#endif
u_short in_cksum_skip(struct mbuf *m, int len, int skip);
#endif /* _KERNEL */
#endif /* _MACHINE_IN_CKSUM_H_ */
