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/*
* cook - file construction tool
* Copyright (C) 1995, 1997, 1999, 2006, 2007 Peter Miller;
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
*
* MANIFEST: functions to manipulate identifier fingerprints
*/
#include <common/ac/stdio.h>
#include <common/ac/string.h>
#include <common/fp/ident.h>
#include <common/fp/combined.h>
#include <common/fp/crc32.h>
#include <common/trace.h>
typedef struct ident_ty ident_ty;
struct ident_ty
{
FINGERPRINT_BASE_CLASS
fingerprint_ty *combined;
fingerprint_ty *crc32;
};
static void
ident_constructor(fingerprint_ty *p)
{
ident_ty *f;
trace(("constructor\n"));
f = (ident_ty *)p;
f->combined = fingerprint_new(&fp_combined);
f->crc32 = fingerprint_new(&fp_crc32);
}
static void
ident_destructor(fingerprint_ty *p)
{
ident_ty *f;
f = (ident_ty *)p;
fingerprint_delete(f->combined);
fingerprint_delete(f->crc32);
}
static void
ident_addn(fingerprint_ty *p, const void *s, size_t n)
{
ident_ty *f;
f = (ident_ty *)p;
fingerprint_addn(f->combined, s, n);
}
static int
ident_hash(fingerprint_ty *p, unsigned char *h, size_t h_len)
{
ident_ty *f;
int nbytes;
unsigned char t[1024];
f = (ident_ty *)p;
nbytes = fingerprint_hash(f->combined, t, sizeof(t));
fingerprint_addn(f->crc32, t, nbytes);
nbytes = fingerprint_hash(f->crc32, h, h_len);
return nbytes;
}
static void
ident_sum(fingerprint_ty *p, char *s, size_t s_len)
{
unsigned char h[1024];
unsigned long x;
int nbytes;
static char digits[] = "0123456789";
char *cp;
nbytes = ident_hash(p, h, sizeof(h));
assert(nbytes == 4);
/*
* watch out for 64-bit longs vs 32-bit ints
*/
x =
(
(unsigned long)h[0]
|
((unsigned long)h[1] << 8)
|
((unsigned long)h[2] << 16)
|
((unsigned long)h[3] << 24)
);
snprintf(s, s_len, "%8.8lx", x);
/*
* some older stdio implementations don't grok the above format
* string, so hunt down and kill and spaces.
*/
for (cp = s; *cp; ++cp)
if (*cp == ' ')
*cp = '0';
/*
* This forces the first character to be a letter, so
* the result is a valid identifier in most computer
* languages. The strchr makes it not ASCII specific.
*/
cp = strchr(digits, *s);
if (cp)
*s = "ghijklmnop"[cp - digits];
}
fingerprint_methods_ty fp_ident =
{
sizeof(ident_ty),
"identifier",
ident_constructor,
ident_destructor,
ident_addn,
ident_hash,
ident_sum
};
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