Update License in File Headers
[novacoin.git] / src / bignum.h
index 450e809..bd42f77 100644 (file)
@@ -1,14 +1,15 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2011 The Bitcoin developers
 // Distributed under the MIT/X11 software license, see the accompanying
-// file license.txt or http://www.opensource.org/licenses/mit-license.php.
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#ifndef BITCOIN_BIGNUM_H
+#define BITCOIN_BIGNUM_H
 
 #include <stdexcept>
 #include <vector>
 #include <openssl/bn.h>
 
-
-
-
+#include "util.h"
 
 class bignum_error : public std::runtime_error
 {
@@ -76,7 +77,8 @@ public:
         BN_clear_free(this);
     }
 
-    CBigNum(char n)             { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
+    //CBigNum(char n) is not portable.  Use 'signed char' or 'unsigned char'.
+    CBigNum(signed char n)      { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
     CBigNum(short n)            { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
     CBigNum(int n)              { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
     CBigNum(long n)             { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
@@ -228,10 +230,13 @@ public:
     {
         std::vector<unsigned char> vch2(vch.size() + 4);
         unsigned int nSize = vch.size();
+        // BIGNUM's byte stream format expects 4 bytes of
+        // big endian size data info at the front
         vch2[0] = (nSize >> 24) & 0xff;
         vch2[1] = (nSize >> 16) & 0xff;
         vch2[2] = (nSize >> 8) & 0xff;
         vch2[3] = (nSize >> 0) & 0xff;
+        // swap data to big endian
         reverse_copy(vch.begin(), vch.end(), vch2.begin() + 4);
         BN_mpi2bn(&vch2[0], vch2.size(), this);
     }
@@ -239,7 +244,7 @@ public:
     std::vector<unsigned char> getvch() const
     {
         unsigned int nSize = BN_bn2mpi(this, NULL);
-        if (nSize < 4)
+        if (nSize <= 4)
             return std::vector<unsigned char>();
         std::vector<unsigned char> vch(nSize);
         BN_bn2mpi(this, &vch[0]);
@@ -291,12 +296,12 @@ public:
             psz++;
 
         // hex string to bignum
-        static char phexdigit[256] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,1,2,3,4,5,6,7,8,9,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0 };
+        static signed char phexdigit[256] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,1,2,3,4,5,6,7,8,9,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0 };
         *this = 0;
         while (isxdigit(*psz))
         {
             *this <<= 4;
-            int n = phexdigit[*psz++];
+            int n = phexdigit[(unsigned char)*psz++];
             *this += n;
         }
         if (fNegative)
@@ -308,7 +313,7 @@ public:
         CAutoBN_CTX pctx;
         CBigNum bnBase = nBase;
         CBigNum bn0 = 0;
-        string str;
+        std::string str;
         CBigNum bn = *this;
         BN_set_negative(&bn, false);
         CBigNum dv;
@@ -348,7 +353,7 @@ public:
     template<typename Stream>
     void Unserialize(Stream& s, int nType=0, int nVersion=VERSION)
     {
-        vector<unsigned char> vch;
+        std::vector<unsigned char> vch;
         ::Unserialize(s, vch, nType, nVersion);
         setvch(vch);
     }
@@ -530,3 +535,5 @@ inline bool operator<=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a,
 inline bool operator>=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) >= 0); }
 inline bool operator<(const CBigNum& a, const CBigNum& b)  { return (BN_cmp(&a, &b) < 0); }
 inline bool operator>(const CBigNum& a, const CBigNum& b)  { return (BN_cmp(&a, &b) > 0); }
+
+#endif