sum-att.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1996-2011 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* att
*/
#define att_description \
"The system 5 release 4 checksum. This is the default for \bsum\b \
when \bgetconf UNIVERSE\b is \batt\b. This is the only true sum; \
all of the other methods are order dependent."
#define att_options 0
#define att_match "att|sys5|s5|default"
#define att_open long_open
#define att_init long_init
#define att_print long_print
#define att_data long_data
#define att_scale 512
static int
att_block(register Sum_t* p, const void* s, size_t n)
{
register uint32_t c = ((Integral_t*)p)->sum;
register unsigned char* b = (unsigned char*)s;
register unsigned char* e = b + n;
while (b < e)
c += *b++;
((Integral_t*)p)->sum = c;
return 0;
}
static int
att_done(Sum_t* p)
{
register uint32_t c = ((Integral_t*)p)->sum;
c = (c & 0xffff) + ((c >> 16) & 0xffff);
c = (c & 0xffff) + (c >> 16);
((Integral_t*)p)->sum = c & 0xffff;
return short_done(p);
}