[Refactor] Refactor bignum header file into several files

configure.ac

@@ -1310,6 +1310,9 @@ openssl)
   ;;
 esac
 
+AM_CONDITIONAL([USE_NUM_GMP], [test "x$set_bignum" = "xgmp"])
+AM_CONDITIONAL([USE_NUM_OPENSSL], [test "x$set_bignum" = "xopenssl"])
+
 AC_MSG_CHECKING([whether to build test_pivx])
 if test x$use_tests = xyes; then
   AC_MSG_RESULT([yes])

src/Makefile.am

@@ -336,6 +336,7 @@ libzerocoin_libbitcoin_zerocoin_a_SOURCES = \
   libzerocoin/SerialNumberSignatureOfKnowledge.h \
   libzerocoin/SpendType.h \
   libzerocoin/ZerocoinDefines.h \
+  libzerocoin/bignum.cpp \
   libzerocoin/Accumulator.cpp \
   libzerocoin/AccumulatorProofOfKnowledge.cpp \
   libzerocoin/Coin.cpp \
@@ -345,6 +346,12 @@ libzerocoin_libbitcoin_zerocoin_a_SOURCES = \
   libzerocoin/ParamGeneration.cpp \
   libzerocoin/Params.cpp \
   libzerocoin/SerialNumberSignatureOfKnowledge.cpp
+if USE_NUM_GMP
+  libzerocoin_libbitcoin_zerocoin_a_SOURCES += libzerocoin/bignum_gmp.cpp
+endif
+if USE_NUM_OPENSSL
+  libzerocoin_libbitcoin_zerocoin_a_SOURCES += libzerocoin/bignum_openssl.cpp
+endif
 
 # common: shared between pivxd, and pivx-qt and non-server tools
 libbitcoin_common_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)

src/libzerocoin/bignum.cpp

@@ -0,0 +1,63 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2012 The Bitcoin developers
+// Copyright (c) 2017-2019 The PIVX developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "bignum.h"
+
+#if defined(USE_NUM_GMP)
+#include "bignum_gmp.cpp"
+#endif
+
+#if defined(USE_NUM_OPENSSL)
+#include "bignum_openssl.cpp"
+#endif
+
+std::string CBigNum::GetHex() const
+{
+    return ToString(16);
+}
+
+std::string CBigNum::GetDec() const
+{
+    return ToString(10);
+}
+
+CBigNum CBigNum::pow(const int e) const
+{
+    return this->pow(CBigNum(e));
+}
+
+void CBigNum::SetHex(const std::string& str)
+{
+    SetHexBool(str);
+}
+
+CBigNum& CBigNum::operator/=(const CBigNum& b)
+{
+    *this = *this / b;
+    return *this;
+}
+
+CBigNum& CBigNum::operator%=(const CBigNum& b)
+{
+    *this = *this % b;
+    return *this;
+}
+
+const CBigNum CBigNum::operator++(int)
+{
+    // postfix operator
+    const CBigNum ret = *this;
+    ++(*this);
+    return ret;
+}
+
+const CBigNum CBigNum::operator--(int)
+{
+    // postfix operator
+    const CBigNum ret = *this;
+    --(*this);
+    return ret;
+}