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/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2002-2009. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* %CopyrightEnd%
*/
#include "eidef.h"
#if defined(HAVE_GMP_H) && defined(HAVE_LIBGMP)
#include <gmp.h>
#include "eidef.h"
#include "eiext.h"
#include "putget.h"
int ei_decode_bignum(const char *buf, int *index, mpz_t obj)
{
const char *s = buf + *index;
const char *s0 = s;
int arity;
int sign;
unsigned long n;
switch (get8(s)) {
case ERL_SMALL_INTEGER_EXT:
n = get8(s);
mpz_set_ui(obj, n);
break;
case ERL_INTEGER_EXT:
n = get32be(s);
mpz_set_ui(obj, n);
break;
case ERL_SMALL_BIG_EXT:
arity = get8(s);
goto decode_bytes;
case ERL_LARGE_BIG_EXT:
arity = get32be(s);
decode_bytes:
sign = get8(s);
mpz_import(obj, arity, -1, 1, 0, 0, s);
s += arity;
if (sign) {
mpz_neg(obj, obj);
}
break;
default:
return -1;
}
*index += s-s0;
return 0;
}
#endif /* HAVE_GMP_H && HAVE_LIBGMP */
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