diff options
Diffstat (limited to 'lib/erl_interface/src/decode/decode_bignum.c')
-rw-r--r-- | lib/erl_interface/src/decode/decode_bignum.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/lib/erl_interface/src/decode/decode_bignum.c b/lib/erl_interface/src/decode/decode_bignum.c new file mode 100644 index 0000000000..f10052f9fe --- /dev/null +++ b/lib/erl_interface/src/decode/decode_bignum.c @@ -0,0 +1,75 @@ +/* + * %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 */ |