1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2002-2009. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights 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 */
|
