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-rw-r--r--lib/erl_interface/src/decode/decode_bignum.c75
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 */